Total Mesorectal Resection Surgery Simulator

Abstract

To provide a TME surgical simulator.SOLUTION: A TME surgical simulator provided herein comprises a simulated tissue layers and simulated vasculature and / or organ structures. The simulated tissue surgical simulator is adapted for but not limited to laparoscopic and / or transanal TME surgical procedures.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 62 / 607,476, filed December 19, 2017, the entire disclosure of which is hereby incorporated by reference as if fully set forth herein.

[0002] This application relates generally to surgical training systems and methods, and more particularly to simulated tissue structures and models for teaching, practicing, and evaluating various surgical techniques and procedures related to, but not limited to, total mesorectal excision procedures and techniques. [Background technology]

[0003] Medical students learning new surgical techniques, as well as experienced physicians, must undergo extensive training before they are certified to perform surgery on human patients. Training must teach proper technique using a variety of medical devices to cut, penetrate, crimp, grasp, staple, cauterize, and suture various tissue types. The range of possibilities trainees may encounter is wide. For example, different organ and patient anatomies and diseases are presented. The thickness and stiffness of various tissue layers will also vary from body region to body and from patient to patient. Different procedures require different skills. Furthermore, trainees must practice their techniques in a variety of anatomical environments influenced by factors such as the patient's size and condition, the adjacent anatomical landscape, and the type of target tissue and whether it is easily accessible or relatively inaccessible.

[0004] A variety of instructional materials, trainers, simulators, and model organs are available for one or more aspects of surgical training. However, there is a need for models or simulated tissue elements that are likely to be encountered and can be used to practice endoscopic and laparoscopic minimally invasive transluminal surgical procedures. In laparoscopic surgery, a trocar or cannula is inserted to access a body cavity and create a channel for the insertion of a camera, such as a laparoscope. The camera provides a live video feed capturing images that are subsequently displayed to the surgeon on one or more monitors. At least one additional small incision is made, through which another trocar / cannula is inserted, creating a passageway through which surgical instruments can be passed to perform the procedure, which is observed on the monitor. A target tissue location, such as the abdomen, is typically enlarged by delivering carbon dioxide gas to insufflate the body cavity and create a working space large enough to accommodate the endoscope and instruments used by the surgeon. Insufflation pressure within the tissue cavity is maintained through the use of specialized trocars. Although laparoscopic surgery offers several advantages over open procedures, it requires a high skill level because the target tissue is not directly observed by the clinician. The target tissue is viewed on a monitor that displays a portion of the surgical site accessed through a small opening. Thus, the clinician must practice visual determination of tissue planes, three-dimensional depth perception on a two-dimensional display screen, instrument handing, suturing, precise cutting, and tissue and instrument manipulation. Summary of the Invention [Problem to be solved by the invention]

[0005] One procedure is total mesorectal excision (TME) for the treatment of late-stage colorectal cancer, in which the entire mesorectal covering and a portion of the rectum are removed. This procedure has shown low local recurrence rates and improved oncologic outcomes for patients. TME procedures can be performed using a combination of minimally invasive techniques, including laparoscopic and transanal approaches. Currently, there is an unmet need for educational tools for surgeons to utilize while developing and practicing the skills associated with TME procedures. [Means for solving the problem]

[0006] In accordance with various embodiments of the present invention, a TME surgical simulator is provided. The surgical simulator includes a frame having a proximal opening and a distal opening, and a simulated tissue layer connected to and covering the proximal opening. In various embodiments, the surgical simulator further includes a simulated organ assembly extending through the distal opening.

[0007] In various embodiments, the surgical simulator includes a frame having a proximal portion defining a simulated abdominal cavity and a distal portion defining a simulated pelvic cavity, and a simulated parietal peritoneum layer connected to the proximal portion, hi various embodiments, the surgical simulator further includes a simulated aorta disposed within the simulated abdominal cavity and a simulated prostate disposed within the simulated pelvic cavity.

[0008] In various embodiments, the surgical simulator includes a simulated parietal peritoneal layer and simulated mesorectal and mesenteric layers connected to the simulated parietal peritoneal layer to form a shell therebetween, hi various embodiments, the surgical simulator further includes a simulated fat filler disposed within the shell.

[0009] In various embodiments, the surgical simulator includes a frame having a proximal portion defining a simulated abdominal cavity and a distal portion defining a simulated pelvic cavity, a simulated endopelvic fascia layer disposed within the simulated pelvic cavity, and a simulated pelvic floor layer attached to the simulated endopelvic fascia layer and the distal portion of the frame. In various embodiments, the surgical simulator further includes a simulated mesorectal layer attached to the simulated endopelvic fascia layer, the simulated mesorectal layer and the simulated endopelvic fascia layer defining a simulated dissection plane therebetween.

[0010] In various embodiments, the surgical simulator includes a frame having a proximal portion defining a simulated abdominal cavity and a distal portion defining a simulated pelvic cavity, a simulated visceral peritoneum layer disposed within the simulated abdominal cavity, and a simulated peritoneum or parietal peritoneum attached to the simulated visceral peritoneum layer and the proximal portion of the frame. In various embodiments, the surgical simulator further includes a simulated mesentery layer attached to the simulated tort / endopelvic fascia layer, the simulated mesentery layer and the simulated tort / endopelvic fascia layer defining a simulated dissection plane therebetween.

[0011] Many of the attendant features of this invention will be more readily appreciated as the same becomes better understood by reference to the foregoing and following description and consideration in conjunction with the accompanying drawings.

[0012] The present invention can be understood by reference to the following description taken in conjunction with the accompanying drawings, in which reference numerals designate like parts throughout the drawings. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a perspective view of a surgical simulator or model according to various embodiments of the present invention; [Figure 2] FIG. 1 is a side view of a surgical simulator according to various embodiments of the present invention. [Figure 3] FIG. 1 is a top view of a surgical simulator according to various embodiments of the present invention. [Figure 4A] 2 is a semi-schematic front cross-sectional view taken along line AA of a surgical simulator according to various embodiments of the present invention. FIG. [Figure 4B]2 is a semi-schematic front cross-sectional view taken along line AA of a surgical simulator according to various embodiments of the present invention. FIG. [Figure 5A] 1A-1C are perspective views of portions of a surgical simulator according to various embodiments of the present invention. [Figure 5B] FIG. 1 is an exploded view of portions of a surgical simulator according to various embodiments of the present invention. [Figure 6] 1A-1C are perspective views of portions of a surgical simulator according to various embodiments of the present invention. [Figure 7] FIG. 1 is a side view of a surgical simulator according to various embodiments of the present invention. [Figure 8A] 1 is a semi-schematic front cross-sectional view taken along line BB of a surgical simulator according to various embodiments of the present invention. FIG. [Figure 8B] 1 is a semi-schematic front cross-sectional view taken along line BB of a surgical simulator according to various embodiments of the present invention. FIG. [Figure 9] FIG. 1 is a top view of a surgical simulator according to various embodiments of the present invention. [Figure 10A] 1 is a semi-schematic side cross-sectional view taken along curve CC of a surgical simulator according to various embodiments of the present invention. [Figure 10B] 1 is a semi-schematic side cross-sectional view taken along curve CC of a surgical simulator according to various embodiments of the present invention. [Figure 11A] 1A-1D are front cross-sectional semi-schematic views of various configurations of a surgical simulator according to various embodiments of the present invention. [Figure 11B] 1A-1D are front cross-sectional semi-schematic views of various configurations of a surgical simulator according to various embodiments of the present invention. [Figure 12A] 1A-1D are front cross-sectional semi-schematic views of various configurations of a surgical simulator according to various embodiments of the present invention. [Figure 12B] 1A-1D are front cross-sectional semi-schematic views of various configurations of a surgical simulator according to various embodiments of the present invention. [Figure 13] 1A-1C are front cross-sectional semi-schematic views of configurations of surgical simulators according to various embodiments of the present invention. [Figure 14]1 is a perspective view of a frame of a surgical simulator according to various embodiments of the present invention. [Figure 15] FIG. 1 is a front view of a frame of a surgical simulator according to various embodiments of the present invention. [Figure 16] 1 is a perspective cross-sectional view of a frame of a surgical simulator according to various embodiments of the present invention. [Figure 17] FIG. 1 is a top view of a frame of a surgical simulator according to various embodiments of the present invention. [Figure 18] 1 is a perspective view of a frame of a surgical simulator according to various embodiments of the present invention. [Figure 19] 1 is a perspective cross-sectional view of a frame of a surgical simulator according to various embodiments of the present invention. [Figure 20] FIG. 1 is a side view of a frame of a surgical simulator according to various embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] Generally, TME surgical simulators or models are provided to aid in surgical skill training and simulation. TME simulators include various simulated organ and / or tissue structure assemblies attached to one another and positioned within a rigid frame. The simulated organ structure assemblies provide different simulated tissue planes, particularly distinct simulated dissection planes. Various features of the assemblies further provide additional tactile and / or visual feedback along with difficulty and challenge to further aid in the training and evaluation of simulated TME surgical procedures. For example, varying sizes and / or attachments of various simulated organ structures and / or varying compositions and / or toughness of such structures and assemblies may be provided.

[0015] During a TME procedure, the fatty mesorectal envelope surrounding the rectum is removed along with a portion of the rectum. This procedure requires ligation of the associated blood supply and circumferential mobilization of the rectum and mesorectum from the pelvic cavity and surrounding structures. Once the mesorectal sample is removed, the mesorectum is inspected and scored, ranging from incomplete to complete dissection of the tissue. This is determined by the visibility of the rectal lumen where the mesorectal segment was incorrectly dissected. The scoring of the excised sample can be used to assess surgical performance as well as the risk of local recurrence.

