Patent Publication Number: US-2023134917-A1

Title: System, apparatus, and method for suturing

Description:
RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application Ser. No. 62/986,999, filed on Mar. 9, 2020, the subject matter of which is hereby incorporated by reference in its entirety. 
    
    
     GOVERNMENT FUNDING STATEMENT 
     This invention was made with government support under R01 EB026901 awarded by the National institutes of Health. The government has certain rights in the invention. 
    
    
     BACKGROUND 
     Within the field of medicine, there is a growing trend favoring minimally invasive procedures over traditional open surgery procedures. Minimally invasive surgery can be performed through one or more small incisions and/or a natural body orifice using, for example, an endoscope or laparoscope to deliver surgical tools to a surgical site. Favorably, minimally invasive surgery can involve less patient pain, lower risk of infection, shorter hospital stays, quicker recovery time, less scarring, and reduced blood loss when compared to traditional open surgery. 
     For example, prostate cancer is the most prevalent cancer in men and is often treated via radical prostatectomy. Taking a minimally invasive surgical approach, radical prostatectomy is typically performed transabdominally utilizing an endoscopic procedure, often with the aid of a robotic surgical system, such as the da Vinci Surgical System. The radical prostatectomy requires mobilizing the prostate via dissection/retraction of surrounding anatomical support structures, nerves, and blood vessels. After prostate removal, an anastomosis is performed to re-connect the bladder to the urethra. 
     Complications including incontinence and impotence are known to occur following surgery, and have been reported to be as high as 70% for erectile dysfunction and 21% for urinary incontinence, and although outcomes of specific hospitals and specific surgeons vary widely, some level of these complications is intrinsic to the procedure as currently performed. It has been hypothesized by surgeons that the required dissection and retraction of nerves and other structures may be largely responsible for these complications, and transurethral approaches have been attempted with straight, rigid laparoscopic instruments. The main conclusion of these studies, which included a small number of clinical cases, was that more dexterous tools are needed, particularly to enhance reconstructive suturing. 
     SUMMARY 
     A system, apparatus, and method applies sutures in a minimally invasive manner using an endoscope or other similar tubular structure. To enable this minimally invasive approach, the suture is introduced through a guiding channel of the endoscope to the surgical site inside the body. In one implementation, a dissolvable/absorbable suture with an anchor, which allows for fixation on one end, is utilized. This suture can be of the barbed type, which allows the suture to hold the tissue once the suture is passed through. With this barbed suture structure, knots are not necessary, as the barbs hold the sutured tissue together. Non-barbed sutures can also be used, but require that a knot be tied in order to maintain tension. 
     According to the system, apparatus, and method, the sutures are applied using concentric tube manipulators that extend through guiding channels of the endoscope. Each concentric tube manipulator includes a concentric tube structure including two or more pre-curved tubes, made of nitinol or other materials with super elastic qualities, that are nested inside each other. The tubes can be rotated and translated independently in order to produce dexterity at the tip of the concentric tube manipulator. The rotational and translational movement of the tubes can be imparted manually, robotically, or both manually and robotically. 
     The manipulator function of the concentric tube manipulators can be implemented by providing a structure, such as a grasper or tweezer, at the distal end of the concentric tube structure. In this implementation, an actuator member, such as a wire or cable, can be fed through the inner lumen of the concentric tube structure and can selectively actuate, e.g., via tension, the manipulator in order to manipulate tissue and/or other objects at the surgical site. The manipulator function can also be implemented via the tip of the concentric tube structure itself, e.g., for probing or piercing tissue. According to this function, the manipulator can, for example, be used to apply sutures, as described herein. In this regard, a concentric tube manipulator can be configured to deliver the suture through the endoscope tube to the surgical site. 
     In one particular configuration, the system, apparatus, and method can include two concentric tube manipulators: a needle arm and a manipulator arm. The needle arm is used primarily for piercing tissue, grasping the suture, and pulling the suture through the pierced tissue to perform the suturing operation. The manipulator arm is used to perform a variety of manipulating functions—manipulating tissue, the suture, surgical tools or even manipulating the needle arm. To facilitate this function, the manipulating arm can include a manipulator, such as a grasping tool (e.g., a claw, hook, snare, etc.). 
     In one particular application, the system, apparatus, and method can be used to apply sutures from within a body lumen to suture the lumen to a connected structure. In one specific implementation, the system, apparatus, and method can be used to perform a trans-urethral radical prostatectomy and anastomotic suturing procedure. In a tissue removal phase, the radical prostatectomy is performed to remove the prostate. Once the prostate is removed, a reconstructive anastomosis of bladder to urethra is performed from inside the lumen, i.e., from inside the urethra. Advantageously, the concentric tube manipulator suturing capabilities of the system, apparatus, and method disclosed herein allows using for this trans-urethral endoscopic reconstructive anastomosis of the bladder to urethra. 
     Of course, the utility of the system, apparatus, and method disclosed herein is not limited to the aforementioned trans-urethral endoscopic reconstructive anastomosis of the bladder to urethra in radical prostatectomy procedures. It will be appreciated that the system, apparatus, and method disclosed herein will be applicable and beneficial to suturing in a wide variety of surgical procedures. 
     According to one aspect, a surgical system for suturing a first anatomical structure to a second anatomical structure of a subject includes an endoscope tube configured to be advanced through a lumen of the first anatomical structure to a surgical site near the second anatomical structure. A manipulator arm extends through the endoscope tube to the surgical site, and includes a first concentric tube manipulator with an end effector configured to grasp and manipulate a suture at the surgical site. A needle arm extends through the endoscope tube to the surgical site, and includes a second concentric tube manipulator with a needle tip configured to pierce the tissue of the first and second anatomical structures. The needle arm is configured to grasp the suture and to retract and pull the suture through the pierced tissue so that the suture extends through and forms stitching that stitches together the first and second anatomical structures. 
     According to another aspect, the manipulator arm can be configured to grasp the suture and pull on the suture to draw together portions of the first and second anatomical structures and tighten the stitching. 
     According to another aspect, the needle arm can be configured to pierce through the tissue of the first anatomical structure from within the lumen of the first anatomical structure, to exit the first anatomical structure and be positioned outside the second anatomical structure, and to pierce the second anatomical structure and enter second anatomical structure from outside the second anatomical structure. 
     According to another aspect, the needle arm can be configured to follow a pre-curved path and extend from the endoscope tube when piercing the tissue of the first and second anatomical structures, and to follow the same curved path and retract into the endoscope tube when pulling the suture through the pierced tissue. 
     According to another aspect, the manipulator arm can be configured to hold the suture after the needle arm pulls the suture through the pierced tissue while the needle arm pierces through the first and second anatomical structures at different locations, and to manipulate the suture so that the needle arm can grasp the end of the suture and pull the suture through the anatomical structures at the different locations to form another stitch that stitches together the first and second anatomical structures. 
     According to another aspect, the stitch can be configured to connect the lumen of the first anatomical structure to at least one of a lumen, opening, or ostium of the second anatomical structure. 
     According to another aspect, the first anatomical structure can be a urethra and the second anatomical structure can be a bladder, wherein the stitching connects a lumen of the urethra to an ostium of the bladder. 
     According to another aspect, the needle tip of the needle arm can include a hollow tube with a sharpened tip, and the tube can house a snare for grasping the suture. The snare can have various configurations. For example, the snare can include a lasso or grasper. 
     As another example, the snare can include aligned openings through the sidewall of the tube forming the needle tip of the needle arm. In this configuration, extension and retraction of the needle tip while an item is positioned within one of the openings causes the item to be grasped between the opening and a terminal end portion of a tube of the concentric tube manipulator into which the needle tip is retractable. 
     As another example, the needle arm can include a chamfered block that is seated in and occupies a notch formed at the needle tip of the needle arm. The block can be actuatable to extend from the notch and retract into the notch. In a retracted position, the block closes the notch and helps define the needle tip. In an extended position, the block extends forward and opens the notch. The block is retractable to clamp down on and retain an item in the notch. 
     As another example, the needle arm can include grasping jaws that form the needle tip for suturing tissue when in a closed condition. The grasping jaws can have an open condition for receiving an item therebetween and thereafter grasping the item when placed in the closed condition. 
     As another example, the grasping jaws can include a fixed upper jaw and a pivotable the lower jaw. The upper jaw can be formed by a sharpened portion of the concentric tube forming the needle tip. 
     As another example, the needle arm can include tweezers positioned in the needle tip and extendable from the needle tip. The tweezers can include tweezer arms that are biased toward an open condition. The tweezers, when extended from the needle tip, place the tweezers in the open condition. The tweezers, when retracted into the needle tip, engage the needle arm and are urged toward a closed tweezer condition. 
     As another example, the needle arm can include a grasper formed by cutting a sidewall of a distal end of a tube of the needle arm to form a pair of grasping jaws. The sidewall of the tube is also cut to form a joint that facilitates the tube to flex or bend so that the grasping jaws can pivot opened/closed. The grasping jaws are pre-configured to flex outward to an open condition under the resilience of the tube material when extended from an adjacent concentric tube of the needle arm. The grasping jaws are configured to engage the adjacent concentric tube of the needle arm and urged toward a closed condition when retracted into the adjacent concentric tube of the needle arm. 
