Patent Application
20080032273
The following disclosure relates to anatomical models, and in particular to models for simulating internal body cavities.
Anatomical models are well known devices for teaching doctors or other medical personnel about the human body. Such models are often made of plastic or latex and are shaped to simulate the structure of human bones, organs, or other anatomical systems and structures. The models are used to allow students to identify various body parts as well as to practice medical procedures prior to use on a living patient. In addition, such models are often used by medical device developers in order to test various designs and/or aspects of medical devices.
One such anatomical model is a model of a human colon. Endoscopists and students often use such models to practice various intubation and procedure techniques inside the model. While plastic or latex models can be fashioned to have the same shape as an actual human colon, such models generally do not interact with an endoscope in the same way that actual colon tissue does, and therefore do not provide a completely realistic simulation.
The present disclosure describes an anatomical model for simulating internal body structures of a patient. In one embodiment, the model simulates a human colon. A torso shell has an inner shape that conforms to a typical human body cavity in which a colon is found. A tubular fabric sheath supports a length of colon tissue that is obtained from an animal. The colon tissue is placed in the sheath and is secured at one or more anchor points in the torso shell. An inflatable bladder pressurized to a variable pressure is placed against the colon tissue to simulate abdominal pressure on the colon. A cover seals the inflatable bladder and colon tissue in the torso shell.
In one embodiment, an artificial cecum is secured to the distal end of the colon tissue. The cecum may include one or more polyp holders that hold one or more simulated polyps so that a physician can practice removing them during a medical procedure.
In one embodiment, the anatomical model is secured to a base that includes one or more force sensors and position sensors. The sensors can measure forces on the model or the position of an endoscope as it is used in the model.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
The foregoing aspects and many of the attendant advantages of the disclosed technology will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
As shown in
In another embodiment, the sheath comprises an elastic sleeve (such as polymer sheet or natural or synthetic fabric) that is pre-shaped in the desired anatomical form with a plurality of securing features at desired locations along the geometry of the elastic sleeve. There is at least one securing feature of a desired geometry per desired location along the elastic sleeve geometry. The securing features may be of the same or different material as the elastic sleeve, and all securing features need not be of the same geometry or material. The elastic sleeve further has an enclosed, or semi-enclosed, conduit or cavity that can be accessed by various means (zipper, hook and loop, buttons, etc.) to introduce biological material to be housed in sleeve. The biological material may be in turn secured to sleeve or allowed to move freely within the cavity. The elastic sleeve is attached to the desired torso shell (or pliable cover) locations via one or many of the securing features at each attachment point along the elastic sleeve. Attaching more or less of the securing features at each site influences the elastic sleeve's mobility, or increases the force required to stretch feature with respect to torso anchor point. Securing more features would make it more difficult to stretch elastic sleeve away from anchor point. The colors of the elastic sleeve could be such that they mimic desired simulated anatomy. The pre-formed shape of the elastic sleeve can be that of bowel, or other anatomy of interest.
To simulate different colon shapes in a patient, the supporting fabric sheath 50 is secured to the inside surface of the torso shell 20 at one or more of the anchor points 26. Fasteners on the supporting sheath 50 cooperate with the snap fittings, magnets, Velcro pads, screw holes, or other fastening mechanisms on the anchor points 26 allow the colon tissue 40 to be supported at desired positions within the torso shell 20. The fasteners may be flexible to allow the sheath to move with respect to the anchor points 26 in order to simulate the response of a colon during a colonoscopy. Flexible fasteners may be made of a polymeric material such as rubber posts, bolts, rivets, wraps, or the like that are secured to the anchor points.
Returning to
In one embodiment, the inflatable bladder 100 is secured in the torso shell 20 with a cover 120. In one embodiment, the cover 120 includes a number of snap fittings that are secured to corresponding snap fittings positioned around the rim of the torso shell 20. In the embodiment shown, the cover 120 and inflatable bladder 100 are separate components. However, it will be appreciated that these components may be combined if desired. For example, the inflatable bladder may include straps that allow it to be secured to the torso shell 20.
