Physical simulator for colonoscopy: a modular design approach and clinical validation

Simulators for gastrointestinal (GI) endoscopy offer the opportunity to train and assess clinician skills in a low-risk environment. Physical simulators can enable direct instrument-to-organ interactions not provided by virtual platforms. However, they present scarce visual realism and limited variability in their anatomical conditions. Herein, we present an innovative and low-cost methodology for the design and fabrication of modular silicone colon simulators. The fabrication pipeline envisages parametric customization and development of 3D-printed molds for silicon pouring to obtain colon segments. The size of each colon segment is based on clinical data extracted from CT colonography images. Straight and curved segments are connected through silicone conjuncts to realize a customized and modular monolithic physical simulator. A 130 cm-long colon simulator prototype with assorted magnetically-connected polyps was fabricated and laid on a custom-made sensorized abdominal phantom. Content, face and construct validity of the designed simulator were assessed by 17 GI endoscopists. In summary, this work showed promising results for improving accessibility and flexibility of current colonoscopy physical simulators, paving the way for modular and personalized training programs.