     As another example, the needle arm can include a flap grasper formed by cutting aligned flap portions in an outermost tube of the needle arm and an inner tube of the needle arm adjacent the outermost tube. Overlying ends of the flap portions are interconnected. The flap grasper is actuatable to open and close by rotating their respective tubes relative to each other in opposite directions. 
     The end effector of the manipulator arm can have various configurations. For example, the end effector of the manipulator arm can include forceps comprising one fixed jaw and one actuatable jaw that is pivotable about an axis from an open condition to a closed condition. 
     As another example, the end effector of the manipulator arm can include forceps including comprising a pair of actuatable jaws that are pivotable about an axis from an open condition to a closed condition. 
     As another example, the end effector of the manipulator arm can include tweezer-like graspers comprising a pair of grasper arms that are biased toward an open condition. The graspers being extended from the manipulator arm can place the graspers in an open condition. The graspers when retracted into the manipulator arm can be configured to engage the manipulator and urged toward a closed condition. In one configuration, an end cap fitted onto the end of the needle arm can include a V-shaped notch for receiving the graspers and urging the graspers to the closed condition when retracted into the notch. In another configuration, the graspers can be formed from a single sheet of material that is cut to form two upper grasping arms and a single lower grasping arm. 
     Additionally, the grasping arms can be configured to define a first stage and a second stage of the graspers. The first stage can include proximally located opposed curved portions of the grasper arms. The second stage can include distally located curved portions of the grasper arms. The first stage portions can be smaller in length, curvature, and spacing than the second stage portions. 
     According to another aspect, the surgical system can also include one or more guide tubes that extend through the endoscope tube and through which the manipulator arm and needle arm extend. In one configuration, at least one guide tube can be a curved guide tube with a curved distal end that protrudes from a distal end of the endoscope tube and is curved away from a central axis of the endoscope tube. The curved guide tube can be configured to guide the needle arm to extend from the endoscope tube in a direction that is outward with respect to the central axis. 
     In one example configuration, the outward direction at which the curved guide tube guides the needle arm can be configured to direct the needle tip to pierce through the tissue of the first anatomical structure from within the lumen of the first anatomical structure to position the needle tip outside the first and second anatomical structures. The needle arm can be further configured to follow a curved path inward toward the central axis to pierce the second anatomical structure and enter second anatomical structure from outside the second anatomical structure. The needle arm can also be configured to follow the same curved path and retract into the endoscope tube when pulling the suture through the pierced tissue. 
     In another example configuration, first and second guide tubes can protrude from the distal end of the endoscope tube and can be curved away from a central axis of the endoscope tube in opposite directions. The first and second guide tubes can guide the needle arm to extend from the endoscope tube in opposite directions that are outward with respect to the central axis. The opposite directions can be selected so that the needle arm when extending in a first opposite direction is configured to stitch together corresponding first halves of the first and second anatomical structures, and the needle arm when extending in a second opposite direction is configured to stitch together corresponding second halves of the first and second anatomical structures. 
     In another example configuration, the first and second guide tubes can include an opening connecting the tubes inside the endoscope. The opening can facilitate the needle arm selectively entering the first and second guide tubes while inside the endoscope. 
     In another example configuration, the first and second guide tubes can have portions extending within the endoscope tube that follow a helical path configured to facilitate rotation of the guide tubes within the endoscope tube without affecting the positions of their respective distal ends positioned at the tip of the endoscope tube. 
     According to another aspect, the surgical system can include an adaptor configured to fit into a distal end of the endoscope tube and support the guide tubes. 
     According to another aspect, at least one of the manipulator arms and the needle arms can include distance measuring indicia on an outer surface of an innermost tube, and a longitudinal slot on an outer tube that facilitates viewing the indicia. 
     According to another aspect, the surgical system can include an endoscope of which the endoscope tube is a portion. The endoscope can also include a camera for viewing the surgical site and an illumination source for illuminating the surgical site. 
     In one example configuration, the endoscope can include an optics port that carries the camera and illumination source. The optics port can be extendable from a distal end of the endoscope to adjust the point-of-view of the camera. 
     In another example configuration, the endoscope can also include an articulated optics structure that carries the camera and illumination source. The optics structure can include one or more segments that pivot or rotate relative to the remainder of the optics structure. The optics structure can be actuatable to adjust the point-of-view of the camera. 
     According to another aspect, the surgical system can also include an endoscope of which the endoscope tube is a portion, and a robotic assembly to which the endoscope, the manipulator arm, and the needle arm are attached. The robotic assembly can be configured to control the actuation of the manipulator arm and needle arm robotically through translation and rotation of their respective concentric tubes. 
     According to another aspect, the endoscope can include one or more irrigation ports for providing irrigation fluids to the endoscope tube for delivery to the surgical site. The endoscope can also include optics including a camera for viewing the surgical site and an illumination source for illuminating the surgical site. The robotic assembly can include a linear actuator configured to extend and retract the optics relative to the endoscope in order to position the camera point-of-view distally of the endoscope. The system can also include a deformable sleeve that connects the irrigation ports to the endoscope tube and through which the optics extend. The deformable sleeve can be configured to deform through elongation and compression to facilitate extension and retraction of the optics relative to the endoscope tube while maintaining a fluid-tight connection between the irrigation ports and the endoscope tube. 
     According to another aspect, the system can also include a suture delivery device including a tube with a lumen configured to receive the suture and retain the suture for delivery endoscopically to the surgical site. The suture delivery device can be configured to receive a leading end of the suture in a delivery device lumen and to secure an anchor end of the suture to retain the suture in the lumen during delivery. 
     According to another aspect, a method for suturing a first anatomical structure to a second anatomical structure of a subject includes advancing an endoscope tube through a lumen of the first anatomical structure to a surgical site near the second anatomical structure. The method also includes extending a manipulator arm comprising a first concentric tube manipulator through the endoscope tube to the surgical site. The manipulator arm includes an end effector configured to grasp and manipulate a suture at the surgical site. The method also includes extending a needle arm comprising a second concentric tube manipulator through the endoscope tube to the surgical site. The needle arm includes a needle tip configured to pierce the tissue of the first and second anatomical structures. The needle arm is also configured to grasp the suture and to retract and pull the suture through the pierced tissue so that the suture extends through and forms stitching that stitches together the first and second anatomical structures. 
     According to one implementation, the method can include using the manipulator arm to grasp the suture and pull on the suture to draw together portions of the first and second anatomical structures and tighten the stitching. 
     According to another implementation, the method can include actuating the needle arm to pierce through the tissue of the first anatomical structure from within the lumen of the first anatomical structure. The method can also include advancing the needle arm through the first anatomical structure to exit the first anatomical structure and become positioned outside the second anatomical structure. The method can further include actuating the needle arm to pierce the second anatomical structure and enter second anatomical structure from outside the second anatomical structure. 
     According to another implementation, the method can include advancing the needle arm along a curved path from the endoscope tube when piercing the tissue of the first and second anatomical structures, and retracting the needle arm along the same curved path when pulling the suture through the pierced tissue. 
     According to another implementation, the method can include using the manipulator arm to hold the suture after the needle arm pulls the suture through the pierced tissue while the needle arm pierces through the first and second anatomical structures at different locations. The method can also include using the manipulator arm to manipulate the suture so that the needle arm can grasp the end of the suture and pull the suture through the anatomical structures at the different locations to form another stitch that stitches together the first and second anatomical structures. 
     According to another implementation, the step of forming stitching that stitches together the first and second anatomical structures can include stitching together the lumen of the first anatomical structure to at least one of a lumen, opening, or ostium of the second anatomical structure. 
     According to another implementation, the needle tip of the needle arm can include a hollow tube with a sharpened tip. The tube can house a snare for grasping the suture. 
     According to another implementation, the method can include extending the needle arm from the endoscope tube in a direction that is outward with respect to a central axis of the endoscope tube to direct the needle tip to pierce through the tissue of the first anatomical structure from within the lumen of the first anatomical structure to position the needle tip outside the first and second anatomical structures. The method can also include extending the needle arm to follow a curved path inward toward the central axis to pierce the second anatomical structure and enter second anatomical structure from outside the second anatomical structure. The method can further include retracting the needle arm along the same curved path into the endoscope tube when pulling the suture through the pierced tissue. 
     According to another aspect, a method for suturing a urethra to an ostium of a bladder of a subject includes advancing an endoscope tube through the urethra to a surgical site near the bladder ostium. The method also includes extending a manipulator arm including a first concentric tube manipulator through the endoscope tube to the surgical site. The manipulator arm includes an end effector configured to grasp and manipulate a suture at the surgical site. The method also includes extending a needle arm including a second concentric tube manipulator through the endoscope tube to the surgical site. The method also includes extending the needle arm along a predetermined curved path to pierce through the urethra from inside the urethra to outside the urethra. The method also includes extending the needle arm along the predetermined curved path to pierce the bladder ostium from outside the ostium to inside the ostium, and grasping the suture via the needle arm. The method also includes retracting the needle arm along the predetermined curved path to pull the suture through the pierced tissue of the ostium from inside the ostium to outside the ostium. The method further includes retracting the needle arm along the predetermined curved path to pull the suture through the pierced tissue of the urethra from outside the urethra to inside the urethra; so that the suture extends through and forms stitching that stitches the urethra to the bladder ostium. 
