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A further advance in endoscopic simulation was developed by Grund et al. at the University of Tübingen in Germany [24]. In this “Interphant” or “Phantom” model, artificial electrically conductive tissue called Artitex is used to fashion abnormalities such as polyps and strictures and incorporate this into static models. These “pathologies” are in place of the painted‐on abnormalities used in some of the pure static models mentioned above. Grund’s “Artitex” abnormalities are sewn directly into a three‐dimensional latex anatomical model (Figure 1.10a,b). While these models generally lack a realistic representation of bowel wall compliance and motility, the integrated pathology appears realistic and allows practice in electrosurgical techniques.

In order to simulate the resistance to endoscope passage in an actual procedure, this colon model uses a semiflexible series of coils. In addition, to allow for a still wider possibility of simulated techniques, Grund’s model can incorporate real animal tissue into the existing framework. For example, using a chicken heart, they can fashion an ampulla of Vater replete with separate pancreatic and biliary orifices and insert this into their upper endoscopy simulator (Figure 1.10b). The advantage of using this type of system is that several “polyp‐laden” colons and “chicken‐heart papillae” can be prepared in advance and quickly inserted into the chassis of the model during a training session, after the initially prepared material has been depleted.

The Tübingen simulators made possible the teaching of polypectomy and provided an excellent means of teaching therapeutic procedures such as argon plasma coagulation and simple therapeutic ERCP. In particular, the orientation of the man‐made papilla more closely resembled that of humans than the porcine papilla found in the Erlangen models described below. Pancreatic cannulation and endotherapy was possible, in contrast to the porcine tissue models in which the pancreatic orifice was not readily accessible. However, procedures that required submucosal injection were still not feasible.

Figure 1.10 (a) Artificial tissue colonoscopy “Phantom” simulator, U. of Tübingen. (b) Combined artificial tissue “Phantom” upper GI simulator with integrated chicken heart tissue papilla for ERCP simulation.

While this model represented a technological advance over prior static models and added many new capabilities, there remained several limitations that hindered its more widespread use in training. The main drawbacks were that the pathology remained hand‐prepared and that the models were not mass‐produced. Therefore, the “Phantoms” have not been readily available and have required the presence of the Tübingen team if the device was to be used at a training course. The trade‐off for increased realism and the ability to start practicing therapeutic manipulations were significant increases in the logistical and cost obstacles to widespread use. Furthermore, models combining the real tissue abnormalities of the Tübingen model with the more accessible ex vivo animal tissue simulators described below now exist.