Patent Publication Number: US-2023148849-A1

Title: Medical system and cannulation method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority to U.S. Provisional Application Nos. 63/280,716 filed Nov. 18, 2021; 63/294,453 filed Dec. 29, 2021; and 63/294,482 filed Dec. 29, 2021, the entire contents of each of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     A technique called endoscopic retrograde cholangiopancreatography (ERCP) is known that captures an X-ray image or a CT image of biliary duct by inserting a cannula into a biliary duct from a treatment tool channel of an endoscope, injecting a contrast agent from the cannula, and performing X-ray imaging or CT imaging. A robotic catheter system for performing ERCP by remotely operating a catheter system is also known. 
     In the prior art, an electric catheter is known to be operated by an operator workstation or controller by an operator in a robotic catheter system using a catheter whose operation is electrically driven. The operator workstation is so-called a console-type operation device, equipped with buttons, levers, etc. for example. The operator is seated in front of the console and operates the buttons, levers, etc. The controller is a handy operation device equipped with, for example, dials, D-pad, buttons, etc. The operator holds the controller and operates the dials, the D-pad, buttons, etc. 
     SUMMARY 
     Accordingly, there is provided a medical system comprising: an endoscope configured to electrically drive an endoscopic operation, the endoscopic operation comprising at least one of a forward and backward movement of an insertion section, a bending angle of a bending section of the insertion section, and a rolling rotation of the insertion section, the endoscope being configured to capture an endoscope image and a processor comprising hardware, the processor being configured to control the endoscopic operation to achieve a second positioning subsequent to a first positioning, the first positioning being where the insertion section is positioned with respect to a papillary portion of a duodenum, the second positioning positions a distal end section of the insertion section with respect to a papillary portion of the duodenum based on the endoscope image. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    shows organs and tissues involved in the ERCP procedure. 
         FIG.  2    shows a flow of the ERCP procedure. 
         FIG.  3    shows a schematic diagram of the form of papillary portion viewed directly from the front, and examples of individual differences in shape. 
         FIG.  4    is a cross-sectional view showing the form of a luminal tissue and its opening. 
         FIG.  5    shows a basic configuration example of a medical system according to the present embodiment. 
         FIG.  6    shows a first flow of the procedure according to the present embodiment. 
         FIGS.  7   a  and  7   b    show a comparison between a case without an overtube and a case with an overtube. 
         FIG.  8    shows the vicinity of the distal end of an endoscope positioned by an overtube and a balloon. 
         FIG.  9    shows a detailed configuration example of a medical system. 
         FIG.  10    shows a detailed configuration example of a drive control device. 
         FIG.  11    is a schematic view of an endoscope including a bending section and a driving mechanism thereof. 
         FIGS.  12   a - 12   c    show a detailed configuration example of a forward/backward drive device. 
         FIG.  13    is a perspective view of a connecting section including a rolling drive device. 
         FIGS.  14   a  and  14   b    show a detailed configuration example of a distal end section of an endoscope including a raising base of a treatment tool. 
         FIG.  15    shows a detailed configuration example of a treatment tool. 
         FIGS.  16   a  and  16   b    show a configuration example of a drive system of an overtube. 
         FIG.  17    shows a configuration example of a drive system of a balloon. 
         FIG.  18    shows a first modification of a holding member. 
         FIG.  19    shows a second modification of a holding member. 
         FIG.  20    shows an organ structure of a patient who had a gastric bypass surgery according to the Roux-en Y method. 
         FIG.  21    shows a modification of an operation device for manually operating an electric endoscope. 
         FIG.  22    is a diagram showing an operation of inserting a cannula when using non-electric endoscope and cannula. 
         FIG.  23    shows a basic configuration example of a medical system according to another embodiment. 
         FIG.  24    shows a detailed configuration example of an electric treatment tool. 
         FIG.  25    shows a first detailed configuration example of a treatment tool operation device. 
         FIG.  26    shows a block configuration example of a medical system. 
         FIG.  27    shows a first detailed configuration example of a first base. 
         FIG.  28    shows a second detailed configuration example of the first base. 
         FIG.  29    shows an example of control of a force feedback. 
         FIG.  30    shows an example of control of force feedback using an image. 
         FIG.  31    shows a flow of ERCP procedure using a medical system of the other embodiment. 
         FIG.  32    shows a flow in the case of enabling/disabling functions based on the type of treatment tool. 
         FIG.  33    shows a second detailed configuration example of the treatment tool operation device. 
         FIGS.  34   a  and  34   b    show a third detailed configuration example of the treatment tool operation device. 
         FIG.  35    shows a detailed configuration example of a medical system. 
         FIG.  36    shows the vicinity of the distal end of an endoscope positioned at a papillary portion of duodenum. 
         FIGS.  37   a - 37   c    show a detailed configuration example of a forward/backward drive device. 
         FIGS.  38   a  and  38   b    show a detailed configuration example of a distal end section of an endoscope including a raising base of a treatment tool. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Further, when a first element is described as being “connected” or “coupled” to a second element, such description includes embodiments in which the first and second elements are directly connected or coupled to each other, and also includes embodiments in which the first and second elements are indirectly connected or coupled to each other with one or more other intervening elements in between. 
     Explanation of ERCP 
     The present embodiment relates to automatic control when performing ERCP using an electric medical system. ERCP stands for Endoscopic Retrograde Cholangiopancreatography. First, before describing the present embodiment, the details of procedure of ERCP is described below. 
       FIG.  1    shows organs and tissues involved in the ERCP procedure. The organs include multiple types of tissues, forming a unique structure with a specific function. In FIG.  1 , the liver, gallbladder, pancreas, esophagus, stomach, and duodenum are shown as organs. Tissues are formed by related cells combined, and examples include blood vessels, muscles, skin, and the like. In  FIG.  1   , a biliary duct and a pancreatic duct are shown as tissues. 
     The biliary duct is the target of the ERCP procedure. The biliary duct is a pipeline for allowing the bile produced in the liver to flow into the duodenum. When approaching the biliary duct using an endoscope, a treatment tool inserted into the channel of the endoscope is inserted to the biliary duct from the papillary portion of the duodenum while holding the endoscope at the position of the duodenum. Hereinafter, the papillary portion of the duodenum is simply referred to as a papillary portion. The papillary portion is a region including an opening of the luminal tissue with respect to the duodenum. Not only the opening but also the structure around the opening is referred to as a papillary portion. The opening of the luminal tissue is the opening of a common duct with respect to the duodenum. The common duct is formed as the confluence of the biliary duct and pancreatic duct. However, as described later, the papillary portion largely varies between individuals. For example, in some cases, the biliary duct opens directly to the duodenum without being merged with the pancreatic duct. In this case, the opening of the luminal tissue is the opening of the biliary duct. 
       FIG.  2    shows a flow of the ERCP procedure. In ERCP, a side-viewing type endoscope in which a camera, an illumination lens, and an opening of a treatment tool channel are provided on a side surface of a distal end section of the endoscope is used. The camera is also referred to as an imaging device. 
     In the endoscope insertion step, the insertion section of the endoscope is inserted from the mouth to the duodenum through the esophagus and stomach. At this time, the insertion section is inserted until the papillary portion becomes roughly visible in the field of view of the endoscope. Next, in the positioning step, the position of the endoscope is adjusted relative to the papillary portion. Specifically, the position of the distal end section of the endoscope is adjusted so that the papillary portion is within the imaging range of the camera of the endoscope. Alternatively, the position of the distal end section of the endoscope is adjusted so that the camera of the endoscope is facing directly in front of the papillary portion and the papillary portion appears in the center of the field of view. 
     Then, in the cannulation step, a cannula is inserted from the papillary portion into the biliary duct. Specifically, the cannula is inserted into the treatment tool channel of the endoscope so that the cannula protrudes from the channel opening of the distal end section of the endoscope. The distal end of the cannula is inserted into the common duct from the opening of the common duct, and the cannula is further inserted through the confluence of the biliary duct and the pancreatic duct toward the direction of the biliary duct. Cannulation refers to insertion of a cannula into a body. A cannula is a medical tube that is inserted into a body for medical purposes. 
     Next, in the contrast radiography and imaging step, a contrast agent is injected into the cannula and ejected into the biliary duct from the distal end of the cannula. By performing X-ray or CT imaging in this state, an X-ray image or a CT (Computed Tomography) image showing the biliary duct, gallbladder, and pancreatic duct can be obtained. The procedure of ERCP has been described. After the procedure, various treatments are performed according to the results of diagnosis based on the X-ray image or CT image. An example of the treatment is described below. 
     In a guide wire insertion step, a guide wire is inserted into a cannula so that the guide wire is protruded from the distal end of the cannula, and the guide wire is inserted into the biliary duct. In a cannula removing step, the cannula is removed while leaving the guide wire inside the biliary duct. As a result, only the guide wire protrudes from the distal end section of the endoscope, indwelling in the biliary duct. Next, in a treatment tool insertion step, the treatment tool is inserted into the biliary duct along the guide wire. An example of a treatment tool is a basket or stent. The basket is used with a catheter. While allowing the guide wire to pass through the catheter, the catheter is inserted into the biliary duct along the guide wire. A basket made of a plurality of metal wires is inserted into the biliary duct from the distal end of the catheter, an object to be removed, such as a gallstone, is placed in the basket and held, and the object to be removed is taken out from the biliary duct by removing the basket and catheter in this state from the biliary duct. A stent can also be used in a similar manner with a catheter and inserted into the biliary duct from the distal end of the catheter. The narrow portion of the biliary duct can be widened by inserting a stent; further, by keeping the stent therein, the narrow portion can be held in a widened state by the indwelling stent. 
     The ERCP procedure is performed as described above; however, in the positioning step, the procedure becomes difficult due to the individual differences in the papillary portions or luminal tissues. The following describes this issue with reference to  FIGS.  3  and  4   . 
       FIG.  3    is a diagram schematically showing the form of the papillary portion as viewed directly from the front thereof, and examples of individual differences of the papillary portion. As shown in the schematic diagram, structures peculiar to the papillary portion are present around the main papilla, which is the opening of the luminal tissue. Specifically, structures called frenulum, encircling fold, and oral protrusion can be present around the main papilla. 
     Although the schematic diagram shows a typical form of the papillary portion, as shown in Examples a to d, the form of the papillary portion varies between individuals and different for each patient. Examples of the differences include unclear main papilla, frenulum, encircling fold, or oral protrusion, and other forms significantly different from the typical form. In addition, the opening of the luminal tissue is often closed; in this case, it is difficult to precisely recognize the opening by visual observation. 
       FIG.  4    is a cross-sectional view showing the form of the luminal tissue and its opening. The forms of the luminal tissue and its opening are classified into Type I(Y-shaped), Type II(V-shaped), and Type III(U-shaped or separated). In Type I, a biliary duct and a pancreatic duct merge into a common duct at the confluence thereof, and the common duct opens to the papillary portion. In Type II, the biliary duct and the pancreatic duct open to the papillary portion at the confluence thereof, and there is no common duct. In Type III, the biliary duct and the pancreatic duct are separately open to the papillary portion and there are no confluence or common duct. Type I is most common, but there are also Type II and Type III patients. 
     When cannulation into the biliary duct is performed, it is basically performed by referring to an endoscope image showing the papillary portion, as shown in Examples a to d in  FIG.  3   . As described with reference to  FIGS.  3  and  4   , there are various forms of papillary portion and luminal tissue, and it is difficult to specify the insertion position and insertion direction of the cannula from the endoscope image. 
     On the other hand, the operator estimates the position of the opening and the travelling direction of the biliary duct based on past cases, experiences, and the like while viewing the endoscope image, and tries to insert the cannula from the opening into the biliary duct according to the estimation. At this time, in order to more accurately estimate the position of the opening and the travelling direction of the biliary duct, it is desirable that the position of the papillary portion in the image and the angle of view of the image are easy to compare with those in the past cases or are familiar to the operator. 
     As shown in  FIG.  1   , such positioning of the endoscope is performed by operating the distal end of the endoscope insertion section reaching the duodenum from outside the body. However, since the insertion section and the organ through which the insertion section passes are flexible, the operation performed at the base end of the insertion section is not easily transmitted to the distal end section. In addition, since the distal end section of the endoscope is not fixed to the duodenum and is free to move relative to the duodenum, the distal end section of the endoscope is not stable with respect to the papillary portion, and the positional relationship between the distal end section and the papillary portion is not easily determined. For these reasons, it is difficult to adjust the position of the distal end section of the endoscope so that the field of view of the endoscope is facing directly in front of the papillary portion or so that the papillary portion appears in the center of the field of view. 
     Procedure Flow and Medical System According to the Present Embodiment 
     Therefore, in the present embodiment, the above-described positioning is automated by an electric medical system to assist the ERCP procedure. Further, by adding a configuration in which the insertion section of the endoscope is held in the duodenum, the electrically-driven force can be easily transmitted to the distal end section of the endoscope and the position of the distal end section can be desirably controlled. The details of this structure are described below. 
       FIG.  5    shows a basic configuration example of a medical system  10  according to the present embodiment. The medical system  10  includes an endoscope  100 , an overtube  710 , a balloon  720 , a treatment tool  400 , and a control device  600 . The medical system  10  is also referred to as an endoscope system or an electric endoscope system. 
     The overtube  710  is a tube with a variable hardness that covers the insertion section  110  of the endoscope  100 . The balloon  720  is provided near the distal end on the outer side of the overtube  710 . When the endoscope  100  and the overtube  710  are inserted into the body, at least the bending section of the insertion section  110  is exposed from the distal end of the overtube  710 . The bending section refers to a section structured to be bent at an angle corresponding to the bending operation in the vicinity of the distal end of the insertion section  110 . The base end of the overtube  710  is present outside the body. The base end side of the insertion section  110  is exposed from the base end of the overtube  710 . 
     An insertion opening  190  of the treatment tool is provided at the base end side of the insertion section  110 , and a treatment tool channel for allowing the treatment tool  400  to pass through from the insertion opening  190  to the opening of the distal end section  130  is provided inside the insertion section  110 . The insertion opening  190  of the treatment tool is also called a forceps opening; however, the treatment tool to be used is not limited to forceps. 
     The endoscope  100  is detachably connected to a control device  600  using connectors  201  and  202 . The control device  600  includes a drive control device  200  to which the connector  201  is connected, and a video control device  500  to which the connector  202  is connected. The drive control device  200  controls the electrical driving of the endoscope  100  via the connector  201 . Although not shown in  FIG.  5   , an operation device for manually operating the electrical driving may be connected to the drive control device  200 . The video control device  500  receives an image signal from a camera provided at the distal end section  130  of the endoscope  100  via the connector  202 , generates a display image from the image signal, and displays it on a display device (not shown). In  FIG.  5   , the drive control device  200  and the video control device  500  are shown as separate devices, but they may be structured as a single device. In this case, the connectors  201  and  202  may be integrated into a single connector. 
