Patent Publication Number: US-11638519-B2

Title: Systems and methods for treating prostate disorders

Description:
CROSS-REFERENCE TO PRIOR APPLICATIONS 
     This application is a divisional application of a U.S. patent application Ser. No. 16/010,483, filed on Jun. 17, 2018, entitled “Treating Prostate Disorders,” which claims priority of U.S. Patent Application No. 62/636,116, filed on Feb. 27, 2018, entitled “Treating Prostate Disorders,” which are hereby incorporated by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates to systems and methods for the treatment of prostatic disorders in men, more specifically, systems and methods for treating benign prostatic hyperplasia (BPH) using minimally invasive tools. 
     DESCRIPTION OF THE RELATED ART 
     The prostate is a gland surrounding the bladder neck and proximal urethra in men and releasing prostatic fluid. Benign prostatic hyperplasia (BPH), which consists of prostatic adenoma, is a noncancerous enlargement of the prostate and is common prostate condition in older men. It causes bladder outflow obstruction and lower urinary tract symptoms including voiding and storage symptoms. It can also cause dysfunction of the urinary bladder (hereinafter, shortly bladder), or kidney damage. 
     Traditionally, transurethral resection of prostate (TURP) has been considered as the gold standard transurethral surgery for treating BPH. Recently, several other surgical procedures, such as KTP laser vaporization, bipolar electrosurgery, Thulium laser enucleation, and Holmium laser enucleation of prostate (HoLEP) have been developed and have been popularized. Some of these newly developed procedures adopting enucleation technique may separate prostatic adenomas from the prostate, leaving only prostatic capsule. Large prostatic adenomas can be moved to the bladder cavity for later transurethral retrieval after they are cut into smaller pieces enough for them to be passed through the urethral lumen. For instance, HoLEP procedure, which is a minimally invasive surgical procedure for BPH, consists of two independent phases: enucleation of prostatic adenoma and subsequent morcellation of enucleated adenoma tissue(s).  FIGS.  1 A- 1 C  illustrate the first phase of the conventional HoLEP procedure, where the prostatic adenoma  110  that was enlarged due to BPH and blocking the flow of urine out of the bladder  100  is enucleated. (In  FIG.  1 A , the dotted area  102  is collectively referred to as prostate, where the prostate was enlarged due to BPH.) Typically, with the patient under general or spinal anesthesia, the surgeon inserts a resectoscope working element  109  combined with an endoscope sheath into the patient&#39;s body through the urethra. The operator uses the laser beam  108  emitting from the tip of the laser fiber accommodated in the resectoscope working element to enucleate the prostatic adenoma  110  from the prostate capsule  103 , leaving just the capsule  103  in place. The surgeon pushes the separated pieces of prostatic adenoma  110  into the bladder  100  so that the pieces of enucleated prostatic adenoma  104  are placed in the bladder  100 . In general, the pieces of enucleated prostatic adenoma is too big to pass through the urethra. Thus, to remove the pieces of enucleated prostatic adenoma  104  from the bladder, the surgeon inserts a morcellation device through the sheath of the endoscope into the patient&#39;s bladder, fragments the pieces of enucleated prostatic adenoma  104  and sucks the smaller tissue from the bladder  100  through a tube that is a part of the morcellation device. 
     Typically, the morcellation device is engaged into an endoscope. Also, the tip portion of the endoscope inserted into the patient bladder has a light source and a camera lens so that the surgeon can visually locate the pieces of enucleated prostatic adenoma  104  and the tip portion of the morcellation device during the procedure. One of the most significant dangers associated with the morcellation procedure is that the inner pressure of the bladder  100  may unexpectedly drop during the procedure, causing the bladder  100  to collapse. If the bladder shrinks, the tip of the morcellator may inadvertently touch and damage the inner wall of the bladder  100  with the sharp blade of the morcellation device, causing accidental perforation on the bladder wall  100 . Thus, it is important to ensure that the bladder remains fully distended during the procedure and to maintain a safe distance between the blade of the morcellation device and the bladder inner wall. 
     In the conventional morcellation procedure, an assistant has to continuously monitor the bladder distention by frequent manual palpation and notify the operating surgeon if the bladder is not full. Typically, during the procedure, the assistant palpate the patient&#39;s suprapubic area with a hand(s) at preset time intervals and, based on the sensation at the hand(s), determines whether the bladder is full or not. However, for obese patients or patients with small bladder, this technique may not provide accurate information of the bladder distention status due to the abdominal fat layer between the assistant&#39;s finger and the bladder. Also, if the assistant is not sufficiently experienced, he may not be able to determine the bladder status correctly, failing to properly report the bladder status to the operating surgeon. 
     During the morcellation phase of the surgery, the bladder may collapse for several reasons: the irrigation fluid container becomes empty, the tube from the irrigation fluid container to the bladder becomes blocked, the valve in the upstream side of the bladder becomes inadvertently closed, the valve on the downstream side of the bladder becomes inadvertently open, so on. In general, several assistants in the operation room need to carefully and continuously monitor the entire flow system to ensure that the bladder remains fully distended. As such, there is a need for systems and methods for real-time monitoring the bladder status during the BPH surgery and maintain a safe distance between the bladder inner wall and morcellation device to thereby obviate the inadvertent damages to the bladder while the work load on the assistants is reduced during the BPH surgery. 
     SUMMARY OF DISCLOSURE 
     In embodiments, a system for real-time controlling a pressure inside a bladder through an endoscope includes one or more processors and a memory that is communicatively coupled to the one or more processors. The distal end portion of the endoscope is configured to be located inside the bladder. The endoscope has an inlet port that is configured to allow fluid to enter the bladder through the inlet port and an outlet port that is configured to allow fluid in the bladder to exit the bladder through the outlet port. The memory stores one or more sequences of instructions, which when executed by one or more processors causes steps to be performed including: receiving a first signal from a first pressure sensor installed in a first fluid passageway that is in fluid communication with the inlet port of the endoscope; receiving a second signal from a second pressure sensor installed in a second fluid passageway that is in fluid communication with the outlet port of the endoscope; and based on at least one of the first and second signals, actuating a valve that is installed in the first fluid passageway of fluid so as to adjust a flow rate of fluid flowing into the bladder through the inlet port of the endoscope. 