[0016] TME procedures, therefore, require a high level of skill and understanding of pelvic anatomy. In various embodiments, a TME surgical simulator can fulfill a clinical need to mimic portions of pelvic anatomy, thus providing a learning tool for surgeons to use during their training. The TME surgical simulator, according to various embodiments, allows simulated TME procedures to be accomplished and / or completed via a laparoscopic and / or transanal approach. To accommodate compatibility with both approaches and realistically identify appropriate anatomical landmarks, the TME surgical simulator, according to various embodiments, includes at least one or more of simulated organ structures, tissues, vascular structures, and / or materials, such as the colon, mesentery, mesorectum, Tord's fascia, visceral peritoneum (retroperitoneum), endopelvic fascia, prostate, ureters, gonadal vessels, seminal vesicles, muscle layer, pelvic floor, IMA, IMV, and aorta. In various embodiments, the simulated material, simulated tissue layers, and / or simulated organ structures are also constructed to allow an end user, e.g., a surgeon, to perform a simulated procedure and provide realistic tactile feedback following the procedure similar to that encountered during a non-simulated procedure. This allows users to, among other things, practice skill development related to identifying appropriate anatomical structures and tissue manipulation. According to various embodiments, the simulated material can be confined within a simulated pelvis, which provides realistic constraints of the pelvic workspace, including, for example, the limited visualization that occurs during dissection along the curved pelvic floor during a TME procedure. In various embodiments, the simulated material allows for the extraction of a simulated mesorectal sample, which can be scored after extraction, for example, on a scale of 1 to 3 ranging from incomplete to complete dissection.

[0017] A TME surgical simulator according to various embodiments of the present invention is used to simulate a total mesorectal excision procedure. To provide a realistic training environment, the TME surgical simulator or model provides laparoscopic and transanal access for the simulated surgical procedure. The surgical simulator provides simulated materials to represent various anatomical landmarks and planes, as well as materials to simulate incisions, thereby providing significant visual and tactile feedback advantageous for understanding the handling of anatomy and tissue to better understand complications that may be encountered during the surgical procedure. Additionally, the TME surgical simulator provides materials to simulate the mesorectum, thereby allowing for mobilization, extraction, and scoring of the mesorectum. Parts of the simulator, such as the mesorectum, are designed to be sufficiently fragile and therefore capable of being damaged during the simulated procedure. This, in turn, allows for the simulated mesorectum, etc., to be evaluated and / or scored as well as the surgical procedure. In various embodiments, confinement of parts of the surgical simulator within a simulated pelvis presents a realistic challenge of working within a confined space. Additionally, in various embodiments, the simulated pelvis has curves integrated into its shape to simulate the curvature of the sacrum, which presents visualization challenges during surgical procedures. The TME surgical simulator, in various embodiments, can be used in a laparoscopic trainer with laparoscopic instruments for simulated procedures. According to various embodiments, the TME surgical simulator includes relevant and realistic anatomical structures for performance of each surgical phase of a TME procedure.

[0018] 1-3 and 14-20, the TME surgery simulator 10 includes a simulated pelvic frame or base 20. The frame 20, in various embodiments, is the stiffest or most rigid portion of the simulator 10. The frame forms a platform for elevating and / or suspending a simulated organ or tissue structure 100 secured thereto. The frame has a proximal end and a distal end, with the proximal end having a larger opening 21 compared to a constricted opening 22 at the distal end. In various embodiments, the frame is sized and shaped to fit within the confines of a laparoscopic trainer that has only specific, limited access points or channels for accessing the TME surgery simulator, and / or is not airtight or capable of sealing off insufflation gas.

[0019] The proximal portion of simulator 10 is a simulated abdominal cavity or portion thereof, and the distal portion of simulator 10 is a simulated pelvic cavity or portion thereof. Thus, the proximal portion of the frame is higher or positioned above the distal portion of the frame. Similarly, the simulated organ and / or tissue structures in the proximal portion are different from those in the distal portion of simulator 10. However, some common organ and / or tissue structures extend from the proximal portion to the distal portion. In the illustrated embodiment, supports or legs 23 extend from or near the proximal end of the frame, and supports or legs 24 extend from or near the distal end of the frame. Legs 23 extend from a proximal portion of frame floor 25, and legs 24 extend from a distal portion of frame floor 25, with the proximal portion of the frame floor being positioned higher or positioned above the distal portion of the frame. Frame floor 25 extends into sidewalls 26 and, at the distal portion, extends to a ceiling or top 27. Thus, in various embodiments, the distal portion of the frame provides a confined curved cavity or enclosure, providing a generally circular opening at the distal end, while the proximal portion of the frame provides a larger curved cavity with a larger opening. In various embodiments, the frame floor 25 begins at the proximal end of the frame and extends laterally, curving downward and folding back at the distal end of the frame. In the illustrated embodiment, the legs and frame floor are integrated or formed as a single monolithic structure, while in various embodiments, they are separate components connected to each other to form a simulated workspace for the simulator 10. In various embodiments, the frame is formed of plastic or a similar rigid material, and in various other embodiments, it comprises plastic sheets cut to shape to form the frame and attached together using, for example, mechanical fasteners. Various simulated organ and tissue structures, assemblies, or subassemblies are secured and / or supported by the frame.

[0020] 4A-10B, simulator 10 includes a simulated pelvic floor assembly, a simulated torso / endopelvic fascia assembly, a colon / rectum assembly, and a mesentery / mesorectum assembly. The simulated pelvic floor assembly includes a simulated gonadal vessel 32, a simulated aorta 33, and a simulated nerve 34, with a layer of fibrous material attached or otherwise disposed or intermixed with a simulated substance, such as padding, between the fibrous material and the simulated pelvic floor 31. In various embodiments, the simulated pelvic floor 31, simulated gonadal vessel 32, simulated aorta 33, and simulated nerve 34 are all made of silicone but are color-coordinated or otherwise visually and / or tactilely distinct from one another. Similarly, the simulated vascular structures have different thicknesses or lengths to further distinguish these structures, e.g., the simulated aorta 33 is thicker than the simulated nerves 34 and the simulated gonadal vessels 32, and / or the simulated gonadal vessels are longer than the simulated nerves 34.

[0021] According to various embodiments, the simulated Tolt fascia assembly or endopelvic fascia assembly includes a simulated Tolt fascia / visceral peritoneum / endopelvic fascia sheet or layer 41 ("Tolt / endopelvic fascia") and a simulated ureter 42, and in various embodiments, a simulated blood vessel is attached to the simulated ureter. The simulated Tolt / endopelvic fascia sheet, in various embodiments, is fabricated from silicone and a fibrous material, e.g., batting, that is attached or cured to the sheet. The simulated ureter and associated blood vessels are also made of silicone and attached to the simulated Tolt / endopelvic fascia sheet, and in various embodiments, are glued or attached to the proximal portion of the sheet and / or the smooth or non-fibrous side of the sheet. In various embodiments, the simulated ureter, simulated blood vessel, and simulated Tolt / endopelvic fascia sheet are colored or otherwise visually distinct from one another, e.g., colored and / or tactile, e.g., having different sizes, thicknesses, and / or lengths.

[0022] In the illustrated embodiment, the simulated gonadal vessels 32, simulated aorta 33, and simulated nerves 34 are glued to the simulated pelvic floor 31, which is attached to a frame, and the distal portion of the simulated pelvic floor, remote from the simulated aorta 33, is cut, folded, and shaped to also be attached to the frame. Similarly, the simulated gonadal vessels 32, simulated aorta 33, and / or simulated nerves 34 are accessible and / or visible only at or near the proximal portion of the TME surgery simulator, whereas the simulated pelvic floor extends along or through the entire length or interior of the frame. The simulated ureter 42 is also accessible and / or visible only at or near the proximal portion of the TME surgery simulator, thereby more closely simulating or closely representing portions of the abdominal cavity within the TME surgery simulator. A tort / endopelvic fascia sheet is glued or otherwise attached to the pelvic floor, disposing the simulated ureter and simulated blood vessels therebetween. Additionally, the distal portion of the tolt / endopelvic fascia sheet may be shaped, formed, and / or attached to the sheet itself to provide a generally closed or circular or oval enclosure in the distal portion of the TME surgical simulator, thereby more closely mimicking or more closely representing portions of the pelvic cavity, also within the TME surgical simulator.

[0023] According to various embodiments, the distal portion of the TME surgical simulator further includes a simulated prostate 43, a simulated bladder 44, and a simulated seminal vesicles 45, which are attached to the simulated endopelvic sheet 41. As provided in the illustrated embodiment, the simulated bladder 44 is positioned above and somewhat surrounding the simulated prostate 43, with the simulated prostate 43 having a simulated urethra 46 extending therefrom. The simulated seminal vesicles 45 are positioned adjacent to or next to the simulated prostate 43, and in various embodiments, the simulated prostate 43, the simulated bladder 44, the simulated seminal vesicles 45, and / or the simulated urethra 46 are positioned between the simulated pelvic floor 31 and the simulated endopelvic fascia sheet 41. In various embodiments, although not illustrated, the ureters are attached to the bladder toward the proximal end of the surgical simulator. In various embodiments, the simulated pelvic floor 31 covers the simulated endopelvic fascia sheet 41 and forms or defines a cavity that encases or surrounds the simulated prostate 43, simulated bladder 44, simulated seminal vesicles 45, and / or simulated urethra 46. According to various embodiments, the simulated endopelvic fascia sheet 41 is adhered to the simulated pelvic floor 31, which is then placed under outward tension or away from the interior of the frame, but still within the confines of the frame. In various embodiments, the simulated pelvic floor is stretched or pulled into the frame after being adhered to the frame, ultimately providing or assisting in providing outward tension to the simulated pelvic floor.