       FIG.  6    shows a first flow of the procedure in the present embodiment. Here, an electric endoscope is assumed in which the forward and backward movement of the insertion section  110  of the endoscope  100 , the bending of the bending section of the insertion section  110 , and the rolling rotation of the insertion section  110  are electrically driven. However, it is sufficient that at least one of these functions is electrically driven. The term “electrical driving” means that the endoscope is driven by a motor or the like based on an electrical signal for controlling the endoscopic operation. For example, when the electrical driving is manually operated, an operation input to the operation device is converted into an electrical signal, and the endoscope is driven based on the electrical signal. In the following, the forward and backward movement may be simply referred to as “forward/backward movement”. 
     In step S 1 , the operator inserts the insertion section  110  of the endoscope  100  and the overtube  710  into the duodenum. More specifically, in a state where the insertion section  110  is inserted into the overtube, the insertion section  110  and the overtube  710  are inserted into the duodenum together. The overtube  710 , which is changeable in hardness, is soft in step S 1 . For example, the operator can move the insertion section  110  and the overtube  710  forward by a non-electrically-driven manual operation so that they are inserted into the body. The non-electrical driving means that the endoscope  100  is not electrically driven by a motor or the like, instead, the force applied to the operation section is directly transmitted to the endoscope by a wire or the like, thereby operating the endoscope. For example, in the present embodiment, steps S 1  to S 4  are not electrically driven. In this case, it is sufficient that at least the forward/backward movement is not electrically driven, and the bending, the rolling rotation, or both may be manually operated by electrical driving. 
     In step S 2 , the operator inserts the insertion section  110  until the distal end section  130  reaches the vicinity of the papillary portion. For example, when the operator manually inserts the insertion section  110  by non-electrical driving, the operator inserts the insertion section  110  until the papillary portion becomes visible in the endoscope image. At this point, the distal end of the endoscope  100  does not need to accurately reach the papillary portion; the distal end of the endoscope  100  may reach a position before the papillary portion or past the papillary portion. 
     In step S 3 , the operator fixes the distal end of the overtube  710  to the duodenum. As an example, the operator performs an operation to inflate the balloon  720  provided near the distal end of the overtube  710 , and fixes the distal end of the overtube  710  to the duodenum by the balloon  720 . In step S 4 , the operator performs an operation to harden the overtube  710 . At this time, the overtube  710  is hardened while maintaining its shape in a state immediately before hardening, that is, the shape when it is inserted from the mouth to the duodenum. As a result, the insertion section  110  is held by the hardened overtube  710  and the balloon  720 , thereby fixing the insertion route of the insertion section  110 . These steps S 3  and S 4  are referred to as first positioning. 
     In step S 5 , the endoscope  100  is connected to the motor, and the non-electrical driving is switched to electrical driving. The method of switching between the non-electrical driving and the electrical driving varies depending on the configuration of the drive mechanism. For example, when the medical system  10 , which is described later with reference to  FIG.  9   , is used, in steps  51  to S 4 , the forward/backward movement is non-electrically driven and the bending and the rolling rotation are electrically driven. In this case, the forward/backward movement may be switched from the non-electrical driving to the electrical driving by connecting the endoscope  100  to the forward/backward drive device  800 . Further, when the bending operation by non-electrical driving is enabled by providing a bending operation dial or the like capable of non-electrically performing the bending operation, the bending movement may be switched from the non-electrical driving to the electrical driving, for example, by connecting the connector  201  to the drive control device  200 . Alternatively, even if the motor is kept connected, the motor may be structured to be detachable by a clutch mechanism or the like, and the non-electrical driving may be switched to the electrical driving by the clutch mechanism. Step S 5  may be performed before step S 1 . For example, when the forward/backward movement is manually operated by electrical driving, the endoscope  100  may be connected to the motor before step S 1 . 
     In step S 6 , the drive control device  200  automatically positions the distal end section  130  at the papillary portion, and the operator confirms that the position of the distal end section  130  has been adjusted so that the papillary portion is captured at a predetermined position on the endoscope image. The drive control device  200  acquires an endoscope image from the video control device  500  and performs positioning of the distal end section  130  of the endoscope  100  based on the endoscope image. More specifically, the drive control device  200  controls the forward/backward movement, bending, or rolling rotation by electrical driving so that the papillary portion is captured at a position registered in advance on the endoscope image. The position registered in advance is, for example, the center of the image. The positioning can be performed so that the opening of the luminal tissue is captured at a position registered in advance. Further, the drive control device  200  may perform electrical driving control based on the endoscope image so that the camera faces directly the front of the papillary portion or so that the papillary portion is captured at an appropriate angle of view. The drive control device  200  may also adjust the angle of view in imaging the papillary portion by controlling the diameter of the balloon  720  by electrical driving based on the endoscope image so that the distance between the camera and the papillary portion can be changed without changing the line-of-sight direction of the camera. This step S 6  is referred to as second positioning. 
     In step S 7 , the operator inserts a cannula into the treatment tool channel through the insertion opening  190  to start cannulation into the biliary duct. 
     In  FIG.  6   , although the operation of the balloon in step S 3  and the hardening of the overtube in step S 4  are performed by non-electrical driving, they may be performed by electrical driving. In this case, the operator inputs an instruction from the operation device, and the drive control device  200  may inflate the balloon or harden the overtube by electrical driving using the instruction as a trigger. Alternatively, the drive control device  200  may perform an image recognition process for detecting the papillary portion from the endoscope image, and may automatically inflate the balloon or harden the overtube using the detection of the papillary portion from the endoscope image as a trigger. 
     According to the procedure flow described above, by inflating the balloon  720  before hardening the overtube  710  in step S 3 , the position of the distal end of the overtube  710  does not shift when the overtube  710  is hardened. Specifically, the distal end of the overtube  710  can be accurately positioned. In addition, by the first positioning in steps S 3  and S 4 , the insertion route of the insertion section  110  is held by the balloon  720  and the overtube  710 . As a result, in the second positioning in step S 6 , the forward/backward movement, bending, or rolling rotation of the endoscope  100  due to the electrical driving is easily transmitted from the base end side to the distal end of the insertion section  110 . This effect is described below with reference to  FIGS.  7   a    and  7   b.    
       FIGS.  7   a  and  7   b    show a comparison between a case without an overtube and a case with an overtube  710 . The forward movement of the insertion section  110  is described herein as an example. The forward movement of the insertion section  110  is achieved by pushing the insertion section  110  in the axial direction by a slider mechanism or the like, which is described later. As shown in  FIG.  7   a   , in the case where the insertion section  110  is not covered with the overtube  710 , when the base end side of the insertion section  110  is pushed in the axial direction, the force is absorbed by the deformation of the insertion section  110  and is not easily transmitted to the distal end of the insertion section  110 . This is because of the flexibility of the insertion section  110  and the stomach or the duodenum through which the insertion section  110  passes. As shown in  FIG.  7   b   , in the case where the insertion section  110  is covered with the hardened overtube  710 , when the base end side of the insertion section  110  is pushed in the axial direction, the insertion section  110  is moved forward in the overtube  710  using the hardened overtube  110  as a guide. As a result, the forward driving of the base end side is efficiently transmitted to the distal end section of the insertion section  110 . Also, for the bending or rolling rotation, the electrical driving from the base end side is efficiently transmitted to the distal end section of the insertion section  110  by holding the insertion section  110  by the overtube  710  and the balloon  720 . 
       FIG.  8    shows the vicinity of the distal end of an endoscope positioned by the overtube  710  and the balloon  720 . As shown in  FIG.  8   , the balloon  720  is fixed at a position slightly apart from the papillary portion to the pyloric side of the stomach. More specifically, the balloon  720  is positioned closer to the base end of the insertion section  110  than the base end of the bending section of the insertion section  110 . By combining such a balloon  720  with the overtube  710  having a variable hardness, the bending section exposed to the papillary portion side from the balloon  720  and the distal end section  130  can be freely operated without being fixed, and the electrical driving from the base end side can be efficiently transmitted to the distal end section  130  of the endoscope. 
     The endoscopic operation by the electrical driving is the forward and backward movement shown as arrow A 1 , a bending movement shown as arrow A 2 , or a rolling rotation shown as arrow A 3 . The forward movement is a shift toward the distal end side along the axial direction of the insertion section  110 , and the backward movement is a shift toward the base end side along the axial direction of the insertion section  110 . The bending movement is a movement by which the angle of the distal end section  130  is changed due to the bending of the bending section. The bending movement includes bending movements in two orthogonal directions, which can be controlled independently. One of the two orthogonal directions is referred to as the vertical direction and the other is referred to as the horizontal direction. The rolling rotation is a rotation about an axis of the insertion section  110 . 
       FIG.  8    shows an example in which the balloon  720  is attached to the distal end of the overtube  710  and the endoscope protrudes from the distal end of the overtube  710 . However, it is sufficient that the overtube  710  and the balloon  720  are configured so that a portion of the bending section beyond the base end can freely move. For example, it may also be arranged such that a soft tube with a constant hardness extends beyond the overtube with a variable hardness, and the balloon  720  is attached to the boundary thereof. In this case, although a part of the base end side of the bending section is covered with the soft tube, its movement is not hindered. 
     Detailed Configuration Example of Medical System 
       FIG.  9    shows a detailed configuration example of the medical system  10 . The medical system  10  is a system for observing or treating the inside of the body of a patient lying on an operating table T. The medical system  10  includes an endoscope  100 , a control device  600 , an operation device  300 , a treatment tool  400 , a forward/backward drive device  800 , and a display device  900 . The control device  600  includes a drive control device  200  and a video control device  500 . 
     The endoscope  100  is a device to be inserted into a lumen of a patient for the observation of an affected part. In this embodiment, the side to be inserted into a lumen of a patient is referred to as “distal end side” and the side to be attached to the control device  600  is referred to as “base end side” or proximal end side. The endoscope  100  includes an insertion section  110 , a connecting section  125 , an extracorporeal soft section  145 , and connectors  201  and  202 . The insertion section  110 , the connecting section  125 , the extracorporeal soft section  145 , and the connectors  201  and  202  are connected one another in this order from the distal end side. 
     The insertion section  110  is a portion to be inserted into a lumen of a patient, and is configured in a soft elongated shape. The insertion section  110  includes a bending section  102 , an extracorporeal soft section for connecting the base end of the bending section  102  and the connecting section  125 , and a distal end section  130  provided at the distal end of the bending section  102 . An internal route  101  is provided inside the insertion section  110 , the connecting section  125 , and the extracorporeal soft section  145 , and a bending wire passing through the internal route  101  is connected to the bending section  102 . When the drive control device  200  drives the wire via the connector  201 , the bending section  102  bends. Further, a raising base wire connected to a raising base provided at the distal end section  130  is connected to the connector  201  through the internal route  101 . As the drive control device  200  drives the raising base wire, the raising angle of the treatment tool  400  protruding from the side surface of the distal end section  130  is changed. The side surface of the distal end section  130  is provided with a camera, an illumination lens, and an opening of a treatment tool channel. An image signal line for connecting the camera and the connector  202  is provided in the internal route  101 , and an image signal is transmitted from the camera to the video control device  500  via the image signal line. The video control device  500  displays an endoscope image generated from the image signal on the display device  900 . 
     The connecting section  125  is provided with an insertion opening  190  of the treatment tool and a rolling operation section  121 . The treatment tool channel is provided in the internal route  101 , one end of which is open to the distal end section  130  and the other end of which is open to the insertion opening  190  of the treatment tool. An extension tube  192  extending from the insertion opening  190  to the operation device  300  is connected to the insertion opening  190 . The treatment tool  400  is inserted from an opening on the operation device  300  side of the extension tube  192 , and protrudes to the opening of the distal end section  130  via the insertion opening  190  and the treatment tool channel. The extension tube  192  may be omitted, and the treatment tool  400  may be inserted directly through the insertion opening  190 . The rolling operation section  121  is attached to the connecting section  125  so as to be rotatable about the axial direction of the insertion section  110 . By rotating the rolling operation section  121 , the insertion section  110  undergoes rolling rotation. As described later, the rolling operation section  121  can be electrically driven. 
     The forward/backward drive device  800  is a drive device for moving the insertion section  110  forward and backward by electrical driving. An extracorporeal soft section  145  is detachable from the forward/backward drive device  800 , and an insertion section  110  moves forward and backward when the forward/backward drive device  800  causes the extracorporeal soft section  145  to slide in the axial direction in a state in which the extracorporeal soft section  145  is mounted on the forward/backward drive device  800 . Although  FIG.  9    shows an example in which the extracorporeal soft section  145  and the forward/backward drive device  800  are detachable, there is no such limitation, and it may be arranged such that the connecting section  125  and the forward/backward drive device  800  are detachable. 
     The operation device  300  is detachably connected to the drive control device  200  via an operation cable  301 . The operation device  300  may communicate with the drive control device  200  through wireless communication instead of wired communication. When an operator operates the operation device  300 , a signal of the operation input is transmitted to the drive control device  200  via the operation cable  301 , and the drive control device  200  electrically drives the endoscope  100  to enable an endoscopic operation corresponding to the operation input based on the signal of the operation input. The operation device  300  has an operation input section having five or more channels corresponding to the forward and backward movement of the endoscope  100 , the bending movements in two directions and the rolling rotation, and the operation of the raising base. If one or more of these operations are not electrically driven, the operation input section may be omitted. Each operation input section includes, for example, a dial, a joystick, a D-pad, a button, a switch, a touch panel, and the like. 
     The drive control device  200  electrically drives the endoscope  100  by driving a built-in motor based on an operation input to the operation device  300 . Alternatively, when the motor is present outside the drive control device  200 , the drive control device  200  transmits a control signal to the external motor based on an operation input to the operation device  300 , thereby controlling the electrical driving. In addition, the drive control device  200  may drive a built-in pump or the like based on an operation input to the operation device  300 , thereby causing the endoscope  100  to perform air supply and/or suction. The air supply and/or suction are performed through an air supply/suction tube provided in the internal route  101 . One end of the air supply/suction tube opens to the distal end section  130  of the endoscope  100 , while the other end is connected to the drive control device  200  via the connector  201 . In addition, the treatment tool channel may be extended to the connector  201 , and the treatment tool channel may also be used as an air supply/suction tube. 
       FIG.  10    shows a detailed configuration example of a drive control device  200 . The drive control device  200  includes an image acquisition section  270 , a storage section  280 , a drive controller  260 , an operation reception section  220 , a wire drive section  250 , an air supply/suction drive section  230 , a communication section  240 , and an adapter  210 . 
     The adapter  210  includes an operation device adapter  211  to which the operation cable  301  is detachably connected, and an endoscope adapter  212  to which the connector  201  of the endoscope  100  is detachably connected. 
     The wire drive section  250  drives the bending movement of the bending section  102  of the endoscope  100  or the operation of the raising base of the treatment tool  400  based on the control signal from the drive controller  260 . The wire drive section  250  includes a bending movement motor for driving the bending section  102  of the endoscope  100  and a raising base motor for driving the raising base. The endoscope adapter  212  has a bending movement coupling for enabling coupling to the bending wire on the endoscope  100  side. When the bending movement motor drives the coupling, the driving force is transmitted to the bending wire on the endoscope  100  side. Further, the endoscope adapter  212  has a raising base coupling for enabling coupling to the raising base wire on the endoscope  100  side. When the raising base motor drives the coupling mechanism, the driving force is transmitted to the raising base wire on the endoscope  100  side. 
