Comparison of laser-assisted and conventionally sutured microvascular anastomoses by bursting pressure: a reanalysis and further studies.

Methods of testing the strength of microvascular anastomoses are reviewed historically, in the light of recent applications to laser-assisted microvascular anastomosis techniques. The results of two experiments using hydrostatic distension to bursting point to determine the strengths of laser-assisted and conventionally sutured anastomoses of rat arteries and veins are presented. Considerable variation of the bursting pressures was found at any given time after anastomosis, and by the third postoperative day, the sutured vessels showed a significant fall in strength to their weakest level, with not as great a fall in the laser group. The sutured vessels were stronger than were the laser-anastomosed vessels, except at 3 days and after 6 weeks, when there were no significant differences between the two types of anastomosis. Aneurysmal vessels did not always burst at lower pressures than did nonaneurysmal vessels of comparable age.