[0024] In various embodiments, the simulated bladder 44 is adhered to the simulated pelvic floor 31 at the pubic bone, and the simulated prostate 43 is adhered to the simulated endopelvic fascia sheet 41 anterior to the simulated rectum 53. The simulated seminal vesicles 45 are adhered only to the simulated prostate 43 and the simulated bladder 44. In various embodiments, the simulated prostate, simulated bladder, simulated seminal vesicles, simulated urethra, and / or simulated torto / endopelvic fascia sheet are colored or otherwise visually distinct from one another, e.g., colored and / or tactile, having different sizes, thicknesses, and / or lengths, for example. In various embodiments, the simulated prostate, simulated bladder, simulated seminal vesicles, and / or simulated urethra are all made of silicone.

[0025] According to various embodiments, the colon / rectum assembly includes a simulated colon 51 attached to a simulated rectum 53. The simulated colon has contours or curves, ridges, or other surface features that distinguish it from a substantially smooth, tubular simulated rectum. The transition from the ridged colon to the smooth rectum forms the rectosigmoid junction, a visual landmark during surgery, and is provided in various embodiments of the surgical simulator. In various embodiments, a simulated parietal peritoneum 54 has a proximal end or portion attached to the simulated colon 51 and a distal end or portion attached to the simulated rectum 53. The simulated parietal peritoneum 54 is further attached to a tort / endopelvic fascia sheet, positioning a mesentery / mesorectum assembly 55 therebetween.

[0026] In various embodiments, a sheet of the same material used to create the simulated tort / endopelvic fascia sheet 41 is cut and attached to itself to form the simulated mesentery 57. In various embodiments, a simulated inferior mesenteric artery (IMA) 52 is attached to the simulated colon 51, for example, at the proximal portion of the simulated colon, and is therefore only accessible / visible at the proximal portion of the TME surgery simulator.

[0027] In various embodiments, the mesentery / mesentery assembly includes a simulated mesentery 57, a simulated mesorectum 58, and a simulated IMA 52, with an inferior mesenteric vein (IMV) 56 attached to the simulated mesentery 57. The simulated mesentery is attached to or integrated into the simulated parietal peritoneum 54, and the two are joined. In various embodiments, the simulated mesentery 57 and the simulated mesorectum 58 are a single monolithic structure, with the simulated mesentery 57 located in a proximal portion of the TME surgery simulator and the simulated mesorectum 58 located in a distal portion of the TME surgery simulator. In various embodiments, the simulated IMA 52, the simulated IMV 56, and the simulated mesentery 57 are positioned in or within the proximal portion of the TME surgery simulator and, therefore, are accessible and / or visible only in the proximal portion of the TME surgery simulator. In various embodiments, the simulated IMA and / or simulated IMV are made entirely of silicone.

[0028] According to various embodiments of the present invention, the first step in a simulated TME procedure using laparoscopic techniques is entry through the simulated parietal peritoneum. The root of the mesentery is a common entry point and can be recognized by the color difference between the mesenteric fat and the posterior abdominal wall. This entry point can be recognized by observing the movement of anatomical layers as the sigmoid colon is moved with laparoscopic instruments and by identifying the distension of the inferior mesenteric artery (IMA) through the mesentery and peritoneum. Identification of anatomical features can provide a necessary starting point for the TME procedure. With reference to a TME surgical simulator, to simulate realistic tenting and dissection, the simulated parietal peritoneum 54 is adhered or otherwise attached to the simulated visceral peritoneum more rigidly than the simulated mesentery 57. The simulated colon 51, in various embodiments, is tubular and / or made of silicone. The simulated colon is adhered or otherwise attached over the simulated parietal peritoneum to simulate the descending colon. In various embodiments, the sheet thickness can be increased or decreased to vary the elasticity and structure of the simulated mesentery, and the sheet can be manufactured using a lower or higher durometer material. To allow a user to create an incision using laparoscopic energy equipment, the simulated mesentery 57, in various embodiments, is molded from a conductive material. The simulated mesentery is assembled and adhered to the simulated torso / endopelvic fascia layer 41 up to the simulated pelvic ostomy, thus allowing for differentiation of an abdominal incision from a lower pelvic incision performed via a laparoscopic approach to mobilize the rectum.

[0029] Once the simulated parietal peritoneum 54 has been penetrated, the surgeon can dissect the simulated avascular surface, e.g., the simulated tort / endopelvic fascia layer 41, to locate the simulated IMA 52, simulated IMV 56, simulated aorta 33, and / or simulated ureter 42. Identifying the ureter is important to avoid surgical complications and can further enhance the training and simulation effect. Once the simulated structures are identified, the simulated IMA 52 can be skeletonized, ligated, and separated near the simulated aorta. In various embodiments, these simulated organs and simulated vascular structures, e.g., the simulated IMA, simulated IMV, simulated aorta, and / or simulated ureter, can be cut, stapled, sutured, and knotted to simulate ligation and separation. The simulated ureter and simulated aorta allow for identification of the simulated IMA 52 and simulated IMV 56 during the simulated TME procedure. In various embodiments, the simulated vascular structures can be of varying sizes and can be hollow or hollow and fluid-filled to simulate bleeding. One or more of the simulated vascular structures can be placed within the surgical simulator without or with minimal attachment, for example, loosely glued directly to a silicone structure or otherwise attached, and / or any combination thereof. The incision is continued laterally toward the simulated abdominal wall to mobilize the simulated mesentery.

[0030] In various embodiments, the simulated avascular surface, e.g., the simulated Tolt / endopelvic fascia layer, includes a fibrous padding layer made of polyester fiberfill (polyfil). The tactile feedback of the fibers within the fibrous layer, e.g., the padding, provides sufficient resistance to allow for the use of blunt dissection with laparoscopic instruments. This dissection within the fibers allows for the skeletonization of simulated vascular structures within the layer. Below or adjacent to the simulated Tolt fascia is a thin layer relative to the simulated Tolt fascia, representing the layer penetrating the retroperitoneum or visceral peritoneum. The thinness or fragility of this layer (retroperitoneum / visceral peritoneum), and by extension, the thinness or fragility of the simulated Tolt / endopelvic fascia layer 41, simulates the increased likelihood of accidentally penetrating this plane, a challenge encountered during surgical procedures presented or simulated by the TME surgical simulator. In various embodiments, the simulated Tordt's fascia is a fibrous layer or filler, e.g., padding, that represents or simulates connective tissue and is positioned adjacent to and / or attached to a simulated retroperitoneum or simulated visceral peritoneum, e.g., one or more silicone sheets. The simulated Tordt's fascia and / or simulated retroperitoneum or simulated visceral peritoneum is positioned adjacent to and / or attached to a simulated parietal peritoneum 54.

[0031] In various embodiments, the simulated Tolt / endopelvic fascia layer 41 is a composite layer 41, e.g., comprising a fibrous material and silicone, including a simulated Tolt fascia layer together with a simulated visceral peritoneum layer or a simulated retroperitoneum layer, where the simulated endopelvic fascia layer is a continuation of the simulated Tolt fascia layer and the simulated visceral peritoneum layer or the simulated retroperitoneum layer combined together. Thus, in various embodiments, the simulated Tolt fascia layer and the simulated retroperitoneum layer or the simulated visceral peritoneum layer combine to form a composite layer, e.g., a fibrous material and silicone, and the simulated endopelvic fascia layer is a continuation of this composite layer and a continuation of the simulated Tolt fascia layer and the simulated retroperitoneum layer or the simulated visceral peritoneum layer combined together. In various embodiments, the simulated Tolt's fascia layer and the simulated visceral peritoneum or simulated retroperitoneum layer are disposed in a simulated abdominal cavity and are therefore referred to as such, whereas the simulated endopelvic fascia layer is disposed in a simulated pelvic cavity and is therefore otherwise referred to. Thus, throughout this specification, the term simulated endopelvic fascia layer can be used interchangeably with the term simulated Tolt / endopelvic fascia layer. Similarly, throughout this specification, the combined or composite layer of simulated Tolt's fascia and simulated retroperitoneum or simulated visceral peritoneum can be used interchangeably with the terms simulated endopelvic fascia layer and simulated Tolt / endopelvic fascia layer.

[0032] In various embodiments, the retroperitoneal layer or portions thereof may be yellow or otherwise distinguishable by color to further distinguish or highlight the retroperitoneal layer. Within the simulated retroperitoneal layer is an additional fiber or fibrous material, such as a padding layer (simulated Tordt's fascia), that encases the simulated aorta, nerves, and gonadal vessels. The simulated ureters and nerves are glued or otherwise attached to the simulated retroperitoneum 41, while the simulated aorta 33 and gonadal vessels 32 are glued or otherwise attached to the simulated pelvic floor. In various embodiments, the simulated pelvic floor 31 is a thin sheet molded from pink or blood / flesh-colored silicone. According to various embodiments, the simulated nerves 34, simulated ureters 42, and simulated gonadal vessels 32 are adhered or otherwise attached to the respective simulated sheets or layers at an angle or similar orientation such that pairs of simulated vascular structures are closer to each other at the proximal end of each simulated sheet or layer than at the distal end. Thus, within the simulated lower pelvic region, when the simulated ureters and simulated gonadal vessels are wrapped around the simulated mesorectum 58, the simulated vascular structures meet at the location of the simulated bladder 44 and simulated prostate 43.

