Other - Novel NOTES Techniques for Retraction and Dissection: Harnessing the Power of Magnets and Gravity
Comments: As the line separating GI endoscopy and abdominal surgery begins to blur, old principles of tissue manipulation become particularly salient. Significant examples include adequate exposure, understanding tissue planes, triangulation of instruments, and robust traction and counter-traction. We propose novel techniques for exposure and dissection that may facilitate future NOTES endeavors.
First, good positioning is key to good exposure. Here, the prone position, which is infrequently used in laparoscopy, provides an exceptional view of retroperitoneal structures. As the abdominal viscera falls forward, the kidneys and distal pancreas, for example, can be directly accessed. Furthermore, both sides can be accessed with relative ease.In the pelvis, the uterus, fallopian tubes, and ovaries are also well-visualized, and even the cul-de-sac can be made out.
In addition to positioning, we have used magnets to lend an invisible hand. The following is transcolonic mesh implantation for ventral hernia repair. The magnet positioned and eventually stabilized the mesh by engaging ferromagnetic clips affixed to the corners of the mesh. Transfascial T-tags were used to tack down the corners. Three pigs were survived two weeks, and they all did well.
Externally, powerful neodymium magnets were attached to a multi-jointed, lock-able support arm that clamped to the edge of an operating table. The force-distance relationship of our system were determined using a digital tensiometer. Using this data, we constructed a stronger magnetic system capable of lifting visceral organs. To enhance magnetic attraction, small neodymium disc magnets were attached by suture to Resolution clips and deployed on the edge of an organ of interest-in this case, the inferior edge of a hepatic lobe-to fully expose the gallbladder fossa. Transcolonic cholecystectomy with the use of magnets was repeated in 2 additional non-survival animals. The procedure time was shortened from a historical mean of 68 minutes to only 49 minutes. Liver retraction was both robust and sustained, allowing for vigorous counter-traction, as seen here.
In commencing dissection of the gallbladder, we found the technique of hydro-dissection quite helpful in separating tissue planes. Sterile saline was injected by a Carr-Locke sclerotherapy injection needle. Connective tissue was readily exposed, creating a virtual road-map for the application of electrocautery. Also helpful was the use of the prototype R-scope from Olympus which had elevators for each instrument port oriented perpendicularly. This allowed one instrument to travel in the vertical plane, and the other instrument in the horizontal plane. Dissection proceeded from the fundus to the neck, using a combination of blunt dissection, as seen here, and electrocautery, as stated before. Following gallbladder resection, and electrocoagulating small bleeders in the gallbladder fossa, the magnetic clips were easily removed using biopsy forceps.
Transcolonic distal pancreatectomy combined many of the themes mentioned before. After the animal was positioned prone, air dissection, as opposed to water this time, was used to expose tissue planes. The distal portion was elevated by the R-scope to facilitate dissection of the base. The entire dissection took less than ten minutes. Next, a computer-controlled rigid linear stapler from Power Medical Interventions was introduced transvaginally and into the abdominal cavity under endoscopic visualization. At the lower left is a prototype flexible iteration which should see NOTES application very soon. With its jaws open, the stapler engaged the distal pancreas flush against its base. The stapler was successfully fired and disengaged. The resected specimen was retrieved using a Roth net. Upon visual inspection, there was no bleeding or gross leakage of pancreatic fluid from the staple line. This procedure was performed in three non-survival pigs to demonstrate technical feasibility, followed by two survival pigs that both did well.
This presentation has aimed to report novel NOTES techniques for retraction and dissection. We thank you for your attention.
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Marvin Ryou, MD Brigham and Women's Hospital Reina D. Pai, MD Brigham and Women's Hospital Derek G. Fong, MD Brigham and Women's Hospital David W. Rattner, M.D. Chief, Division of General and Gastrointestinal Surgery Massachusetts General Hospital Christopher C. Thompson, M.D. Director of Developmental Endoscopy Brigham and Women's Hospital |
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Citation: Ryou, M. & Pai, RD & Fong, DG & Rattner, DW & Thompson, CC (May 21 2007). Other - Novel NOTES Techniques for Retraction and Dissection: Harnessing the Power of Magnets and Gravity. The DAVE Project. Retrieved Sep, 8, 2010, from http://daveproject.org/viewfilms.cfm?film_id=609 Times viewed since Feb 2006: 6496 |
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