     In embodiments, a method for real-time controlling a pressure inside a bladder through an endoscope include receiving a first signal from a first pressure sensor installed in a first fluid passageway that is in fluid communication with the inlet port of the endoscope. The distal end portion of the endoscope is configured to be located inside the bladder. The endoscope has an inlet port that is configured to allow fluid to enter the bladder through the inlet port and an outlet port that is configured to allow fluid in the bladder to exit the bladder through the outlet port. The method further includes: receiving a second signal from a second pressure sensor installed in a second fluid passageway that is in fluid communication with the outlet port of the endoscope; and based on at least one of the first and second signals, actuating a valve that is installed in the first fluid passageway of fluid so as to adjust a flow rate of fluid flowing into the bladder through the inlet port of the endoscope. 
     In embodiments, a system for real-time monitoring of bladder volume during a surgical procedure includes one or more processors and a memory that is communicatively coupled to the one or more processors. The memory stores one or more sequences of instructions, which when executed by one or more processors causes steps to be performed including: receiving information of a maximum volume of the bladder before the surgical procedure; receiving one or more ultrasound images from an ultrasonic scanner; based on the one or more ultrasound images, determining a volume of the bladder; comparing a maximum volume of the bladder to the determined volume of the bladder; and if a difference between the maximum volume and determine volume of the bladder exceeds a threshold, issuing a warning associated with the difference. 
     In embodiments, a morcellator for fragmenting a piece of tissue inside a bladder includes: a morcellation blade set having an outer blade and an inner blade that slidably engages the outer blade, the inner blade being configured to fragment a piece of tissue by reciprocating, oscillating or rotating relative to the outer blade; and a distance sensor disposed on the outer blade and configure to measure the distance between the outer blade and an inner wall of a bladder. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       References will be made to embodiments of the invention, examples of which may be illustrated in the accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in the context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments. 
         FIGS.  1 A- 1 C  illustrate the conventional HoLEP procedure that enucleates prostatic adenoma. 
         FIG.  2    shows a schematic diagram of a system for morcellation after enucleation of prostatic adenoma in patients with benign prostatic hyperplasia (BPH) according to embodiments of the present disclosure. 
         FIG.  3    shows a schematic diagram of a device for monitoring the status of bladder according to embodiments of the present disclosure. 
         FIG.  4 A  shows a schematic diagram of an ultrasonic scanner according to embodiments of the present disclosure. 
         FIG.  4 B  shows the orientations of planes along which the ultrasonic scanner in  FIG.  4 A  acquires two-dimensional images of the bladder according to embodiments of the present disclosure. 
         FIG.  4 C  shows an exemplary real-time ultrasonic image generated by the ultrasonic scanner in  FIG.  4 A  according to embodiments of the present disclosure. 
         FIG.  4 D  shows an exemplary real-time ultrasonic image generated by the ultrasonic scanner in  FIG.  4 A  according to embodiments of the present disclosure. 
         FIG.  5    shows an enlarged view of the endoscope sheath, working element and endoscope for morcellation procedure in  FIG.  2    according to embodiments of the present disclosure. 
         FIG.  6    shows a perspective view of a tip portion of the working element and endoscope for morcellation procedure in  FIG.  5    according to embodiments of the present disclosure. 
         FIG.  7    shows a cross sectional view of the tip portion of the working element and endoscope for morcellation procedure in  FIG.  6   , taken along the direction  7 - 7 , according to embodiments of the present disclosure. 
         FIG.  8    shows a perspective view of a blade set of a morcellator according to embodiments of the present disclosure. 
         FIG.  9 A  shows a cross sectional view of the blade set of the morcellator in  FIG.  8    according to embodiments of the present disclosure. 
         FIG.  9 B  shows a cross sectional view of the blade set of the morcellator in  FIG.  8    according to embodiments of the present disclosure. 
         FIG.  10    shows a flowchart of an exemplary process for controlling a bladder pressure according to embodiments of the present disclosure. 
         FIG.  11    shows a diagnosis table according to embodiments of the present disclosure. 
         FIG.  12    shows exemplary plots of pressure as a function of time according to embodiments of the present disclosure. 
         FIG.  13    shows a computer system according to embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the following description, for purposes of explanation, specific details are set forth in order to provide an understanding of the invention. It will be apparent, however, to one skilled in the art that the invention can be practiced without these details. Furthermore, one skilled in the art will recognize that embodiments of the present invention, described below, may be implemented in a variety of ways, such as a process, an apparatus, a system, a device, or a method on a tangible computer-readable medium. 
     Components shown in diagrams are illustrative of exemplary embodiments of the invention and are meant to avoid obscuring the invention. It shall also be understood that throughout this discussion that components may be described as separate functional units, which may comprise sub-units, but those skilled in the art will recognize that various components, or portions thereof, may be divided into separate components or may be integrated together, including integrated within a single system or component. It should be noted that functions or operations discussed herein may be implemented as components that may be implemented in software, hardware, or a combination thereof. 
     It shall also be noted that the terms “coupled” “connected” or “communicatively coupled” shall be understood to include direct connections, indirect connections through one or more intermediary devices, and wireless connections. 
     Furthermore, one skilled in the art shall recognize: (1) that certain steps may optionally be performed; (2) that steps may not be limited to the specific order set forth herein; and (3) that certain steps may be performed in different orders, including being done contemporaneously. 