[0033] To more closely simulate the appearance of the abdominal cavity beneath the simulated retroperitoneum, in various embodiments, an additional pink silicone layer comprising a simulated pelvic floor is placed beneath the simulated aorta and simulated retroperitoneal padding layer, allowing visualization of the color of the simulated abdominal cavity as it encounters the simulated retroperitoneal layer.

[0034] According to various embodiments, the silicone and fibrous layers comprising the simulated mesentery, simulated Tordt's fascia, simulated endopelvic fascia, and / or simulated retroperitoneum are bonded together using silicone. In various embodiments, silicone adhesives or other adhesives, such as cyanoacrylate adhesives and rubber cement, are used to bond the layers together. When using a silicone layer, the silicone can be easily shielded within the silicone layer, and the amount of silicone added can be easily controlled using a syringe and a sponge-like material, such as polyurethane foam. It also creates a strong silicone-to-silicone bond while also adhering to the fibrous layer, if any is present. The silicone-to-silicone bond between the silicone mesentery and the fibrous material and between the fibrous material and the silicone retroperitoneum layer allows the incision to be contained within the fibrous material, e.g., the padding layer. Similarly, in various embodiments, the silicone-to-silicone bond between the silicone retroperitoneum layer and the fibrous layer and between the fibrous layer and the red silicone layer allows the incision to be contained within the fibrous material, e.g., the padding fibrous layer.

[0035] According to various embodiments, the amount of adhesive, silicone, and / or pressure is used and varied to simulate differences in dissection of the simulated tort / endopelvic fascia layer 41. In addition, different durometers of silicone are used to vary the way two pieces made of silicone adhere to each other and tear or pull apart. This simulates different blunt dissection techniques that are advantageous for different anatomical regions. According to various embodiments, more adhesive is used in the tort / endopelvic fascia sheet 41 compared to the simulated retroperitoneal layer. Thus, tactile feedback is provided for more difficult dissections in the tort / endopelvic fascia sheet in the correct plane versus an easy, loose dissection in the wrong plane into the retroperitoneum. Since dissections within the simulated retroperitoneal layer and simulated pelvic floor 31 lead to anatomy within the simulated lower pelvis that may be damaged during the simulated surgical procedure, care must be taken to avoid surgical complications by staying within the correct dissection layers between the tort / endopelvic fascia layer 41 and the mesentery / mesorectal layers 57, 58.

[0036] According to various embodiments, the fibers or fibrous materials attached or integrated within these layers, for example, within the tort / endopelvic fascia layer 41 and / or retroperitoneal sheet, can include other low tear strength materials. These materials can be or include, but are not limited to, gel-like materials and soft conductive materials that can be used with electrosurgical energy. The use of fibrous materials, such as padding, also enhances the simulation, providing a visual appearance of the fibers observed in the simulated surgical procedure.

[0037] In various other embodiments, the fibrous or fibrous material is not contained within or otherwise integrated into the various simulated layers or sheets, and thus direct contact occurs between the sheets or layers of material within the surgical simulator. In such embodiments, the distinction between the various layers is indicated by different textures and materials as opposed to colors. However, these various embodiments, or combinations thereof, may create additional difficulty in the simulated procedures performed using the simulated TME surgical simulator due to unrealistic visual feedback.

[0038] According to various embodiments, molding or forming a fibrous material, e.g., a silicone sheet with padding, extending between or emerging from the simulated tissue layers creates a cutting plane that the user must remain within while completing the simulated incision into the simulated pelvis, as well as fully simulating the incision. This also provides an expanded and / or realistic margin for error. Furthermore, in various embodiments, the fibrous silicone composite provides similar tactile and visual feedback during the simulated procedure and can be manipulated during manufacturing to vary the level of difficulty of the simulated procedure.

[0039] According to various embodiments, the simulated dissection of the Tolt / endopelvic fascia layer 41 is continued medially and laterally toward the left wall of the frame to mobilize the simulated left descending colon and simulated sigmoid colon so that a simulated dissection can be made within the simulated lower pelvis. The descending colon and sigmoid colon are then liberated from the side wall of the frame by separating the Tolt's linea alba. According to various embodiments, a line of adhesion along the left wall resembles the linea alba created by the joining of two tissue planes.

[0040] With the simulated descending colon and simulated sigmoid colon mobilized, a posterior dissection into the simulated pelvis follows. In various embodiments, the simulated sigmoid colon passes through a silicone layer covering a frame that simulates the pubic bone in the surgical simulator. A special aspect of the TME procedure at the pelvic orifice is that the surgeon remains in the correct dissection plane between the simulated colon / mesorectum and the simulated tort / endopelvic fascia layer 41, in a region known as the plane of Holly 71, which lies between the two tissue planes. During this simulated posterior dissection, the surgeon can recognize landmarks such as the simulated nerve 34 to ensure they are following the correct dissection path.

[0041] Because the layers including the circumferential incision around the mesorectum at the posterior end and the layers including the circumferential incision around the colon are the same set of layers in the surgical simulator, the same adhesive properties are applied between these layers. Therefore, incisions through the Holley plane are more difficult or pronounced compared to incisions through the wrong plane. Furthermore, in various embodiments, the amount of fibrous material can be adjusted to make the simulated procedure more challenging. In various embodiments, the added fibrous material or padding strengthens the thin silicone sheet and facilitates fabrication when bonding the simulated layers together. The simulated tort / endopelvic fascia layer 41 continues posteriorly in the TME surgical simulator and constitutes the outer boundary of the Holley plane. The circumferential incisions around the simulated mesorectum and simulated colon are simulated by incisions of fibrous material that simulate the Holley plane. Posterior to the colon 51, in the retroperitoneal space, are a pair of thin silicone molded branching structures to simulated nerves, which serve as landmarks for the TME procedure. In various embodiments, the simulated nerve 34 is colored, for example, white, for visualization through the thin yellow silicone layer of the simulated retroperitoneum. The placement of the nerve within this simulated retroperitoneal space reflects anatomical nerve placement. Dissection within the retroperitoneal space within the surgical simulator would allow the simulated nerve 34 to be encountered in this plane, which would indicate dissection in the wrong plane.

[0042] According to various embodiments, within the TME surgical simulator, the Tolt's fascia / retroperitoneum layer and the endopelvic fascia layer are all integrated and / or the same. According to various embodiments, within the TME surgical simulator, three main simulated tissue planes or layers are provided: a simulated mesentery / mesorectum layer, a simulated Tolt's fascia / endopelvic fascia / retroperitoneum layer, and a pelvic floor / sidewall / peritoneum layer. These tissue planes should not be confused with two main dissection planes: a Holly plane 71 that occurs between the mesentery / mesorectum 57, 58 and the Tolt's fascia / visceral peritoneum / endopelvic fascia layer 41 ("Tolt / endopelvic fascia"), and a false plane 73 that occurs between the Tolt's fascia / visceral peritoneum / endopelvic fascia ("Tolt / endopelvic fascia") and the pelvic sidewall layer.

[0043] Dissecting in the wrong plane can lead to complications, such as problems associated with the anterior sacral vein or penetration of the mesorectal covering, resulting in an incomplete mesorectal dissection. By providing recognizable landmarks, such as nerves, the bladder, the prostate, and the seminal vesicles, the surgical simulator ensures or assists the surgeon or user in not dissecting in the wrong plane. According to various embodiments, in the simulated TME surgical simulator, the simulated nerve 34 is located posterior to the mesorectum and colon, and dissection in a plane that traps the nerve indicates dissection in the wrong plane. Additionally, in various embodiments, tactile feedback of loosening of the simulated layer and easier dissection therethrough is a second indicator of dissection in the wrong plane. Continuing dissection in this plane anterior to the colon toward the simulated pubis leads to the simulated structures of the prostate 43, seminal vesicles 45, and bladder 44. In various embodiments, the simulated prostate 43 and simulated seminal vesicles 45 are cast using silicone or urethane foam and colored, for example, pigment blue and pigment white, respectively, to improve simulation or to correspond to the anatomy they represent. In various embodiments, the simulated bladder 44 is made of silicone, and the simulated seminal vesicles are positioned on either side of the simulated bladder. In various embodiments, the simulated prostate includes a silicone molded simulated urethra 46 that fits beneath or extends through it. In various embodiments, these simulated structures are positioned within a frame to reflect their anatomical location for the simulation.

[0044] In various embodiments, adhesives such as silicone adhesives or cyanoacrylate adhesives can be used to adhere the simulated components to one another. Additionally, in various embodiments, gel, rubber, foam, and urethane materials can be used within the simulated components. In various embodiments, silicone, silicone foam, and urethane foam have desirable material properties for simulating the look, feel, shape, and structure of the simulated components. According to various embodiments, the simulated anatomical structure is glued onto the layer that constitutes the retroperitoneum at its posterior end during assembly and is surrounded on either side by a fibrous material, e.g., padding, that constitutes the retroperitoneal layer on its posterior end. This incorrect plane entry within the surgical simulator is believed to be the result of an incision made through the thin yellow layer that constitutes the retroperitoneum on its posterior end.