In one embodiment of the invention, the cover 120 is made of a pliable material, such as vinyl or rubber that allows an endoscope passing through the colon tissue 40 to be felt underneath the inflatable bladder 100. By pressing on the cover 120, a nurse or other user can attempt to prevent the endoscope from looping as is done during a conventional colonoscopy procedure.
The anatomical model 10 described above also allows a determination of forces applied as a physician/trainee uses an endoscope in the colon tissue. An instrumented model allows a determination to be made of a colon model complexity based on the forces measured during intubation, extraction or during an entire colonoscopy procedure. As shown in
Signals from the transmitter/receiver pair 160, 170 and the force gauges 152, 154 can be fed to a computer system 180 to provide a real time plot of the position of the endoscope and forces on the colon tissue. Signals from the force gauges 152, 154, as well as from the position sensors 160, 170, and 190, allow the interaction forces between the endoscope and the colon to be analyzed. For example, it is possible to compare various endoscope designs for ease in trackability through the colon tissue. Similarly, readings from these sensors can be detected to alert a physician/trainee as to the likelihood that a procedure or action will cause patient discomfort or potential injury. The computer system 180 can be programmed to compare forces and/or positions of the endoscope to one or more limits and provide alarm signals or other indications to the endoscopist or trainee that too much force is being applied or that the endoscope is not in the correct position, etc. In another embodiment, force sensors are placed on both the proximal and distal ends of the endoscope. The sensors can measure axial and torsional loads at both locations and this data can be used to understand and predict how forces are transmitted through the endoscope.
Because the colon tissue 40 is harvested from an animal that closely mimics human tissue, the images observed by the physician will closely approximate those seen during a human endoscopy. Generally an endoscopist navigates his or her way around the tortuous human colon by following the darker area in their view. Therefore the model should produce images on a screen that are very similar to what a doctor will see during a human colonoscopy. Furthermore, because the tissue is wet, movement of the endoscope through the colon tissue closely simulates how the endoscope will perform during a human colonoscopy. Although colon tissue in the disclosed embodiment of the model is obtained from pigs, it will be appreciated that other animal tissue, such as from sheep, may be used.
Another advantage of the model disclosed is that it allows the colon shape to be changed. By selectively securing portions of the supporting fabric sheath to the torso shell, configurations can be set up that mimic a male colon, a female colon, or colon tissue that has undergone or is surrounded by tissue that has undergone a surgical procedure or is otherwise unusually shaped. Furthermore, the anatomical model 10 allows the colon walls to stretch by including a number of folds in the fabric sheath. The amount of stretch can also be varied by using a sheath material of different durometers in order to simulate how certain portions of the colon stretch as the colonoscope is passed through. Similarly, the anchor points or fasters that couple the sheath to the anchor points can have varying levels of elasticity to simulate looping that can occur during a colonoscopy procedure. By selectively placing anchor points for the fabric sheath in the torso, loops such as a double alpha loop or a reverse double alpha loop in the sigmoid region can be simulated. Similarly, a 3D curvature in the splenic and hepatic flexures can also be simulated. Finally, features such as restrictions, polyps, folds, etc., can be fashioned or placed into the colon walls by cutting or suturing the colon wall or by adhering objects or injecting dyes to the colon wall.
Upon completion of a training session, the anatomical model 10 can be taken apart and the colon tissue 40 disposed of. The remaining components can be cleaned for re-use.
While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the scope of the invention. For example, the anatomical model can be adapted for simulating other body cavities. Esophagus tissue from an animal such as a pig can be placed in a shell that simulates an upper respiratory cavity. Furthermore, the anatomical model described above can be used to simulate body cavities in animals in addition to humans. Such a model may be useful for veterinary students or for manufacturers of veterinary medical devices. Furthermore, the model may be used as a training and development tool for surgical endoscopy and NOTES (natural orifice transluminal endoscopic surgery) to provide realistic access and closure for physicians and trainees. Further, this invention can be used for testing of endoscopic devices such as balloons, stents and snares, etc. Therefore, the scope of the invention is to be determined from the following claims and equivalents thereof.
The present application claims the benefit of U.S. Provisional Application No. 60,815,626, filed Jun. 21, 2006, which is herein incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60815626 | Jun 2006 | US |