    
    
     
       DRAWINGS 
       The foregoing and other features of the present invention will become apparent to one skilled in the art to which the present invention relates upon consideration of the following description of the invention with reference to the accompanying drawings, in which: 
         FIGS.  1 A- 1 F  illustrate a portion of an apparatus performing surgical suturing procedure at a surgical site in a subject. 
         FIG.  2    illustrates an example configuration of a robotic assembly in which the apparatus can be implemented. 
         FIGS.  3 A and  3 B  illustrate an example configuration of a distal end portion of the apparatus. 
         FIGS.  4 A- 4 C  illustrate different example configurations of the distal end portion of the apparatus. 
         FIGS.  5 - 6    illustrates example guide tube configurations of the apparatus. 
         FIGS.  7 A- 7 L  illustrate example configurations of end effectors that can be implemented in the apparatus. 
         FIGS.  8 A- 8 C  illustrate an example configuration of an end effector that can be implemented in the apparatus. 
         FIG.  9    illustrates an example configuration of indicia that can be implemented in the apparatus. 
         FIG.  10    illustrates an example configuration of an endoscope that can be implemented in the apparatus. 
         FIGS.  11 A- 11 B  illustrate an example configuration of an optics port that can be implemented in the endoscope of  FIG.  10   . 
         FIG.  12    illustrates an example configuration of an articulated optics port that can be implemented in the endoscope of  FIG.  10   . 
     
    
    
     DESCRIPTION 
     A system, apparatus, and method for suturing implements concentric tube manipulators that are delivered to a surgical site and used to perform suturing techniques, as described herein. Delivery of the concentric tube manipulators can be achieved, for example, using an endoscope, laparoscope, or other similar tubular structure configured to access the surgical site percutaneously or through a natural orifice. For purposes of this disclosure, an endoscopic delivery device is described by way of example. The system, method, and apparatus described herein are not, however, limited to an endoscopic implementation. 
     Suturing Method 
     The system, apparatus, and method disclosed herein can be used to apply sutures in a variety of manners, using different types of sutures and/or different suturing techniques. The type of suture selected and the suturing techniques can depend on the particular surgery being performed, the anatomical structures involved, and the preferences of the surgeon performing the surgery. 
       FIGS.  1 A-F  illustrate an example implementation in which the system  10  includes apparatus in the form of concentric tube manipulators  12  to perform a suturing method or procedure at a surgical site  20 . The suturing method or procedure, generally stated, involves delivering the manipulators  12  through the lumen of a first anatomical structure, and using the manipulators to suture together the first anatomical structure to a second anatomical structure in order to connect the lumen of the first structure to a lumen, opening, or ostium of the second anatomical structure. 
     In this example implementation, the manipulators  12  are delivered to the surgical site  20  through a body lumen using an endoscope (not shown in  FIGS.  1 A-F ). The system  10  uses the manipulators  12  to perform an anastomosis procedure by which the tissue forming the lumen is attached to an opening or ostium of another anatomical structure. More specifically, in this example implementation, the anastomosis procedure is used to connect the urethra  22  to the bladder ostium  24  after completing a prostatectomy procedure to remove the patient&#39;s prostate. The surgical site  20  illustrated in  FIGS.  1 A-F  is at the interface of the urethra  22  and the bladder ostium  24 . Advantageously, in this example implementation, the system and apparatus allows the surgeon to perform both the prostatectomy and the anastomosis endoscopically, through the urethra, thereby eliminating the need for incisions to access the surgical site  20 . 
       FIGS.  1 A-F  illustrate an example implementation of a method by which the urethra to bladder anastomosis can be performed by using the system  10  to deliver and apply a suture  30 . The suture  30  can be any suitable suture type, such as that illustrated in  FIGS.  1 A-F . In the example implementation of  FIGS.  1 A-F , the suture  30  is a dissolvable/absorbable suture construction with a leading end  32 , retention barbs  34  spaced along its length, and a distal anchor  36 . As mentioned above, the suture and suturing technique fits the surgical application and the preferences of the surgeon. 
     The initial step of the urethra to bladder anastomosis is to deliver the endoscope to the surgical site through the lumen of the urethra  22 . The views illustrated in  FIGS.  1 A-F  are as-viewed through a camera mounted distally on the endoscope and, therefore, the endoscope is not visible in these figures. The views illustrated in  FIGS.  1 A-F  thus correspond to those that the surgeon would encounter during the procedure. 
     Referring to  FIG.  1 A , at the initial step  40  of the urethra to bladder anastomosis method, an innermost tube  14  of a concentric tube manipulator  12  fitted with a suture delivery device or tool  42  is introduced to the surgical site  20  through endoscope. The tool  42  is configured to deliver of the suture  30  to the surgical site  20 . For this purpose, the suture delivery tool  42  includes a tube  44  constructed of a biocompatible material with a notch at its tip. The suture  30  is loaded into the lumen of the tube  44  leading end first (i.e., the end opposite the anchor  36  first). With the suture  30  fully inserted into the tube  44 , the anchor  36  is placed into the notch at the tip of the tube. 
     Once positioned at the surgical site  12 , the suture  30  is removed from the tube  44 . This can be done, for example, using a concentric tube manipulator  12  fitted with a manipulating end effector (not shown at step  40 ; see, e.g., the manipulator arm  52  of steps  50 - 80 ). The manipulator  50  can be used to grasp the suture  30  and the suture delivery tool  42  can be retrieved from the endoscope. 
     Referring to  FIG.  1 B , at step  50  of the urethra to bladder anastomosis method, a pair of concentric tube manipulators  12  are delivered to the surgical site  20  through the endoscope. These include a concentric tube manipulator  12  fit with a manipulating end effector or manipulator arm  52  attached to an innermost tube  14  of the manipulator, and a concentric tube manipulator  12  with a needle end effector or needle arm  54  formed on or from the innermost tube  14  of the manipulator. In the example implementation illustrated in  FIGS.  1 A-F , the manipulator arm  52  is a grasper including articulated jaws that are actuatable to open and close to grasp tissue, the suture  30  or the needle arm  54 . The needle arm  54  has a sharp, pointed construction that is configured to pierce tissue easily. 
     The needle arm  54  includes a sharp, pointed tip  58 , which can be achieved through a chamfered cutting of the distal tip of the innermost tube  14 . This is illustrated, for example, in  FIGS.  6 ,  7 C, and  7 D . The needle arm  54  is a hollow tubular structure that carries within its lumen a suture grasping element which, in the example configuration of  FIGS.  1 A-F , comprises an actuatable lasso  56 . The lasso  56  (see,  FIGS.  1 C-E ) is actuatable to extend from the distal tip  62  of the needle arm  54  forming a loop positioned at the needle arm tip. The lasso  56  is actuatable to retract to close the loop and cinch down on any structure positioned within the loop. In this manner, the needle arm  54  can manipulate the suture  30  by grasping it with the lasso  56 . 
     At step  50  (see  FIG.  1 B ), a stitch is initiated, with the needle arm  54  piercing the proximal structure, i.e., the urethra  22 , from interior to exterior, and piercing the distal structure, i.e., the bladder ostium  24 , from exterior to interior, positioning the tip  62  inside the bladder ostium. As shown in  FIG.  1 C , at step  60 , the lasso  56  is extended from the tip  62  of the needle arm  54  and the leading end  32  is passed therethrough, for example, by using the manipulator  52  to grasp and manipulate the suture  30 . The lasso  62  is retracted into lumen of the needle arm  54  to cinch down on and grasp the leading end  32  of the suture  30 . 
     Referring to  FIG.  1 D , at step  70 , the needle arm  54  is retracted back through the bladder ostium  24  and the urethra, pulling the suture  30  through the openings or incisions pierced by the needle arm  54  in step  50  ( FIG.  1 B ). As the suture  30  is retracted, the barbs  34  pass through the pierced openings easily, but resist being pulled back through the pierced openings, due to their barbed construction. This allows the surgeon to complete the suturing procedure incrementally with the barbs  34  holding the suture  30  in place wherever the surgeon desires. In this manner, the surgeon can elect to partially tighten the suture  30  at each stitch location, and then fully tighten the suture once all stitches are completed. 
     At this point, it is important to note that the concentric tube manipulator  12  configuration of the needle arm  54  is important to the suturing/stitching functionality of the system, method, and apparatus disclosed herein. The concentric tube manipulator functionality of the needle arm  54  allows the needle arm to follow a predetermined curved path when piercing through the urethra  22  and bladder ostium  24 , and then follow that same path when retracted back through those anatomical structures and pulling the suture  30  along with it. This allows the suturing method to be performed from inside the urethra  22  and bladder ostium  24 , by producing a consistent, repeatable stitching path of the needle arm  54  from inside the urethra to the outside, across the interface of the urethra and the bladder ostium, and through the bladder ostium and back into the surgical site  20 . Repeating this motion with consistency and along the same curved path allows the suturing to take place without tearing or other tissue damage that could result if the stitching path was inconsistent. 