     The air supply/suction drive section  230  drives air supply and/or suction of the endoscope  100  based on a control signal from the drive controller  260 . The air supply/suction drive section  230  is connected to an air supply/suction tube of the endoscope  100  via the endoscope adapter  212 . The air supply/suction drive section  230  includes a pump or the like, and supplies air to the air supply/suction tube or sucks air from the air supply/suction tube  172 . 
     The communication section  240  (e.g., transceiver) communicates with a drive device provided outside the drive control device  200 . The communication may be wireless communication or wired communication. The drive device provided outside is a forward/backward drive device  800  for performing forward and backward movement, a rolling drive device for performing the rolling rotation, an overtube drive device for changing the hardness of the overtube  710 , a balloon drive device for changing the diameter of the balloon  720  or the like. 
     The drive controller  260  controls the forward and backward movement, the bending movement and the rolling rotation of the endoscope  100 , the raising angle of the treatment tool  400  made by the raising base, and the air supply and/or suction by the endoscope  100 . When the hardness control of the overtube  710  or the diameter control of the balloon  720  is electrically driven, the drive controller  260  performs the control thereof. The drive controller  260  is, for example, a processor such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a DSP (Digital Signal Processor), or the like. For example, the storage section  280  stores a computer-readable program, and the functions of the drive controller  260  are implemented as processes as the processor executes the program. However, the hardware of the drive controller  260  is not limited to that described above, and may be structured using circuits with various configurations. 
     The electric control performed by the drive controller  260  includes a manual mode in which the operator manually operates the electrical driving of the endoscope  100  or the like and an automatic control mode in which the electrical driving of the endoscope  100  or the like is automatically controlled based on an endoscope image. In the automatic mode of the present embodiment, the positioning step described with reference to  FIG.  2    is automated. In the automatic mode, at least one of the forward and backward movement, the bending movement, and the rolling rotation of the endoscope  100  may be automated. That is, the raising angle of the treatment tool  400  by the raising base, the hardness control of the overtube  710 , the diameter control of the balloon  720 , the air supply and/or suction of the endoscope  100 , or a part of the forward and backward movement, the bending movement or rolling rotation of the endoscope  100  may be manually operated. 
     First, the manual mode is described below. The operation reception section  220  receives an operation input signal from the operation device  300  via the operation cable  301  attached to the operation device adapter  221 . When the operation device  300  communicates with the drive control device  200  by wireless communication, the operation reception section  220  may be a wireless communication circuit. 
     The drive controller  260  controls the electrical driving based on an operation input signal from the operation reception section  220 . Specifically, when the bending operation is performed, the drive controller  260  outputs a control signal indicating the bending direction or the bending angle to the wire drive section  250 , and the wire drive section  250  drives the bending wire so that the bending section  102  bends in the bending direction or the bending angle. Also, when the forward and backward movement operation is performed, the drive controller  260  transmits a control signal indicating the forward/backward direction or the forward/backward movement amount to the forward/backward drive device via the communication section  240 , and the forward/backward drive device moves the extracorporeal soft section  140  forward or backward so that the endoscope  100  moves forward or backward in the forward/backward direction or the forward/backward movement amount. Further, when the rolling rotation operation is performed, the drive controller  260  transmits a control signal indicating the rolling rotation direction or the rolling rotation angle to the rolling drive device via the communication section  240 , and the rolling drive device performs rolling rotation of the insertion section  110  so that the endoscope  100  undergoes rolling rotation in the rolling rotation direction or at the rolling rotation angle. Similar controls are performed for other electrical driving. 
     Next, the automatic control mode is described below. The image acquisition section  270  is a communication interface for receiving image data of an endoscope image from the video control device  500  by wired communication or wireless communication. The image acquisition section  270  outputs image data of the received endoscope image to the drive controller  260 . 
     The storage section  280  stores a reference image of the papillary portion that serves as a reference for positioning with respect to the papillary portion. The reference image is an image in which the papillary portion is captured such that the opening of the luminal tissue appears at a predetermined position. The predetermined position is, for example, the center of the image, and corresponds to the “position registered in advance” described above. The storage section  280  may store a plurality of reference images corresponding to the various forms described with reference to  FIG.  3    or  FIG.  4   . The storage section  280  is a storage device such as a semiconductor memory or a magnetic storage device. The semiconductor memory may be a volatile memory such as a SRAM or a DRAM, or a nonvolatile memory such as an EEPROM. 
     The drive controller  260  controls the endoscopic operation or the diameter of the balloon  720  so that the position of the papillary portion in the endoscope image is brought close to the position of the papillary portion in the reference image. For example, the drive controller  260  extracts an image feature amount of the papillary portion from the endoscope image and the reference image, and determines the position of the papillary portion in the endoscope image based on the comparison result of the image feature amount. The drive controller  260  can control the endoscopic operation or the diameter of the balloon  720  so that the position of the opening of the luminal tissue on the endoscope image comes close to a predetermined position. For example, a reference image in which the opening of the luminal tissue is located at a predetermined position is stored in the storage section  280 . The drive controller  260  performs positioning of the opening of the luminal tissue by performing positioning of the papillary portion. Even in a case where the opening of the luminal tissue is closed and the opening cannot be recognized from the image, it is possible to perform the positioning so that the opening is present at a predetermined position in the image by performing positioning of the papillary portion. The storage section  280  may store the image feature amount extracted from the reference image, instead of the reference image. 
     The drive controller  260  may also control the endoscopic operation or the raising angle of the treatment tool  400  so that the distal end of the treatment tool  400  is directed toward the opening of the luminal tissue based on the endoscope image. Alternatively, the drive controller  260  may also control the endoscopic operation or the raising angle of the treatment tool  400  so that the distal end of the treatment tool  400  is directed toward the travelling direction of the biliary duct based on the endoscope image. For example, it may be arranged such that information on the travelling direction of the biliary duct is given to the reference image, and the distal end of the treatment tool  400  is controlled to be directed to the travelling direction of the biliary duct based on the information. Here, the travelling direction is a two dimensional direction on the endoscope image. That is, the endoscopic operation or the raising angle of the treatment tool  400  is controlled so that the travelling direction of the biliary duct and the direction to which the treatment tool  400  faces are substantially parallel to each other on the endoscope image. However, in a case where three dimensional information of the travelling direction of the biliary duct can be obtained from a CT image or the like, the control may be performed so that the travelling direction of the biliary duct and the direction to which the treatment tool  400  faces are substantially three dimensionally parallel. 
     Alternatively, the drive controller  260  may control the position of the opening of the luminal tissue in the endoscope image to be equal to the position registered in advance based on the result of the image recognition process using machine learning. More specifically, the storage section  280  stores a trained model, and the drive controller  260  performs the positioning control described above by performing a process based on the trained model. For example, the trained model receives input of an endoscope image and is trained to output information such as an endoscopic operation so that the position of the opening of the luminal tissue is located at a predetermined position in the endoscope image. Further, the trained model may be trained such that it receives input of an endoscope image and outputs information of the travelling direction of the biliary duct from the endoscope image. The drive controller  260  presumes information on an endoscopic operation or the like from an endoscope image by a process based on the trained model, and outputs a control signal for controlling the endoscopic operation or the raising angle of the treatment tool or the like to the wire drive section  250  or the like based on the information. In this example, the storage section  280  does not need to store the reference image or the image feature amount, and the “position registered in advance” of the opening of the luminal tissue is already reflected in the trained model by learning. 
     As described above, when cannulation into the biliary duct is performed, it is difficult to estimate the insertion position and the insertion direction of the cannula from the endoscope image of the papillary portion. In this regard, according to the present embodiment described above, in the second positioning after the first positioning by the overtube  710  or the like, the electrical driving of the endoscopic operation or the like is automatically controlled based on the endoscope image, so that the distal end section  130  of the endoscope  100  is automatically positioned with respect to papillary portion. As a result, it is not necessary to perform minute position adjustment by non-electric manual operation, and it is possible to assist the ERCP procedure performed by an inexperienced operator or the like. In addition, since the position of the papillary portion in the endoscope image is automatically controlled so as to be located at the position registered in advance by the automatic control, the operator can easily specify the insertion position and the insertion direction of the cannula from the endoscope image. For example, since the opening of the luminal tissue is automatically controlled so as to be at a predetermined position in the image, the operator can more easily grasp the position of the opening even when the opening cannot be visually recognized from the image. 
     Detailed Configuration Example of Each Part of Medical System  FIG.  11    is a schematic view of an endoscope  100  including a bending section  102  and a driving mechanism thereof An endoscope  100  includes a bending section  102 , a soft section  104 , and a connector  201 . The soft section  104  corresponds to the extracorporeal soft section  145  described above with reference to  FIG.  9   . In  FIG.  11   , the connecting section  125  is omitted. 
     The bending section  102  and the soft section  104  are covered with an outer sheath  111 . The inside of the tube of the outer sheath  111  corresponds to the internal route  101  in  FIG.  9   . The bending section  102  includes a plurality of bending pieces  112  and a distal end section  130  connected to the distal end of the bending pieces  112 . Each of the plurality of bending pieces  112  and the distal end section  130  is connected in series from the base end side to the distal end side by a rotatable connecting section  114 , thereby forming a multi joint structure. The connector  201  is provided with a coupling mechanism  162  on the endoscope side connected to a coupling mechanism on the drive control device  200  side. By attaching the connector  201  to the drive control device  200 , it is possible to electrically drive the bending movement. A bending wire  160  is provided in the outer sheath  111 . One end of the bending wire  160  is connected to the distal end section  130 . The bending wire  160  passes through the soft section  104  by penetrating through a plurality of bending pieces  112 , turns back in a coupling mechanism  162 , passes through the soft section  104  again, penetrates through the plurality of bending pieces  112 . The other end of the bending wire  160  is connected to the distal end section  130 . The driving force from the wire drive section  250  is transmitted to the bending wire  160  via the coupling mechanism  162  as the pulling force of the bending wire  160 . 
     As shown by the solid line arrow B 2 , when the upper wire in the figure is pulled, the lower wire is pushed, whereby the multiple joints of the bending pieces  112  are bent upward in the figure. As a result, as indicated by the solid line arrow A 2 , the bending section  102  is bent upward in the figure. When the lower wire in the figure is pulled as indicated by the dotted arrow B 2 , similarly, the bending section  102  is bent downward in the figure as indicated by the dotted arrow A 2 . As described with reference to  FIG.  8   , the bending section  102  can be bent independently in two orthogonal directions. Although  FIG.  11    shows a bending mechanism for one direction, two sets of bending wires can be provided, and each bending wire can be bent independently in two directions by being pulled independently by the coupling mechanism  162 . 
     Note that the mechanism for the electrically-driven bending is not limited to that described above. For example, a motor may be provided instead of the coupling mechanism  162 . Specifically, it may be arranged such that the drive control device  200  transmits a control signal to the motor via the connector  201 , and the motor drives the bending movement by pulling or relaxing the bending wire  160  based on the control signal. 
       FIGS.  12   a - 12   c    show a detailed configuration example of a forward/backward drive device  800 . The forward/backward drive device  800  includes a motor  816 , a base  818 , and a slider  819 . 
     As shown in  FIGS.  12   a  and  12   b   , the extracorporeal soft section  140  of the endoscope  100  is provided with an attachment  802  detachable from the motor  816 . As shown in  FIG.  12   b   , the attachment of the attachment  802  to the motor  816  enables electrical driving of forward/backward movement. As shown in  FIG.  12   c   , the slider  819  supports the motor  816  while enabling the motor  816  to move linearly with respect to the base  818 . The slider  819  is fixed to the operating table T shown in  FIG.  9   . As shown by arrow B 1 , the drive control device  200  transmits a forward or backward control signal to the motor  816  by wireless communication, and the motor  816  and the attachment  802  move linearly on the slider  819  based on the control signal. As a result, the forward and backward movement of the endoscope  100  shown by arrow A 1  in  FIG.  8    is achieved. Note that the drive control device  200  and the motor  816  may be connected by wired connection. 
       FIG.  13    is a perspective view of the connecting section  125  including a rolling drive device  850 . The connecting section  125  includes a connecting section main body  124  and a rolling drive device  850 . 
     The insertion opening  190  of the treatment tool is provided in the connecting section main body  124  and is connected to the treatment tool channel inside the connecting section main body  124 . The connecting section main body  124  has a cylindrical shape, and a cylindrical member coaxial with the cylinder is rotatably provided inside the connecting section main body  124 . The base end section of the intracorporeal soft section  145  is fixed to the outside of the cylindrical member, and the base end section serves as a rolling operation section  121 . As a result, the intracorporeal soft section  145  and the cylindrical member can rotate with respect to the connecting section main body  124  about the axial direction of the intracorporeal soft section  145 . The rolling drive device  850  is a motor provided inside the connecting section main body  124 . As shown by arrow B 3 , the drive control device  200  transmits a rolling rotation control signal to the rolling drive device  850  by wireless communication, and the rolling drive device  850  rotates the base end section of the intracorporeal soft section  145  with respect to the connecting section main body  124  based on the control signal, thereby causing rolling rotation of the intracorporeal soft section  119  ( 145 ?). As a result, the rolling rotation of the endoscope  100  shown by arrow A 3  in  FIG.  8    is achieved. The rolling drive device  850  may include a clutch mechanism, and the rolling rotation may be switched between non-electrical driving and electrical driving by the clutch mechanism. The drive control device  200  and the rolling drive device  850  may be connected by wired connection via a signal line passing through the internal route  101 . 
       FIGS.  14   a  and  14   b    show a detailed configuration example of a distal end section  130  of an endoscope including a raising base of a treatment tool.  FIG.  14   a    shows an external view of the distal end section  130 . An opening  131  of a treatment tool channel, a camera  132 , and an illumination lens  133  are provided on the side surface of the distal end section  130 . As shown in  FIG.  14 B , the direction parallel to the axial direction of the distal end section  130  is defined as z direction, the direction parallel to the line-of-sight direction of the camera  132  is defined as y direction, and the direction orthogonal to the z direction and they direction is defined as x direction.  FIG.  14   b    shows a cross-sectional view of the distal end section  130  in a plane that is parallel to the yz plane of the treatment tool channel and that passes through the opening  131  of the treatment tool channel. 
     The distal end section  130  includes a raising base  134  and a raising base wire  135 . The raising base  134  is swingable about an axis parallel to the x direction. One end of the raising base wire  135  is connected to the raising base  134 , while the other end is connected to the drive control device  200  via the connector  201 . As shown by arrow B 4 , the wire drive section  250  of the drive control device  200  pushes and pulls the raising base wire  135  to swing the raising base  134 , thereby, as shown by arrow A 4 , changing the raising angle of the treatment tool  400 . The raising angle is an angle of the treatment tool  400  protruding from the opening  131 . The raising angle can be defined, for example, by an angle formed by the treatment tool  400  protruding from the opening  131  and the z direction. 
