Patent Publication Number: US-2015087898-A1

Title: Capsule endoscope magnetic control system

Description:
FIELD OF THE INVENTION 
     The present invention relates to capsule endoscope techniques, and, more particularly, to a capsule endoscope magnetic control system that controls the state of the capsule endoscope through the use of an external handheld controller. 
     BACKGROUND OF THE INVENTION 
     In the internal diagnosis and treatment of organisms, endoscope is a widely used tool. Early endoscopy involves installing a camera lens at the tip of a fiber-optic catheter of an endoscope, and inserting the camera lens and the fiber-optic catheter into the test object&#39;s mouth or anus. The camera captures the internal images of the test object and returns them back to an external device through the fiber-optic catheter. However, the stomach of a human body has many bends, and the camera lens is moved forward by pushing the fiber-optic catheter. This can cause discomfort in the test object during the examination process. 
     Later on, owing to the rapid development of medical equipment, early endoscopes with fiber-optic catheters are replaced by capsule endoscopes, which can be swallowed by the test object. Since there is no fiber-optic catheter, the test object does not feel discomfort. However, once the capsule endoscope is inside the test object, the movement of the capsule endoscope is achieved by gastrointestinal motility. In other words, the practitioner has no way of knowing the location of the capsule endoscope or moving it to a specific location. As a result, the capsule endoscopy may fail to obtain a desired image. Therefore, how to control the movement of a capsule endoscope has become a very important issue. 
     In recent years, large magnetic fields are created through instruments in order to guide the movements of the capsule endoscope and the image captured inside the test object. For example, a test object may lie on a large platform, and then the capsule endoscope is guided by moving a mechanical arm. However, such a device is bulky and costly and is limited by space when in use, and it is not easy and intuitive enough to use. 
     Furthermore, although the magnetically-controlled capsule endoscopy addresses some issues of the earlier endoscopy, there are still many problems to be overcome. First, the number of batteries that can be equipped in a capsule endoscope is limited by the size of the capsule endoscope, so the battery life is limited (usually eight hours), making it extremely inconvenient to use, since it usually takes up to two hours for a capsule endoscope to move to a desired shooting location by gastrointestinal motility after the endoscope is activated, and precisely when the endoscope reaches the desired location is difficult to calculate. Due to limited battery, the quantity and quality of the images captured are also under restrictions, that is, large number of high quality images cannot be provided to the practitioner. In addition, since the capsule endoscope and instrument are both implemented using permanent magnets, and therefore the size of the magnetic field created cannot be modified. If the attraction force is too large, the test object may feel discomfort since he/she can feel the presence of the capsule endoscope. On the other hand, if the attraction force is too small, insensitive control may occur. 
     Therefore, there is an urgent need to provide a control mechanism that addresses the issue of low internal power supply of the capsule endoscopes and provides effective capsule endoscopes. 
     SUMMARY OF THE INVENTION 
     In light of the foregoing drawbacks, an objective of the present invention is to provide a capsule endoscope magnetic control system that improves the controllability and operations of the capsule endoscope by changing the magnetic control method and the addition of wireless power supply mechanism. 
     In accordance with the above and other objectives, the present invention provides a capsule endoscope magnetic control system, which may include a control handle assembly and a capsule endoscope. The control handle assembly may include a magnetic control unit for generating a magnetic field, and a wireless power transmission unit for generating electromagnetic waves. The capsule endoscope is to be placed inside a test object, and may include a controlled unit, a wireless power receiving unit, an image capturing unit, a processing unit, and a wireless communication unit. The controlled unit is fixed to the outside of the capsule endoscope for moving and turning the capsule endoscope according to a change in the magnetic field. The wireless power receiving unit is used for sensing the electromagnetic waves and generating an induced current through the electromagnetic waves. The image capturing unit is used for capturing a state of the test object to generate an image data. The processing unit is used for receiving the image data and converting the image data into an image signal. The wireless communication unit is used for transmitting the image signal to the control handle assembly. The induced current generated by the wireless power receiving unit is used for providing power required for the operations of the image capturing unit, the processing unit and the wireless communication unit. 
     In an embodiment, the magnetic control unit includes a plurality of electromagnets, and the controlled unit includes a plurality of permanent magnets. 