[0045] In various embodiments, special or specific adhesive or other attachment patterns are used along the simulated mesenteric and organ structures to ensure proper simulated anatomical joints are established. Variations in techniques that allow for simulated anterior dissection, according to various embodiments, include the use of silicone, foam, and / or fibrous materials to create thicker or thinner dissection planes to reduce and / or increase the level of difficulty of the simulated procedure, respectively. Furthermore, the assembly of these materials can vary the relative distance from other simulated planes and layers to provide different workspaces during the simulated TME procedure. According to various embodiments, the TME surgical simulator creates a challenging surgical environment with room for error, promoting the development of the scrutiny, anatomical, and surgical knowledge needed to successfully perform and evaluate performance on a simulated TME procedure. Furthermore, strategic placement of attachment points or sites generates visual and tactile feedback during the simulated anterior dissection.

[0046] According to various embodiments, the simulated tissue structures can be molded from a conductive material that utilizes visual indicators such as color as opposed to utilizing visual indicators such as texture. Thus, incisions in the wrong plane can be identified by a change in color upon entry into the various simulated tissue layers. In various embodiments, the simulated incisions in the wrong plane involve the incorporation of structural supports into the frame of the surgical simulator to widen the lateral sides of the colon / rectum assembly. This incorporation can more closely simulate the easier incisions encountered in the wrong incision plane and can provide additional simulated air insufflation, i.e., provide the surgeon with a larger simulated surgical workspace. In various embodiments, these structural supports are made of a hard plastic or a soft material such as silicone that creates strong adhesive points with other simulated tissue structures.

[0047] The TME surgery simulator, according to various embodiments, provides the surgeon with sufficient visual and tactile feedback during the simulated procedure. Additionally, the TME surgery simulator can be modified to adjust the level of difficulty of the simulated incision it provides. For example, the level of difficulty of the simulated TME procedure can be adjusted to meet clinical needs by increasing or decreasing the amount of fibrous tissue, adhesive, and / or silicone material.

[0048] A mock incision is performed from the laparoscopic approach to create a circumferential incision around the mesorectum. This incision is performed in the Holley plane to free the fatty mesorectal envelope from surrounding structures. Circumferential mobilization of the mesorectum continues down to the pelvic floor, where the rectum is separated at its distal end. Due to the curvature of the sacrum, visualization of the incision from the laparoscopic end is limited; therefore, a transanal approach can be used to create the circumferential incision around the mesorectum. The incision from the transanal end and the laparoscopic end can allow for complete mobilization of the colon. The colon is then transected proximally, after which the specimen is removed. After removal, the specimen is evaluated for any exposure of the mesorectal tear and rectal wall. A complete dissection will reveal a smooth surface with the entire outer envelope and a confined volume surrounded by an intact mesorectum.

[0049] In various embodiments, the simulated mesorectal structure is made of soft silicone and a gel-like material. The posterior side 64 of the balloon or outer shell formed from the simulated mesorectal structure is larger than the anterior side 63, and / or has a tapered diameter at both the proximal and distal ends, with the tapered diameter being more pronounced at the distal end. In various embodiments, the simulated mesorectal structure includes an outer membrane that constitutes the balloon, which simulates the fascia propria surrounding the fatty envelope. In various embodiments, the membrane is a thin balloon layer made of a composite of silicone and a fibrous material, allowing for additional silicone layers to be circumferentially adhered using silicone as an adhesive. In various embodiments, the mesorectal fat filler is sufficiently gel-like, soft, and / or flowable to partially leak or spill through the outer membrane upon puncture or cutting to simulate the anatomical mesorectum when punctured, yet still function to maintain its shape within the simulated mesorectal balloon envelope. Furthermore, the simulated sample is sufficiently fragile to be accidentally broken by laparoscopic scissors, grasping forceps, or dissectors during simulated separation of the distal ends of the colon and mesorectum for its removal. In various embodiments, due to the consistency and / or amount of fat filler filling the simulated mesorectum / mesentery, the excised simulated mesorectal sample will have visible pores or ridges indicating where material has leaked. The fibrous material creates structure within the gel material that prevents unrealistic expulsion of the gel from any given puncture site. The simulated sample can then be scored and evaluated. A grade for the simulated specimen can be assigned on a scale of 1 to 3, where 3 is a complete dissection where the simulated mesorectum is intact without any perforation and / or tear, 2 is an incomplete dissection with minimal tear and / or perforation, and 1 is an incomplete dissection with puncture, tear, and exposure of the rectal wall.

[0050] In various embodiments, the simulated mesorectal structure is filled with a fat filler 61, such as soft or dense foam, silicone, conductive material, gelatin, and various gels such as Kraton®. The simulated sample can have a thin outer membrane, which can be made of gel, conductive material, or foam, or the simulated sample can have no outer layer if the simulated mesorectal structure has the strength to retain its shape.

[0051] In various embodiments, the simulated mesorectum does not simulate tissue properties, but instead is scored by color patterns and markings created on the simulated specimen during the simulated dissection. Such embodiments may include a molded component made of a certain color of foam, silicone, or another soft material to resemble the shape of the mesorectum. This molded component may be tightly wrapped or covered with a silicone sheet of a contrasting color. In various embodiments, if the simulated specimen is punctured during the simulated dissection, the exposure of the component color may indicate a tear or puncture.

[0052] The simulated mesorectum, according to various embodiments, provides realistic tactile and visual feedback to the user while performing a simulated TME procedure, along with the ability to evaluate the user's surgical technique. Furthermore, like a specimen extracted from a patient, the simulated mesorectum can be scored upon extraction. Furthermore, the simulated mesorectum, according to various embodiments, is produced with an outer silicone sheet, which allows for adhesion to other silicone and fibrous components within the TME surgical simulator.

[0053] In various embodiments, the anterior mesorectal incision is simulated by creating various planes made of thin silicone sheets and fibrous materials, e.g., padding. The simulated mesorectum and simulated mesentery 57, 58 are continuous structures distinguished from the surrounding tissue by color and texture. In various embodiments, the sheets making up the mesorectum and mesentery envelope are similar in color to the surrounding tissue. In various embodiments, the mesentery and mesentery are filled with a fat filler 61, e.g., a yellow gel substance that simulates fat. The presence of this yellow gel behind the silicone envelope that forms the outer border of the mesentery and mesentery imparts its color to these structures. The simulated incision in the correct plane is identified by simulated anatomical landmarks, such as the bladder, seminal vesicles, prostate, and ureters. In various embodiments, these simulated organ structures are made of silicone and foam materials. The simulated mesorectum 58, simulated mesentery 57, simulated bladder 44, and simulated ureter 42 are assembled to allow the surgeon to identify these landmarks to complete the simulated TME procedure. In various embodiments, circumferential dissection of the mesorectum in the correct dissection plane, the Holley plane, is simulated by creating a cylinder made of a composite of a thin silicone sheet and padding. This thin silicone sheet is described above as a simulated retroperitoneum with a thin layer of fibrous material, such as padding, attached to it to simulate the Holley plane of dissection. In various embodiments, the simulated mesorectum and the thin silicone sheet creating the simulated retroperitoneum, referred to as the incorrect plane in the lower pelvis, are distinguished by color and texture, and by the simulated Holley plane, which is located between and separates the two and indicates the correct path for circumferential simulated dissection around the simulated mesorectum. The locations of landmarks such as nerves, ureters, and gonadal vessels are useful for this dissection aspect of the simulated TME procedure and are identified by their location beneath the retroperitoneum. The inclusion of a simulated nerve 34 and a simulated ureter 42 glued or otherwise attached to the posterior side of the simulated tort / endopelvic fascia layer 41 allows the surgeon to verify that they are dissecting in the correct plane.

[0054] The simulated tort / endopelvic fascia layer 41 forms a tissue plane around the mesorectum 58, and in various embodiments using strategic placement of adhesive, silicone, and / or other similar attachments ensures proper visualization of the appropriate simulated landmarks. In various embodiments, variations on the technique for simulating circumferential dissection include using more or less silicone, foam, or padding material to create thicker or thinner planes, respectively, to decrease or increase the level of difficulty of the simulated procedure. To create more difficult circumferential dissections through the plane of Holly, additional adhesive, stronger silicone adhesion, and / or a type of attachment similar to the attachment of the simulated tort / endopelvic fascia layer 41 to the simulated mesorectum 58 can be used. In various embodiments, the difficulty of dissections in the plane of Holly and the false dissection plane can be adjusted by modifying the amount of pressure used to adhere these planes together. Additionally, the difficulty of dissecting within the Holley and false dissection planes can be adjusted by varying the size of the tissue planes relative to the adjacent outer surfaces. For example, by reducing the overall surface size of the Tolt's fascia / visceral peritoneum / endopelvic fascia ("Tolt / endopelvic fascia") layer compared to the pelvic floor layer, there is more outward stretch or tension within the Tolt / endopelvic fascia layer, and therefore more force pulling this layer inward as the user dissects the pelvis, making it easier to dissect through the false dissection plane that exists between the Tolt / endopelvic fascia and the pelvic sidewall.

[0055] By varying the fibrous material and / or attachments, such as the amount and / or type and pressure of silicone adhesive, and / or any combination thereof, the difficulty of dissection within the Holley plane and / or mis-plane can be controlled and / or varied. However, it should be noted that such adjustments or variations may disrupt or modify the surgical simulator's tactile and / or visual feedback. Therefore, a balance of the fibrous material and / or attachments may be required or can be adjusted to properly provide the desired dissection difficulty or challenge, as well as the visual / tactile feedback. It should also be noted that the size, shape, uniformity, and / or divergence of the depicted Holley plane and / or mis-plane have been exaggerated for ease of depiction and interpretation. The fibrous material, adhesive, and / or the like may, for example, extend over or otherwise occupy all or portions of the dissection plane. The dissection plane may become significantly or otherwise separate during the simulated dissection of the surgical simulator.