       FIG.  15    shows a detailed configuration example of the treatment tool  400 . Herein, as an example of the treatment tool  400 , a cannula capable of operating bending of the distal end is shown. The treatment tool  400  includes a long-length insertion section  402  extending in the axial direction, a bending section  403  capable of bending movement, a first operation section  404  for operating the bending section  403 , and a second operation section  405  for inserting a contrast agent or a guide wire. 
     The insertion section  402  has a tube  421 , and the bending section  403  is connected to the distal end of the tube  421 . In  FIG.  15   , the distal end side of the tube  421  is enlarged. The tube  421  is also referred to as a sheath. The operator holds the tube  421  of the treatment tool  400  inserted into the treatment tool channel of the endoscope  100 , and pushes and pulls the tube  421  to move the treatment tool  400  forward and backward. 
     A connector  422  is connected to the base end of the tube  421 . The first operation section  404  and the second operation section  405  are connected to the connector  422 . The first operation section  404  includes a connecting tube  442 , one end of which is connected to the connector  422 , a first operation main body  441  connected to the other end of the connecting tube  442 , a grip  444  fixed to the base end of the first operation main body  441 , and a slider  443  provided movably forward and backward in the axial direction of the first operation main body  441 . Inside the tube  421 , the connector  422 , the connecting tube  442 , and the first operation main body  441 , a wire for connecting the bending section  403  and the slider  443  is provided. When the operator pulls the slider  443  while holding the grip  444 , the wire is pulled and the bending section  403  is bent. 
     The second operation section  405  includes a connecting tube  452 , one end of which is connected to the connector  422 , a second operation main body  451  connected to the other end of the connecting tube  452 , a first opening  453  opened in the axial direction of the connecting tube  452  on the base end side of the second operation main body, a second opening  454  opened to the outer surface of the second operation main body  451 , and a hook  455  provided on the second operation main body  451 . The hook  455  has elasticity and is formed in a substantially C-shape, and is used for locking the treatment tool  400  to the endoscope  100  or the like. The first opening  453  and the second opening  454  are connected to the tube  421  via the second operation main body  451 , the connecting tube  452 , and the connector  422 . By inserting a contrast agent or a guide wire from the first opening  453  or the second opening  454 , the contrast agent can be injected into the body or the guide wire can be inserted into the body from the distal end of the treatment tool  400 . 
     Although an example in which the treatment tool  400  is manually operated by non-electrical driving has been described herein, the operation of the treatment tool  400  may be operated by electrical driving. For example, using a method similar to the electrical driving of the endoscope  100 , it is possible to perform the forward/backward movement of the treatment tool  400 , the bending of the distal end, or the rolling rotation by electrical driving. 
       FIGS.  16   a  and  16   b    show a configuration example of the drive system  701  of the overtube  710 . As shown in  FIG.  16   a   , the drive system  701  includes an overtube  710  and an overtube drive device  715 . 
     The overtube  710  is structured such that its hardness is variable, its shape is variable during softening, and its shape is maintained during hardening. Although an example of using a shape memory polymer with its hardness changeable according to the temperature is shown herein, the method of varying the hardness is not limited to this example, and, for example, a structure in which the hardness is varied using a multi joint structure made of a plurality of bridge members connected in series may be used. As shown in  FIG.  16   a   , the overtube  710  includes an insertion section  705 s and an operation section  705   t . The operation section  705   t  is provided with a connecting section  705   a , and the overtube drive device  715  is connected via the connecting section  705   a.    
       FIG.  16   b    shows a cross-sectional view of the insertion section  705   s  in a cross section parallel to the insertion direction S. Although there are two tube walls in the cross section, the figure shows only one of them. The other wall has a similar structure. The insertion section  705   s  includes a tube member  705   p  and a shape memory polymer tube  705   i.    
     The shape memory polymer tube  705   i  is hardened when a fluid having a temperature lower than the glass transition temperature is supplied, and is softened when a fluid having a temperature higher than the glass transition temperature is supplied. The shape memory polymer tube  705   i  is covered with the tube member  705   p , and a supply path  705   k  and a collection path  705   b  connected to the distal end of the supply path  705   k  are provided between the shape memory polymer tube  705   i  and the inner wall of the tube member  705   p . The overtube drive device  715  is a fluid supply device including a pump and the like. The fluid supply device supplies a fluid of a predetermined temperature to the supply path  705   k  and collects the fluid from the collection path  705   b . The drive control device  200  transmits a control signal for controlling the hardness of the overtube  710  to the overtube drive device  715  by wireless communication, and the overtube drive device  715  changes the hardness of the overtube  710  by setting the temperature of the fluid based on the control signal. In  FIG.  16   b   , in the overtube  710 , the supply path  705   k  is located in the inner side and the collection path  705   b  is located in the outer side; however, the supply path  705   k  may be located in the outer side and the collection path  705   b  may be located in the inner side. Further, the drive control device  200  and the overtube drive device  715  may be connected by wired connection. 
     The mechanism for changing the hardness of the overtube by electrical driving is not limited to that described above. For example, it may be arranged such that a plurality of bridge members are connected in series, and the degree of contact between the bridge members are changed by electrical driving. Specifically, it may be arranged such that the overtube is softened by arranging adjacent bridge members so that they can slide and the overtube is hardened by arranging adjacent bridge members so that they are in contact with each other and cannot easily slide. 
       FIG.  17    shows a configuration example of the drive system  721  of the balloon  720 . The drive system  721  includes a balloon  720 , a connecting tube  722 , and a balloon drive device  725 . 
     The balloon  720  is made of an expandable member and is provided near the distal end of the overtube  710 . The balloon  720  has a doughnut shape and is disposed so as to surround the outer periphery of the distal end section of the overtube  710 . A balloon vent hole  723  is provided at the base end of the overtube  710 , and the balloon vent hole  723  and the balloon  720  are connected to each other via a pipeline (not shown). The balloon vent hole  723  and the balloon drive device  725  are connected to each other by a connecting tube  722 . The balloon drive device  725  includes a pump or the like, and inflates the balloon  720  by sending air to the balloon  720  through the connecting tube  722 , or deflates the balloon  720  by sucking air from the balloon  720 . The drive control device  200  transmits a control signal for controlling the diameter of the balloon  720  to the balloon drive device  725  by wireless communication, and the balloon drive device  725  inflates or deflates the balloon  720  based on the control signal, thereby controlling the diameter of the balloon  720 . The drive control device  200  and the balloon drive device  725  may be connected by wired connection. 
     Modifications 
     Some modifications are described below. Each modification can be combined with any of the embodiments described above. 
       FIG.  18    shows a first modification of the holding member. In this modification, a balloon  730  is provided at the distal end section  130  of the endoscope  100 . The diameter of the balloon  730  is variable by inflation and deflation. The diameter of the balloon  730  may be non-electrically controlled, or the diameter of the balloon  730  may be electrically controlled in a manner similar to that for the balloon  720 . The electrical driving may be manual operation or automatic control based on an endoscope image. By fixing the distal end section  130  of the endoscope  100  to the duodenum by the balloon  730 , the positional relationship between the distal end section  130  and the papillary portion can be stabilized during cannulation. As shown by arrow B 5 , by adjusting the diameter of the balloon  730 , it is possible to adjust the distance between the distal end section  130  and the papillary portion without changing the angle of the distal end section  130 . 
       FIG.  19    shows a second modification of the holding member. In this modification, a suction cap  740  is provided at the distal end section  130  of the endoscope  100 . A suction opening  741  is provided on the side surface of the suction cap  740  in the same direction as the line-of-sight direction of the camera or the like. By sucking air through the suction opening  741 , the intestinal wall of the duodenum is drawn toward the distal end section  130 . This allows adjustment of the distance between the distal end section  130  and the papillary portion. This suction may be performed by non-electrical driving or electrical driving. The electrical driving may be manual operation or automatic control based on an endoscope image. 
     As a third modification of the holding member, a basket may be used instead of the balloon  720  or  730 . By expanding or contracting the basket made of a plurality of bundled wires, a function similar to that of the balloon is achieved. As a fourth modification of the holding member, a grasper or a retractor may be provided at the distal end section  130  of the endoscope  100 . The grasper or the retractor grasps the intestinal wall of the duodenum and pushes or pulls the intestinal wall. As a result, the distal end section  130  is held in the duodenum, and the distance between the distal end section  130  and the papillary portion is adjusted. 
     Next, a description is given for a modification using endoscopes or the like having various lengths corresponding to individual differences of patients. Since each patient has a different organ structure, it is difficult to use the same endoscope, overtube, or attachment for all patients.  FIG.  20    shows an organ structure of a patient who had a gastric bypass surgery according to the Roux-en Y method, as an example of individual differences in organ structures. The Roux-en Y method is performed such that the stomach is divided into a bag connected to the esophagus and a bag connected to the duodenum, the ileum is connected to the bag connected to the esophagus, and the duodenum is connected in the middle of the ileum. The insertion distance from the mouth to the papillary portion differs between patients who had such a surgery and those who did not. 
     Therefore, by making the endoscope or overtube to be inserted into the body selectable for each patient by semi-reuse, single-use, or extension using attachment. Examples of reusable portions include the control device, the motor, the air supply/suction device, and the like. Examples of semi-reusable, single-use, or attachable portions include the endoscope, the treatment tool, the overtube, and the like. For the endoscope, the treatment tool, or the overtube, those different in length, balloon position, and the like are prepared. 
       FIG.  21    shows a modification of an operation device for manually operating an electric endoscope. Although an operation device  300  configured to be grasped by a user is shown in  FIG.  9   , a console-type operation device  320  may be used as shown in  FIG.  21   . The operation device  320  includes a monitor  325  for displaying an endoscope image, an operation section  321  operated by a right hand, an operation section  322  operated by a left hand, and one or more foot switches  323 . Both the operation sections  321  and  322  are capable of, for example, operation input in the vertical and horizontal directions. For example, the vertical/horizontal bending operation of the endoscope  100  is assigned to the vertical/horizontal operation of the operation section  321 , the forward/backward operation and the rolling rotation operation of the endoscope  100  are assigned to the vertical/horizontal operation of the operation section  322 , and the vertical operation of the raising base of the treatment tool  400  is assigned to the foot switch. The assignment of functions is not limited to this example. 
     As described above, the information obtainable in the ERCP procedure is only the endoscope image showing the papillary portion. Because there are individual differences in the form of the papillary portion and luminal tissue, it is difficult to specify the insertion position and the insertion direction of the cannula only based on the endoscope image. In order to more accurately assume the position of the opening and the travelling direction of the biliary duct, it is desirable to perform positioning so that the papillary portion is shown at a predetermined position in the image; however, it is difficult to adjust the position of the distal end of the endoscope because, for example, the operation performed at the base end side of the insertion section is not easily transmitted to the distal end section, or because the distal end section of the endoscope is easily displaced from the papillary portion. Although a robotic catheter system may be known for use in ERCP, the prior art does not disclose or suggest any of the above-mentioned problems or subject matter for solving them. 
     Therefore, the medical system  10  of the present embodiment includes the endoscope  100  and the control device  600 . In the endoscope  100 , the endoscopic operation is electrically driven, thereby capturing an endoscope image. The endoscopic operation is at least one of forward and backward movement of the insertion section  110 , the bending angle of the bending section  102  of the insertion section  110 , and the rolling rotation of the insertion section  110 . The control device  600  controls the electrically-driven endoscopic operation. After the first positioning for positioning the insertion section  110  with respect to the papillary portion of the duodenum is performed, the control device  600  controls the electrically-driven endoscopic operation based on the endoscope image, thereby performing the second positioning for positioning the distal end section  130  of the insertion section  110  with respect to the papillary portion. 
     According to the present embodiment, positioning of the insertion section  110  with respect to papillary portion can be done by the first positioning. Then, by performing the second positioning based on the positional relationship between the insertion section  110  thus positioned and the papillary portion, the endoscopic operation near the distal end can be more flexibly controlled by electrical driving. Further, by automatically controlling the electrical driving of the endoscopic operation or the like based on the endoscope image in the second positioning, the distal end section  130  of the insertion section  110  is automatically positioned with respect to the papillary portion. As a result, it is not necessary to perform minute position adjustment by non-electric manual operation, and it is possible to assist the cannulation procedure performed by an inexperienced operator or the like. 
     The endoscopic operation is described above with reference to  FIG.  8   . The papillary portion of the duodenum is described about with reference to  FIG.  1   . The first positioning and the second positioning are described above with reference to  FIG.  6   . 
     In the present embodiment, the medical system  10  may include a holding member that performs the first positioning of the insertion section  110  by holding the insertion section  110 . 
     According to the present embodiment, since the insertion section  110  is held by the holding member in the first positioning, the electrically-driven endoscopic operation is easily transmitted from the base end side to the distal end side of the insertion section  110  in the second positioning; further, the insertion section  110  is held so that the distal end section  130  of the endoscope  100  is prevented from displacing from the papillary portion. 
     The holding member corresponds to the overtube  710 , the balloon  720 , or both described with reference to  FIG.  5 ,  8 ,  16     a ,  16   b , or  17 , etc. Alternatively, the holding member may be the balloon  730  described in  FIG.  18   , the suction cap  740  described in  FIG.  19   , or the like. 
     In the present embodiment, the control device  600  may perform the second positioning for slightly adjusting the position of the distal end section  130  of the insertion section  110  by an endoscopic operation on a distal end side relative to the holding member holding the insertion section  110 . 
     According to the present embodiment, in the first positioning, the position of the distal end section  130  with respect to papillary portion is roughly adjusted, and the insertion section  110  is held by the holding member. As a result, the electrically-driven endoscopic operation is accurately performed, and the distal end section  130  is prevented from displacing from the papillary portion. Therefore, in the second positioning, the position of the distal end section  130  of the endoscope  100  can be slightly adjusted with respect to the papillary portion by the endoscopic operation on a distal end side relative to the holding member. 
     The term “on a distal end side relative to the holding member” means a portion of the holding member closer to the distal end than a portion to be hardened, fixed, etc. to restrict the endoscopic operation. This is described above with reference to  FIG.  8   . 
     Further, in the present embodiment, the control device  600  may perform the second positioning for controlling the electrically-driven endoscopic operation in a manner such that the image of the papillary portion is captured at a position registered in advance on the endoscope image. 
     According to the present embodiment, it is possible to obtain an endoscope image in which the papillary portion is located at the position registered in advance. As a result, the papillary portion appears in a familiar position and can thus be easily compared with those in the past cases or experiences. Therefore, the operator can easily judge the position of the opening of the luminal tissue and the travelling direction of the biliary duct by viewing the endoscope image. Further, since the positioning is performed by electrical driving, it is possible to obtain an endoscope image in which the papillary portion is located at a position registered in advance without requiring the operator to perform a minute operation. In addition, the control device  600  may perform the second positioning for controlling the electrically-driven endoscopic operation in a manner such that the image of the opening of the luminal tissue is captured at a position registered in advance in the endoscope image. The operator can grasp the position of the opening of the luminal tissue by viewing the endoscope image. For example, even in a case where the opening of the luminal tissue is closed in the image of the papillary portion and therefore is difficult to be visually recognized, the operator can presume that the opening of the luminal tissue is present at a predetermined position in the endoscope image. 