     Reference in the specification to “one embodiment,” “preferred embodiment,” “an embodiment,” or “embodiments” means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention and may be in more than one embodiment. The appearances of the phrases “in one embodiment,” “in an embodiment,” or “in embodiments” in various places in the specification are not necessarily all referring to the same embodiment or embodiments. 
       FIG.  2    shows a schematic diagram of a system  200  for prostatectomy for benign prostatic hyperplasia (BPH) of a patient  201  according to embodiments of the present disclosure.  FIG.  5    shows an enlarged view of the working element and endoscope for morcellation procedure in  FIG.  2    according to embodiments of the present disclosure. As depicted, the system  200  may include: a computing device (or shortly device)  224  for controlling various components of the system; a display  226  having one or more screens for displaying various images, such as endoscope image  228  and ultrasound image  230  of the patient  201  on an operating table, and electrically coupled to the device  224 ; an ultrasound probe  218  disposed on the lower abdomen of the patient  201  and capturing ultrasound images of the bladder  204 ; an endoscope  211  having multiple ports for coupling various devices thereto; an endoscope sheath  209  including a slender tube that is partially inserted into the bladder  204  and prostate  203  through the urethra; an irrigation fluid container  216  for providing fluid for the bladder  204 ; a servo mechanism  292  secured to the irrigation fluid container  216  and operated by the computing device  224  to move in the vertical direction, to thereby adjust the hydraulic head of the fluid in the irrigation fluid container  216 ; and a pump  293  for injecting fluid into the bladder through the endoscope  211 . (In  FIGS.  2  and  5   , the shaded areas correspond to the endoscope  211 .) In embodiments, the ultrasound probe  218  may be attached to a control device, such as a robot arm  222 , that is controlled by a robot  220 . The robot  220  may be electrically coupled to and controlled by the computing device  224 . 
     In embodiments, the endoscope  211  may accommodate various working elements. For instance, a mechanical tissue morcellation device may be engaged into the endoscope  211  and endoscope sheath  209  so that the surgeon may fragment the large pieces of enucleated prostatic adenoma (or shortly pieces of tissue)  206  in the bladder  204  into smaller pieces of tissue.  FIG.  2    shows, for the purpose of illustration, a morcellation device that is engaged into the endoscope  211 . However, it should be apparent to those of ordinary skill in the art that other suitable types of working elements may be engaged into the endoscope  211  and endoscope sheath  209 , depending on the type of surgical procedures. In embodiments, the morcellation device (or shortly morcellator) in  FIG.  2    may be used to fragment large pieces of prostatic tissue generated by various laser enucleation procedures for BPH, such as Holmium laser enucleation of prostate (HoLEP), Thulium laser, KTP laser, and, using other various enucleation procedures using energy sources including plasma or electricity. 
     In embodiments, the morcellation device may include: a morcellator handpiece  210  that is manipulated by the surgeon to fragment and remove the pieces of tissue  206 ; an inner blade  254  (which also corresponds to  806  in the  FIG.  8   ) that reciprocates along the longitudinal axis  810  of the endoscope to fragment and remove the pieces of tissue  206 ; a connector  252  that connects the proximal end of the inner blade  254  (which also corresponds to  806  in  FIG.  8   ) to a flexible tube  250 . In embodiment, as described in conjunction with  FIGS.  9 A and  9 B , the fragmented prostatic tissue in the bladder  204  may be sucked into the distal end of the inner blade  254  and exit the flexible tube  250 , as indicated by an arrow  273 . (Hereinafter, the term distal end refers to an end that is located inside the bladder. Likewise, the term proximal end refers to an end that is located outside the patient body and near the operating surgeon.) In embodiments, the morcellator handpiece  210  may have an electrical power line  205  that provides electrical power to drive the inner blade  254 . 
     In embodiments, an endoscope camera  212  may be attached to the endoscope  211 . As explained in conjunction with  FIG.  6   , a lens  604  and a visible light source  606  may be disposed at the distal end of the endoscope sheath  209  and electrically coupled to the endoscope camera  212 . In embodiments, a light cable  270  may be coupled to the endoscope  211  and, in turn to the light source  606 . In embodiments, the light provided through the light cable  270  may exit the light source  606  to illuminate the area nearby the distal end of the endoscope sheath  209 . Using the lens  604 , the endoscope camera  212  may capture the images of the pieces of tissue  206  and the tip of the morcellator, and send the captured image to the computing device  224 . In embodiments, the computing device  224  may process the received image and display the endoscope image  228  on the display screen  226 . In embodiments, the surgeon may manipulate the morcellator handpiece  210  while watching the endoscope image  228  during the morcellation procedure. 
     In embodiments, the endoscope  211  may include multiple stopcocks that regulate the fluid flow into or out of bladder. For instance, the endoscope  211  may include an inflow stopcock  506  that may be connected to the inflow tube  213  extending from the irrigation fluid container  216 . As explained in conjunction with  FIG.  7   , the endoscope sheath  209  may be in the form of a slender tube and include an inflow passageway of the irrigation fluid that extends from the inflow stopcock  506  to the bladder  204 . In embodiments, the space between the outer wall of the telescope  603  and the inner wall of the endoscope sheath  209  may form an inflow passageway through which the inflow  681  enters the bladder. 
     In embodiments, the endoscope  211  may include outflow stopcock  504  that may be connected to a drain tube  221 . Depending on the type of procedure, the surgeon may operate the outflow stopcock  504  so that the flow rate of the fluid exiting from the bladder may be controlled. In embodiments, a flow meter  214  may be disposed on the inflow tube  213  and measure the rate of flow into the bladder  204  through the endoscope  211 . In embodiments, the flow meter  214  may be electrically coupled to the computing device  224 . In embodiments, the flow meter  214  may sense/detect the flow through the inflow tube  213 . 