[0056] In various embodiments, the use of conductive materials for the simulated mesorectum 58 and simulated tort / endopelvic fascia layer 41 can enable the use of energy during this segment of the simulated TME procedure. Additionally, the assembly of these materials can be varied so that the relative distance from other simulated planes and simulated tissues provides a larger or tighter working space during the simulated TME procedure. Additionally, the outward tension resulting from the stretching and attachment of the various layers or assemblies simulates the effect of insufflation on dissections within the pelvic cavity. Due to the use of insufflation in real procedures when a surgeon performs a circumferential dissection around the mesorectum within the pelvic cavity, pressure from the insufflation gas tends to separate the tissue planes as the surgeon creates a cut within the dissection plane and performs blunt dissection.

[0057] Additionally, in this surgical simulator, the adhesion of the silicone simulated mesorectum to the simulated silicone visceral peritoneum layer through the padding layer provides room for puncture and tearing of the simulated mesorectum that cannot be achieved based on the use of various materials that do not adhere to silicone.

[0058] In various embodiments, there is a distinct shape of the simulated mesorectum 58, which is curved and bulges more posteriorly, following the curvature of the sacrum, while remaining thinner anteriorly toward the pubic bone. In various embodiments, a transanal approach for a simulated TME procedure can be used to mobilize the rectum and mesorectum within the lower pelvic region. In this approach, the surgeon uses a transanal access system, which is a platform and / or channel for accessing the rectum, creating a purse string suture, and closing the rectum. To achieve access to the Holly plane, a circumferential incision is created around the purse string suture. Access to the Holly plane from a transanal approach requires significant skill and anatomical knowledge. In various embodiments, a simulated transanal adapter is used to achieve access into the simulated rectum. The transanal adapter allows the surgical simulator to interface with a simulated laparoscopic trainer. The adapter includes rigid components that lock onto the top and bottom bodies of the trainer. The rigid components can be manufactured from urethane or plastic. Molded into the adapter is a soft silicone layer that encloses a small opening that simulates the anus into which the access platform can be mated. The material variations that simulate the anus and the skin around the adapter can include soft rubbery materials or rigid materials. The use of soft materials provides flexibility and the ability to manipulate access instruments within the simulated orifice. In various embodiments, the use of silicone allows for the use of strong silicone-to-silicone bonds when mated with additional silicone components found within the simulated TME surgery simulator.

[0059] According to various embodiments, at the distal end of the simulated TME surgical simulator, the simulated rectum 53 extends beyond the frame so that it can be positioned around the access channel that is threaded through the orifice of the adapter described above. In various embodiments, the diameter of the rectum is smaller than the access channel, allowing the rectum to stretch around the channel and remain stationary. In various embodiments, the simulated rectum can be glued or otherwise attached directly to the silicone portion of the adapter. Thus, the access channel is inserted through both the adapter and the colon simultaneously, which may be challenging for the user due to the size difference that allows for a tight pressure fit. The extension of the rectum at the distal end, which is larger than the frame of the surgical simulator and larger than the circumferential incision layer, provides sufficient length for the access channel to remain in place. In various embodiments, the frame and / or incision layer can extend adjacent to the adapter. This further makes the surgical simulator more rigid and less mobile at the distal end, which is anatomically unrealistic.

[0060] With the access channel in place, laparoscopic instruments can be used to encounter the lumen of the simulated colon and create a purse string suture. In various embodiments, a mesh can be embedded within the simulated rectum 53 to make the tear strength of the simulated rectum 53 high enough or strong enough to withstand the forces generated by the sutures. In various embodiments, the rectum is simulated without the use of a mesh and / or in combination with a mesh, using additional materials to increase the strength of the rectum to hold the sutures. Additional materials can include silicone, Kraton, other rubber-like materials, and / or combinations thereof. With the purse string suture created, the lumen of the simulated colon is closed, exposing a circumferential dissection layer around the rectum.

[0061] According to various embodiments, at the distal (anal) end, the rectum is followed by a mesorectal fat filler 61 encased in a silicone envelope, and the outermost layer of the mesorectal silicone balloon or envelope is glued or otherwise attached to a Tolt / endopelvic fascia sheet or layer. The plane of dissection between the mesorectum and the endopelvic fascia represents the plane of Holley. In various embodiments, the simulated endopelvic fascia sheet 41 is a thin yellow layer referred to as the retroperitoneum within the pelvic cavity during a simulated laparoscopic procedure. Between the endopelvic fascia and the pelvic sidewall is another layer of fibrous material that creates or represents the incorrect plane of dissection. Surrounding this fibrous layer is a pink silicone layer that visually represents the pelvic floor / pelvic sidewall. These layers are glued or otherwise attached to each other so that upon placement of the purse string sutures, the simulated rectum and simulated mesorectum are tightened to allow access to the correct (Holey) and incorrect (incorrect) planes 71, 73 for the simulated dissection. These dissection planes occur between the mesorectum and the endopelvic fascia and between the endopelvic fascia and the pelvic sidewall. During simulated circumferential dissection of the simulated mesorectum from a transanal approach, it is easy to enter the wrong plane 73 due to the pinching of the apex of the simulated planar tissue layer of the surgical simulator at the distal end of the mesorectum. This creates a confined working environment and simulates what the patient sees. Wrong planes can be entered from a transanal approach, and entry into the wrong plane can be visualized by tactile feedback between changes in color and texture and the ease of dissection between these planes. Holly's planes have more difficulty and / or a greater tactile response compared to dissections through the wrong planes. In various embodiments, this tactile feedback response is simulated through variations in adhesion or attachment between the fibrous layers extending into or between these planes.

[0062] According to various embodiments, the transanal approach may vary in the shape of the simulated pelvic structure, which may be modified to create a smaller or larger working environment and / or vary the proximity of simulated tissue layers and landmarks to modify the level of difficulty of the simulated TME procedure. In various embodiments, the simulated transanal approach may further involve the incorporation of additional structural supports into the frame to allow for improved tissue structure mating and simulated air insufflation, providing the surgeon with a greater amount of simulated surgical workspace. In various embodiments, these structural supports may be fabricated from a hard plastic or a soft material such as silicone that creates strong attachment points with other simulated tissue structures made of silicone. The simulated transanal approach of the TME surgery simulator, according to various embodiments, provides a sufficient challenge in completing the simulated TME procedure by creating a confined working environment similar to the confined space found within the pelvic cavity, allowing room for entry in the wrong plane, which is a learning objective for the TME procedure. Additionally, the simulated rectum 53 holds the purse string suture long enough for the surgeon to close the rectum and enter the Holley plane. In various embodiments, the simulated mesorectum is narrowed at the transanal end of the TME surgical simulator to resemble or simulate the narrowed diameter of the mesorectum in a patient. In various embodiments, the simulated mesorectum 58 does not have a narrowed portion at the transanal end, but resembles or simulates the expanded portion of the mesorectum found in a patient. In a similar variation, the mesorectum can enclose the rectum with the same thickness of the fat envelope across the rectum. In various embodiments, the narrowed diameter of the mesorectum at the transanal end allows access in the Holley plane within the tight working space of the transanal end of the surgical simulator, while also providing the ability to enter the wrong plane if the user is overly aggressive in their dissection.

[0063] The narrow pelvis in male patients can present a challenge to surgeons reaching the pelvic floor via a laparoscopic approach after a full circumferential dissection of the mesorectum. Therefore, in various embodiments, the TME surgery simulator provides a simulated pelvic structure, e.g., a frame / housing 20, 20', that supports simulated tissue structures and creates a confined working environment that simulates the natural curvature of the pelvis. In various embodiments, as shown in FIGS. 18-20 , the frame 20' includes a plastic sheet 29 that is cut, folded, and assembled to resemble, in various embodiments, the deep sacral curvature of the pelvis. This curvature creates limited visualization during dissection and thus provides another simulated feature within the TME surgery simulator. In various embodiments, the plastic sheet is bonded to a thick silicone sheet through openings in the frame sheet. These silicone sheets do not function as anatomical features, but instead are used to secure simulated tissue structures, e.g., silicone tissue components, to the plastic frame component. In various embodiments, silicone is used to bond the silicone tissue structure to a silicone sheet bonded to the frame component, forming a durable silicone bond that strengthens or enhances the TME surgical simulator. Similarly, in various embodiments, the simulated tissue structure is also adhered or otherwise attached to a dome-shaped fastener 28, which is further fastened or otherwise attached to the frame to provide tension on the simulated tissue structure. The outward extension, stretching, and / or tension, e.g., circumferential tension, of the simulated tissue can further simulate the insufflation provided during a laparoscopic procedure.

[0064] During surgery, insufflation gas stretches tissue planes within a patient's body. Thus, as the surgeon creates a cut in the tissue, the tension created by the insufflation gas pulls tissue planes away from each other. This is especially evident when the surgeon moves from the abdominal cavity to the pelvic cavity. This is also part of the reason why it is so easy to enter the wrong dissection plane and then continue in the wrong plane when the dissection continues into the pelvis. Therefore, in various embodiments, simulated tissue structures within a TME surgical simulator, particularly within the pelvic cavity, are placed under circumferential tension as a way to simulate the behavior of tissue planes under tension as a result of insufflation.

