Histologic and scanning electron microscopic study for portal vein sutureless anastomosis by magnetic compression anastomosis in canines / 中华肝胆外科杂志

ABSTRACT

Objective:To compare the histological differences between magnetic anastomosis and traditional suture in canine portal vein (PV) .Methods:Eighteen healthy Chinese garden dogs, either gender, 8-12 months and weighing 13.5-18.9 kg, were randomly divided into magnetic compressive anastomats (MCA) group ( n=9) and hand-sewing (HS) group ( n=9) for PV reconstruction. The time of PV anastomosis was compared between the two groups. HE and Masson staining were performed immediately and at 4, 8, 12 and 24 weeks after operation. The ultrastructure of the anastomosis was observed using scanning and transmission electron microscopy. Results:All dogs survived. The PV anastomosis time was significantly shorter in MCA group (3.58±2.75) min than that HS group (12.89±3.12) min, P<0.01. In MCA group, the vascular wall of anastomotic stoma was well aligned immediately after operation, and the shrinkage was obvious in HS group by gross eyes. At 24 weeks, electron microscope scanning showed the re-endothelialization was smooth and endothelial cells arranged regularly at the anastomotic site of the MCA group, whereas different-sized and irregularly aligned endothelial cells and large collagenous fibers arranged in disorder were present at the HS anastomotic stoma. Representative HE and Masson staining confirmed that the magnetic device was associated with decreased infiltration of inflammatory cells and deposition of fibrotic collagen at 24 weeks explanted anastomotic stomas compared with the HS group. Conclusions:Compared with the HS, MCA produced shorter anastomosis time, smooth anastomotic intima, light fibrous tissue hyperplasia, no foreign body residue, mild inflammatory reaction and reliable technique for canines PV anastomosis.