     It is important to monitor the bladder distention  204  continuously in real-time during the morcellation procedure so as to maintain a safe distance between the sharp blade of the morcellator and the inner wall of the bladder. In embodiments, the real-time monitoring may be performed to ensure that the bladder remains fully distended during the morcellation procedure. Since the variation in the bladder volume is closely related to the change in the pressure of the fluid inside and outside the bladder  204 , the pressure of the fluid may be measured at various locations. In embodiments, one or more of three pressure sensors may be used to measure the pressure of fluid: (1) an inflow-side pressure sensor  215  to measure the pressure of fluid entering the bladder; (2) a pressure sensor ( 804  in  FIG.  8   ) located near the distal end of the morcellator or distal end of endoscope sheath  209  to measure the pressure inside the bladder  204 ; and (3) an outflow-side pressure sensor  219  to measure the pressure of fluid exiting the bladder. 
     In embodiments, both the outflow stopcock  504  and the outflow valve  217  may be closed all the time during morcellation so that the fluid from the bladder may shut down during morcellation. In embodiments, during the morcellation procedure, the outflow stopcock  504  may be open and the outflow valve  217  may be closed for the outflow-side pressure sensor  219  to monitor bladder pressure. In such a case, the fluid inside the bladder  204  may exit the flexible tube  250  along with the fragmented tissue. Also, as described in conjunction with  FIG.  7   , the pressure measured by the outflow-side sensor  219  may indicate the pressure inside the bladder  204  if the outflow valve  217  is closed. 
     In embodiments, the device  224 , and one or more of the sensors  215 ,  219 , and  804  may form a system to regulate the flow into the bladder, to thereby control the bladder pressure. For instance, if the bladder pressure measured by the inflow-side sensor  215  is below a preset lower limit, a warning message, such as “bladder filling needed,” may be issued to the surgeon by the speaker  312 . 
     In embodiments, one or more of the pressures measured by the sensors  215 ,  219 , and  804  may be displayed on the display screen  226 . For instance, as shown in  FIG.  2   , two pressures  232  measured by the sensors  215  and  219  may be displayed on the display screen  226 . 
     Based on the measured pressures, the computing device  224  (more specifically, the processor  302  in  FIG.  3   ) may provide warning signals for the surgeon so that the surgeon may recognize the problem associated with the fluid flow and take proper remedial steps. For instance, if the pressure at the inflow-side sensor  215  is normal and the pressure at the outflow-side sensor  219  is too low, the computing device  224  may display a warning signal on the display  226  or provide an audio signal through the speaker  312  so that the surgeon can check if the outflow valve  217  is closed or not. In another example, if both of the pressures  232  measured by the sensors  215  and  219  are too low, the computing device  224  may issue a visual or an audio warning signal so that the surgeon can check if the inflow tube  213  or inflow stopcock  506  is blocked. Also, the computing device  224  may use the servo mechanism  292  to move the irrigation fluid container  216  instantly upward to thereby increase the hydraulic head of the fluid in the container  216  and increase the inflow rate. Alternatively, the computing device  224  may operate the pump  293  to inject fluid into the inflow tube  213 . 
       FIG.  3    shows a schematic diagram of the computing device  224  for monitoring the status of bladder according to embodiments of the present disclosure. In embodiments, the device  224  may include: a processor  302 , such as a microprocessor, for operating the components of the device as well as components connected to the device; a probe controller  304  for controlling the robot  220  and the robot arm  222  that holds the ultrasound probe  218  and capturing ultrasound images of the bladder; an image processor  306  for processing and analyzing the electrical signals received from the ultrasound probe  218  and the endoscope camera  212  and sending the processed signals to the display  226 ; a communication unit  310  for communicating data with various external devices, such as sensors, valve, cameras, and ultrasound probe, and forwarding the communicated signals to corresponding components of the device; a signal processor  308  for processing signals from various sensors and sending the processed signals to the display  226 ; a memory  314  for storing data; a speaker  312  for displaying audio signals to the surgeon/operator of the device; one or more ports  316  for accepting various terminals, such as power cable, USB, so on; and a user interface  318  for accepting input control signals from the user of the device. In embodiments, the display  226  may be included in the device  224  and located within the operation room so that the surgeon can watch the displayed images during the surgical procedures. 
     In embodiments, the ultrasound probe  218  may generate two-dimensional ultrasound images  230 , where each image shows the sagittal view of the bladder  204  The image processor  306  may identify the morcellator tip and inner surface of the bladder in the image, and issue a warning signal when the distance between the morcellator tip and inner surface of the bladder is less than a preset safe distance. In embodiments, the warning signal may be send to the speaker  312  so that the speaker  312  may issue an audio warning signal. In embodiments, the warning signal may be sent to the display  226  so that a visual warning message may be displayed on the display screen. 
     As discussed above, three pressure sensors  215 ,  219 , and  804  may be used to measure pressures of the fluid at various locations. In embodiments, the processor  302  may analyze the measured pressures to diagnose the problem associated with the fluid flow and bladder pressure, and send warning signals to the surgeon. For instance, if the pressure measured by the outflow-side sensor  219  is too low, the processor  302  may recognize that the outflow valve  217  is erroneously open and give an audio and/or visual warning signal to the surgeon through the speaker and/or display  308 . In embodiments, one or more of the three pressure sensors  215 ,  219 , and  804 , and the device  224  may form a feedback loop to control the pressure inside the bladder  204 . 
       FIG.  4 A  shows a schematic diagram of al ultrasonic scanner  400  according to embodiments of the present disclosure.  FIG.  4 B  shows the orientations of planes along which the ultrasonic scanner (or equivalently ultrasound probe)  400  may acquire two-dimensional images of the bladder  204  according to embodiments of the present disclosure. In embodiments, the ultrasonic scanner  400  may correspond to the ultrasound probe  218  and be controlled by the robot arm  222  as shown in  FIG.  2   . In alternative embodiments, the ultrasonic scanner  400  may be a portable device that can be manually operated by a human or other suitable mechanisms. 