     In another embodiment, the control handle assembly further includes a wireless receiving unit for receiving the image signal transmitted by the wireless communication unit of the capsule endoscope. In addition, the wireless receiving unit determines a distance between the control handle assembly and the capsule endoscope based on the strength of the image signal received. 
     In yet another embodiment, the control handle assembly further includes a display for displaying the image signal received by the wireless receiving unit. 
     The capsule endoscope magnetic control system described in the present invention may further include a control-box device electrically connected to the control handle assembly. The control-box device may include a power supply unit, a control logic unit, and an inverter. The power supply unit is used for supplying power to drive the operations of the magnetic control unit of the control handle assembly. The control logic unit is used for receiving a control signal from a control button on the control handle assembly to generate a feedback signal. The inverter is used for modifying the power provided by the power supply unit according to the feedback signal generated by the control logic unit in order to change the magnetic field and the magnetic polarity of the magnetic control unit of the control handle assembly. 
     In another embodiment, the control-box device may further include a control interface for controlling the power provided by the power supply unit and displaying the image signal received by the control logic unit. 
     In yet another embodiment, the control handle assembly may further include a cooling unit for dissipating heat generated by the magnetic control unit. In further another embodiment, the control handle assembly may further include a plurality of phase radars for detecting the angle and the location of the capsule endoscope. 
     Furthermore, in a specific implementation, the capsule endoscope may be egg-shaped or droplet-shaped with a narrower top and a wider bottom to facilitate movement of the capsule endoscope inside the test object. 
     Compared to the prior art, the capsule endoscope magnetic control system according to the present invention controls the capsule endoscope through changing the magnetic field of the electromagnets, which can be controlled compared to traditional permanent magnets of which the magnetic field cannot be controlled. Moreover, power required for the internal operations of the capsule endoscope can be generated by electromagnetic induction between the control handle assembly of the present invention and the capsule endoscope, thus power is not constrained as in the prior art. Furthermore, a plurality of phase radars can be provided on the control handle assembly to overcome the shortcoming that the location of the capsule endoscope cannot be determined during use in the prior art. With the capsule endoscope magnetic control system of the present invention, failing to detect desired images or poor image quality as a result of power issue of the capsule endoscope can thus be resolved. Moreover, practitioners may intuitively control and examine the images captured by the endoscope through the handheld controller, providing great help for the gastrointestinal endoscopy. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein: 
         FIG. 1  is a schematic diagram depicting a capsule endoscope magnetic control system in accordance with the present invention; 
         FIG. 2  is a schematic diagram illustrating a specific implementation of the capsule endoscope magnetic control system in accordance with the present invention; 
         FIG. 3  is a schematic diagram illustrating a control handle assembly of the capsule endoscope magnetic control system in accordance with the present invention; 
         FIG. 4  is a schematic diagram illustrating a capsule endoscope of the magnetic control system in accordance with the present invention; 
         FIG. 5  is a schematic diagram illustrating the capsule endoscope magnetic control system in accordance with the present invention when in use; 
         FIG. 6  is a schematic diagram depicting different arrangements of the electromagnets of the capsule endoscope magnetic control system in accordance with the present invention; 
         FIG. 7  is a schematic diagram illustrating another embodiment of the control handle assembly of the capsule endoscope magnetic control system in accordance with the present invention; and 
         FIGS. 8A and 8B  are schematic diagrams illustrating different shapes of the capsule endoscope of the capsule endoscope magnetic control system in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The present invention is described by the following specific embodiments. Those with ordinary skills in the arts can readily understand other advantages and functions of the present invention after reading the disclosure of this specification. 
     Referring to  FIG. 1 , a schematic diagram depicting a capsule endoscope magnetic control system  1  in accordance with the present invention is shown. The capsule endoscope magnetic control system  1  includes a control handle assembly  10  and a capsule endoscope  11 . The capsule endoscope  11  is to be swallowed by a test object, and a practitioner controls the capsule endoscope  11  through the use of the control handle assembly  10  in order to move the capsule endoscope  11  to a desired location and at an appropriate angle for image capturing. 