     Additionally and importantly, this reliable and repeatable curved path allows the needle arm to pierce the urethra  22  and bladder ostium  24  in/from a direction that is closer to radial with respect to the diameters of these lumens. As a result, when the suture  30  is tightened, the sutured structures will be pulled together in an axial direction. Advantageously, relative twisting between the anatomical structures can be avoided due to the radial piercing achieved with the curved concentric tube configuration of the needle arm  54 . 
     To help facilitate this operation, the curvature of the concentric tube manipulator  12  and the needle arm  54  are configured with a predetermined pre-curvature. Additionally, the endoscope tube from which the concentric tube manipulators  12  are deployed can also be curved or angled, e.g., via guiding channels, in order to control the initial trajectory of the manipulators. The manipulator pre-curvatures and guiding channels can be selected to support the particular surgical operation or method in which the system and apparatus are implemented. In the example implementation of  FIGS.  1 A-F , the configurations of the endoscope guide channels, the concentric tube manipulators  12 , and the needle arm  54  can be configured specifically for the illustrated urethra to bladder anastomosis method, taking into account the respective diameters of the urethra  22  and bladder ostium  24  in order to produce a stitching path that places the suture  30  at a desired location relative to those structures. Additionally, the length of the needle arm  54  can be chosen to overcome the gap between the proximal and distal tissue structures. In the example implementation of  FIGS.  1 A-F , the gap is that between the urethra  22  and the bladder ostium  24 . 
     When the needle arm  54  is retracted in step  70  of  FIG.  1 D , the leading end  32  of the suture  30  is positioned back within the lumen at the surgical site  20 . As shown at step  80  of  FIG.  1 E , the lasso  56  can be extended/opened manipulator arm  52  can be used to grasp the suture  30  to remove it therefrom. The needle arm  54  can then be actuated to pierce the urethra  22  and bladder ostium  24  at the next stitch location in the same manner described above in regard to step  50  of  FIG.  1 B . The manipulator arm  52  can be used to facilitate grasping the lead end  32  of the suture  30  with the lasso  56  so the stitch can be completed at this next stitch location, in the same manner as described in reference to  FIGS.  1 C-E . To facilitate this piercing at the next location, the entire apparatus, e.g., the endoscope can be rotated or indexed a predetermined angle to position the stitch at the next radial location, in order to take advantage of the combined functionality of the pre-curved manipulators and their respective guide channels. 
     The steps  50 ,  60 ,  70 ,  80  of  FIGS.  1 B-E  are repeated, as necessary to complete the suturing operation. As shown in  FIG.  1 F , in the example implementation, these steps are performed a total of seven times, producing seven stitches  92 . Once all the stitches are completed, the surgeon can use the manipulator arm  52  and needle arm  54  to tighten down the suture at all of the stitch locations and to trim any excess suture  30  material from the end thereof. As shown at step  90  of  FIG.  1 F , the method results in the illustrated completed urethra to bladder anastomosis. 
     Suturing Variations 
     The suture  30  and suturing technique illustrated in  FIGS.  1 A-F  is an example of one type of suture that can be utilized in the system, apparatus, and method disclosed herein. The type of suture that is utilized is not important, nor is the suturing technique that is implemented, and either or both can be varied from those disclosed in  FIGS.  1 A-F . 
     According to one variation, instead of a single suture that forms all of the stitches, an interrupted suture technique, with one independent suture per stitch, can be implemented. This would, of course, require that individual sutures would need to be delivered to the surgical site, as shown in  FIG.  1 A . Each of these individual sutures could be applied using the same technique illustrated in  FIGS.  1 B-F . 
     According to another variation, an interrupted suture technique with two or more stitches per independent suture, can be implemented. Depending on the number of the sutures, the first stitch location of each independent suture is distributed equally along the cross section of the lumen. For each suture the first stitch is performed before the second stitch for any suture is performed. For the second and further stitches, after the release of the suture inside the proximal tissue structure, it is transported to the next stitch location inside the distal tissue structure by the suture/tissue manipulation arm. The stitch locations can be located clockwise or counterclockwise relative to the previous stitch of the same suture. 
     According to another variation, instead of a barbed suture, a running suture with suture thread (e.g., Nylon, Polypropylene, Polyester, silk) can be used for the entire suturing procedure. In this variation, the suture is stitched along the entire periphery of the adjoining tissue in a continuous manner, with a single knot tying off the suture. 
     For any of the aforementioned suturing techniques, in order to properly draw together the lumens of the urethra and bladder ostium, it can be preferable to tighten each suture stitch after all stitches have been performed. This helps draw together the lumens with proper alignment. By “full tightening,” it is meant that the two lumen ends engage each other. The sutures can be tightened fully after each stitch or partially after each stitch, bringing the two lumen ends closed to each other, but not yet touch each other. 
     Concentric Tube Manipulators 
     The concentric tube manipulators  12  are small, needle-diameter, tentacle-like robots that include multiple concentric, straight or pre-curved, elastic tubes. The curvature of the tubes can be consistent or varied along their lengths, either in-plane or out-of-plane. The concentric tubes are typically made of a super-elastic metal alloy such as a nickel-titanium alloy (“nitinol”) material. The tubes can, individually or in combination, be rotated about the longitudinal axis of the manipulator and can be translated along the longitudinal axis of the manipulator. Through rotational movement, the concentric tubes can be rotated relative to each other. Through translational movement, the tubes can be retracted into one another and extended from one another in a telescoping manner. 
     As the pre-curved tubes interact with one another through relative translational and rotational movement, they cause one another to bend and twist, with the tubes collectively assuming a minimum energy conformation. The pre-curvature(s) of the tube(s) for a given concentric tube manipulator  12  can be selected to provide a desired workspace throughout which the tip can access, or to follow a desired path so as to allow for the performance for a particular function or to navigate a particular anatomical structure. The curved shape of the distal end of the manipulator  12  is controlled via translation and rotation of each tube at a proximal location (e.g., at its base) outside the patient where the tubes are connected to the transmission. Through the combined movements of the tubes, the distal tips of the manipulators  12  can be made to perform desired movements within the workspace. 
     The needle arm consists similarly to the manipulator arm of one or more pre-curved tubes made of nitinol or other materials with super elastic quality ( FIG.  8   a   ). It can expose circular or a non-circular cross section. The cross section can for example be elliptic or rectangular to prevent the spontaneous sudden rotations of the tubes due to elastic deformation energy. The non-circular cross section avoids the independent relative rotations of the tubes to each other, such that they can only be translated independently. The curvatures of the tubes can exhibit different shapes similar to the manipulator arm. The translation of the needle tubes enables establishing different overall curvatures in order to overcome various distances between the separated lumen ends. The inner lumen inside the inner most tube can be used to introduce a snare structure, such as a lasso or grasper, for grasping the suture, or an actuation member for actuating an end effector on the tube&#39;s tip. 
     The tubes of the needle arm can possess marks ( FIG.  8   b   ) on the outer surface along its length to provide visual feedback about the deployed length of the tube and therefore the location of the piercing point in the distal tissue structure. In the case of two or more tubes the outer tubes would have a cutout along their whole length to be able to see the deployed length of the inner most tube through the cut out. The lines can be etched, laser cut or similar. 
     To overcome the distance inside along the endoscope, the tubes can consist of a pre-curved super-elastic end section and a straight steel section. Steel would counter the torsional twisting more than the super-elastic material. 
     Surgical System 
     The surgical system  10  is illustrated in greater detail in  FIG.  2   . Referring to  FIG.  2   , the concentric tube manipulators  12  are delivered via an apparatus in the form of a robotic assembly  100  supported on a support structure  106 . The robotic assembly  100  can, for example, be similar or identical in form and/or function to the robotic assembly disclosed in U.S. Pat. No. 10,238,457 B2, which was issued on Mar. 26, 2019 to Herrell et al. The disclosure of U.S. Pat. No. 10,238,457 B2 is hereby incorporated by reference in its entirety. 
     The robotic assembly  100  includes the concentric tube manipulators  12 , a transmission for imparting translational and rotational movements to the concentric tube manipulators, and a motor pack including electric motors for supplying power for operating the transmission. The transmission and motor pack are not illustrated in great detail and are identified generally at  102  in  FIG.  2   . 
     The robotic assembly  100  can be controlled locally via control handles  104  mounted to the rear of the assembly. Alternatively, the robotic assembly  100  can be controlled remotely from a surgeon&#39;s console. For the former implementation, the robotic assembly  100  can include a display screen on the rear of the assembly (not shown), between the control handles  104 , that allows the surgeon to view the workspace while controlling the operation of the manipulator arm  52  and needle arm  54 . 
     The motor pack  102  of the robotic assembly  100  includes one or more controllers (not shown), such as microcomputers, that receive high level control signals from the control handles  104 . The high level control signals are indicative of desired tip movements of the concentric tube manipulators  12  inputted by the surgeon via the control handles  104 . The controllers translate the high level control inputs and provide commands to low level motor controllers in the motor pack in order to operate the motors to produce tube movements (rotation and/or translation) via the transmission that will result in the desired tip motions. 