     In  FIG.  4 A , the plane  406   a  shows an exemplary cross section along which the ultrasonic scanner  400  generates a two-dimensional image of the bladder  204 . In embodiments, the ultrasonic scanner  400  may be rotated by the robot arm  222  along a rotational axis  404  so that two-dimensional images are generated at preset angular intervals. In  FIG.  4 B , the arrows  406   a - 406   n  represents the cross sectional planes, as seen along the axis  404 , along which the ultrasonic scanner takes two-dimensional images of the bladder. Based on the two-dimensional images generated by the ultrasonic scanner  400 , the image processor  306  may determine the volume of the bladder  204  and the determined volume may be displayed as a number  233  on the display screen  226 . 
     In embodiments, the surgeon may in advance input the information of the patient&#39;s bladder function, such as the frequency of urination, maximum voided volume or maximum cystometric capacity from voiding diary or urodynamic study, into the device  224  before the surgical procedure of the prostate. Based on the information, the device  224  may estimate the maximum volume of the patient&#39;s bladder. In embodiments, during the morcellation procedure, the processor  302  may compare the estimated volume with the volume  233  on the display, and send a warning signal if the difference between the two volumes exceeds a preset threshold. For instance, if the volume  233  in the display is too low compared to the volume that was estimated using the bladder information, the processor  302  may determine that the bladder is not full and issue a warning signal to the surgeon. Also, the process or  302  may operate the servo mechanism  292  to move the irrigation fluid container  216  in the vertical direction to thereby adjust the flow rate or may operate the pump  293  to inject the flow into the inflow tube  213 . 
       FIGS.  4 C and  4 D  show exemplary ultrasonic images generated by the scanner  400 , taken along the directions  406   a  and  406   i , respective, according to embodiments of the present disclosure. (Figure was changed) As depicted, the image in  FIG.  4 C  shows a sagittal view of the endoscope  211  while the image in  FIG.  4 D  shows the cross-sectional view of the endoscope  211 . As discussed above, in embodiments, the image processor  306  may identify the endoscope  211  and the inner surface of the bladder  204  in the ultrasound image and determine the distance between the tip of the endoscope  211  and the inner surface of the bladder wall  204 . If the distance between the tip of the endoscope  211  and the inner surface of the bladder wall  204  is less than a preset safe distance, the image processor  306  may issue a warning signal to the surgeon. 
     If the surgeon prefers an image that is taken at one (e.g.,  406   a ) of the multiple directions (or equivalently angles)  406   a - 406   n , the surgeon may instruct the device  224  to take images along the selected direction only. For instance, the surgeon may want an image that shows a sagittal view of the endoscope  211 , such as the image in  FIG.  4 C . In another example, the surgeon may prefer an angle at which the size of the bladder image is at its maximum. In embodiments, the device  224  may be configured to control the robot arm  222  so that the ultrasonic scanner  400  is fixed along the selected direction and produce images. 
     During a surgical procedure, the surgeon may change the orientation of the endoscope  211  relative to the bladder  204  while the surgeon still prefers an image that shows the side view of the endoscope  211 . In embodiments, the device  224  may identify the endoscope  211  in each of multiple images taken at different angles, select an angle that shows the best sagittal view of the endoscope  211 , and take images in the selected angle. In this manner, the device  224  may follow the endoscope as the surgeon moves the endoscope, continuously providing the preferred view of the endoscope  211  during the surgical procedure. 
     In embodiments, the image process  306  may process the ultrasound image to identify the tip portion of the endoscope sheath  209  and may trace the tip portion as the surgeon moves the endoscope sheath during the morcellation process. 
       FIG.  5    shows an enlarged view of the working element and endoscope for morcellation procedure in  FIG.  2    according to embodiments of the present disclosure.  FIG.  6    shows a perspective view of a tip portion of the working element and endoscope for morcellation procedure according to embodiments of the present disclosure.  FIG.  7    shows a cross sectional view of the tip portion of the working element and endoscope for morcellation procedure, taken along the direction  7 - 7  in  FIG.  6   , according to embodiments of the present disclosure. As depicted, the endoscope  211  may be coupled to the endoscope sheath  209  that is inserted into urethra so that the tip portion of the endoscope sheath  209  is located inside the bladder  204 . 
     In embodiments, the endoscope sheath  209  may be in the form of a slender tube through which various working elements and the telescopes  603  may be accommodated. In embodiments, a telescope  603  (corresponding to  211  in the  FIG.  2   ) may be engaged through the endoscope sheath  209  and include a lens  604  and light sources  606  disposed around the lens. During the morcellation procedure, the lens  604  may continuously transmit the image of the tip portion of the morcellator blade set  608  and the prostate around the tip, where the real-time image is sent to the device  224  through the telescope  603  and the device  224  may display the real-time image  228  on the display  226 . In embodiments, the endoscope  211  may include multiple stopcocks  504  and  506  for regulating the flow of fluid into or out of the bladder  204 . 
     In embodiments, an inflow tube  213  may provide a flow passageway from an irrigation fluid container  216  to the inflow stopcock  506 . When the surgeon opens the inflow stopcock  506 , the irrigation fluid may enter the bladder  204  through endoscope sheath  209 , as indicated by the arrows  681 . In embodiments, the space between the outer wall of the telescope  603  and the endoscope sheath  209  form an inflow passageway through which the flow enters the bladder. 
     In embodiments, the telescope  603  may have a tubular shape and collectively refer to multiple optical elements. In embodiments, the telescope  603  may include multiple tubes thereinside, where the lens  604  and light sources  606  may be located at the proximal ends of the tubes. In embodiments, the space between the tubes and the inner wall of the telescope  603  may form an outflow passageway  610  so that the bladder is in fluid communication with the outflow stop cock  504 . 
