title: Magnamosis: magnetic compression anastomosis with comparison to suture and staple techniques.
abstract: OBJECTIVE
  An ideal anastomosis between hollow viscera should be easily performed, strong, and operator independent. We hypothesized that transluminal attraction between magnets in the intestine could be harnessed to create an intestinal compression anastomosis (magnamosis) with these characteristics. We further hypothesized that variation of attraction force and geometry of compression would affect the quality of the intestinal anastomosis.
  
  
  METHODS
  We designed a self-orienting device composed of 2 neodymium-iron-boron magnets affixed to polytetrafluoroethylene moldings. Two topologies were evaluated: one designed with 'uniform' compression and the other with 'gradient' compression. Sixteen young adult pigs (Sus scrofa) underwent laparotomy with creation of a magnetic side-to-side anastomosis: 8 with the uniform device and 8 with the gradient device. Each also had a stapled anastomosis, and 5 had an additional hand-sutured anastomosis. Animals were euthanized at 1, 2, and 3 weeks after operation, then anastomoses were compared on the basis of gross appearance, histology, functional radiography, and mechanical integrity.
  
  
  RESULTS
  All magnetic devices formed patent anastomoses without leak. One stapled anastomosis resulted in a contained leak. Mechanical integrity of magnetic anastomoses was not statistically significantly different from staple or suture counterparts, and there was a trend toward greater strength with magnetic anastomoses. Comparison between device types revealed the gradient device trended toward greater strength and earlier patency (67% vs 33% at 1 week). There was no evidence of stenosis, and histologic examination demonstrated tissue remodeling with mucosal and serosal apposition across the magnamoses.
  
  
  CONCLUSIONS
  The magnetic compression anastomosis (magnamosis) device is a safe and effective means of sutureless full-thickness intestinal anastomosis with serosal apposition in a pig model. Gradient compression is superior to uniform compression. This technique is compatible with endoscopic and natural orifice approaches.
authors.affiliation: Department of Surgery, University of California San Francisco, CA 94143-0570, USA.
authors.forename: Ramin
authors.initials: R
authors.lastname: Jamshidi
authors.forename: Jacob T
authors.initials: JT
authors.lastname: Stephenson
authors.forename: Jared G
authors.initials: JG
authors.lastname: Clay
authors.forename: Kullada O
authors.initials: KO
authors.lastname: Pichakron
authors.forename: Michael R
authors.initials: MR
authors.lastname: Harrison
mesh_terms: D000714:Anastomosis, Surgical / Q000295:instrumentation* / Q000379:methods*; D000818:Animals; D004867:Equipment Design; D007422:Intestines / Q000601:surgery*; D008280:Magnetics; D017792:Surgical Stapling; D013536:Suture Techniques; D013552:Swine