Vascular microanastomosis with diode laser. Control study and morphological results

Direct diode laser carotid (0.7-1.2 mm) end-to-end microanastomosis versus contro-lateral manual suture microanastomosis (CMA) were performed in 70 Wistar rats. The laser beam-wavelength 830 nm- was transmitted through a micromanipulator and provided a focused spot of 300 microns in diameter. After placement of three 10.0 Ethilon stitches for edge coaptation, the laser anastomosis was performed using laser shots (average 3) of 500 mW power, 4.5 s duration and 700 W/cm2 irradiance each. CMA was performed by six 10.0 stitches. Good vascular flow was confirmed by macroscopic controls, Doppler spectral analysis (n = 548) and digitalized angiography (n = 18) performed from day 0 to day 210. The patency rate (93%) as well as the complication rate (5/66) were similar in both series. Nevertheless light and scanning electron microscopy (n = 82) showed the morphological superiority of laser anastomosis: reendothelialization by day 3 and medial collagen restructuration by day 10 whilst after CMA, the arterial wall repair was delayed and the medial scar occupied by fibrotic tissue. The other advantages of the laser anastomosis were, shorter operating time minimizing organ ischemia (13 min versus 22 min), and slight endothelial trauma reducing thrombogenic risk. The technical advantages of diode laser were pointed out: miniaturization, no special maintenance and decreasing price of diodes.