     In embodiments, during the morcellation procedure, the outflow valve  217  may remain closed and the outflow stopcock  504  may remain open. In such a case, since there is no fluid flow through outflow passageway  610 , the pressure measured by the pressure sensor  219  may be approximately the same as the pressure at the proximal end of the outflow passageway  610 . i.e., the pressure measured by the outflow-side pressure sensor  219  may be approximately the same as the pressure near the tip of the telescope  603 . Also, since the tip of the telescope  603  (or endoscope sheath  209 ) may be located inside the bladder  204 , the pressure measured by the outflow-side pressure sensor  219  may be approximately the same as the pressure inside the bladder  204 . 
     It is noted that the endoscope  211  may have different shape and design, depending on the type or phase of surgical procedures. Also, depending on the type or phase of the surgical procedure, different working element may be engaged into the endoscope. For instance, the working element for enucleation procedure (not shown in  FIG.  5   ) may be engaged into the endoscope  211 . Upon completion of the enucleation procedure, the surgeon may disengage the working element for enucleation procedure and engage the working element for morcellation procedure, as shown in  FIG.  5   . In embodiments, the knob  520  may be used to allow the inner blade  254  to engage in or disengage out the endoscope  211 . 
     As discussed above, the surgeon may manipulate the morcellator handpiece  210  to control the reciprocal, oscillating, or rotating motion of the inner blade  254 .  FIG.  8    shows a perspective view of the morcellator blade set  608  according to embodiments of the present disclosure. As depicted, the morcellator blade set  608  may include an outer blade  802  and an inner blade  806 . For the purpose of illustration, in  FIG.  8   , the inner blade  806  is shown to be dissembled from the outer blade  802 , even though the inner blade  806  is inserted into the outer blade  802  during morcellation procedure and it may reciprocate relative to the outer blade  802  along the axial direction  810 . In embodiments, other types of morcellator blade sets may be used in place of the morcellator blade set  608 . For instance, the inner blade  806  may rotate relative to the outer blade  802 . In  FIG.  2   , the inner blade  254  may correspond to the inner blade  806  in  FIG.  8   , i.e., the distal end of the inner blade  806  is located inside the bladder  204  and the proximal end of the inner blade is located near the morcellator handpiece  210 . 
       FIGS.  9 A and  9 B  shows cross sectional views of the morcellator blade set  608  according to embodiments of the present disclosure. As depicted in  FIG.  9 A , suction may be provided to the inner blade  806  so that a portion of the large piece of prostatic adenoma (or shortly piece of tissue)  910  may be engaged into the inner blade  806 . Then, as depicted in  FIG.  9 B , the inner blade  806  may slide relative to the outer blade  802 , cutting the engaged portion of the piece of tissue  910  into a small piece of tissue  914 . The small piece of morcellated adenomatous tissue  914  of the prostate may travel through the inner blade  806  to the flexible tube  250 . In embodiments, the inner blade  806  may repeat the steps described in  FIGS.  9 A and  9 B , fragmenting the remaining piece of tissue  912  into smaller pieces of tissue. In embodiments, the fluid inside the bladder  204  may sucked through the inner blade  806  to the flexible tube  250  along with the smaller morcellated pieces of tissue  914  and exit the flexible tube  250 , as indicated by the arrow  273 . 
     In embodiments, the outer blade  802  may include a distance sensor  609  that measures the distance between the end of the outer blade  802  and the inner wall  830  of the bladder  204 . In embodiments, the distance sensor  609  may send a signal toward the inner wall  830 , detect the signal  820  reflected from the inner wall  830  of the bladder, measure the time-of-flight of the signal and send the measured time-of-flight to the device  224 . Then, based on the time of flight of the signal, the signal processor  308  may determine the distance between the end of the outer blade  802  and the inner wall  830  of the bladder. In embodiments, if the distance is shorter than a preset safe distance, the signal processor  308  may send an audio warning signal through the speaker  312  and/or display a visual warning signal on the display  226 . 
     In embodiments, the distance sensor  609  may include a signal generator for generating any suitable type of signal, such as ultrasound, infra-red light, radio signal, visible light, so on. In embodiments, the distance sensor  609  may also include a signal detector for detecting the reflected signal  820 . 
     In embodiments, as discussed above, a pressure sensor  804  may be installed on the outer blade  802  and measure the pressure inside the bladder. In  FIG.  8   , the pressure sensor  804  is shown to be located on the side wall of the outer blade  802 . However, it should be apparent to those of ordinary skill in the art that the pressure sensor  804  may be located in other suitable location near the distal end of the outer blade  802 , such as a location right next to the distance sensor  609 . 
     As discussed above, in embodiments, the monitoring of the bladder may be performed to ensure that the bladder  204  remains fully distended during the morcellation procedure. Since the variation in the bladder volume is closely related to the change in the pressure of the fluid inside and outside the bladder  204 , in embodiments, the pressure of the fluid may be measured at various locations.  FIG.  10    shows a flowchart  1000  of an exemplary process for controlling the bladder pressure according to embodiments of the present invention. At step  1002 , the device  224  may receive a first signal from the inflow-side pressure sensor  215  installed in the inflow tube  213  that forms a passageway of fluid flowing into the bladder  204 . In embodiments, the inflow tube  213  may be in fluid communication with an inlet port (such as inflow stopcock  506 ) of the endoscope. In embodiments, the inflow-side pressure sensor  215  may measure the pressure of the fluid entering the bladder  204 . At step  1004 , the device  244  may also receive a second signal from the outflow-side pressure sensor  219  installed in the drain tube  221  that is in fluid communication with an outlet port (such as the outflow stopcock  504 ) of the endoscope  211 . In embodiments, the outflow valve  217  may be closed during the morcellation procedure while the drain tube  221  may remain in fluid communication with the outlet port of the endoscope  211 . As such, during the morcellation procedure, the pressure measured by the second pressure sensor  219  may indicate the pressure inside the bladder  204 . 