     The robotic assembly  100  also includes an endoscope  110 , including an endoscope tube  112  through which the concentric tube manipulators  12  are deployed. The endoscope  110  can be a commercially available endoscope or it can have a custom configuration built specifically for robotic assembly  100  and/or for the particular implementation of the system  10 . For the example urethra to bladder anastomosis implementation illustrated in  FIGS.  1 A-F , the endoscope tube  112  can be a 26 Fr (8.6 mm) endoscope tube for facilitating insertion through the urethra. 
     The support structure  106  supports the robotic assembly  100  for gross movement. By “gross movement,” it is meant that the support structure supports the robotic assembly  100  for movement as a whole. The support structure  106  can, for example, support the robotic assembly  100  for translational and/or rotational movement about the axes identified at A, B, and C in  FIG.  2   . To facilitate ease in this movement, the support structure  106  can be outfitted with counter weighting, balancing, pre-loading, etc. so that the robotic assembly  100  can be moved easily by the surgeon. For the example urethra to bladder anastomosis implementation illustrated in  FIGS.  1 A-F , this gross movement can allow the surgeon to insert the endoscope tube  112  into the urethra to place its distal end  114  at the surgical site. 
     The support structure  106  can also include a locking mechanism for locking the position of the robotic assembly  100  relative to the patient once the endoscope tube  112  is inserted in the urethra with its distal end  114  positioned at the surgical site. Once locked in this position, the concentric tube manipulators  12  can be operated robotically via the control handles  104  to perform the fine movements and operations with the concentric tube manipulators  12  and the affixed tools to perform the surgical procedure. 
     Endoscope Design 
     Referring to  FIGS.  3 A-B , the endoscope  110  can be a conventional, commercially available endoscope that can be purchased “off-the-shelf,” so to speak. The endoscope  110  can, for example, be a conventional 26 Fr (approx. 8.6 mm) endoscope with optics and illumination included. In this configuration, the endoscope  110  includes a camera  120  and light source  122  disposed at the distal end  114  of the endoscope tube  112 . The concentric tube manipulators  12  are deployed through an inner lumen  124  of the endoscope tube  112 . For this purpose, the endoscope  110  can be fitted with guide tubes that create channels through which the concentric tube manipulators  12  can be deployed. 
     The example endoscope  110  configuration illustrated in  FIGS.  3 A-B  includes three guide tubes for guiding the concentric tube manipulators  12  through the endoscope tube  112 . A straight guide tube  130  is located centrally in the endoscope tube  112 , and two curved guide tubes  132  located below the straight guide tube. The straight guide tube  130  is aimed axially from the distal end  114  of the endoscope tube. The curved guide tubes  132  follow a curved path, exiting the distal end  114  in an outward direction aimed away from each other and from the centrally located straight guide tube  130 . 
     The guide tubes  130 ,  132  illustrated in  FIGS.  3 A-B  have a circular cross-section. The guide tubes could, however, have alternative non-circular cross-sections, such as elliptical or rectangular. Such non-circular cross sections could help avoid instabilities between the multiple tubes forming the concentric tube manipulators  12 , and between the manipulators and the guiding channels themselves. This could be beneficial in offering a degree of safety, given that these instabilities can result in unwanted tube movements. 
     The guide tubes  130 ,  132  can be placed inside the inner lumen  124  of the endoscope  110  sliding them in longitudinally. The guide tubes  130 ,  132  can be replaced easily and do not influence the functionality of the endoscope  110 . The guide tubes  130 ,  132  are secured via an adapter  134 , constructed of metal or plastic, that is fixed in the endoscope lumen  124  at the distal end  114  of the endoscope tube  112 . The adapter  134  can be secured to the endoscope tube  112  in any suitable manner, such as an interference fit, gluing, or other means. An adapter (not shown) similar to the adapter  134  can be installed at the proximal end of the endoscope  110  at or near the interface with the robotic assembly  100 . This adapter can support the guide tubes  130 ,  132  at the proximal end and can facilitate installation and removal of the guide tubes, as well as secure the tubes in the installed condition, e.g., via latching mechanism. 
     The adaptor  134  is configured to fill the open space in the tube  112  left by the camera  120  and light sources  122 . The adaptor  124  includes openings through which the guide tubes  130 ,  132  extend, and supports the tubes at the distal end  114  where they exit the endoscope  110 . As can be seen in  FIG.  3 B , the adaptor  134  can be configured to occupy a small portion of the length of the endoscope tube  112  at the distal end  114 . The adaptor at the proximal end of the endoscope  110  can be similarly configured. 
     As shown in  FIG.  3 A , the adaptor  124  can permit the guide tubes  130 ,  132  to extend or protrude somewhat from the distal end  114  of the endoscope tube  112 . This can be advantageous because their protrusion from the distal end  114  allows the channels and their respective concentric tube manipulators  12 , to clear the sidewall of the endoscope tube  112  when exiting the endoscope  110 . This is especially true with the curved guide tubes  132  because the concentric tube manipulators  12  exiting from these guide tubes can benefit from this clearance when exiting at an angle from the endoscope  110 . 
     The endoscope  110  is, of course, not limited to a conventional, purchased off-the-shelf design. The endoscope  110  can also be of a custom design, configured specifically to perform the functions described herein. Implementing a custom endoscope  110  can be advantageous, for example, in that the adapter  134  and guide tubes  130 ,  132  can be integral to the design, as opposed to being retrofitted into a commercial endoscope. A custom endoscope  110  configuration can also be advantageous in terms of interfacing the scope with the robotic assembly  100  and facilitating some of the system functionality associated therewith. Some of these modifications/customizations are discussed herein below (see, e.g.,  FIG.  10   ). 
     Adaptor/Guide Tube Variations 
     The configurations of the adaptor  134  and guide tubes  130 ,  132  can be selected to facilitate the particular surgical procedure being performed via the surgical system  10 . For example, the configuration illustrated in  FIGS.  3 A-B  can be particularly advantageous in performing the urethra to bladder anastomosis procedure illustrated in  FIGS.  1 A-F . Noting that the anastomosis procedure illustrated in those figures requires two concentric tube manipulators  12 , i.e., the manipulator arm  52  and the needle arm  54 , the presence of the third guide tube, particularly the presence of two curved guide tubes  132 , is advantageous, especially to the execution of an anastomosis procedure such as that illustrated in  FIGS.  1 A-F . 
     Those skilled in the art will appreciate that performing the stitches  92  about the periphery of the adjoined structures  22 ,  24  (see  FIG.  1 F ) utilizing the curved needle arm  54  approach discussed above requires a specific and/or preferred angle of attack at the location of each stitch. Because the manipulator arm  52  does not require a specific curved approach, but preferably enjoys dexterity in all directions, it can be deployed through the straight guide tube  130  and can thereby easily access the entire workspace at the surgical location  20 . 
     The needle arm  54 , however, benefits from and may even require deployment through the curved guide tube  132  in order to achieve the curved path necessary to perform the suturing function. As discussed above, the outside-in/inside-out approach for piercing the tissue with the needle arm  54  requires a precise curved path. Because the required curved path is different at the location of each stitch  92 , the desired direction at which the curved guide tube  132  directs the needle arm  54  from the endoscope  110  is different for each stitch. To achieve the proper directional alignment of the curved guide tube for each stitch location, the support structure  106  can be adjusted to rotate the entire robotic assembly  100  about the axis A (see  FIG.  2   ) in order to adjust the direction of the curved guide tube  132 . 
     Following this approach, however, the robotic assembly  100  will eventually be oriented upside down in order to achieve the required orientation of the curbed guide tube(s)  132 . This is disadvantageous because this would place the control handles  104  and the display screen upside down as well, making it difficult or impossible for the surgeon to perform the operation. One solution would be to allow the control handles to pivot or rotate 180-degrees for upside down operation. In this instance, the display screen could flip the image to right side up from the surgeon&#39;s perspective. 
     Simplifying this situation, however, is the inclusion of the second curved guide tube  132 , which points in the opposite direction. Because of this, one of the curved guide tubes  132  can be used to deliver the needle arm  54  and apply sutures on one side, e.g., to the left of the surgical site  20  as viewed in  FIGS.  1 A-F . The other of the curved guide tubes can be used to deliver the needle arm  54  and apply sutures on the other side, e.g., to the right of the surgical site  20  as viewed in  FIGS.  1 A-F . The example configuration of the endoscope  110  illustrated in  FIGS.  3 A-B , specifically the curved guide tubes  132  and adapter  134 , is particularly well-suited to perform the urethra to bladder anastomosis surgical procedure. 
     The configurations of the guide tubes  130 ,  132  and the adaptor  134  are not limited to those illustrated in  FIGS.  3 A-B . Variations of the adaptor  134  and/or guide tubes  130 ,  132  can be implemented in the surgical system  10 , depending on factors such as the surgical procedure being performed and the preferences of the surgeon. 
     Generally speaking, the system  10  implements two or more guiding channels  130 ,  132  in the endoscope  110 . This is because, for suturing procedures, at least two channels are required—one for the needle arm  54  and one for the manipulator arm  52 . Examples of these variations are illustrated in  FIGS.  4 A-C . As with the configuration of  FIGS.  3 A-B , the channels extend beyond the distal end  114  of the endoscope  110  to provide the operator with the visual feedback regarding the location of the channels and, also, the locations where the needle and manipulating arms will exit the endoscope. 
