Vessel-wall recovery after diode laser-assisted microvascular anastomosis: clinical and histologic analysis on long-term follow-up.

The authors recently reported an experimental study on diode laser-assisted microvascular anastomosis (LAMA) in the femoral arteries and veins of rats. Good success rates and very promising histologic results obtained in this preliminary phase suggested an extension of the investigation with a larger number of rats and for longer follow-up periods. In the present work, they describe an experimental study with two main goals: 1) improvements of the laser-assisted surgical procedure for reduction in the number of permanent stay sutures, with minimization of bleeding at the end of the intervention, compared with conventional microvascular sutured anastomosis (CMSA); and 2) providing more information on the repair mechanism(s) induced by laser treatment, obtained from clinical and histologic analyses extended up to 3 months of follow-up. In a total of 64 Wistar rats, 46 arterial and 22 venous LAMAs were performed, and 15 arterial and 11 venous CMSAs. The recorded success rates of LAMA in both arteries and veins were fairly high (67/68 at the time of surgery, and 54/55 in the follow-up), and substantially comparable with those of CMSA. Clear evidence of a superior healing process in the LAMAs was provided by histologic examinations. In particular, specific stains and immunohistochemistry analysis indicated that laser irradiation can induce wide proliferation of smooth muscle cells and negligible scar tissue which, together with diminished foreign-body reaction consequent to the reduction of suture material, result in a better restoration of vessel structures.