     At step  1006 , based on the first and second signals, the device  224  may adjust a flow rate of fluid flowing into the bladder through the inlet port of the endoscope. In embodiments, the device  224  may move the servo mechanism  292  in the vertical direction to thereby adjust the hydraulic head of the fluid in the irrigation fluid container  216 . In embodiments, the pump  293  may be operated to inject fluid into the inflow tube  213 . At step  1008 , based on the first and second signals, the device  224  may diagnose a problem in controlling the pressure inside the bladder  204 . For instance, if the pressure measured by the inflow-side sensor  215  is within an acceptable range and the pressure measured by the outflow-side sensor  219  is below an acceptable range, the device  224  may conclude that the outflow valve  217  is open. 
     At step  1010 , the device  224  may issue a warning signal associated with the diagnosed problem to the surgeon. In embodiments, the speaker  312  may provide an audio warning signal to the surgeon. In embodiments, the display  226  may provide a visual warning signal to the surgeon. Optionally, at step  1012 , the device  224  may receive a third sensor signal from the pressure sensor  804  installed in the tip portion of the morcellator device (more specifically, outer blade  802 ), where the tip portion is located inside the bladder  204 . At step  1014 , the device  224  may repeat the steps  1006 - 1010 , taking into account the third signal as well as the first and second signals. 
     As depicted in  FIGS.  2 - 10   , one or more of the pressure sensors  215 ,  219 , and  804 , distance sensor  609 , image processor  306 , and flow meter  214  may form a feedback system to control the pressure inside the bladder. Also, signals from one or more these components may be considered to diagnose the system  200 .  FIG.  11    shows a diagnosis table  1100  according to embodiments of the present invention. In the table  1100 , diagnosis results for four scenarios are considered only, even though other scenarios may occur in the system  200 . By way of example, in the third scenario, both of the inflow-side pressure sensor  215  and the outflow-side pressure sensor  219  shows low fluid pressure (for example, less than 20 cmH2O), the distance sensor  609  shows that the bladder wall is near the tip of the morcellator (for example, less than 3 cm apart), the volume of the bladder based on the ultrasound image  230  is less than 200 ml, and the flow meter  214  shows that the flow rate is normal, which indicates that the bladder is collapsed due to excessive outflow secondary to inadvertently open outflow and/or excessive suctioning-out. In this third scenario, based on one or more of the signals from these six sensors, the processor  302  may conclude that there is an excessive outflow and give a warning signal to the surgeon so that the surgeon may check both the outflow stopcock  504  and the outflow valve  217 , or so that the surgeon may wait until the bladder is completely filled again. In embodiments, for other scenarios, the computing device  224  (or, the processor  302 ) may issue a warning signal that corresponds to the diagnosis result in the bottom row of the table  1100  and/or actuate one or more components in the system  200  to resolve the issue associated with the diagnosis result. 
     It is noted that the various threshold values in  FIG.  11    may vary depending on the patient&#39;s normal bladder volume and pressure. For instance, the bladder may be considered full when the volume of the bladder is over 450 ml (instead of 500 ml) and the bladder may be considered collapsed if the bladder volume is less than 150 ml (instead of 200 ml). In another example, the pressure measured by the sensor  804  at the morcellator tip may be considered high when the measured pressure is over 55 cm H2O and the pressure may be considered low when the measured pressure is less than 15 cm H2O. 
       FIG.  12    shows exemplary plots of pressure as a function of time according to embodiments of the present disclosure. In  FIG.  12   , the plots  1202 ,  1204  and  1206  represent the pressure, Pin, measured by the inflow-side pressure sensor  215 , the pressure, Pout, measured by the outflow-side pressure sensor  219 , and the difference between Pin and Pout during operation, respectively. For the purpose of illustration, the pressures in  FIG.  12    are measured while the irrigation fluid container  216  is fixed in space, i.e., the hydraulic head of the fluid in the irrigation fluid container  216  is not controlled by the computing device  224  during operation. 
     During the steady state, A 1 , the bladder is fully distended and the pressures remain at steady levels. During the morcellation procedure B 1 , the rate of outflow exiting the bladder through the inner blade  806  of the morcellation blade set  608  may be higher than the rate of inflow entering the bladder and as such, the pressures Pin and Pout may decrease gradually. At the end of the morcellation procedure, the bladder collapses and the pressures, Pin and Pout, fall below threshold levels. Then, the surgeon may stop the morcellation procedure and wait until the bladder is fully distended again during the waiting (refilling) period C 1  and reach a steady state A 2 . At the end of the steady state A 2 , the surgeon may resume the morcellation procedure during the time period B 2 . When the bladder collapses at the end of the time period B 2 , the surgeon may wait until the bladder is fully distended again during the waiting period C 2 . As the surgeon performs the morcellation procedure, the plots of the pressure  1202 ,  1204 , and  1206  may have a repeated pattern that is similar to the pattern including the time periods A 2 , B 2  and C 2 . 
     In embodiments, during the morcellation procedure B 1  (and B 2 ), the computing device  224  may move the servo mechanism  292  in the vertical direction, to thereby adjust the hydraulic head of the fluid in the irrigation fluid container  216 . For instance, the servo mechanism  292  may be moved upward so that the flow rate into the bladder may be increased and the pressures Pin and Pout may not decrease as shown in  FIG.  12   . In such a case, the pressures Pin and Pout during the morcellation procedure may remain the same as in the steady state A 1  (and A 2 ) and the bladder remains fully distended. Also, the surgeon may not need to stop and wait until the bladder is fully distended again during the period C 1  (and C 2 ). The broken lines  1210 - 1216  represent the pressures that are measured while the servo mechanism  292  is controlled by the computing device  224  to move along the vertical direction during operation so that the rate of low into the bladder is controlled. As indicated by the broken lines  1210 - 1216 , during the morcellation procedure, the pressures Pin and Pout remain the same as in the steady state and the bladder remains distended, and as such, there is not waiting period. 