     The position registered in advance is described above, for example, with regard to  FIG.  6    or  FIG.  10    . 
     In the present embodiment, the papillary portion may include the opening of the luminal tissue. The opening of the luminal tissue may be an opening of the common duct in which the biliary duct and the pancreatic duct merge or an opening of the biliary duct, in the papillary portion of the duodenum. 
     In the papillary portion of the duodenum, there are various individual differences in the form of the papillary portion and the structure of the luminal tissue. According to the present embodiment, the positioning of the distal end section  130  of the endoscope  100  with respect to the papillary portion of the duodenum with various individual differences can be done by the first positioning and the second positioning. In addition, since the positioning of the papillary portion is automated, it is possible to assist the cannulation in the ERCP procedure. 
     The papillary portion of the duodenum, the opening of the luminal tissue, and their relationship are described above. 
     Further, in the present embodiment, the medical system  10  includes a treatment tool  400 . The treatment tool  400  is inserted from the insertion opening  190  of the treatment tool  400  of the endoscope  100 , and is raised inside the distal end section  130  to thereby protrude from the side surface of the distal end section  130 . The control device  600  performs the second positioning for controlling at least one of the endoscopic operation and the raising angle of the treatment tool  400  in a manner such that the treatment tool  400  faces toward the travelling direction of the biliary duct that is presumed from the endoscope image in which the image of the papillary portion is captured. 
     According to the present embodiment, at least one of the endoscopic operation and the raising angle of the treatment tool  400  is automatically controlled by the second positioning so that the treatment tool  400  faces toward the travelling direction of the biliary duct. As a result, the assumption of the travelling direction of the biliary duct, which is difficult due to individual differences in the papillary portion or the like, is automated, thereby assisting the ERCP procedure performed by an inexperienced operator or the like. 
     The raising of the treatment tool  400  is described above with regard to  FIGS.  14   a  and  14   b   . The control for directing the treatment tool  400  toward the travelling direction of the biliary duct is described, for example, with regard to  FIG.  10   . 
     Further, in the present embodiment, the holding member may include a first holding member for holding the insertion section  110  with respect to the organ in which the papillary portion is present. 
     Specifically, the first holding member may be a member that holds the insertion section  110  with respect to the duodenum in a state in which the distal end section  130  of the endoscope  100  reaches the papillary portion of the duodenum. 
     Further, the first holding member may be provided closer to the base end of the insertion section  110  than the base end of the bending section  102 . 
     Further, the first holding member may be a balloon  720  that is inflated and comes in contact with an organ, thereby holding the insertion section  110  with respect to the organ. 
     Since the insertion opening  190  is held in the organ by the first holding member, it becomes possible to perform the first positioning of the insertion section  110  with respect to the papillary portion in the organ, thereby flexibly controlling the endoscopic operation near the distal end by electrical driving in the subsequent second positioning. 
     The first holding member corresponds to the balloon  720  described above with reference to  FIG.  5 ,  8  or  17   , etc. Alternatively, the first holding member may be the balloon  730  described in  FIG.  18   , the suction cap  740  described in  FIG.  19   , or the like. 
     Further, in the present embodiment, the holding member may include a second holding member for holding the route of the insertion section  110  to the first holding member for holding the insertion section with respect to the organ. 
     The second holding member may be an overtube  710  with a variable hardness that holds the route of the insertion section  110  by being hardened. 
     Since the insertion opening  190  is held in the organ by the second holding member, it becomes possible to perform the first positioning of the insertion section  110  with respect to the opening of the luminal tissue in the organ, thereby flexibly controlling the endoscopic operation near the distal end section  130  by electrical driving in the subsequent second positioning. 
     The second holding member corresponds to the overtube  710  described with reference to  FIG.  5 ,  8 ,  16     a ,  16   b , or  17 , etc. The variable hardness of the overtube  710  is described above with reference to  FIGS.  16   a    and  16   b.    
     Further, in the medical system  10 , the electrical driving of the bending movement of the endoscope  100  is not limited to the structure of the present embodiment. For example, it may be structured such that an attachment equipped with an electric motor is detachably attached to a bending operation knob of a non-electrically-driven endoscope. The drive control device  200  and the attachment are structured to communicate with each other, and, upon reception of a bending control signal from the drive control device  200 , the attachment is driven to perform the bending. In this case, the manual control and the automatic control can be switched by attaching and detaching the attachment. It may also be arranged such that a handle capable of controlling the driving of the drive control device  200  is detachably attached to a motor for bending control corresponding to the drive control device  200 . In this case, the manual control and the automatic control can be switched by attaching and detaching the handle. 
     The present embodiment may be implemented as a cannulation method as follows. More specifically, the cannulation method uses the endoscope  100 . In the endoscope  100 , the endoscopic operation is electrically driven, thereby capturing an endoscope image. The endoscopic operation is at least one of forward and backward movement of the insertion section  110 , the bending angle of the bending section  102  of the insertion section  110 , and the rolling rotation of the insertion section  110 . The cannulation method includes a step of inserting the insertion section  110  of the endoscope  100  into a body. The cannulation method includes a step of performing the first positioning for positioning the insertion section  110  with respect to the papillary portion of the duodenum. The cannulation method includes, after the step of performing the first positioning, a step of performing the second positioning for positioning the distal end section  130  of the insertion section  110  with respect to the papillary portion by controlling electrically-driven endoscopic operation based on an endoscope image. The cannulation method includes, after the step of performing the second positioning, a step of performing cannulation from the papillary portion to the biliary duct. 
     In the present embodiment, in the step of performing the first positioning, the first positioning of the insertion section  110  may be performed by a holding member that holds the insertion section  110 . 
     Further, in the present embodiment, in the step of performing the second positioning, the position of the distal end section  130  of the endoscope  100  may be slightly adjusted by an endoscopic operation on a distal end side relative to the holding member holding the insertion section  110 . 
     Further, in the present embodiment, in the step of performing the second positioning, the electrically-driven endoscopic operation may be controlled so that the image of the papillary portion is captured at a position registered in advance in the endoscope image. 
     Further, in the present embodiment, the treatment tool  400  is inserted from the insertion opening  190  of the treatment tool  400  of the endoscope  100 , and is also raised inside the distal end section  130  to thereby protrude from the side surface of the distal end section  130 . In the step of performing the second positioning, it is possible to control at least one of the endoscopic operation and the raising angle of the treatment tool  400  in a manner such that the treatment tool  400  faces toward the travelling direction of the biliary duct that is presumed from the endoscope image in which the image of the papillary portion is captured. 
     The present embodiment may also be performed as a method of operating the medical system  10  as follows. More specifically, the method of operating the medical system  10  uses the endoscope  100 . In the endoscope  100 , the endoscopic operation is electrically driven, thereby capturing an endoscope image. The endoscopic operation is at least one of forward and backward movement of the insertion section  110 , the bending angle of the bending section  102  of the insertion section  110 , and the rolling rotation of the insertion section  110 . The method of operating the medical system  10  includes a step of performing the first positioning for positioning the insertion section  110  with respect to the papillary portion of the duodenum. The method of operating the medical system  10  includes, after the step of performing the first positioning, a step of performing the second positioning for positioning the distal end section  130  of the insertion section  110  with respect to the papillary portion by controlling electrically-driven endoscopic operation based on an endoscope image. In the method of operating the medical system  10 , the subject of each step is the medical system  10 . 
     In accordance with an aspect of the disclosed embodiments, a medical system can be provided. The medical system comprising: 
     a treatment tool configured to be inserted into an endoscope and including a sheath whose forward and backward movement is electrically driven; 
     an operation device for operating the electrically-driven forward and backward movement of the sheath; and 
     a controller comprising hardware, 
     the operation device comprising:
         a base;   an operation sheath disposed to be longitudinally slidable with respect to the base; and   a sliding operation detection sensor configured to detect a sliding operation of the operation sheath,       

     the controller being configured to control the electrically-driven forward and backward movement of the sheath of the treatment tool based on detected information of the sliding operation detected by the sliding operation detection sensor. 
     The present embodiment relates to an operation device in an electric medical system. The following describes an example where the medical system is applied to the ERCP procedures; however, the application of the medical system is not limited to ERCP and the medical system can be applied to any procedures including operations of moving a treatment tool of an endoscope forward and backward. 
       FIG.  22    is a diagram showing an operation of inserting a cannula when using non-electric endoscope and cannula. The operation section  1020  of the endoscope has a grip section  1021  and an insertion opening  1022  provided at the base end of the insertion section. The sheath  1031  of the cannula  1030  is inserted from the insertion opening  1022  into the treatment tool channel, and the distal end of the sheath  1031  protrudes from the distal end section of the endoscope toward the papillary portion. The operator holds the grip section  1021  of the operation section  1020  with one hand to operate the endoscope, and pushes and pulls the sheath  1031  with the other hand to move the sheath  1031  protruding from the distal end section of the endoscope forward and backward. 
     The operator inserts the cannula into the biliary duct, which is not shown in the endoscope image, while presuming the insertion position and the insertion direction of the cannula from an endoscope image in which the papillary portion is shown as in a to d in  FIG.  2   . At this time, as explained in  FIGS.  2  and  3   , it is difficult to appropriately insert the cannula into the biliary duct without, for example, inserting it into the pancreatic duct, because the papillary portion and the luminal tissue have a wide variety of forms. In order to properly perform this difficult operation, the sense of feel when pushing and pulling the non-electric sheath  1031  shown in  FIG.  22    by hand is important. 
     When the cannula is electrically driven, the electric cannula is operated by operating the operation device instead of manually operating the sheath  1031  of the cannula  1030  as shown in  FIG.  22   . Commonly used operation input sections include buttons, dials, D-pads, levers, and the like. However, these operation input sections are incapable of reproducing the sense of feel in pushing and pulling the non-electric sheath  1031  shown in  FIG.  22    by hand. For example, in the first place, these operation input sections are not configured to push and pull the sheath  1031 . Also, if it is a non-electric cannula, when the distal end of the cannula hits the narrowed portion or an obstacle, the force feedback is felt in the hand pushing the sheath  1031 ; however, such a force feedback is not appropriately performed in the operation input sections described above. Even if a kind of force feedback is made, it would not be a natural feedback because it is not an operation of pushing or pulling the sheath  1031 . 
     Medical System According to Another Embodiment 
     Therefore, the present embodiment provides an operation device capable of reproducing the sense of feel in pushing and pulling the sheath of the treatment tool by hand in an electric medical system, thereby assisting the ERCP procedures. The details of this structure are described below. 
       FIG.  23    shows a basic configuration example of a medical system  1010  according to the present embodiment. The medical system  1010  includes an endoscope  1100 , an overtube  1710 , a balloon  1720 , a treatment tool  1400 , a control device  1600 , and operation devices  1300  and  1301 . The following describes an example in which the endoscope and the treatment tool are electrically driven; however, the electric driving of the endoscope is not indispensable. Further, it is sufficient that at least the forward/backward movement of the treatment tool is electrically driven. 
     The overtube  1710  is a tube with a variable hardness that covers the insertion section  1110  of the endoscope  1100 . The balloon  1720  is provided near the distal end on the outer side of the overtube  1710 . The operator inserts the endoscope  1100  and the overtube  1710 , which is in a soft state, to the duodenum, inflates the balloon  1720  to fix a portion around the distal end of the overtube  1710  to the duodenum, and hardens the overtube  1710 . When the endoscope  1100  and the overtube  1710  are inserted into the body, at least the bending section of the insertion section  1110  is exposed from the distal end of the overtube  1710 . The bending section refers to a section structured to be bent at an angle corresponding to the bending operation in the vicinity of the distal end of the insertion section  1110 . The base end of the overtube  1710  is present outside the body. The base end side of the insertion section  1110  is exposed from the base end of the overtube  1710 . Although the example herein uses the overtube  1710  and the balloon  1720 , they may be omitted. 
     An insertion opening  1190  of the treatment tool is provided at the base end side of the insertion section  1110 , and a treatment tool channel for allowing the treatment tool  1400  to pass through from the insertion opening  1190  to the opening of the distal end section  1130  is provided inside the insertion section  1110 . The insertion opening  1190  of the treatment tool is also called a forceps opening; however, the treatment tool to be used is not limited to forceps. The operations of the treatment tool  1400 , which are forward and backward movement, bending of the distal end section, and rolling rotation, are electrically driven. The operation device  1310  is an operation device for operating the treatment tool  1400 , and is hereinafter also referred to as a treatment tool operation device. The operation device  1310  is connected to the drive control device  1200  via, for example, wireless communication. The drive control device  1200  receives an operation input signal from the operation device  1310  and controls the operation of the treatment tool  1400  based on the operational input signal. The operation device  1310  and the drive control device  1200  may be connected via wired connection using cables, connectors, etc. The detailed configuration example of the treatment tool  1400  is described later with reference to  FIG.  28   , and the detailed configuration example of the operation device  1310  is described later with reference to  FIG.  29    onward. 
     The endoscope  1100  is detachably connected to a control device  1600  using connectors  1201  and  1202 . The control device  1600  includes a drive control device  1200  to which the connector  1201  is connected, and a video control device  1500  to which the connector  1202  is connected. The drive control device  1200  controls the electrical driving of the endoscope  1100  via the connector  1201 . The drive control device  1200  is connected to the operation device  1300  for enabling manual operation of the electrical driving of the endoscope  1100 . Hereinafter, the operation device  1300  is also referred to as an endoscope operation device. The video control device  1500  receives an image signal from a camera provided at the distal end section  1130  of the endoscope  1100  via the connector  1202 , generates a display image from the image signal, and displays it on a display device (not shown). In  FIG.  6   , the drive control device  1200  and the video control device  1500  are shown as separate devices, but they may be structured as a single device. In this case, the connectors  1201  and  1202  may be integrated into a single connector. 
     The term “electrical driving” means that the treatment tool  1400  is driven by a motor or the like based on an electrical signal so as to control the treatment tool motion. The electrically-driven manual operation means that the operation device  1310  converts the operation input made by the operator from the operation device  1310  into an electrical signal, thereby driving the treatment tool  1400  by a motor or the like based on the electrical signal. The meaning of electrical driving and the meaning of electrically-driven manual operation are the same also for the endoscopic operation. 
       FIG.  24    shows a detailed configuration example of an electric treatment tool  1400 . Herein, as an example of the treatment tool  1400 , a cannula in which the forward and backward movement, the bending movement, and the rolling rotation are electrically driven is shown. However, it is sufficient that the forward and backward movement is electrically driven, and at least one of the bending movement and the rolling rotation may be non-electrically driven. The bending mechanism in the distal end section is not indispensable and may be omitted regardless of whether or not it is electrically driven or non-electrically driven. 
