Design and validation of a cost-effective physical endoscopic simulator for fundamentals of endoscopic surgery training.

BACKGROUND: The American Board of Surgery will require graduating surgical residents to achieve proficiency in endoscopy. Surgical simulation can help residents to prepare for this proficiency test, accelerate skill acquisition, shorten the learning, and improve patient safety. Currently, endoscopic simulators are extremely cost-prohibitive. We therefore designed an inexpensive physical endoscopic simulator to (1) facilitate Fundamentals of Endoscopic Surgery skills training and (2) teach basic colonoscopy skills, for <$200.00. METHODS: We constructed the Rutgers Open Source Colonoscopy Simulator (ROSCO) from easily acquired commercial materials. For construct validation, we compared novices to experts in a two-arm non-randomized study. Each participant performed the five tasks and a full cecal intubation on the simulator. Face and content validity surveys were taken by the experts, after the construct validity study to determine the simulator's ability to achieve the intended task with "realism." Data were collected on (1) cost and construction, (2) time to completion of individual tasks, (3) percentage of task completion, and (4) survey statistics. RESULTS: Our simulator requires no advanced expertise, costs $62.77 US, and weighs 8.5 pounds. The ROSCO simulator was clearly able to distinguish expert from novice. Expert task times for completing all five tasks, performing the loop reduction, and reaching the splenic and hepatic flexures on the simulator were significantly better than novice times (p < 0.05). All participants were able to complete all five tasks on the simulator 100 % of the time. Three out of five experts "Agreed" or "Strongly Agreed" with five out of the six statements regarding the simulator's teaching ability. Four out of five experts rated each of the five specific aspects of the simulator as "Realistic" or "Very Realistic." CONCLUSIONS: We have designed a low-cost colonoscopy simulator with easily available materials and which requires very little advanced construction expertise and have demonstrated construct, face, and content validity. We believe this will have broad impact for endoscopic simulation, surgical education, and health education cost.

Routes for virtually guided endoscopic liver resection of subdiaphragmatic liver tumors.

PURPOSE: Laparoscopic and thoracoscopic/laparoscopic hepatectomy is a safe procedure that has potential advantages over open surgery. However, deeply positioned liver tumors require expert laparoscopic and thoracoscopic/laparoscopic hepatectomy techniques. Using simulated preoperative three-dimensional virtual endoscopy (P3DVE) guidance, we demonstrate herein that a thoracoscopic approach (TA), thoracoscopic-laparoscopic approach (TLA), and laparoscopic approach (LA) are all feasible and safe routes for performing pure laparoscopic and thoracoscopic/laparoscopic resection of liver tumors located in the 4a, 7, and 8 liver subdiaphragmatic areas. METHODS: Thirty-eight patients underwent laparoscopic and thoracoscopic/laparoscopic partial liver resection (TA 13 cases, TLA two cases, and LA 23 cases) of the subdiaphragmatic area at Showa University Hospital. All surgical approaches were preoperatively determined based on preoperative 3D virtual endoscopic simulation (P3DVES) visualization and findings using the image processing software SYNAPSE VINCENT(®). RESULTS: Laparoscopic and thoracoscopic/laparoscopic liver resection was successfully performed for all cases under P3DVE instruction. The mean operative times using TA, TLA, and LA approaches were 193, 185, and 190 min, respectively. Mean blood loss during TA, TLA, and LA was 179, 138, and 73 g, respectively. No patients required conversion to open surgery, and there were no deaths, although there were three cases of Clavien-Dindo grade I in TA along with three cases of grade I and one case of grade II in LA. CONCLUSIONS: TA, TLA, and LA routes performed under P3DVE instruction are feasible and safe to perform for pure laparoscopic and thoracoscopic/laparoscopic liver resection in selected patients with lesions located in the hepatic subdiaphragmatic area.

Realistic endoscopic image generation method using virtual-to-real image-domain translation.

A realistic image generation method for visualisation in endoscopic simulation systems is proposed in this study. Endoscopic diagnosis and treatment are performed in many hospitals. To reduce complications related to endoscope insertions, endoscopic simulation systems are used for training or rehearsal of endoscope insertions. However, current simulation systems generate non-realistic virtual endoscopic images. To improve the value of the simulation systems, improvement of the reality of their generated images is necessary. The authors propose a realistic image generation method for endoscopic simulation systems. Virtual endoscopic images are generated by using a volume rendering method from a CT volume of a patient. They improve the reality of the virtual endoscopic images using a virtual-to-real image-domain translation technique. The image-domain translator is implemented as a fully convolutional network (FCN). They train the FCN by minimising a cycle consistency loss function. The FCN is trained using unpaired virtual and real endoscopic images. To obtain high-quality image-domain translation results, they perform an image cleansing to the real endoscopic image set. They tested to use the shallow U-Net, U-Net, deep U-Net, and U-Net having residual units as the image-domain translator. The deep U-Net and U-Net having residual units generated quite realistic images.