Comparative study of continuous and pulsed CO2 laser on tissue healing and fertility outcome in tubal anastomosis.

Continuous wave (CW) CO2 laser using a power of 20 W and a spot size of 0.2 mm was used to cut the left uterine horn in 15 rats. Pulsed CO2 laser using a power of 14 W, pulse repetition rate of 400 pps, and a spot size of 0.2 mm was used to cut the left uterine horn in 16 rats. The right uterine horn was sham-operated and used as a control in each group. Microsurgical anastomosis of the cut horn was performed. The effect on fertility showed a pregnancy rate of 66.6% and 81.25% for the CW and pulsed CO2 laser, respectively. Histopathology studies of the anastomotic site revealed thinning of muscularis with fibrosis of both muscularis and subserosal layers in the CW CO2 laser-treated group. There was no thinning, disruption, or fibrosis of muscularis in pulsed laser-treated group. Adhesion score was not different in the two groups.