     The control handle assembly  10  includes a magnetic control unit  101  and a wireless power transmission unit  102 . The magnetic control unit  101  is used for generating a magnetic field to control the capsule endoscope  1 . In an embodiment, the control handle assembly  10  may be equipped with a driving motor for driving the magnetic control unit  101  to rotate, and in turn controlling the capsule endoscope  11 . In addition, the wireless power transmission unit  102  is used for generating electromagnetic waves to allow the capsule endoscope  11  to generate electrical energy through the induction principle. 
     The capsule endoscope  11  is to be placed in the test object. The capsule endoscope  11  includes a controlled unit  111 , a wireless power receiving unit  112 , an image capturing unit  113 , a processing unit  114 , and a wireless communication unit  115 . 
     The controlled unit  111  is fixed to the outside of the capsule endoscope  11 . The capsule endoscope  11  is moved or rotated by the controlled unit  111  according to the variations in the magnetic field created by the magnetic control unit  101 . More specifically, by changing the magnetic field created by the control handle assembly  10 , the controlled unit  111  is moved or rotated accordingly under the magnetic concept; that is, same poles attract each other and opposite poles repel each other. 
     Additionally, in order to avoid the shortcoming of an unchangeable magnetic field created by permanent magnets at the controlling end and the endoscope end, the magnetic control unit  101  comprises a plurality of electromagnets, and the controlled unit  111  comprises a plurality of permanent magnets. In other words, the magnetic control unit  101  can modify the size of its magnetic field to eliminate attraction force being too small or too large. 
     The wireless power receiving unit  112  is used for sensing the electromagnetic waves generated by the wireless power transmission unit  102  and inducing a current from the electromagnetic waves through electromagnetic induction. More specifically, the provision of the wireless power transmission unit  102  of the control handle assembly  10  and the wireless power receiving unit  112  of the capsule endoscope  11  addresses the issue of a short battery life of the capsule endoscope  11 . In this embodiment, electromagnetic waves are transmitted by the wireless power transmission unit  102 . Once sensing the electromagnetic waves, the wireless power receiving unit  112  induces a current through changes in the magnetic field, and the induced current can be used by the capsule endoscope  11 . 
     The image capturing unit  113  is used for capturing images  2  inside the test object and generating image data. Since the capsule endoscope  11  is used for photographing the test object, the image capturing unit  113  is provided in the capsule endoscope  11 . In this embodiment, in order to gain a more complete picture, the capsule endoscope  11  is provided with two camera lenses, one located in front of the capsule endoscope  11 , and the other located at the side of the capsule endoscope  11 , to help capturing a more complete image. 
     The processing unit  114  is used for receiving the image data captured by the image capturing unit  113  and converting the image data into image signals. The processing unit  114  may be a typical microcontroller that is capable of performing a variety of functions, such as calculating, storing information or inputting/outputting, and its functions will not be further described as it is a well-known component in this art. 
     The wireless communication unit  115  is used for sending the image signals generated by the processing unit  114  to the control handle assembly  10 . In this embodiment, the capsule endoscope  11  sends the image signals obtained in real time through the wireless communication unit  115 , without storing the signals internally. As such, image quality can be improved and shortage of storage is not an issue. In addition, the control handle assembly  10  and the capsule endoscope  11  communicate with each other through wireless transmission, eliminating the inconvenience of the early endoscope equipped with fiber-optic catheter. 
     From the above, in order to obtain complete images of a test object, the capsule endoscope  11  starts to take images once it enters into the test object, so it will need adequate power. Furthermore, the wireless communication unit  115  will transmit image signals to the control handle assembly  10  in real time; it also needs to consume a large amount of power. Therefore, in the present embodiment, the induced current is generated by the wireless power receiving unit  112  to provide power needed by the image capturing unit  113 , the processing unit  114 , the wireless communication unit  115  or other built-in components in the capsule endoscope  11  during operation, thereby addressing the problems of the prior-art capsule endoscopes. 
