[Study on the electrothermal tissue effects during transcervical resection of endometrium]

To investigate the tissue electrothermal effects and to seek the appropriate setting of operative wattage during transcervical resection of endometrium (TCRE).

The power setting were 60 W, 80 W, 100 W for cutting and 30 W, 60 W, 80 W, 100 W for coagulation when performing endometrial resection in vitro or in vivo with operating time 3-5 seconds or 6-8 seconds respectively. After operation the uterine specimens were stained by hemaloxylin-eosin, and respiratory enzyme dehydronicotinamide adenine dinucleotide phosphate diaphorase methods for evaluating the tissue damage.

(1) The depth of endometrial damage under cutting was considerably less severe than those under coagulation with the same power setting. (2) When the power of cutting and coagulation were 80 W, 100 W and 30 W, 60 W respectively and operating time prolonged more than 5 seconds, the thermal damage covered endometrium and 2-3 mm of myometrium in depth. (3) At such wattage and operating time the deepest destruction was only 16.27% of uterine wall.

(1) There is significant difference in the depth of thermal damage between cutting and coagulation during hysteros copic surgery. (2) The appropriate power setting should be 80-100 W for cutting and 30-60 W for coagulation.