     The treatment tool  1400  includes a long-length insertion section  1402  extending in the axial direction, a bending section  1403  capable of bending movement, a bending driving section  1406  for electrically driving the bending section  1403 , and an operation section  1405  for inserting a contrast agent or a guide wire. 
     In  FIG.  24   , the distal end side of the tube  1421  is enlarged. The insertion section  1402  has a tube  1421 , and the bending section  1403  is connected to the distal end of the tube  1421 . In the example in  FIG.  24   , the tube  1421  corresponds to the sheath of the treatment tool. The tube  1421  may hereinafter also be referred to as a sheath. A force senser  1480  is provided in the vicinity of the distal end of the bending section  1403 . The force senser  1480  can be provided in areas not involved in the shape change by the bending movement.  FIG.  24    shows an example in which a single force senser is provided, but it is also possible to provide a plurality of force sensers. Note that the force senser  1480  may be omitted depending on the method of the force feedback, or if the force feedback is not performed. 
     An example of the force senser  1480  is a strain gauge. A strain gage is a mechanical sensor that measures the strain of an object on which the strain gage is provided. The distal end of the bending movement section  1403  is deformed as it comes in contact with organs, and the like, and the strain gauge detects the deformation, thereby detecting the stress of the contact. The strain gage has a thin insulator and a metal foil resistor provided on the insulator. When stress is applied to an object to which the strain gage is attached, the strain gage is deformed together with the object, and the resistance of the metal foil resistor is changed by the deformation. The drive control device  1200  measures this resistance, thereby detecting the stress. 
     The tube  1421  of the insertion section  1402  is detachable from the forward/backward drive device  1460 , and has a structure similar to, for example, the forward/backward drive device  1800  for use in endoscopes, which is described later with reference to  FIG.  37   . That is, the tube  1421  has an attachment detachable from the forward/backward drive device  1460 , and the attachment is attached to the motor of the forward/backward drive device  1460 , thereby enabling the forward/backward movement, i.e., in the direction of arrow E11 to be electrically driven. The drive control device  1200  transmits a forward or backward control signal to the motor by wireless communication, and the motor and the attachment move linearly in the axial direction of the tube  1421  based on the control signal, thereby moving the insertion section  1402  forward or backward. The drive control device  1200  and the forward/backward drive device  1460  may be connected by wired connection. 
     A connector  1470  is connected to the base end of the tube  1421 . The bending driving section  1406  and the operation section  1405  are connected to the connector  1470 . 
     The bending driving section  1406  includes a connecting tube  1482 , one end of which is connected to the connector  1470 , and a motor  1481  connected to the other end of the connecting tube  1482 . Inside the tube  1421 , the connector  1470 , and the connecting tube  1482 , a wire for connecting the bending section  1403  and the motor  1481  is provided. The drive control device  1200  transmits a bending movement control signal to the motor  1481  by wireless communication, and the motor  1481  drives the wire based on the control signal, thereby bending the bending section  1403 . For example, the bending movement of the bending section  1403  can be realized by a structure with a plurality of bending pieces, similarly in the bending section of the endoscope. The treatment tool  1400  in  FIG.  25    is capable of bending in one direction, i.e., the direction of arrow E 12 . Note that the drive control device  1200  and the motor  1481  may be connected by wired connection. 
     The operation section  1405  includes a connecting tube  1452 , one end of which is connected to the connector  1422 , an operation main body  1451  connected to the other end of the connecting tube  1452 , a first opening  1453  opened in the axial direction of the connecting tube  1452  on the base end side of the operation main body  1451 , a second opening  1454  opened to the outer surface of the operation main body  1451 , and a hook  1455  provided on the operation main body  1451 . The hook  1455  has elasticity and is formed in a substantially C-shape, and is used for locking the treatment tool  1400  to the endoscope  1100  or the like. The first opening  1453  and the second opening  1454  are connected to the tube  1421  via the operation main body  1451 , the connecting tube  1452 , and the connector  1422 . By inserting a contrast agent or a guide wire from the first opening  1453  or the second opening  1454 , the contrast agent can be injected into the body or the guide wire can be inserted into the body from the distal end of the treatment tool  1400 . 
     Inside the connector  1470 , a motor  1471  is provided to electrically drive the rolling rotation of the insertion section  1402 . The connector main body of the connector  1470  has a cylindrical shape, and a cylindrical member coaxial with the cylinder is rotatably provided inside the connector main body. The base end section of the tube  1421  of the insertion section  1402  is fixed to the outside of the cylindrical member. As a result, the tube  1421  and the cylindrical member are rotatable with respect to the connector main body about the axial direction of the tube  1421 . The drive control device  1200  transmits a rolling rotation control signal to the motor  1471  by wireless communication, and the motor  1471  rotates the base end section of the tube  1421  with respect to the connector main body based on the control signal, thereby allowing the insertion section  1402  to undergo rolling rotation, i.e., the direction of arrow E 13 . Note that the drive control device  1200  and the motor  1471  may be connected by wired connection. 
     Detailed Configuration Example of Treatment Tool Operation Device 
       FIG.  25    shows a first detailed configuration example of a treatment tool operation device. The operation device  1310  includes a base  1314 , an operation sheath  1315 , an arm section  1316 , and a sheath holding section  1317 . In  FIG.  26   , the axial direction of the operation sheath  1315  is referred to as the z1 direction, and the two directions that are orthogonal to the z1 direction and also orthogonal to each other are referred to as the x1 direction and the y1 direction, respectively. 
     The operation sheath  1315  is a sheath for use in operation and is provided separately from the sheath of the treatment tool  1400 . The operation sheath  1315  is a replica of the sheath of the treatment tool  1400 . However, the operation sheath  1315  may not be exactly the same as the sheath of the treatment tool  1400 . For example, the material, the diameter, the hardness, etc. of the operation sheath  1315  may be different from the material, the diameter, the hardness, etc. of the sheath of the treatment tool  1400 . The operation sheath  1315  does not necessarily have to be tubular, but can be a long cylindrical shape, or the like. 
     The base  1314  includes a first base  1311  that holds one end of the operation sheath  1315  and a second base  1312  that stores a controller  1331  for controlling the operation device  1310 . The second base  1312  may be omitted; in this case, the controller  1331  may be stored in the first base  1311 , or the like. 
     The operation sheath  1315  is slidable in the axial direction with respect to the first base  1311 . For example, the −z1 direction corresponds to the forward direction of the sheath of the treatment tool  1400 . In this case, when the operator slides the operation sheath  1315  in the −z1 direction, the sheath of the treatment tool  1400  moves forward, and when the operator slides the operation sheath  1315  in the +z1 direction, the sheath of the treatment tool  1400  moves backward. The sliding of the operation sheath  1315  and the forward/backward movement of the sheath of the treatment tool  1400  may be associated with each other in various ways. As an example, the amount of the forward/backward movement of the sheath of the treatment tool  1400  may be proportional to the sliding amount of the operation sheath  1315 . Alternatively, the treatment tool  1400  may continue to move forward when the operation sheath  1315  is pushed in by being slid in the −z1 direction and kept in that state. The same can be said for the backward movement. 
     The arm section  1316  is a rigid member for connecting the first base  1311  and the sheath holding section  1317  and supports the sheath holding section  1317  on the other end of the operation sheath  1315 . The arm section  1316  includes a first portion that is parallel to the operation sheath  1315 , a second portion extending in the x1-direction from one end of the first portion and connected to first base  1311 , and a third portion extending in the x1-direction from the other end of the first portion and supporting the sheath holding section  1317 . 
     The sheath holding section  1317  is a member that holds the other end of the operation sheath  1315  so that the operation sheath  1315  is slidable in the axial direction. The sheath holding section  1317  is provided with a hole that penetrates through it in the z1 direction. The operation sheath  1315  is inserted in the hole, and the operation sheath  1315  is slidable in the axial direction along the hole. 
     If the treatment tool  1400  has the bending driving section  1406  and the motor  1471  for the rolling rotation as shown in  FIG.  24   , the operation device  1310  may further include a rolling rotation operation section and a bending operation section by way of buttons, dials, levers, etc. Alternatively, the bending operation section and the rolling rotation operation section for the treatment tool may be provided in the operation device  1300  for endoscopes. 
     According to the present embodiment described above, the operator can operate the forward and backward movement of the electric treatment tool by pushing and pulling the operation sheath  1315 , which is a replica of the sheath of the treatment tool, in the axial direction. As a result, the sense of feel in the forward and backward movement of the non-electric treatment tool can be reproduced in the operation device of an electric treatment tool, thereby obtaining a natural sense of feel in operation in the procedure, such as cannulation. In addition, by performing the force feedback as described below, the hand sensation in operating the non-electric treatment tool can be reproduced in the operation device of an electric treatment tool. Also, by performing the force feedback with respect to the operation sheath  1315 , which is a replica of the sheath of the treatment tool, a natural force feedback similar to when operating a non-electric treatment tool can be obtained. 
       FIG.  26    shows a block configuration example of the medical system  1010 . The following describes a block configuration example of a portion of the treatment tool involved in the forward/backward movement operations. The medical system  1010  includes an operation device  1310 , a treatment tool  1400 , a drive control device  1200 , and a video control device  1500 . The operation device  1310  includes a controller  1331 , a sliding operation detection sensor  1332 , a force feedback section  1333 , and a communication section  1334 . The drive control device  1200  includes a drive controller  1260  and a communication section  1240  (e.g., transceiver). The treatment tool  1400  includes a forward/backward drive device  1460  and a force senser  1480 . 
     The sliding operation detection sensor  1332  and the force feedback section  1333  are stored in, for example, the first base  1311 , and the controller  1331  and the communication section  1334  are stored in, for example, the second base  1312 . However, there is no such limitation, and some or all of the controller  1331 , the sliding operation detection sensor  1332 , the force feedback section  1333  and the communication section  1334  may be stored in a section other than the base  1314 , for example, in the arm section  1316  or the like. 
     First, the operation of the medical system  1010  when the treatment tool  1400  moved forward or backward in response to the sliding operation is described below. 
     The sliding operation detection sensor  1332  detects the sliding operation of the operation sheath  1315 . Specifically, the sliding operation detection sensor  1332  detects the sliding direction and the sliding amount of the operation sheath  1315  in the axial direction. The sliding operation detection sensor  1332  is a force senser that detects the stress applied to the operation sheath  1315  by the sliding operation, or an optical sensor or the like that detects the sliding movement itself of the operation sheath  1315 . 
     The controller  1331  obtains information regarding the sliding direction and the sliding amount based on the detection signal of the sliding operation detection sensor  1332 , and transmits the information from the communication section  1334  to the communication section  1240  of the drive control device  1200 . The communication section  1334  of the operation device  1310  and the communication section  1240  of the drive control device  1200  are connected, for example, by wireless communication; however, they may also be connected by wired communication. 
     The drive controller  1260  generates a control signal for controlling the forward/backward movement direction and the forward/backward movement amount of the treatment tool  1400  based on the received information of the sliding direction and the sliding amount. The drive controller  1260  transmits the control signal to the forward/backward drive device  1460  of the treatment tool  1400  via the communication section  1240 . The forward/backward drive device  1460  causes the sheath of the treatment tool  1400  to move forward or backward so that the treatment tool  1400  moves forward/backward in the forward/backward movement direction or with the forward/backward movement amount. 
     Next, the operation of the medical system  1010  in performing the force feedback to the operation device  1310  is described below. 
     The force senser  1480  detects the stress applied to the distal end section of the treatment tool  1400  from organs or tissues. The drive controller  1260  receives a detection signal from the force senser  1480  via the communication section  1240 . The drive controller  1260  generates a control signal for the force feedback based on the detection signal of the force senser  1480 , and transmits the control signal to the communication section  1334  of the operation device  1310  via the communication section  1240 . The control signal for the force feedback is a signal indicating the intensity of the feedback, i.e., the intensity of the reaction force felt in the hand when sliding the operation sheath  1315 . 
     The controller  1331  of the operation device  1310  controls the force feedback section  1333  based on the control signal for the force feedback. The force feedback section  1333  generates a force in the direction opposite to the sliding direction of the operation sheath  1315 , thereby generating a reaction force against the sliding operation. The force feedback section  1333  is, for example, an electromagnetic coil, which is described later. However, the force feedback section  1333  may include a roller in contact with the operation sheath  1315  and a motor that rotates the roller, or may be a mechanical brake that provides resistance to the sliding operation by frictional force. The resistance due to the frictional force serves as the reaction force against the sliding operation. 
     By performing such a force feedback as described above, the operator can perform an insertion operation of the treatment tool while feeling the stress applied to the treatment tool, for example, when the treatment tool comes in contact with a tissue. 
     The controller  1331  is, for example, a processor such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a DSP (Digital Signal Processor), or the like. For example, the operation device  1310  includes a storage section (not shown), which stores a computer-readable program in which the functions of the controller  1331  are described. The functions of the controller  1331  are implemented as processes as the processor executes the program. The drive controller  1260  is, for example, a processor such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a DSP (Digital Signal Processor), or the like. For example, the drive control device  1200  includes a storage section (not shown), which stores a computer-readable program in which the functions of the drive controller  1260  are described. The functions of the drive controller  1260  are implemented as processes as the processor executes the program. 
       FIG.  27    shows a first detailed configuration example of the first base  1311 . The first base  1311  is provided with a spring  1318 , an electromagnetic coil  1333   a , and an optical sensor  1332   a.    
     The first base  1311  has a hole through which one end of the operation sheath  1315  penetrates in the z1 direction. The bottom of the hole in the first base  1311  and one end of the operation sheath  1315  are connected by the spring  1318 , which extends and contracts in the z1 direction. This hole and the spring  1318  enable the first base  1311  to hold the operation sheath  1315  while allowing it to be slidable. 
     One end of the operation sheath  1315  is made of a metal member  1315   a . The parts of the operation sheath  1315  other than the metal member  1315   a , i.e., the parts to be slid by hand, is made of a resin, for example. The electromagnetic coil  1333   a  is provided around the hole through which the metal member  1315   a  of the operation sheath  1315  passes, and the axis of the electromagnetic coil  1333   a  is parallel to the penetration direction of the hole. The electromagnetic coil  1333   a  corresponds to the force feedback section  1333 . The controller  1331  controls the current flowing in the electromagnetic coil  1333   a , and the electromagnetic coil  1333   a  exerts a force in the z1 direction on the metal member  1315   a  according to the current. This controls the force feedback. 
     The optical sensor  1332   a  is provided around the hole through which the metal member  1315   a  of the operation sheath  1315  passes, so that the light emission is directed toward the operation sheath  1315 . The optical sensor  1332   a  corresponds to the sliding operation detection sensor  1332 . The optical sensor  1332   a  detects the sliding direction and the sliding amount of the operation sheath  1315  by sensing the reflected light from the operation sheath  1315 . 
