Magnets and self-retractable wire for endoscopic septotomies: From concept to first-in-human use.

Background and study aims: A medical device that allows simple and safe performance of an endoscopic septotomy could have several applications in the gastrointestinal (GI) tract. We developed such a device by combining two magnets and a self-retractable wire to perform a progressive septotomy by compression of the tissues. We describe here the concept, preclinical studies, and first clinical use of the device in symptomatic epiphrenic esophageal diverticulum (EED). Materials and methods: The MAGUS was designed based on previous knowledge of compression anastomosis and current unmet needs. After initial design, the feasibility of the technique was tested on artificial septa in pigs. A clinical trial was then initiated to assess the feasibility and safety of the technique. Results: Animal studies showed that the MAGUS can perform a complete septotomy at various levels of the GI tract. In two patients with symptomatic EED, uneventful complete septotomy was observed within 28 and 39 days after the endoscopic procedure. Conclusions: This new system provides a way to perform endoluminal septotomy in a single procedure. It appears to be effective and safe for managing symptomatic EED. Further clinical applications where this type of remodeling of the GI tract could be beneficial are under investigation.

Design of a force-measuring setup for colorectal compression anastomosis and first ex-vivo results

Purpose The introduction of novel endoscopic instruments is essential to reduce trauma in visceral surgery. However, endoscopic device development is hampered by challenges in respecting the dimensional restrictions, due to the narrow access route, and by achieving adequate force transmission. As the overall goal of our research is the development of a patient adaptable, endoscopic anastomosis manipulator, biomechanical and size-related characterization of gastrointestinal organs are needed to determine technical requirements and thresholds to define functional design and load-compatible dimensioning of devices. Methods We built an experimental setup to measure colon tissue compression piercing forces. We tested 54 parameter sets, including variations of three tissue fixation configurations, three piercing body configurations (four, eight, twelve spikes) and insertion trajectories of constant velocities (5 mms−1, 10 mms−1,15 mms−1) and constant accelerations (5 mms−2, 10 mms−2, 15 mms−2) each in 5 samples. Furthermore, anatomical parameters (lumen diameter, tissue thickness) were recorded. Results There was no statistically significant difference in insertion forces neither between the trajectory groups, nor for variation of tissue fixation configurations. However, we observed a statistically significant increase in insertion forces for increasing number of spikes. The maximum mean peak forces for four, eight and twelve spikes were 6.4 ± 1.5 N, 13.6 ± 1.4 N and 21.7 ± 5.8 N, respectively. The 5th percentile of specimen lumen diameters and pierced tissue thickness were 24.1 mm and 2.8 mm, and the 95th percentiles 40.1 mm and 4.8 mm, respectively. Conclusion The setup enabled reliable biomechanical characterization of colon material, on the base of which design specifications for an endoscopic anastomosis device were derived. The axial implant closure unit must enable axial force transmission of at least 28 N (22 ± 6 N). Implant and applicator diameters must cover a range between 24 and 40 mm, and the implant gap, compressing anastomosed tissue, between 2 and 5 mm.