     Referring to  FIG. 2 , a schematic diagram illustrating a specific implementation of the capsule endoscope magnetic control system in accordance with the present invention is shown. As shown, in order to overcome the inconvenience of using the magnetic field of a bulky instrument to control the capsule endoscope, the present invention proposes the control handle assembly  10  to allow easy manipulation by the practitioner. The control handle assembly  10  is designed like a handle. In order to reduce the weight and volume of the control handle assembly  10 , in this embodiment, a control-box device  12  electrically connected with the control handle assembly  10  is provided in the capsule endoscope magnetic control system  1 . In this way, heavier or non-critical elements can be located in the control-box device  12 , so that the practitioner can easily manipulate the control handle assembly  10 . 
     The control-box device  12  can be connected to the control handle assembly  10  through a transmission line. In one example, the control-box device  12  includes a power supply unit  121 , a control logic unit  122 , and an inverter  123 . 
     The power supply unit  121  is used for providing power in order to drive the magnetic control unit  101  in the control handle assembly  10 . As mentioned earlier, the magnetic control unit  101  comprises a plurality of electromagnets. A magnetic field is created or changes in the magnetic field are created in the magnetic control unit  101  through the power provided by the power supply unit  121 . 
     The control logic unit  122  is used for receiving control signals sent from control buttons  105  on the control handle assembly  10  to generate a feedback signal. More specifically, the practitioner manipulates the control handle assembly  10  through the control buttons  105 . For example, the practitioner manipulates the driving motor in the control handle assembly  10  to rotate clockwise or anticlockwise, thereby changing the magnetic field of the magnetic control unit  101 . Thus, the control logic unit  122  will provide a feedback signal according to the control signals of the control buttons  105  to change the magnetic field of the magnetic control unit  101 . 
     The inverter  123  is used for modifying the power provided by the power supply unit  121  according to the feedback signal of the control logic unit  122  in order to change the magnetic field and the magnetic polarity of the magnetic control unit  101  of the control handle assembly  10 . As mentioned earlier, when the driving motor in the control handle assembly  10  rotates clockwise or anticlockwise, the magnetic field of the magnetic control unit  101  is changed, which in turn rotates or moves the controlled unit  111  of the capsule endoscope  11  as a result of changes in the magnetic field of the magnetic control unit  101 . 
     Moreover, the control-box device  12  further includes a control interface  124  for controlling the power provided by the power supply unit  121  and displaying the image signals received by the control logic unit  122  from the control handle assembly  10 . In an example, the control interface  124  and the power supply unit  121  can transmit signals between each other through a Universal Serial Bus (USB). The control interface  124  and the control logic unit  122  can be connected through an RS232 interface, and the control interface  124  may display real-time images in addition to controlling the power provided by the power supply unit  121 . 
     The control handle assembly  10  includes, in addition to the magnetic control unit  101  and the wireless power transmission unit  102 , a wireless receiving unit  103 , a display  104 , and the control buttons  105 . The wireless receiving unit  103  is used for receiving the image signals transmitted by the wireless communication unit  115  of the capsule endoscope  11 . Since there is no physical link between the control handle assembly  10  and the capsule endoscope  11 , the image signals transmitted by the wireless communication unit  115  is received by the wireless receiving unit  103  of the control handle assembly  10 , and the image signals received by the wireless receiving unit  103  can be not only displayed by the display  104 , but also returned back to the control-box device  12 . 
     The purpose of the display  104  is to enable the practitioner to observe images during the manipulation process in order to manipulate the movement or rotation of the control handle assembly  10 . However, in order to reduce the volume and weight of the control handle assembly  10 , the display  104  only displays coarser images. If finer images are needed, they are available on the control interface  124  of the control-box device  12 . In addition, the control buttons  105  allow the practitioner to easily change the magnetic field of the magnetic control unit  101  during operation. 
     The capsule endoscope  11  includes, in addition to the controlled unit  111 , the wireless power receiving unit  112 , the image capturing unit  113 , the processing unit  114  and the wireless communication unit  115 , an illumination unit  116 . The illumination unit  116  may be a light emitting diode for providing light required for the image capturing unit  113  to take images when the capsule endoscope  11  is inside the test object. Moreover, the image capturing unit  113  can comprise an image sensor  1131  and a lens  1132 , for example an image sensor  1131  equipped with a CMOS lens. 
