An Original Endoluminal Magnetic Anastomotic Device Allowing Pure NOTES Transgastric and Transrectal Sigmoidectomy in a Porcine Model: Proof of Concept

IRCAD/EITS Institute, University Hospital of Strasbourg, Strasbourg, France.
Surgical Innovation (Impact Factor: 1.34). 12/2011; 19(2):109-16. DOI: 10.1177/1553350611429029
Source: PubMed

ABSTRACT While experimental natural orifice transluminal endoscopic surgery (NOTES) sigmoid colectomies have been reported, pure NOTES anastomoses are restricted by the limited reach of commercially available circular staplers. MAGNAMOSIS is a set of self-orienting magnetic rings that can be delivered endoluminally throughout the colon to generate a compression anastomosis. Aim. To assess the feasibility of a pure NOTES transrectal (TR) and transgastric (TG) approach to perform any segmental colectomy.
One pig (50 kg) underwent the experimental procedure as follows: (a) creation of the TG access to the peritoneal cavity, (b) precise transluminal placement of the proximal MAGNAMOSIS ring, (c) creation of the TR access with the TEO and transrectal dissection of the sigmoid mesentery, (d) resection of the surgical specimen, (e) transrectal extraction of the specimen, (f) delivery and mating of the distal MAGNAMOSIS ring, and (g) closure of the TG and TR viscerotomies. The animal survived for 14 days at which time burst pressure and histology were performed.
A pure NOTES TR and TG segmental colectomy was performed in 139 minutes. The postoperative course was uneventful. The animal had a formed bowel movement including the magnetic rings on postoperative day 5. Endoscopic examination at postoperative day 14 revealed a patent anastomosis. Necropsy revealed no abscess or signs of peritonitis. Burst pressure was >198 mm Hg. The histology showed a sealed anastomosis with mild inflammation.
MAGNAMOSIS enabled a totally NOTES partial colectomy with combined TG and TR access. The flexible delivery options and low cost of manufacturing could make MAGNAMOSIS an attractive alternative to circular staplers.

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