Hand Sewn Anastomosis Skill Acquisition and In Vivo Transfer Using 3D-Printed Small Bowel Simulator.

INTRODUCTION: General surgery residents need to master the hand-sewn bowel anastomosis (HSBA) technique. However, practice opportunities outside of the operating room are rare, and commercial simulators are often costly. The objective of this study is to assess the efficacy of a new, affordable silicone small bowel simulator, made with a three-dimensional (3D) printed mold, as a training tool to learn this technique. METHODS: This was a single-blinded pilot randomized controlled trial comparing two groups of eight junior surgical residents. All participants completed a pretest using an inexpensive, custom developed 3D-printed simulator. Next, participants randomized to the experimental group practiced the HSBA skill at home (eight sessions), while those randomized to the control group did not receive any hands-on practice opportunities. A posttest was done using the same simulator as for the pretest and practice sessions, and the retention-transfer test was performed on an anesthetized porcine model. Pretests, posttests and retention-transfer tests were filmed and graded by a blinded evaluator using assessments of technical skills, quality of final product, and tests of procedural knowledge. RESULTS: The experimental group significantly improved after practicing with the model (P = 0.01), while an equivalent improvement was not noted in the control group (P = 0.07). Moreover, the experimental group's performance remained stable between the posttest and the retention-transfer test (P = 0.95). CONCLUSIONS: Our 3D-printed simulator is an affordable and efficacious tool to teach residents the HSBA technique. It allows development of surgical skills that are transferable to an in vivo model.

Quantification and 3D Localization of Magnetically Navigated Superparamagnetic Particles Using MRI in Phantom and Swine Chemoembolization Models.

OBJECTIVE: Superparamagnetic nanoparticles (SPIONs) can be combined with tumor chemoembolization agents to form magnetic drug-eluting beads (MDEBs), which are navigated magnetically in the MRI scanner through the vascular system. We aim to develop a method to accurately quantify and localize these particles and to validate the method in phantoms and swine models. METHODS: MDEBs were made of Fe3O4 SPIONs. After injected known numbers of MDEBs, susceptibility artifacts in three-dimensional (3D) volumetric interpolated breath-hold examination (VIBE) sequences were acquired in glass and Polyvinyl alcohol (PVA) phantoms, and two living swine. Image processing of VIBE images provided the volume relationship between MDEBs and their artifact at different VIBE acquisitions and post-processing parameters. Simulated hepatic-artery embolization was performed in vivo with an MRI-conditional magnetic-injection system, using the volume relationship to locate and quantify MDEB distribution. RESULTS: Individual MDEBs were spatially identified, and their artifacts quantified, showing no correlation with magnetic-field orientation or sequence bandwidth, but exhibiting a relationship with echo time and providing a linear volume relationship. Two MDEB aggregates were magnetically steered into desired liver regions while the other 19 had no steering, and 25 aggregates were injected into another swine without steering. The MDEBs were spatially identified and the volume relationship showed accuracy in assessing the number of the MDEBs, with small errors (≤ 8.8%). CONCLUSION AND SIGNIFICANCE: MDEBs were able to be steered into desired body regions and then localized using 3D VIBE sequences. The resulting volume relationship was linear, robust, and allowed for quantitative analysis of the MDEB distribution.

Development and Learner-Based Assessment of a Novel, Customized, 3D Printed Small Bowel Simulator for Hand-Sewn Anastomosis Training.

Hand-sewn bowel anastomosis (HSBA) is an essential skill for surgical residents to learn, as it is used in numerous surgical procedures. However, the opportunities to practice this skill before attempting it on patients are limited. Practice on simulators can help improve this technique, but there is a paucity of realistic, cost-efficient simulators for the acquisition of HSBA skills. This technical report describes the development of our simulator that consists of a small bowel manufactured from silicone and a 3D-printed clamp system to hold the bowel in place. Our simulator was co-designed by a clinical team of surgeons and then assessed for perceived acceptability and effectiveness by 16 junior residents in various surgical specialties at our faculty. A majority of the learners rated our simulator to be a good or very good learning tool for HSBA, although they suggested some minor improvements. Overall, our silicone small bowel model appears to be an effective and inexpensive way to acquire this surgical skill.