[0065] In various embodiments, the frame is made of a thin plastic sheet that adds flexibility and allows for the creation of a simulated pelvic curvature without the need for additional bends, cuts, sheets, and fasteners. Furthermore, in various embodiments, the silicone sheet used for assembly can be adhered to the frame using adhesives and / or fasteners. According to various embodiments, the frame provides a challenging, confined working environment, including limited visibility during the posterior incision through the Holley plane. Furthermore, in various embodiments, the frame provides simulated air to the surgical simulator and also creates support that can be utilized to manipulate the level of difficulty of the surgical simulator by widening or narrowing the working environment. In various embodiments, the modularity of the frame, which is assembled from at least two members or components, facilitates assembly of the TME surgical simulator.

[0066] In various embodiments, the final assembly of the TME surgical simulator begins with the colon / rectum / mesentery / mesorectum assembly, which is the innermost assembly within the TME surgical simulator. The Tolt / endopelvic fascia assembly is attached around the mesorectum / rectum assembly, and then the prostate assembly is added, followed by the pelvic floor attached to / around the Tolt / visceral peritoneum / endopelvic fascia. After a soft layer is glued or otherwise attached in place around the mesorectum, a plastic / silicone component that joins the soft subassembly to the frame is attached in place to the final soft subassembly. This silicone subassembly is such that its outer surface is slightly smaller than the inner surface that will later be achieved when the plastic frame components are finally assembled. This size mismatch between the silicone subassembly and the layers within the plastic frame results in circumferential tension on all tissue layers within the surgical simulator's pelvic cavity. In various embodiments, this circumferential tension is a feature of the surgical simulator that provides simulated air insufflation, further improving the realism of the simulation.

[0067] According to various embodiments, assembly of the TME surgical simulator begins with a fully assembled frame 20′ or a single monolithic frame 20. Within the frame, a pelvic floor / sidewall assembly is glued or otherwise attached. A Tolt's fascia / visceral peritoneum / endopelvic fascia (“Tolt / endopelvic fascia”) layer is glued or otherwise attached to the pelvic floor / sidewall, and within the Tolt / endopelvic fascia layer 41, a mesorectum / mesentery / colon / rectum assembly is glued or otherwise attached. When attached in such a manner, each successive layer is under outward tension. This outward tension pulls the layers or subassemblies away from each other as an incision is made between them, thereby providing a faithful simulation of what occurs within a patient due to the tension generated by insufflation gases during laparoscopic dissection.

[0068] In various embodiments, a frame is formed with simulated assemblies already adhered together, such as a simulated mesorectum 58 or endopelvic fascia layer 41, and outward circumferential tension is achieved when portions of the frame are attached to the outermost layers of these simulated assemblies. Because the frame is larger than the simulated assemblies or layers, these simulated layers stretch as the frame is assembled or formed. This stretching that occurs during assembly of the frame imparts this outward tension to the attached simulated tissue assemblies. This outward tension simulates insufflation without the use of insufflation gas or a sealed enclosure.

[0069] As a result of this pre- or initial outward tension, the corresponding simulated assemblies or layers tend to separate when the simulated incision is made, simulating the effects of air insufflation. For example, during the simulated incision, one or more outer layers attached to the frame may remain fixed or may tend to move outward or away from one or more inner layers due to the release of the weight of the inner layer, contraction or tendency of the material to move toward the frame, and / or a combination thereof. The inner layer, once separated from the outer layer, is released from the outward tension and therefore moves or tends to move inward or away from the outer layer. The weight of the inner layer, contraction or tendency of the material to return to a non-tensioned or pre-stretched state, and / or a combination thereof can further move the inner layer away from the outer layer.

[0070] In various embodiments, the pre-generated outward tension is created when each simulated assembly or layer is formed. For example, each simulated assembly is subjected to outward tension when it is attached to a frame or to the immediately preceding simulated layer between the simulated assembly and the frame. Thus, each simulated assembly is pre-stretched and then attached to the immediately preceding simulated layer or frame. In this manner, when these simulated assemblies or layers are added to the surgical simulator, tension is added to the layers, resulting in them being less strong, more susceptible to breaking when separated, and / or overly bonded or attached to other simulated layers or frames. In this method, adhesive is added to the layers while they are in a pre-stretched state and under pressure; the amount of adhesive and pressure can be controlled independently of layer size, but all properties, along with the amount of padding, must be balanced to achieve the desired incision quality.

[0071] In various embodiments, the fibrous material can be thickened or thinned to affect the overall feel of the incision and surgical simulator. The simulated assembly, e.g., the endopelvic fascia layer, can be thickened, including a moist silicone layer, one or more layers that provide a waterproof barrier, and one or more layers that provide bonding to the fibrous material. Thicker silicone layer(s) can make the simulated incision easier, as it is more difficult to damage or mishandle the simulated assembly with surgical instruments. Additionally, thicker silicone can provide more outward tension compared to thinner layers of the same size and shape.

[0072] 11A-11B, to illustrate exemplary configurations in which simulated endopelvic fascia 41 is not stretched or only minimally stretched or otherwise tensioned and simulated mesorectum 58 is significantly stretched or otherwise tensioned compared to simulated endopelvic fascia 41 according to various embodiments of the present invention, a configuration before stretching / tensioning is shown in FIG. 11A and a configuration after stretching / tensioning is shown in FIG. 11B. In such a configuration, a dissection in Holly's plane 71 is easier than one in the wrong plane 73 because simulated mesorectum 58 will attempt to separate from simulated pelvic lining 41 due to attempting to return to its pre-stretched or unstretched configuration. An easier Holly's plane dissection is less challenging or less difficult for a training surgeon because the training surgeon is more likely to dissect in the "correct" Holly's plane instead of the wrong plane.

[0073] 12A-12B, to illustrate exemplary configurations in which the simulated mesorectum is not stretched or only minimally stretched or otherwise tensioned and the simulated endopelvic fascia 41 is significantly stretched or otherwise tensioned compared to the simulated mesorectum 58, a configuration before stretching / tensioning is shown in FIG. 12A and a configuration after stretching / tensioning is shown in FIG. 12B. In such a configuration, dissection in the wrong plane 73 is easier than in Holley's plane 71 because the simulated mesorectum 58 will not attempt to separate from the simulated pelvic lining layer 41 and will have no or only minimal tendency to bias it inward or away from the simulated endopelvic fascia layer 41. Meanwhile, the simulated pelvic lining layer 41 will attempt to return to its pre-stretched or unstretched configuration and will therefore attempt to separate from the simulated pelvic floor or toward the simulated mesorectum 58. The easier wrong plane incisions are more challenging or more difficult for the training surgeon because the training surgeon may incise in the wrong plane instead of the "correct" Holley plane.

[0074] Referring to FIG. 13 , a neutral or no / minimal stretch / tension configuration is shown to illustrate an exemplary configuration in which the size of the simulated mesorectum and simulated endopelvic fascia layers 58, 41 match the size of the frame and the thickness of the previous simulated layer so that they are adhered or otherwise attached in place without being placed under outward tension or stretching. According to various embodiments, in this regard, the difficulty of dissection is controlled or adjusted solely by fibrous material, pressure, adhesives / attachments, and / or combinations thereof, since the layers are not under outward tension and therefore do not tend to separate from one another or are not preconditioned to do so. In various embodiments, for example, as shown in FIG. 8B , the simulated endopelvic fascia and simulated mesorectum layers 41, 58 are stretched or otherwise tensioned such that a simulated insufflation effect exists in both the Holley plane 71 and the false plane 73. Thus, in various embodiments, the simulated endopelvic fascia layer 41 is stretched or otherwise tensioned more than the simulated mesorectum 58 so that a false plane dissection is slightly easier, but the simulated mesorectum is still stretched.

[0075] In various embodiments, as one of the final steps, mesorectal fat filler 61, e.g., a preformed non-liquid fat filler, is injected or otherwise introduced into the mesorectum / mesentery. As a result, the fat filler does not adversely affect the process of bonding or otherwise attaching the simulated tissue layers to one another, and in particular, strengthens the attachment between the mesorectum and endopelvic fascia, allowing for accurate simulation of the Holley incision plane between these two layers. Furthermore, in various embodiments, the outer layer of the mesorectum is made very thin and fragile, for example, it can be fabricated from a thin, fragile silicone sheet, thereby improving the realism of the TME surgical simulator and its ability to be used for evaluation purposes.

[0076] In various embodiments, the simulated fat filler comprises sodium polyacrylate, opaque agar gel, water, and / or combinations thereof. It should be noted that gelatin and agar gel can be used for the mesorectal fat filler. However, gelatin melts at low temperatures (e.g., about 35°), thus limiting its usefulness, and agar gel exhibits syneresis when disrupted, which causes unrealistic leakage of water from the mesorectum when the mesorectum is damaged.

[0077] It should be noted that the various figures are presented in a semi-schematic style to facilitate identification and description of the TME surgical simulators, and therefore, the TME surgical simulators presented herein may not be intentionally uniform in location and / or spacing between simulated structures as shown in these figures.

[0078] In various embodiments, the surgical simulator includes a simulated parietal peritoneum layer and a simulated mesorectal and mesenteric layer connected to the simulated parietal peritoneum layer and forming a shell therebetween. In various embodiments, the surgical simulator further includes a simulated fat filler disposed within the shell. In various embodiments, the simulated fat filler includes sodium polyacrylate, agar gel, and / or gel. In various embodiments, the simulated mesorectal and mesenteric layer is puncturable and / or made of a thin puncturable silicone sheet.