     In addition, in order for the practitioner to have an idea of the distance between the control handle assembly  10  and the capsule endoscope  11 , the present invention further proposes that the strength of the image signals received by the wireless receiving unit  103  be determined in order to know the distance between the control handle assembly  10  and the capsule endoscope  11 . During wireless transmission, the distance affects the strength of the wireless signals, so the control handle assembly  10  can determine the distance between the control handle assembly  10  and the capsule endoscope  11  by determining the strength of image signals received by the wireless receiving unit  103 . This helps the practitioner to manipulate and reduces discomfort caused by large attraction force. 
     Referring to  FIG. 3 , a schematic diagram illustrating a control handle assembly of the capsule endoscope magnetic control system in accordance with the present invention is shown. In conjunction to  FIG. 2 , a control handle assembly  30  mainly includes a front end portion  306 , a grip portion  307 , a rear end portion  308 , and a connection cable  309 . The practitioner may hold the grip portion  307  during operation. Control buttons  305  on the grip portion  307  allow the driving motor in the control handle assembly  30  to change its rotation direction. The rear end portion  308  can be provided with a display  304  for displaying images to the practitioner during operation. 
     Moreover, the rear end portion  308  can return images through the connection cable  309  to the control-box device  12  of  FIG. 2 , or the control-box device  12  can provide power to the control handle assembly  30  through the connection cable  309 . In addition, the front end portion  306  allows the magnetic control unit  101  of  FIG. 2  to be provided therein, so the practitioner controls the capsule endoscope  11  of  FIG. 2  by changing the magnetic field of the magnetic control unit  101  in the front end portion  306 . 
     In other embodiments, the control handle assembly  30  further includes a cooling unit (not shown) that can be provided in the front end portion  306  for cooling the heat generated by the magnetic control unit  101 . The magnetic control unit  101  having electromagnets will generate heat energy during operation, and the heat is dissipated through a liquid such as oil. Furthermore, the liquid may be brought back to the control-box device  12  and heat dissipation is achieved through a fan (not shown) in the control-box device  12 . 
     Referring to  FIG. 4 , a schematic diagram illustrating a capsule endoscope of the capsule endoscope magnetic control system in accordance with the present invention is shown. As shown, a capsule endoscope  41  is encapsulated by a transparent optical cover  417  to protect the elements in the capsule endoscope  41  from being damaged inside the test object. The capsule endoscope  41  includes a controlled unit  411  having permanent magnets, and image capturing units  413  facing two different directions for taking images from different angles and an illumination unit  416 . The wireless power receiving unit  112 , the processing unit  114  and the wireless communication unit  115  described with respect to  FIG. 2  can be provided on a single chip inserted into the capsule endoscope  41 . 
     In an embodiment, the controlled unit  411  surrounds the periphery of the capsule endoscope  41 . It has a plurality of raised parts such that, when the controlled unit  411  rotates as a result of changes in magnetic field of the magnetic control unit  101  of  FIG. 2 , the capsule endoscope  41  is propelled by these raised parts. 
     Referring to  FIG. 5 , a schematic diagram illustrating the capsule endoscope magnetic control system in accordance with the present invention when in use is shown. After a capsule endoscope  51  (protected by an optical cover  517 ) is swallowed by a test object and reaches an organ  7  of the test object, the practitioner then manipulates the location and/or angle of the capsule endoscope  51  through a control handle assembly  50 . That is, through magnetic changes of the electromagnets in a front end portion  506  of the control handle assembly  50 , a controlled unit  511  of the capsule endoscope  51  is changed accordingly, i.e., the capsule endoscope  51  rotates around its shaft to change the angle of the shooting lens, or the controlled unit  511  rotates around the capsule endoscope  51  to change the direction of progression of the capsule endoscope  51 . The practitioner can look at the images directly from a display of the control handle assembly  50 . Regarding the electromagnets in the front end portion  506  of the control handle assembly  50 , they can be arranged in different ways to achieve different magnetic controls. 
