OBJECTIVE: Our purpose was to compare the thermal intraperitoneal injury in lesions resulting from a monopolar electrosurgical loop electrode designed for laparoscopic surgery with similar lesions fashioned by carbon dioxide laser vaporization.

STUDY DESIGN: A randomized, observer-blinded comparison was made of histopathologically measured thermal injury in rat uterine horns. The primary outcome measure was the depth of necrotic debris and coagulative necrosis in the lesions created by the two methods.

RESULTS: The depth of coagulative necrois was similar in the laser vaporization (0.118 ± 0.028 mm) and the loop excision groups (0.165 ± 0.167 mm). However, the average amount of necrotic debris was greater in the lasered lesions (0.053 ± 0.019 mm) compared with those made with the loop electorde (0.013 ± 0.011 mm).

CONCLUSIONS: The depth of coagulative necrosis in rat uterine lesions fashioned with a loop electrode is similar to that of lesions created by carbon dioxide vaporization at power densities comparable with those usually achieved at laparoscopic surgery. There is a greater amount of necrotic debris in the lasered lesions. This suggest that electrosurgical loops designed for laparoscopic surgery may have promise for the cost-effective excision of intraperitoneal tissue.