     Referring to  FIG.  4 A , a first variation of the endoscope  110  includes an adaptor  134  configured to support two straight guide tubes  130 . The straight tubes  130  in this configuration can be sized, positioned, and arranged symmetrically in the endoscope  110 . 
     Referring to  FIG.  4 B , a second variation of the endoscope  110  includes an adaptor  134  configured to support one straight guide tube  130  and one curved guide tube  132 . 
     Referring to  FIG.  4 C , a second variation of the endoscope  110  includes an adaptor  134  configured to support two curved guide tubes  132 . 
     Referring to  FIG.  5   , the guide tubes  130 ,  132  can be flexible and configured to extend along a helical path within the inner lumen  124  of the endoscope tube  112 . This arrangement can be beneficial in that the adapter  134 , or a portion thereof supporting the guide tubes  130 ,  132 , can be configured to rotate so that the guide tubes can switch sides at the tip of the endoscope  110 . Configuring the guide tubes  130 ,  132  in this helical configuration provides the excess guide tube length within the endoscope  110  necessary to support rotation via the adaptor  134  while maintaining the ends of the guide tubes positioned at the tip of the endoscope. 
     Referring to  FIG.  6   , according to one example implementation, the endoscope  110  is outfitted with guide tubes  130 ,  132  that are fused together or otherwise joined at least along a distal section of the tubes, proximal to the adapter  134  at the distal end  114  of the endoscope tube  112 . In this fused/joined configuration, the tubes  130 ,  132  share a center wall  160 . At a point proximal of the distal end  114  and adapter  143 , there is a break in the center wall  160  defining an opening  162  that allows for communication between the guide tubes  130 ,  132 . This allows the concentric tube manipulator  12 , particularly the needle arm  54 , to be swapped between the guide tubes  130 ,  132 . 
     The swapping of guide tubes  130 ,  132  with the needle arm  54  relies on the curved nature of the tubes that make up the manipulator  12 . To achieve this swapping, the manipulator  12  is actuated axially and rotationally to back the manipulator out of the adapter  134  so that its tip is positioned proximally of the opening  162 . The manipulator  12  is then rotated so that its curve is directed toward the center wall  160  and opening  162 . The manipulator is then advanced axially toward the distal end  114  of the endoscope tube  112 . When the tip of the manipulator  12  reaches the opening  162  it will deflect into the opposite tube  130 ,  132  due to its tendency to conform to its pre-curved configuration. To promote this transfer between the tubes, the guide tubes can be configured to have a non-circular configuration in the area of the center wall  160  and opening  162 , so that the manipulators  12  can slide along a flat surface just prior to transferring through the opening. 
     Although  FIG.  6    shows a guiding channel of equal diameter along its whole length, it could be configured so that a portion proximal to the opening  162  has a diameter that is reduced, in order to free-up space in the endoscope  110 . In this instance, the guide tubes  130 ,  132  can be fitted with a joint or fitting that acts as a reducer for combining the guide tubes and reducing the diameter proximally of the adapter  134 . In one particular configuration, the adapter  134  can be configured to include the reducer, center wall  160 , and opening  162  and can be configured to receive the single, small diameter channel that leads to the split, at the adapter  134 , to the two separate guide tubes  130 ,  132 . 
     In this manner, two manipulators  12 , such as a manipulating arm  52  and a needle arm  54 , can be swapped between guide tubes  130 ,  132 . Advantageously, since the concentric tube manipulators  12  are operated robotically via the robotic assembly  100 , this swapping can be automated. The swapping can be initiated through a single command. 
     Although the concentric tube manipulator  12  illustrated in  FIG.  6    is a needle arm  54 , the implementation of the swapping feature is equally well-suited for use with the manipulator arm  52 . In fact, the swapping features of  FIG.  6    can be particularly advantageous in an endoscope configuration including only two guide tubes  130 ,  132 , because this allows for the manipulator arm  52  and needle arm  54  to be swapped. Of course, the swapping feature could be implemented in a configuration that includes more than two guide tubes. 
     End Effectors 
     The concentric tube manipulator  12  can be equipped with a variety of end effectors that enable grasping, manipulating, cutting, and other operations. For this purpose, the lumen of the innermost tube  14  of the manipulator  12  facilitates the passing through of an actuating member, such as a cable, wire, or rod, configured to actuate the end effector through pushing, pulling, rotation, etc. The actuating member can be actuatable robotically via the robotic assembly  100 . Examples of different end effectors that can be implemented in the system  10  at the end(s) of the concentric tube manipulator(s)  12  and actuated robotically via the robotic assembly  100  are illustrated in  FIGS.  7 A- 7 L and  8 A- 8 C . 
     As shown in  FIG.  7 A , the end effector can be forceps  170  with one fixed jaw  174  and one actuatable jaw  174  pivotable about an axis, as illustrated generally by the curved arrow in  FIG.  7 A . The actuatable jaw  174  can be actuated via an actuating member (cable, wire, rod, etc.) extending through the innermost tube  14  of the concentric tube manipulator  12  (in this instance, a manipulating arm  52 ). 
     As shown in  FIG.  7 B , the end effector can be forceps  180  with two actuatable jaws  184  pivotable about an axis, as illustrated generally by the curved arrows in  FIG.  7 B . The actuatable jaws  184  can be actuated via an actuating member (cable, wire, rod, etc.) extending through the innermost tube  14  of the concentric tube manipulator  12  (again, in this instance, a manipulating arm  52 ). 
     As shown in  FIG.  7 C , the end effector is the lasso  56  described above with reference to the method illustrated in  FIGS.  1 A-F . The lasso  56  is actuatable to extend from and retract into the inner lumen of the concentric tube manipulator  12  which, in this case, is a needle arm  54 . The extension and retraction of the lasso  56  out of and into the pointed tip  58  of the needle arm  54  is illustrated generally by the arrow in  FIG.  7 C . The lasso  56  can be actuated via an actuating member (cable, wire, rod, etc.) extending through the innermost tube  14  of the concentric tube manipulator  12 . It will therefore be appreciated that the needle arm  54  of  FIG.  7 C  can be used both for stitching tissue and for manipulating tissue, sutures, or other objects. 
     As shown in  FIG.  7 D , the end effector can be aligned openings  190  through the sidewall of the innermost tube  14  of the concentric tube manipulator  12 , which forms the needle arm  54 . As shown, the openings  190  can be located proximally from the needle tip  58  of the innermost tube  14 . The extension and retraction of the innermost tube  14  is illustrated generally by the arrow in  FIG.  7 D . The openings  190  allow for the needle arm  54  to be used in the manner of a lasso to grasp items by retracting the innermost tube  14  while the item is positioned within one or both of the openings. It will therefore be appreciated that the needle arm  54  of  FIG.  7 D  can be used both for stitching tissue and for manipulating tissue, sutures, or other objects. 
     As shown in  FIG.  7 E , the end effector can be a chamfered block  200  that is fixed at the distal end of the innermost tube  14  of the concentric tube manipulator  12 . The block  200  is seated in and occupies a notch  202  in the innermost tube  14  and helps form the needle tip  58  of the needle arm  54 . As shown, the block  200  is extendable and retractable from the notch  202 , via an actuating member  204 , such as a cable, wire, rod, etc. The extension and retraction of the innermost tube  14  is illustrated generally by the arrow in  FIG.  7 E . 
     In the retracted position, shown in solid lines, the block  200  closes the notch  202  and helps define the needle tip  58 , with its chamfered surface being co-planar with the chamfer of the innermost tube  14  at the tip. In the extended position, shown in dashed lines, the block  200  extends forward and opens the notch  202 . In this example implementation, the block  200  and the notch  202  allow for the needle arm  54  to be used in the manner of a grasper. To do so, the needle arm  54  is maneuvered, while the block  200  is extended, so that an object or tissue to be grasped is positioned in the notch  202 . The block  200  is then retracted to clamp down on and retain the object/tissue in the notch  202 . It will therefore be appreciated that the needle arm  54  of  FIG.  7 E  can be used both for stitching tissue and for manipulating tissue, sutures, or other objects. 
     The example implementation of  FIG.  7 F  combines elements of previous example implementations. As shown in  FIG.  7 F , the concentric tube manipulator  12  is a needle arm  54  in which the needle tip  58  is formed by grasping jaws  210 . In the example implementation of  FIG.  7 F , the upper jaw  212  is fixed and the lower jaw  214  is pivotable about an axis, as indicated generally by the curved arrows in the figure. The actuation can be effectuated via an actuating member, such as a cable, wire, rod, etc. The jaws  210  can be actuated to grasp and manipulate tissue or objects. Maintaining the jaws  210  in the closed condition allows the concentric tube manipulator  12  to be used to pierce and stitch tissue. It will therefore be appreciated that the concentric tube manipulator  12  of  FIG.  7 F  can be used both for stitching tissue and for manipulating tissue, sutures, or other objects. 
