Comparison of myointimal hyperplasia in laser-assisted and suture anastomosed arteries. A preliminary report

Use of the milliwatt CO2 laser to perform microvascular anastomoses is associated with characteristic histologic changes, including intimal hyperplasia and medial necrosis. The extent of myointimal proliferation after both suture and laser-assisted vascular anastomosis was assessed in the rat femoral artery model. At 2 weeks the average intimal height of the laser-anastomosed vessels was 11.7 +/- 2.2 microns (mean +/- standard error of the mean) vs. 21.3 +/- 3.2 microns for sutured arteries (p less than 0.05). By 6 weeks the groups were equivalent (laser, 25.6 +/- 4.6 microns; suture, 17.3 +/- 1.2 microns; p, not significant). The medial changes associated with the laser-assisted method appear to inhibit the proliferative response at 2 weeks but are reversed by 6 weeks.