       FIG.  28    shows a second detailed configuration example of the first base  1311 . In  FIG.  28   , a strain gage  1332   b  is provided as the sliding operation detection sensor  1332 . The principle of the strain gage is as described in  FIG.  24   . The strain gage  1332   b  is disposed on one end of the operation sheath  1315  and is adhered, for example, to the surface of the metal member  1315   a . When the operation sheath  1315  is slid, the spring  1318  expands and contracts, and the metal member  1315   a  receives a stress from the spring  1318 . The strain gage  1332   b  detects the sliding direction and the sliding amount by detecting the stress.  FIG.  28    shows an example in which a single strain gage  1332   b  is provided; however, a plurality of strain gages may be provided on one end of the operation sheath  1315 . 
       FIG.  29    shows an example of control of force feedback. As described above, the drive controller  1260  controls the force feedback based on the detection signal of the force senser  1480  provided in the treatment tool  1400 . At this time, the drive controller  1260  increases the force feedback as the detection value of the force increases. That is, as the force exerted to the distal end of the treatment tool  1400  increases, the drive controller  1260  increases the reaction force against the sliding operation. 
     The means for detecting the reaction force exerted to the treatment tool  1400  from an organ or tissue is not limited to the force senser. For example, it is possible to detect the movement of the sheath of the treatment tool  1400 , and allow the drive controller  1260  to control the force feedback based on the movement. For example, in  FIG.  26   , the communication section  1240  of the drive control device  1200  receives an endoscope image from the video control device  1500 . It is assumed that a papillary portion and the sheath of the treatment tool  1400  are shown in this endoscope image. It is sufficient that only a part of the sheath of the treatment tool  1400  is shown in the endoscope image; the distal end of the treatment tool  1400  may be inserted in the biliary duct. The drive controller  1260  detects the forward/backward movement amount in the sheath&#39;s axial direction from the endoscope image, and controls the force feedback based on the forward/backward movement amount. 
       FIG.  30    shows an example of control of force feedback using an image. The drive controller  1260  increases the force feedback as the forward/backward movement amount detected from the image decreases. More specifically, the drive controller  1260  determines that the reaction force exerted to the distal end of the treatment tool  1400  due to narrowing of the biliary duct or the like is large when the forward/backward movement amount detected from the image is small even though the operation sheath  1315  is operated to slide in the forward direction, and increases the reaction force against the sliding operation. If the force feedback is controlled using an endoscope image, the force senser  1480  may not be provided in the treatment tool  1400 . 
       FIG.  31    shows a flow of ERCP procedure using the medical system of the present embodiment. In step S 1110 , the operator inserts an endoscope into the duodenum. In step S 1120 , the operator performs positioning of the distal end section of the endoscope with respect to the papillary portion, such as discussed above with regard to  FIGS.  1 - 21   . Specifically, the operator performs the positioning of the endoscope so that the camera of the endoscope is directly facing the papillary portion and the papillary portion is shown in the center of the field of view. 
     In step S 1130 , the operator activates the electrical driving of the treatment tool. Specifically, the operator inserts the treatment tool through the forceps opening of the endoscope to the distal end section, and after confirming that the distal end of the treatment tool has reached the distal end section of the endoscope, the operator activates the electrical driving of the treatment tool. Alternatively, the operator may insert the treatment tool through the forceps opening of the endoscope to the distal end section after activating the electrical driving of the treatment tool. 
     When the forward/backward drive device  1460  shown in  FIG.  24    is used, the electrical driving of the forward/backward movement is activated by attaching the attachment provided on the tube  1421  to the motor of the forward/backward drive device  1460 . Alternatively, the motor may be structured to be detachable by a clutch mechanism or the like, and the non-electrical driving may be switched to the electrical driving by the clutch mechanism. In this case, a button or switch, etc. may be provided in the operation device  1300  or the operation device  1310  to switch between the electrical driving and the non-electrical driving of the treatment tool, and, when the operator operates the button or switch, etc., the electrical driving and the non-electrical driving may be switched by the clutch mechanism. 
     In step S 1140 , the operator inserts a cannula from the papillary portion to the biliary duct by operating the operation device  1310  for the treatment tool and the operation device  1310  for the endoscope. Specifically, the operator adjusts the rolling rotation of the endoscope and the raising angle of the treatment tool so as to direct the cannula toward the travelling direction of the biliary duct and advance the cannula in the travelling direction, thereby inserting it into the biliary duct. The adjustment of the raising angle is described later with reference to  FIG.  38   , etc. 
     The operator injects a contrast agent into the cannula, captures a CT image of the biliary duct or the like, and inserts the guide wire from the cannula into the biliary duct. In step S 1150 , the operator deactivates the electrical driving of the treatment tool. The method of the deactivation is as described in step S 1130 . In step S 1160 , the operator non-electrically removes the cannula from the biliary duct and the endoscope. It may also be arranged such that step S 1160  is performed by electrical driving and the electrical driving of the treatment tool may be deactivated thereafter. 
     In the procedure described above, the endoscope may be operated either by electrical driving or non-electrical driving. The endoscope may also be switched between the electrical driving and the non-electrical driving at any timing during the procedure flow. 
       FIG.  32    shows a flow in the case of enabling/disabling functions based on the type of the treatment tool. The functions may be any function related to the treatment tool, e.g., the force feedback of the operation device  1310 . 
     In step S 1510 , the drive controller  1260  recognizes the type of the treatment tool inserted into the endoscope. Examples of the type of treatment tool include cannula, electronic knife, guide wire, basket, stent and the like. The type of the treatment tool may also be lineup, variation or grades of the same type of treatment tool. For example, it may be arranged such that the treatment tool is provided with a memory storing IDs, and the drive controller  1260  recognizes the type of the treatment tool by retrieving the ID from the memory. 
     In step S 1520 , the drive controller  1260  determines whether or not the treatment tool is of the predetermined type. If the type of the treatment tool is the predetermined type, in step S 1530 , the drive controller  1260  enables the function. If the type of the treatment tool is not a predetermined type, the drive controller  1260  disables the function in step S 1540 . 
       FIG.  33    shows a second detailed configuration example of the treatment tool operation device. In  FIG.  33   , the operation device  1310  has an operation input section for adjusting the raising angle. 
     Specifically, the first base  1311  corresponds to the stick part of the joystick. As shown by arrow F 11 , the first base  1311  and the second base  1312  are structured so that the first base  1311  can be tilted with respect to the second base  1312  in the direction crossing the axial direction of the operation sheath  1315 . As described later with reference to  FIG.  42   , the raising base that raises the treatment tool is electrically driven, and the drive control device  1200  controls the raising angle of the treatment tool in response to the above operation. 
       FIGS.  34   a  and  34   b    show a third detailed configuration example of the treatment tool operation device. In  FIGS.  34   a  and  34   b   , the operation device  1310  includes an attachment  1319  for detachably attaching the operation device  1310  to the operation device  1300  for the endoscope. 
     As shown in  FIG.  34   a   , the attachment  1319  is disposed on the side opposite to the side having the operation sheath  1315  in the arm section  1316 . The location of the attachment  1319  is not limited to this and can be anywhere other than the operation sheath  1315 . As shown in  FIG.  34   b   , by inserting the operation device  1300  for the endoscope into the attachment  1319 , the operation device  1310  for the treatment tool can be attached to the operation device  1300  for the endoscope. The operator holds the operation device  1300  for the endoscope with one hand and operates the operation device  1310  for the treatment tool with the other hand. 
     It may also be arranged such that the attachment  1319  and the operation device  1300  have connection terminals, and the connection terminals are connected to each other when the operation device  1300  is inserted into the attachment  1319 . Then, the operation device  1310  and the drive control device  1200  may establish communication connection with each other via the connection terminals, the operation device  1300 , and the cable connecting the operation device  1300  and the drive control device  1200 . 
     Detailed Configuration Example of Medical System 
       FIG.  35    shows a detailed configuration example of the medical system  1010 . Although an example in which the endoscope and the treatment tool are electrically driven is described herein, the endoscope may not be electrically driven. Further, it is sufficient that at least the forward/backward movement of the treatment tool is electrically driven. 
     The medical system  1010  is a system for observing or treating the inside of the body of a patient lying on an operating table T 1 . The medical system  1010  includes an endoscope  1100 , a control device  1600 , operation devices  1300  and  1310 , a treatment tool  1400 , forward/backward drive devices  1460  and  1800 , and a display device  1900 . The control device  1600  includes a drive control device  1200  and a video control device  1500 . 
     The endoscope  1100  is a device to be inserted into a lumen of a patient for the observation of an affected part. The side to be inserted into a lumen of a patient is referred to as “distal end side” and the side to be attached to the control device  1600  is referred to as “base end side”. The endoscope  1100  includes an insertion section  1110 , a connecting section  1125 , an extracorporeal soft section  1145 , and connectors  1201  and  1202 . The insertion section  1110 , the connecting section  1125 , the extracorporeal soft section  1145 , and the connectors  1201  and  1202  are connected one another in this order from the distal end side. 
     The insertion section  1110  is a portion to be inserted into a lumen of a patient, and is configured in a soft elongated shape. The insertion section  1110  includes a bending section  1102 , an extracorporeal soft section for connecting the base end of the bending section  1102  and the connecting section  1125 , and a distal end section  1130  provided at the distal end of the bending section  1102 . An internal route  1101  is provided inside the insertion section  1110 , the connecting section  1125 , and the extracorporeal soft section  1145 , and a bending wire passing through the internal route  1101  is connected to the bending section  1102 . When the drive control device  1200  drives the wire via the connector  1201 , the bending section  1102  bends. Further, a raising base wire connected to the raising base provided at the distal end section  1130  is connected to the connector  1201  through the internal route  1101 . As the drive control device  1200  drives the raising base wire, the raising angle of the treatment tool  1400  protruding from the side surface of the distal end section  1130  is changed. The side surface of the distal end section  1130  is provided with a camera, an illumination lens, and an opening of a treatment tool channel. An image signal line for connecting the camera and the connector  1202  is provided in the internal route  1101 , and an image signal is transmitted from the camera to the video control device  1500  via the image signal line. The video control device  1500  displays an endoscope image generated from the image signal on the display device  1900 . 
     The connecting section  1125  is provided with an insertion opening  1190  of the treatment tool and a rolling operation section  1121 . The treatment tool channel is provided in the internal route  1101 , one end of which is open to the distal end section  1130  and the other end of which is open to the insertion opening  1190  of the treatment tool. The treatment tool  1400  is inserted from the insertion opening  1190  of the connecting section  1125  and protrudes into an opening of the distal end section  1130  via the treatment tool channel. The rolling operation section  1121  is attached to the connecting section  1125  so as to be rotatable about the axial direction of the insertion section  1110 . By rotating the rolling operation section  1121 , the insertion section  1110  undergoes rolling rotation. Further, the rolling rotation can be electrically driven by providing a motor that rotates the rolling operation section  1121  in the connecting section  1125 . 
     The forward/backward drive device  1800  is a drive device for moving the insertion section  1110  of the endoscope  1100  forward and backward by electrical driving. An extracorporeal soft section  1140  is detachable from the forward/backward drive device  1800 , and an insertion section  1110  moves forward and backward when the forward/backward drive device  1800  causes the extracorporeal soft section  1140  to slide in the axial direction in a state in which the extracorporeal soft section  1140  is mounted on the forward/backward drive device  1800 . 
     The forward/backward drive device  1460  is a drive device for moving the sheath of the treatment tool  1400  forward and backward by electrical driving. The sheath is detachable from the forward/backward drive device  1460 , and, when the forward/backward drive device  1460  causes the sheath to slide in the axial direction in a state in which the sheath is mounted on the forward/backward drive device  1460 , the sheath moves forward and backward. Further, as described in  FIG.  24   , the bending or the rolling rotation may also be electrically driven. 
     The operation device  1300  of an endoscope is detachably connected to the drive control device  1200  via an operation cable  1301 . The operation device  1300  may communicate with the drive control device  1200  through wireless communication instead of wired communication. When an operator operates the operation device  1300 , a signal of the operation input is transmitted to the drive control device  1200  via the operation cable  1301 , and the drive control device  1200  electrically drives the endoscope  1100  to enable an endoscopic operation corresponding to the operation input based on the signal of the operation input. The operation device  1300  has an operation input section having five or more channels corresponding to the forward and backward movement of the endoscope  1100 , the bending movements in two directions and the rolling rotation, and the operation of the raising base. If one or more of these operations are not electrically driven, the operation input section may be omitted. Each operation input section includes, for example, a dial, a joystick, a D-pad, a button, a switch, a touch panel, and the like. 
     The operation device  1310  for the treatment tool is as described in  FIG.  25    to  FIG.  34   . 
     The drive control device  1200  electrically drives the endoscope  1100  or the treatment tool  1400  by driving a built-in motor based on an operation input to the operation devices  1300  and  1310 . Alternatively, when the motor is present outside the drive control device  1200 , the drive control device  1200  transmits a control signal to the external motor based on an operation input to the operation devices  1300  and  1310 , thereby controlling the electrical driving. In addition, the drive control device  1200  may drive a built-in pump or the like based on an operation input to the operation device  1300 , thereby causing the endoscope  1100  to perform air supply and/or suction. The air supply and/or suction are performed through an air supply/suction tube provided in the internal route  1101 . One end of the air supply/suction tube opens to the distal end section  1130  of the endoscope  1100 , while the other end is connected to the drive control device  1200  via the connector  1201 . In addition, the treatment tool channel may be extended to the connector  1201 , and the treatment tool channel may also be used as an air supply/suction tube. 
     Although the overtube  1710  and the balloon  1720  of  FIG.  23    are omitted in  FIG.  35   , the overtube  1710  and the balloon  1720  may be used also in  FIG.  35   . 
       FIG.  36    shows the vicinity of the distal end of an endoscope positioned at a papillary portion of duodenum.  FIG.  36    shows an example using the overtube  1710  and the balloon  1720 . 
     As shown in  FIG.  36   , the balloon  1720  is fixed at a position slightly apart from the papillary portion to the pyloric side of the stomach. More specifically, the balloon  1720  is positioned closer to the base end of the insertion section  1110  than the base end of the bending section of the insertion section  1110 . The endoscopic operation by the electrical driving is the forward and backward movement shown by arrow A 11 , a bending movement shown by arrow A 12 , or a rolling rotation shown by arrow A 13 . The forward movement is a shift toward the distal end side along the axial direction of the insertion section  1110 , and the backward movement is a shift toward the base end side along the axial direction of the insertion section  1110 . The bending movement is a movement by which the angle of the distal end section  1130  is changed due to the bending of the bending section. The bending movement includes bending movements in two orthogonal directions, which can be controlled independently. One of the two orthogonal directions is referred to as the vertical direction and the other is referred to as the horizontal direction. The rolling rotation is a rotation about an axis of the insertion section  1110 . The meaning is the same also for the forward and backward movement, the bending, and the rolling rotation of the treatment tool. 
       FIGS.  37   a - 37   c    show a detailed configuration example of a forward/backward drive device. Although the forward/backward drive device  1800  for an endoscopes is described herein as an example, the forward/backward drive device  1460  for a treatment tool has a similar structure. The forward/backward drive device  1800  includes a motor  1816 , a base  1818 , and a slider  1819 . 