     The example implementation of  FIG.  7 G  is similar to the implementation of  FIG.  7 F . As shown in  FIG.  7 G , the concentric tube manipulator  12  is a needle arm  54  in which the needle tip  58  is formed by grasping jaws  220 . The upper jaw  222  is fixed and the lower jaw  224  is pivotable about an axis, as indicated generally by the curved arrows in the figure. The difference between the configuration of  FIG.  7 G  and the configuration of  FIG.  7 F  is that the fixed jaw  222  of  FIG.  7 G  is formed as a part of the innermost tube  14  itself. The actuation of the lower jaw  224  can be effectuated via an actuating member  226 , such as a cable, wire, rod, etc. The jaws  220  can be actuated to grasp and manipulate tissue or objects. Maintaining the jaws  220  in the closed condition allows the concentric tube manipulator  12  to be used to pierce and stitch tissue. It will therefore be appreciated that the concentric tube manipulator  12  of  FIG.  7 G  can be used both for stitching tissue and for manipulating tissue, sutures, or other objects. 
     As shown in  FIG.  7 H , the end effector can be tweezer-like graspers  230  in combination with an end cap  232  fitted onto the end of the innermost tube  14  of the concentric tube manipulator  12  which, in this instance is a manipulator arm  52 . The graspers  230  can be constructed from a single sheet of material, e.g., a super-elastic metal (nitinol) or other resilient metal or plastic material, that is cut to form two upper grasping arms  234  and a single lower grasping arm  236 . Since the graspers can be cut from a single sheet of material, the upper grasping arms  234  can be spaced apart from each other, and the lower grasping arm  236  can be formed from the material between the upper grasping arms. The upper and lower grasping arms  234 ,  236  can be further bent, machined, etc. to produce the generally C-shaped profile shown in  FIG.  7 H . 
     As shown in the exploded portion of  FIG.  7 H , the end cap  232  can be fitted onto the innermost tube  14  of the concentric tube manipulator  12 . The end cap can include a V-shaped notch  240  that corresponds to a V-shaped notch  242  in the distal end of the innermost tube  14 . When assembled, the notches  240 ,  242  align with each other. 
     The graspers  230  also include an actuator arm  244  that extends axially away from the grasper arms  234 ,  236  and is positioned in the tube  14  when assembled. An actuating member  246  (cable, wire, rod, etc.) extending through the innermost tube  14  of the concentric tube manipulator  12  is connected to the actuator arm  244 . The graspers  230  are actuated closed by tensioning or pulling on the actuating member  246  into the tube  14 , which causes the grasping arms  234 ,  236  to be drawn in to the notches  240 ,  242 . The grasping arms  234 ,  236  engage the notches  240 ,  242  and are urged toward each other as the grasper  230  is pulled further into the notches, which closes the grasper. Drawing the grasper  230  fully into the notches  240 ,  242  brings the grasper arms  234 ,  236  completely together, fully closing the grasper. 
     To open the grasper  230 , the actuating member  246  is released or used to push the grasper arms  234 ,  236  out of the notches  240 ,  242 . As the grasper arms  234 ,  236  leave the notches  240 ,  242 , the grasper  230  opens due to the resilient nature of the material used in its construction. 
     The end effector of  FIG.  7 I  is similar in operation to the end effector of  FIG.  7 H . In  FIG.  7 I , the concentric tube manipulator  12  is a manipulator arm  52 . The end effector is in the form of tweezer-like graspers  250  including opposed grasping arms  252  having a C-shaped configuration and presented facing concavely toward each other. The grasping arms  252  can be constructed of a material such as a super-elastic metal (nitinol) or other resilient metal or plastic material, that is cut to form the arms. The upper and lower grasping arms  252  can be further bent, machined, etc. to produce the generally C-shaped profile shown in  FIG.  7 I . The grasping arms can be secured to each other, e.g., by spot weld, an adhesive, fasteners, etc. to form the tweezer-like configuration illustrated in the figure. 
     An actuating member (cable, wire, rod, etc.) extending through the innermost tube  14  of the concentric tube manipulator  12  is connected to the graspers  250 . The graspers  250  are actuated closed by tensioning or pulling grasping arms  252  into the tube  14 . The grasping arms  252  engage the terminal end of the tube  14 , which urges the arms closer together toward each other. As the grasper  250  is pulled further into the tube, it closes further. Drawing the grasper  250  fully into the tube  14  brings the grasper arms  252  completely together, fully closing the grasper. 
     To open the grasper  250 , the actuating member is released or used to push the grasper arms  252  out of the tube  14 . As the grasper arms  252  leave the tube  14 , the grasper  250  opens due to the resilient nature of the material used in its construction. 
     The end effector of  FIG.  7 J  is identical in form and operation to the end effector of  FIG.  7 I . The only difference between the two is that the concentric tube manipulator  12  is a needle arm  54 . The end effector is tweezer-like graspers  260  including opposed grasping arms  262  having a C-shaped configuration and presented facing concavely toward each other. The graspers  260  are actuated closed by tensioning or pulling grasping arms  262  into the needle tip  58  of the needle tube  14 . Because of this, it can be important to orient the graspers  250  rotationally so that the grasping arms engage the needle tip  58  of the tube at the same time. Although the configuration of  FIG.  7 J  illustrates a two-prong grasper configuration with opposed prongs spaced 180 degrees apart, a three prong configuration, such as one in which the prongs are spaced 120 degrees apart, can also be implemented. 
     The actuating member draws the grasping arms  262  into engagement with the end of the needle tube  14 , which urges the arms closer together toward each other. As the grasper  260  is pulled further into the tube, it closes further. Drawing the grasper  260  fully into the tube  14  brings the grasper arms  262  completely together, fully closing the grasper. To open the grasper  260 , the actuating member is released or used to push the grasper arms  262  out of the tube  14 . As the grasper arms  262  leave the tube  14 , the grasper  260  opens due to the resilient nature of the material used in its construction. 
     The end effector of  FIG.  7 K  is identical to the end effector of  FIG.  7 H , except that the tweezer-like graspers  270  of  FIG.  7 K  are of a two-stage design. As shown in  FIG.  7 K , the grasping arms  272  include a first stage  274  and a second stage  276 . The first stage  274  compose a set of graspers that is smaller in length, curvature, and spacing, and is therefore suited to grasp smaller objects. The second stage  276  is larger in length, curvature, and spacing, and is therefore suited to grasp larger objects. The second stage  276  also includes the distal tips of the grasping arms  272  and can facilitate precise grasping at that location. 
     As shown in  FIG.  7 K , the end cap  278  can be fitted onto the innermost tube  14  of the concentric tube manipulator  12 . The end cap  278  is identical to that illustrated in  FIG.  7 H  and therefore includes the V-shaped notch that corresponds to a V-shaped notches in the distal end of the innermost tube  14 . When assembled, the notches align with each other. 
     An actuating member (cable, wire, rod, etc.) extending through the innermost tube  14  of the concentric tube manipulator  12  is connected to the graspers  270 . The graspers  270  are actuated closed by tensioning or pulling on the actuating member into the tube  14 , which causes the grasping arms  272  to be drawn in to the notches of the end cap  278 . The grasping arms  272  engage the notches and are urged toward each other as the grasper  270  is pulled further into the notches, which closes the grasper. Drawing the grasper  270  fully into the notches brings the grasper arms  272  completely together, fully closing the grasper. Pulled partway into the tube  14 , the grasper  270  closes the first stage  272 . Pulling the grasper  270  in further closes the second stage  274 . 
     To open the grasper  270 , the actuating member is released or used to push the grasper arms  272  out of the end cap  278 . As the grasper arms  272  leave the notches, the grasper  270  opens due to the resilient nature of the material used in its construction. 
     Advantageously, the two-stage grasper  270  can be used to grasp two objects at the same time. For example, the grasper  270  can grasp a suture in the first stage  274  and tissue in the second stage  276 . To facilitate this function, the object grasped by the first stage  274  (e.g., the suture) can be pulled into the aligned notches of the tube  14  and the end cap  278 . 
     The end effector of  FIG.  7 L  is formed entirely from the innermost tube  14  of the concentric tube manipulator  12 . As such, the tube  14  is cut at the needle tip  58  to form a pair of grasping jaws  282 ,  284 . An upper jaw  282  includes the needle tip  58 . The sidewall of the tube  14  is also cut to form a round joint  286  that facilitates the tube  14  to flex or bend so that the jaws  282 ,  284  can pivot opened/closed, as indicated generally by the curved arrows in  FIG.  7 L . The jaws  282 ,  284  can be pre-bent or otherwise pre-formed to flex outward to the illustrated open condition under the resilience of the tube material. 
     The jaws  282 ,  284  can be actuated via an actuating member (cable, wire, rod, etc.) extending through the innermost tube  14  of the concentric tube manipulator  12 . For the end effector of  FIG.  7 L , both jaws  282 ,  284  require actuation, so two actuating members can be provided. Alternatively, the actuating member can be bifurcated or split at the end so that it can be connected to each jaw  282 ,  284  individually. In either manner, tensioning the actuating member draws the jaws  282 ,  284  closed, and releasing tension on the actuating member allows the jaws to open due to their own resilience. 
     Alternatively, the jaws  282 ,  284  can be actuated by drawing or telescoping the innermost tube  14  into and out of the outer tube  16  of the concentric tube manipulator  12 , as indicated generally by the linear arrow in  FIG.  7 L . As the inner tube  14  moves out of the outer tube  16 , the jaws  282 ,  284  move to the open condition due to their pre-formed configuration. When the inner tube  14  is drawn into the outer tube  16 , the jaws  282 ,  284  engage the outer tube wall, which causes the jaws to move to the closed condition. 