     In embodiments, if the bladder collapses and/or the pressure Pin (and/or Pout) falls below thresholds, the computing device  204  may issue a warning sign so that the surgeon may stop the morcellation procedure right away. 
     In embodiments, one or more computing system may be configured to perform one or more of the methods, functions, and/or operations presented herein. Systems that implement at least one or more of the methods, functions, and/or operations described herein may comprise an application or applications operating on at least one computing system. The computing system may comprise one or more computers and one or more databases. The computer system may be a single system, a distributed system, a cloud-based computer system, or a combination thereof. 
     It shall be noted that the present disclosure may be implemented in any instruction-execution/computing device or system capable of processing data, including, without limitation laptop computers, desktop computers, and servers. The present invention may also be implemented into other computing devices and systems. Furthermore, aspects of the present invention may be implemented in a wide variety of ways including software (including firmware), hardware, or combinations thereof. For example, the functions to practice various aspects of the present invention may be performed by components that are implemented in a wide variety of ways including discrete logic components, one or more application specific integrated circuits (ASICs), and/or program-controlled processors. It shall be noted that the manner in which these items are implemented is not critical to the present invention. 
     Having described the details of the invention, an exemplary system  1300 , which may be used to implement one or more aspects of the present invention, will now be described with reference to  FIG.  13   . The computing system  224  in  FIG.  2    may include one or more components in the system  1300 . As illustrated in  FIG.  13   , system  1300  includes a central processing unit (CPU)  1301  that provides computing resources and controls the computer. CPU  1301  may be implemented with a microprocessor or the like, and may also include a graphics processor and/or a floating point coprocessor for mathematical computations. System  1300  may also include a system memory  1302 , which may be in the form of random-access memory (RAM) and read-only memory (ROM). 
     A number of controllers and peripheral devices may also be provided, as shown in  FIG.  13   . An input controller  1303  represents an interface to various input device(s)  1304 , such as a keyboard, mouse, or stylus. There may also be a scanner controller  1305 , which communicates with a scanner  1306 . System  1300  may also include a storage controller  1307  for interfacing with one or more storage devices  1308  each of which includes a storage medium such as magnetic tape or disk, or an optical medium that might be used to record programs of instructions for operating systems, utilities and applications which may include embodiments of programs that implement various aspects of the present invention. Storage device(s)  1308  may also be used to store processed data or data to be processed in accordance with the invention. System  1300  may also include a display controller  1309  for providing an interface to a display device  1311 , which may be a cathode ray tube (CRT), a thin film transistor (TFT) display, or other type of display. System  1300  may also include a printer controller  1312  for communicating with a printer  1313 . A communications controller  1314  may interface with one or more communication devices  1315 , which enables system  1300  to connect to remote devices through any of a variety of networks including the Internet, an Ethernet cloud, an FCoE/DCB cloud, a local area network (LAN), a wide area network (WAN), a storage area network (SAN) or through any suitable electromagnetic carrier signals including infrared signals. 
     In the illustrated system, all major system components may connect to a bus  1316 , which may represent more than one physical bus. However, various system components may or may not be in physical proximity to one another. For example, input data and/or output data may be remotely transmitted from one physical location to another. In addition, programs that implement various aspects of this invention may be accessed from a remote location (e.g., a server) over a network. Such data and/or programs may be conveyed through any of a variety of machine-readable medium including, but are not limited to: magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROMs and holographic devices; magneto-optical media; and hardware devices that are specially configured to store or to store and execute program code, such as application specific integrated circuits (ASICs), programmable logic devices (PLDs), flash memory devices, and ROM and RAM devices. 
     Embodiments of the present invention may be encoded upon one or more non-transitory computer-readable media with instructions for one or more processors or processing units to cause steps to be performed. It shall be noted that the one or more non-transitory computer-readable media shall include volatile and non-volatile memory. It shall be noted that alternative implementations are possible, including a hardware implementation or a software/hardware implementation. Hardware-implemented functions may be realized using ASIC(s), programmable arrays, digital signal processing circuitry, or the like. Accordingly, the “means” terms in any claims are intended to cover both software and hardware implementations. Similarly, the term “computer-readable medium or media” as used herein includes software and/or hardware having a program of instructions embodied thereon, or a combination thereof. With these implementation alternatives in mind, it is to be understood that the figures and accompanying description provide the functional information one skilled in the art would require to write program code (i.e., software) and/or to fabricate circuits (i.e., hardware) to perform the processing required. 
     It shall be noted that embodiments of the present invention may further relate to computer products with a non-transitory, tangible computer-readable medium that have computer code thereon for performing various computer-implemented operations. The media and computer code may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind known or available to those having skill in the relevant arts. Examples of tangible computer-readable media include, but are not limited to: magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROMs and holographic devices; magneto-optical media; and hardware devices that are specially configured to store or to store and execute program code, such as application specific integrated circuits (ASICs), programmable logic devices (PLDs), flash memory devices, and ROM and RAM devices. Examples of computer code include machine code, such as produced by a compiler, and files containing higher level code that are executed by a computer using an interpreter. Embodiments of the present invention may be implemented in whole or in part as machine-executable instructions that may be in program modules that are executed by a processing device. Examples of program modules include libraries, programs, routines, objects, components, and data structures. In distributed computing environments, program modules may be physically located in settings that are local, remote, or both. 
     One skilled in the art will recognize no computing system or programming language is critical to the practice of the present invention. One skilled in the art will also recognize that a number of the elements described above may be physically and/or functionally separated into sub-modules or combined together. 
     It will be appreciated to those skilled in the art that the preceding examples and embodiment are exemplary and not limiting to the scope of the present invention. It is intended that all permutations, enhancements, equivalents, combinations, and improvements thereto that are apparent to those skilled in the art upon a reading of the specification and a study of the drawings are included within the true spirit and scope of the present invention.