     As shown in  FIGS.  37   a  and  37   b   , the extracorporeal soft section  1140  of the endoscope  1100  is provided with an attachment  1802  detachable from the motor  1816 . As shown in  FIG.  37   b   , the attachment of the attachment  1802  to the motor  1816  enables electrical driving of forward/backward movement. As shown in  FIG.  37   c   , the slider  1819  supports the motor  1816  while enabling the motor  1816  to move linearly with respect to the base  1818 . The slider  1819  is fixed to the operating table T 1  shown in  FIG.  35   . As shown by arrow B 11 , the drive control device  1200  transmits a forward or backward control signal to the motor  1816  by wireless communication, and the motor  1816  and the attachment  1802  move linearly on the slider  1819  based on the control signal. As a result, the forward and backward movement of the endoscope  1100  shown by arrow A 11  in  FIG.  40    is achieved. Note that the drive control device  1200  and the motor  1816  may be connected by wired connection. 
       FIGS.  38   a  and  38   b    show a detailed configuration example of a distal end section  1130  of an endoscope including a raising base of a treatment tool.  FIG.  38   a    shows an external view of the distal end section  1130 . An opening  1131  of a treatment tool channel, a camera  1132 , and an illumination lens  1133  are provided on the side surface of the distal end section  1130 . As shown in  FIG.  38   b   , the direction parallel to the axial direction of the distal end section  1130  is defined as z1 direction, the direction parallel to the line-of-sight direction of the camera  1132  is defined as y1 direction, and the direction orthogonal to the z1 direction and the y1 direction is defined as x1 direction.  FIG.  38   b    shows a cross-sectional view of the distal end section  1130  in a plane that is parallel to the y1z1 plane of the treatment tool channel and that passes through the opening  1131  of the treatment tool channel. 
     The distal end section  1130  includes a raising base  1134  and a raising base wire  1135 . The raising base  1134  is swingable about an axis parallel to the x1 direction. One end of the raising base wire  1135  is connected to the raising base  1134 , while the other end is connected to the drive control device  1200  via the connector  1201 . As shown by arrow B 14 , the wire drive section  1250  of the drive control device  1200  pushes and pulls the raising base wire  1135  to swing the raising base  1134 , thereby, as shown by arrow A 14 , changing the raising angle of the treatment tool  1400 . The raising angle is an angle of the treatment tool  1400  protruding from the opening  1131 . The raising angle can be defined, for example, by an angle formed by the treatment tool  1400  protruding from the opening  1131  and the z1 direction. 
     As explained above, in order to properly perform the procedure such as cannulation in ERCP, the sense of feel in pushing and pulling the sheath of the treatment tool by hand is important. However, when the treatment tool is electrically driven, the electric treatment tool is operated by operating the operation device instead of manually operating the sheath of the treatment tool by hand. Commonly used operation input sections include buttons, dials, D-pads, levers, and the like. However, these operation input sections are incapable of reproducing the sense of feel in pushing and pulling the sheath of the treatment tool by hand. Although the prior art may disclose a robotic catheter system, it does not disclose or suggest any of the above-mentioned problems or subject matter for solving them. 
     Therefore, the medical system  1010  of the present embodiment includes the treatment tool  1400 , the operation device  1300 , and the control device  1600 . The treatment tool  1400  is inserted into the endoscope  1100  and includes a sheath whose forward and backward movement is electrically driven. The operation device  1310  is used to operate the electrically-driven forward and backward movement of the sheath. The operation device  1310  includes the base  1314 , the operation sheath  1315  longitudinally slidable with respect to the base  1314 , and the sliding operation detection sensor  1332  for detecting the sliding operation of the operation sheath  1315 . The control device  1600  controls the electrically-driven forward and backward movement of the sheath of the treatment tool  1400  based on detected information of the sliding operation detected by the sliding operation detection sensor  1332 . 
     According to the present embodiment, the operator can operate the forward and backward movement of the electric treatment tool by pushing and pulling the operation sheath  1315 , which is a replica of the sheath of the treatment tool  1400 , in the axial direction. As a result, the sense of feel in causing the forward and backward movement of the non-electric treatment tool can be reproduced in the operation device  1310  of the electric treatment tool, thereby obtaining a natural sense of feel in operation in the procedure, such as cannulation. 
     The electric treatment tool is described, for example, with regard to  FIG.  24   . In this example, the sheath is the tube  1421 . The structure in which the forward and backward movement of the sheath is controlled based on the operation device, the base, the operation sheath, and the detected information of the sliding operation is described above. 
     Further, in the present embodiment, the operation device  1310  may include a force feedback section  1333  that performs force feedback with respect to the sliding operation. The control device  1600  may perform a force feedback control that causes the force feedback section to perform force feedback according to a reaction force that occurs when the distal end section of the treatment tool  1400  comes in contact with a tissue. 
     According to the present embodiment, the reaction force when the distal end section of the treatment tool  1400  comes in contact with a tissue is fed back to the operation sheath  1315 , thereby reproducing the hand sensation in operating a non-electric treatment tool in the operation device  1310  of an electric treatment tool. Also, by performing the force feedback with respect to the operation sheath  1315 , which is a replica of the sheath of the treatment tool  1400 , a natural force feedback similar to when operating a non-electric treatment tool can be obtained. 
     The force feedback is described above. Insofar as the force feedback is made according to the reaction force when the distal end section of the treatment tool comes in contact with a tissue, detection of the reaction force itself is not necessary. That is, it is sufficient that the physical quantity of a change caused by the reception of the reaction force from the tissue at the distal end section of the treatment tool is detected, and the force feedback is controlled based on the detection result. 
     Further, in the present embodiment, the treatment tool  1400  may also include the force senser  1480 , which is disposed in the distal end section of the sheath. The control device  1600  may perform the force feedback control based on detected force information detected by the force sensor  1480 . 
     According to the present embodiment, the reaction force when the distal end section of the treatment tool comes in contact with a tissue is detected by the force senser  1480 , and the force feedback control is performed based on the detected force information. That is, the reaction force received from the tissue at the distal end section of the treatment tool is directly detected as a sense of force. 
     The force feedback using the force senser is described with regard to  FIG.  26    and  FIG.  28   . 
     Further, in the present embodiment, the control device  1600  may also perform the force feedback control based on an endoscope image, which is an image showing the sheath captured by the endoscope  1100 . 
     According to the present embodiment, reception of a reaction force from a tissue at the distal end section of the treatment tool changes the movement of the sheath shown in the endoscope image, and the force feedback control is performed based on the change. That is, the reaction force received from a tissue at the distal end section of the treatment tool is indirectly detected from the endoscope image. 
     The force feedback using an endoscope image is described with regard to  FIG.  30   . 
     Further, in the present embodiment, the base  1314  may be disposed on one end of the operation sheath  1315 . The operation device  1310  may include the sheath holding section  1317 , which holds the operation sheath  1315  at the other end of the operation sheath  1315 . 
     According to the present embodiment, the base  1314  and the sheath holding section  1317  hold both ends of the operation sheath  1315 , allowing the operator to perform the sliding operation of the operation sheath  1315  provided between these ends. Further, holding both ends of the operation sheath  1315  stabilizes the operation sheath  1315 , allowing the operator to perform the operation more easily. 
     The sheath holding section is described with regard to  FIG.  25   . 
     Further, in the present embodiment, the control device  1600  may perform the force feedback control such that the sliding operation reaction force against the sliding operation increases as the reaction force increases. 
     In the case of operating a non-electric treatment tool by hand, the reaction force received from a tissue at the distal end section of the treatment tool is transmitted to the hand via the sheath. That is, the larger the reaction force, the greater the sense of force felt in the hand. According to the present embodiment, the larger the reaction force, the larger the sliding operation reaction force. This enables reproduction of the sense of feel in operating a non-electric treatment tool by hand. 
     The relationship between the reaction force received from a tissue at the distal end section of the treatment tool and the sliding operation reaction force is described with regard to  FIG.  29    and  FIG.  30   . 
     Further, in the present embodiment, the control device  1600  may also change the determination as to whether or not the force feedback control is performed, according to the type of the treatment tool  1400 . 
     According to the present embodiment, the force feedback can be enabled or disabled according to the type of the treatment tool. For example, it may be arranged such that the force feedback is enabled in a treatment tool with a force feedback function. It may also be arranged such that the force feedback is enabled or disabled depending on the type of the treatment tool, such as cannula, electronic knife, guide wire, basket, or stent, or depending on the lineup, variation, grades, etc. of the treatment tool. 
     The change of determination as to whether the force feedback control is performed according to the type of the treatment tool is described with regard to  FIG.  32   . 
     Further, in the present embodiment, the treatment tool  1400  may be a cannula. Further, in the present embodiment, the treatment tool  1400  may be a treatment tool to be inserted into a biliary duct or a pancreatic duct. The control device  1600  may electrically drive the sliding operation when the treatment tool  1400  is inserted into a biliary duct or a pancreatic duct after the distal end section  1130  of the endoscope  1100  is positioned at a papillary portion of duodenum. 
     During the cannulation in ERCP, by operating the forward and backward movement of an electric cannula using the operation device  1310  of the present embodiment, it is possible to reproduce the sense of feel in performing the forward and backward movement of a non-electric cannula. In the cannulation, since the cannula is inserted into the biliary duct, which is not shown in the endoscope image, the sense of feel in operation is important. According to the present embodiment, the sense of feel can be reproduced in an electric cannula. 
     The flow of ERCP procedure using an electric treatment tool is described with regard to  FIG.  31   . 
     Further, in the present embodiment, the operation sheath  1315  may be tiltable in a direction different from the sliding direction. The control device  1600  may change the direction of the raising base  1134  by which the treatment tool  1400  is raised when the operation sheath  1315  is tilted in a direction different from the sliding direction. 
     According to the present embodiment, the operation device  1310  for the treatment tool enables operation of the raising angle, together with the forward and backward movement of the treatment tool. In the cannulation, in some cases, the sheath is moved forward and backward while adjusting the raising angle; therefore, it is desirable to perform the movement and the adjustment by a single device, i.e., the operation device  1310 . 
     The operation device for the treatment tool capable of operating the raising angle is described with regard to  FIG.  33   . The operation sheath being the tiltable means that the operation sheath is tiltable with respect to the base or a part of the base. In the example in  FIG.  33   , since the first base  1311  is tiltable with respect to the second base  1312 , the operation sheath  1315  held by the first base  1311  is also tiltable with respect to the second base  1312 . 
     Further, in the present embodiment, the medical system  1010  may include an endoscope operation device  1300  for operating the electrically-driven endoscopic operation of the endoscope  1100 . The operation device  1310  may include an attachment  1319  for allowing the operation device  1310  for operating the treatment tool  1400  to be detachably attached to the endoscope operation device  1300 . 
     According to the present embodiment, the attachment  1319  allows the operation device  1310  for the treatment tool to be integrated with the operation device  1300  for the endoscope, thereby operating the endoscope and the treatment tool by the integrated operation device. Further, with the detachable structure, it becomes possible to change the operation device according to the type of the treatment tool, and attach it to the operation device  1300  for the endoscope for use. 
     Further, in the medical system  1010 , the electrical driving of the bending movement of the endoscope  1100  is not limited to the structure of the present embodiment. For example, it may be structured such that an attachment equipped with an electric motor is detachably attached to a bending operation knob of a non-electrically-driven endoscope. The drive control device  1200  and the attachment are structured to communicate with each other, and, upon reception of a bending control signal from the drive control device  1200 , the attachment is driven to perform the bending. In this case, the manual control and the automatic control can be switched by attaching and detaching the attachment. It may also be arranged such that a handle capable of controlling the driving of the drive control device  1200  is detachably attached to a motor for bending control corresponding to the drive control device  1200 . In this case, the manual control and the automatic control can be switched by attaching and detaching the handle. 
     According to an aspect of the disclosed embodiments, the following can be provided. 
     1. A medical system comprising: 
     a treatment tool configured to be inserted into an endoscope and including a sheath whose forward and backward movement is electrically driven; 
     an operation device for operating the electrically-driven forward and backward movement of the sheath; and 
     a controller comprising hardware, 
     the operation device comprising:
         a base;   an operation sheath disposed to be longitudinally slidable with respect to the base; and   a sliding operation detection sensor configured to detect a sliding operation of the operation sheath,       

     the controller being configured to control the electrically-driven forward and backward movement of the sheath of the treatment tool based on detected information of the sliding operation detected by the sliding operation detection sensor. 
     2. The medical system as defined in claim  1 , wherein 
     the operation device includes a force feedback section configured to perform force feedback in response to the sliding operation, and 
     the controller performs a force feedback control that causes the force feedback section to perform the force feedback according to a reaction force that occurs when a distal end section of the treatment tool contacts tissue. 
     3. The medical system as defined in claim  2 , wherein 
     the treatment tool includes a force senser disposed at a distal end section of the sheath, and 
     the controller performs the force feedback control based on detected force information detected by the force sensor. 
     4. The medical system as defined in claim  2 , wherein 
     the controller performs the force feedback control based on an endoscope image showing the sheath captured by the endoscope. 
     5. The medical system as defined in claim  2 , wherein 
     the controller performs the force feedback control such that a sliding operation reaction force against the sliding operation increases as the reaction force increases. 
     6. The medical system as defined in claim  2 , wherein 
     the controller changes determination as to whether or not to perform the force feedback control according to a type of the treatment tool. 
     7. The medical system as defined in claim  1 , wherein 
     the base is disposed on one end of the operation sheath; and 
     the operation device includes a sheath holding section for holding the operation sheath on an other end of the operation sheath. 
     8. The medical system as defined in claim  1 , wherein 
     the treatment tool is a cannula. 
     9. The medical system as defined in claim  1 , wherein 
     the treatment tool is configured to be inserted into a biliary duct or a pancreatic duct, and 
     the controller electrically drives the sliding operation when the treatment tool is inserted into the biliary duct or the pancreatic duct after positioning of a distal end section of the endoscope at a papillary portion of duodenum. 
     10. The medical system as defined in claim  1 , wherein 
     the operation sheath is tiltable in a direction different from the sliding direction, and the controller changes a direction of a raising base by which the treatment tool is raised when the operation sheath is tilted in the direction different from the sliding direction. 
     11. The medical system as defined in claim  1 , further comprising an endoscope operation device for operating an electrically-driven endoscopic operation of the endoscope, 
     wherein 
     the operation device includes an attachment that allows the operation device for operating the treatment tool to be detachable from the endoscope operation device. 
     Although the embodiments applied and the modifications thereof have been described above, the invention is not limited to the embodiments and the modifications thereof, and various modifications and variations in elements may be made in implementation without departing from the spirit and scope of the present disclosure. The plurality of elements disclosed in the embodiments and the modifications described above may be combined as appropriate to form various disclosures. For example, some of all the elements described in the embodiments and the modifications may be deleted. Furthermore, elements in different embodiments and modifications may be combined as appropriate. Thus, various modifications and applications can be made without departing from the spirit and scope of the invention. Any term cited with a different term having a broader meaning or the same meaning at least once in the specification and the drawings can be replaced by the different term in any place in the specification and the drawings.