     In the closed condition, the inner tube  14  can act as a needle, or the jaws  282 ,  284  can grasp and object. In this manner, the concentric tube manipulator  12  of  FIG.  7 L  can be both a manipulator arm  52  and a needle arm  54 . 
       FIGS.  8 A-C  illustrate a configuration in which the end effector is formed form sidewall portions of the concentric tube manipulator  12 . As shown in  FIGS.  8 A-C , this allows for the concentric tube manipulator  12  to be outfitted with both a needle tip and a grasper. The concentric tube manipulator  12  of  FIGS.  8 A-C  thus functions both as a needle arm  54  and a manipulator arm  52 . 
     The concentric tube manipulator  12  of  FIGS.  8 A-C  includes an end effector in the form of a flap  300  that acts as a grasper for grasping objects, such as sutures, tissue, or other surgical tools/instruments. The flap  300  is generally rectangular in form, but this is not limiting, as other shapes could be implemented. The rectangular flap  300  is formed from overlying portions of concentric tubes—the innermost tube  14  and an outer tube  16 . The overlying flap portions  302 ,  304 , respectively of the inner and outer tubes  14 ,  16 , are cut in a rectangular pattern on three sides. Free ends of the flap portions  302 ,  304  are joined together, e.g., by welding or adhesives, along a longitudinal edge  306  of the flap  300 . other shapes side flaps 
     The flap  300  is actuated through relative rotation of the inner and outer tubes  14 ,  16  from a closed condition ( FIG.  8 A ) to an open condition ( FIG.  8 B ). To actuate the flap  300  to the open condition, the inner tube  14 , the outer tube  16 , or both the inner and outer tubes are rotated about the manipulator axis so that the net effect is that the inner tube rotates clockwise as shown in  FIG.  8 C  relative to the outer tube. As a result of this relative tube rotation, the flap  300  swings to the open condition of  FIGS.  8 B-C . To actuate the flap  300  to the closed condition, the inner tube  14 , the outer tube  16 , or both the inner and outer tubes are rotated so that the net effect is that the inner tube rotates counter-clockwise relative to the outer tube. In this manner, the flap can be placed in the open condition to receive an object, and can be placed in the closed condition to grasp the object. 
     Axial Extension/Depth Measurement 
     When using the concentric tube manipulators  12  in the manner disclosed herein, it can be important to gauge or measure the axial extension of the concentric tubes  14 ,  16  relative to each other so that the degree of extension or depth can be measured or monitored. This can, for example, allow the surgeon to gauge distances and aid in depth perception at the surgical site. To facilitate this, as shown in  FIG.  9   , the concentric tube manipulator  12  can be outfitted with indicia  310  on the inner tube  14  that can be indicative of length along the tuber (e.g., cm, mm, inches, etc.). The indicia  310  can, for example, provide an indication of length from the distal end  314  of the outer tube  16  the tip  58  of the inner tube  14 . 
     To facilitate a lengthened measurement scale, the outer tube  16  can be outfitted with a slot  312  that facilitates viewing the indicia  310  positioned within the outer tube. The concentric tube manipulator  12  in  FIG.  9    is a needle arm  54 . The indicia  310  can, however, be implemented where the concentric tube manipulator  12  is a manipulator arm  52 . The inclusion of the indica  310  in the needle arm  54  implementation of the concentric tube manipulator  12  can be especially advantageous when the needle arm pierces through the urethra and can exit the field-of-view of the camera in the lumen (see,  FIG.  1 B ). The indicia  310  can allow the surgeon to gauge the position of the tip  58  of the needle arm  54  for piercing the bladder ostium back into the camera field-of-view (see also,  FIG.  1 B ). 
     The suture  30  can include indicia similar to the indicia  310  on the tube  14  of the needle arm  54 . The suture indicia can, for example, indicate a distance from the anchor  36  so that the surgeon can ascertain a location along the length of the suture relative to the anchor. For example, the indicia could include lines in patterns that become more dense as they are located in closer proximity to the anchor  36 . This suture indicia can be used to gauge the proximity of the sutured structures relative to each other in order to ascertain when the suture is sufficiently tight. This can help prevent tissue damage, since no haptic feedback is provided by the end effectors. 
     Endoscope Customization 
       FIG.  10    illustrates an endoscope  320  that includes some customization for facilitating some of the functionality described herein. The endoscope  320  can have many features and similarities to a commercial, off-the-shelf endoscope product. In fact, the endoscope  320  can begin as a commercial endoscope that is retrofitted to provide some customized functionality. The endoscope  320  includes an outer sheath or endoscope tube  322  that can carry/deliver to the surgical site a camera and optics as described above. The endoscope tube  320  can also carry/deliver to the surgical site one or more concentric tube manipulators  12  in any combination and having any configuration disclosed herein. The endoscope  320  can even carry/deliver concentric tube manipulators other than those disclosed herein or any other instrument capable of being delivered endoscopically. 
     The endoscope  320  includes irrigation channels  324  for delivering fluids to, and removing fluids from, the surgical site. For example, in the example urethra to bladder anastomosis, the bladder is filled with saline solution to open up and enable visualization of the surgical site. These irrigation channels  322  can be standard features of a commercial endoscope product. The endoscope also includes an optics port  326  through which the camera and illumination features are accessed. The irrigation channels  324  and optics port  326  are components of a rigid assembly  328  to which the endoscope tube is connected. To prevent damage/contamination of the optics, the optics port  326  is sealed from the interior of the endoscope tube  322  and the irrigation that takes place therethrough. 
     Because the concentric tube manipulators  12  implemented in the system  10  and delivered via the endoscope  320  implement a curved concentric tube configuration, maneuvering the tips of the manipulators to perform a surgical procedure necessarily involves extending, retracting, and rotating the tubes. As an inherent result of their configurations, achieving the desired tip maneuvers can necessarily involve extending the tubes a significant distance from the distal end  330  of the endoscope  320 . The optics (camera and lights), however, remain fixed in their position at the distal end  330  of the endoscope  320 . As a result, viewing the surgical site can be difficult due to the distance between the manipulator tips and the distal end  330  of the endoscope  320 . 
     Advantageously, the endoscope  320  of  FIG.  10    is configured to facilitate extending the optics from the distal end  330  in order to position the optics closer to the surgical site. At the same time, the concentric tube manipulators  12  are allowed to exit the endoscope  320  at the distal end  330  so that they can be telescoped and rotated in order to produce the tip movements necessary to perform the surgical procedure. Doing so, however, requires that the endoscope tube  322  remains stationary while the optics telescope from the endoscope tube. 
     To produce the relative movement between the optics and the endoscope tube  322 , the endoscope tube is de-coupled from the irrigation ports  324  and optics port  326 . The irrigation and optics ports  324 ,  326  are mounted on a linear actuator  334 . The actuator  334  is configured to robotically translate irrigation ports  324  and optics ports  326  axially relative to the endoscope tube  322  and the items therein, such as the guide channels and the concentric tube manipulators. This configuration allows the optics to extend from the distal end  330  of the endoscope tube  322 , and to retract into the endoscope tube  322 . 
     Translating the irrigation and optics ports  324 ,  326  relative to the endoscope tube  322  in this manner while the other structures inside the tube remain fixed is facilitated by a deformable cylindrical sleeve  332  that connects the irrigation ports  324  to the endoscope tube  322  and through which the optics port  326  extends. The sleeve  332  is constructed of an elastic material, such as a rubber or polymer material, that can be stretched and compressed. With one end connected to the endoscope tube  322  and the other end connected to the assembly  328 , the sleeve  332  provides an inner lumen that facilitates irrigation via the irrigation ports  324  and the passing through of the optics port  326 . As the ports  324 ,  326  are telescoped in and out by the actuator  334 , the sleeve  332  can stretch and compress in order to maintain the connection in a leak-proof manner. 
     Articulated Optics 
       FIGS.  11 A-B  illustrate a first configuration of articulated optics that can be facilitated by the actuatable endoscope configuration illustrated in  FIG.  10    and described in reference thereto. As shown, the optics port  326  can retract flush with the distal end  330  of the endoscope tube  322  (see,  FIG.  11 A ) and can extend distally from the distal end of the endoscope tube (see,  FIG.  11 B ). In this configuration, the curved guide channels  340  can remain positioned stationary at or near the distal end  330 , while the manipulator guide channel  342  can telescope with the optics  326 . Alternatively all of the guide channels can remain stationary. 
       FIG.  12    illustrates an alternative to the conventional endoscope optics  326  implemented in the configuration of  FIGS.  11 A-B . In  FIG.  12   , an articulated optics structure  350  carries at its tip a chip camera  352  and illumination sources  354 . The articulated optics structure  350  includes segments  360  that are connected to each other via joints that allow for pivoting movement of the segments relative to each other. The relative positions of the segments can be actuated via one or more actuator members (e.g., wire, cable, etc.) that can push/pull to pivot the segments about the joints that connect them. The optics structure  350  can enable steering the view in left-right and/or up-down directions in order to enhance visualization at the surgical site.