[0079] In various embodiments, the surgical simulator includes a frame having a proximal portion defining a simulated abdominal cavity and a distal portion defining a simulated pelvic cavity. In various embodiments, a simulated endopelvic fascia layer is positioned within the simulated pelvic cavity, and a simulated pelvic floor layer is attached to the simulated endopelvic fascia layer and the distal portion of the frame. In various embodiments, a simulated mesorectal layer is attached to the simulated endopelvic fascia layer. In various embodiments, the simulated mesorectal layer and the simulated endopelvic fascia layer define a simulated dissection plane therebetween.

[0080] In various embodiments, the simulated endopelvic fascia layer, the simulated pelvic floor layer, the simulated mesorectal layer, and / or any combination thereof are placed under circumferential tension, stretched, pre-stretched, and / or pre-tensioned. In various embodiments, the simulated endopelvic fascia layer is larger than the simulated pelvic floor layer. In various embodiments, the simulated endopelvic fascia layer is thicker and / or longer than the simulated pelvic floor layer.

[0081] In various embodiments, the surgical simulator includes a frame having a proximal portion defining a simulated abdominal cavity and a distal portion defining a simulated pelvic cavity. In various embodiments, a simulated visceral peritoneum layer is disposed within the simulated abdominal cavity. In various embodiments, a simulated parietal peritoneum is attached to the simulated visceral peritoneum layer and the proximal portion of the frame. In various embodiments, a simulated mesenteric layer is attached to the simulated visceral peritoneum layer. In various embodiments, the simulated mesenteric layer and the simulated visceral peritoneum layer define a simulated incision plane therebetween.

[0082] In various embodiments, the surgical simulator includes a simulated endopelvic fascia layer and a simulated mesorectal layer, at least one of which is placed under circumferential tension, stretched, pre-stretched, and / or pre-tensioned. In various embodiments, the surgical simulator includes a simulated mesorectal layer and a simulated parietal peritoneal layer connected to each other to form a shell therebetween, and a simulated fat filler disposed within the shell. In various embodiments, the surgical simulator includes a simulated endopelvic fascia layer and a simulated mesorectal layer, the simulated endopelvic fascia layer attached to the simulated mesorectal layer to define a simulated dissection plane therebetween. In various embodiments, the surgical simulator includes a simulated visceral peritoneum layer and a simulated mesentery layer, the simulated visceral peritoneum layer attached to the simulated mesentery layer to define a simulated dissection plane therebetween. In various embodiments, the surgical simulator includes a simulated pelvic floor layer and a simulated mesorectal layer, the simulated pelvic floor layer attached to the simulated mesorectal layer to define a simulated incision plane therebetween. In various embodiments, the surgical simulator includes a simulated pelvic layer and a simulated mesentery layer, the simulated pelvic floor layer attached to the simulated mesentery layer to define a simulated incision plane therebetween. In various embodiments, the surgical simulator includes a first composite silicone sheet connected to a second composite silicone sheet. In various embodiments, at least one of the first or second composite silicone sheets is placed under circumferential tension, stretched, pre-stretched, and / or pre-tensioned. In various embodiments, the surgical simulator includes a silicone sheet connected to a composite silicone sheet, defining a simulated incision plane therebetween. In various embodiments, the surgical simulator includes a first composite silicone sheet connected to a second composite silicone sheet, defining a simulated incision plane therebetween. In various embodiments, the surgical simulator includes a silicone sheet connected to a composite silicone sheet to form a shell therebetween, and a simulated fat filler disposed within the shell, hi various embodiments, the surgical simulator includes a silicone shell and a gel including at least one of sodium polyacrylate and opaque agar.In various embodiments, the simulated fascia layer is a simulated endopelvic fascia layer, a simulated Tordt's fascia / visceral peritoneum layer, a simulated Tordt's fascia, a Tordt / endopelvic fascia layer, and / or any combination thereof. In various embodiments, the surgical simulator does not include a frame or base, and / or in various embodiments, includes one or more simulated structures and components, etc., without a frame, etc.

[0083] The foregoing description is presented to enable any person skilled in the art to make and use the invention and practice the methods described herein, and sets forth the best modes contemplated by the inventors for carrying out the invention. However, various modifications will remain apparent to those skilled in the art. These modifications are contemplated to be within the scope of this disclosure. It is understood that different embodiments and aspects of such embodiments are shown in the various figures and described throughout this specification. However, it should be noted that although each embodiment and aspect thereof is shown or described separately, it can be combined with one or more of the other embodiments and aspects thereof, unless expressly stated otherwise. The fact that each combination has not been explicitly shown is solely to facilitate the readability of this specification.

[0084] While the present invention has been described in certain specific aspects, many additional modifications and variations will be apparent to those skilled in the art. It is therefore to be understood that the present invention can be practiced other than as specifically described, including various changes in size, shape, and materials, without departing from the scope and spirit of the invention. That is, the embodiments of the present invention should be considered in all respects as illustrative and not restrictive.

Claims

1. A surgical simulator, The frame and a plurality of simulated tissue layers configured to simulate a plurality of tissue layers within a pelvic cavity, the plurality of simulated tissue layers being disposed within the frame and attached to one another; Equipped with two adjacent simulated tissue layers of the plurality of simulated tissue layers are configured to define an incision plane and are separable from one another; A surgical simulator, wherein one or more of the plurality of simulated tissue layers are configured with outward tension to simulate air insufflation.

2. A surgical simulator as described in claim 1, wherein the two adjacent simulated tissue layers of the plurality of simulated tissue layers that are configured to be separable from each other are more easily separated along the incision plane than a set of adjacent simulated tissue layers of the plurality of simulated tissue layers that do not define the incision plane.

3. A surgical simulator as described in claim 2, wherein adjacent sets of simulated tissue layers among the plurality of simulated tissue layers that do not define the incision plane are attached to each other using adhesive.

4. 4. The surgical simulator of claim 1, wherein the plurality of simulated tissue layers includes a simulated endopelvic fascia layer, a simulated mesorectal layer, and a simulated pelvic floor, and the surgical simulator is configured for a simulated surgical procedure corresponding to a simulated total mesorectal excision (TME) procedure.

5. The surgical simulator of claim 1 , further comprising a fat filler encapsulated within the plurality of simulated tissue layers.

6. The surgical simulator of claim 5 , wherein at least one of the plurality of simulated tissue layers forms a balloon containing the fat filling.

7. 7. The surgical simulator of claim 6, wherein the balloon comprises a composite of silicone and fibrous material, and the balloon is configured to be circumferentially attached to other silicone-based simulated tissue layers of the plurality of simulated tissue layers.

8. The surgical simulator of claim 6 , wherein the fat filling is configured to leak or escape when a portion of the balloon is punctured.

9. 9. The surgical simulator of claim 8, wherein the fat filling is gel-like and configured to maintain its shape within the balloon simulating the mesorectum even when the balloon is punctured.

10. The surgical simulator of claim 8 , wherein the fat filling further comprises a fibrous material.

11. The surgical simulator of claim 9 , wherein the balloon is configured to be removed from the plurality of simulated tissue layers.

12. 5. The surgical simulator of claim 1, further comprising one or more simulated organs including a simulated rectum, a simulated ureter, a simulated colon, a simulated prostate, and a simulated gonadal vasculature.

13. 3. The surgical simulator of claim 2, wherein a set of two simulated tissue layers of the plurality of simulated tissue layers further comprises a fibrous material, and separation of the set of two simulated tissue layers of the plurality of simulated tissue layers comprising the fibrous material is more difficult than separation of the two adjacent simulated tissue layers of the plurality of simulated tissue layers that define the incision plane.

14. The surgical simulator of claim 1 , wherein one or more of the plurality of simulated tissue layers comprises a conductive material configured for electrosurgical energy-based dissection.

15. 5. The surgical simulator of claim 1, wherein the plurality of simulated tissue layers are configured to have portions with different textures, a first portion having a first texture corresponding to the incision plane, and a second portion having a second texture not within the incision plane.

16. The surgical simulator of claim 1 , wherein one or more of the plurality of simulated tissue layers is placed under circumferential tension.

17. 17. The surgical simulator of claim 16, wherein the plurality of simulated tissue layers includes a first simulated tissue layer and a second simulated tissue layer, the first simulated tissue layer being under more circumferential tension than the second simulated tissue layer.

18. 18. The surgical simulator of claim 17, further comprising a third simulated tissue layer attached to the first simulated tissue layer, the third simulated tissue layer being attached to a simulated blood vessel and a simulated organ.

19. A surgical simulator as described in claim 1 or 4, wherein the two adjacent simulated tissue layers of the plurality of simulated tissue layers that define the incision plane comprise a simulated mesentery layer and a simulated visceral peritoneum layer, and the simulated mesentery layer and the simulated visceral peritoneum layer define the incision plane.

20. A surgical simulator as described in claim 1, wherein the two adjacent simulated tissue layers of the plurality of simulated tissue layers that define the incision plane comprise a simulated pelvic floor layer and a simulated mesorectal layer, and the simulated pelvic floor layer and the simulated mesorectal layer define the incision plane.

21. A surgical simulator as described in claim 1 or 4, wherein the multiple simulated tissue layers further include a simulated visceral peritoneum layer and a simulated parietal peritoneum attached to the simulated visceral peritoneum layer and the frame.

22. A surgical simulator as described in claim 1 or 4, wherein the plurality of simulated tissue layers further includes a simulated mesentery layer attached to a simulated visceral peritoneum layer.

Images