     Referring to  FIG. 6 , a schematic diagram depicting different arrangements of the electromagnets of the capsule endoscope magnetic control system in accordance with the present invention is shown. In the left hand side of  FIG. 6 , a front end portion  606  of the control handle assembly is provided with several electromagnets  8  arranged in a one-dimensional manner, for example, their poles are in the following order: weak S pole, weak N pole, strong N pole, weak N pole, and weak S pole. When the front end portion  606  rotates as a result of the driving motor, the rotational direction of the capsule endoscope  51  shown in  FIG. 5  will be affected, allowing control of the movement of the capsule endoscope  51 . On the other hand, in the right hand side of  FIG. 6 , a front end portion  606 ′ of the control handle assembly is also provided with several electromagnets  8  arranged in a two-dimensional manner. When the front end portion  606 ′ rotates as a result of the driving motor, the rotational direction of the capsule endoscope  51  will be affected, also allowing control of the movement and direction of the capsule endoscope  51 . 
     Referring to  FIG. 7 , a schematic diagram illustrating another embodiment of the control handle assembly of the capsule endoscope magnetic control system in accordance with the present invention is shown. When the capsule endoscope is inside the test object, in order for the practitioner to readily know where the capsule endoscope is, the control handle assembly further includes a plurality of phase radars  9  for detecting the angle and the location of the capsule endoscope. As shown, the plurality of phase radars  9  are provided in a front end portion  706  of the control handle assembly for detecting the angle and the location of the capsule endoscope, thereby assisting the practitioner to more quickly find out where the capsule endoscope is. 
       FIGS. 8A and 8B  are schematic diagrams illustrating different shapes of the capsule endoscope of the magnetic control system in accordance with the present invention. The capsule endoscope proposed by the present invention is moved forward by the esophagus muscle in the esophagus. A conventional capsule endoscope usually takes the form of a capsule. Since its shape is similar to a cylindrical shape, this adversely affects the movement of the capsule endoscope in the esophagus. In this regard, the present invention further proposes that the capsule endoscope to be designed to be narrower towards the top and wider towards the bottom. After experiments in various angles, the angle of the tapered end of the capsule endoscope is preferably about 30°, that is, the opening angle of the narrower end is about 30°. 
     In  FIG. 8A , the capsule endoscope is designed to have an egg-shaped appearance. As shown, it can be designed with a maximum diameter of 20 mm. An intersection is specified as the intersection between the maximum vertical tangent line and the maximum diameter tangent line, and the distance between this intersection and the tip at the narrower end is 18.01 mm, while the distance between the intersection and the tip at the wider end is 10 mm. In actual use, the wider end can be swallowed first. This will facilitate the movement of the capsule endoscope in the esophagus. 
     In addition, in  FIG. 8B , the capsule endoscope is designed to have a water droplet shape. As shown, the maximum diameter is 12 mm. In terms of the appearance of water droplet, the maximum vertical distance can be 26 mm, but taking into consideration that a sharp end is hazardous, so the sharp structure at the narrower end is truncated, so yielding an overall maximum vertical distance of 24.05 mm. Similarly, in actual use, the wider end can be swallowed first. This will facilitate the movement of the capsule endoscope in the esophagus. 
     It should be noted that, regardless of a egg-shaped or a droplet-shaped design, the upper end (i.e., the narrower end) of the capsule endoscope can be wired or wireless, and the upper and lower ends needs to be rounded to have an overall smooth appearance to avoid damaging the wall of the gastrointestinal tract during examination. With the design of a tapered shape, the stress exerted upon the capsule endoscope when the esophagus contracts will be maximized, facilitating the movement of the capsule endoscope in the human body. 
     In summary, the capsule endoscope magnetic control system proposed by the present invention controls the capsule endoscope through changing the magnetic field of the electromagnets, which can be controlled compared to traditional permanent magnets of which the magnetic field cannot be controlled. Moreover, power required for the internal operations of the capsule endoscope can be generated by electromagnetic induction between the control handle assembly of the present invention and the capsule endoscope. This indirectly solves the problem that images cannot be taken throughout the whole process and image transmission issue due to a lack of power in the capsule endoscope. With the capsule endoscope magnetic control system of the present invention, power issue of the capsule endoscope can be easily solved, and practitioners may intuitively control and examine the images captured by the endoscope through the handheld controller, providing great help for the gastrointestinal endoscopy. 
     The above embodiments are only used to illustrate the principles of the present invention, and should not be construed as to limit the present invention in any way. The above embodiments can be modified by those with ordinary skill in the art without departing from the scope of the present invention as defined in the following appended claims.