A computer-controlled, continuously circulating, hot irrigating system for endometrial ablation

This study evaluated the efficacy of a computer-controlled thermal catheter system to ablate the endometrium by use of 5 to 15 ml of hot saline solution.

Five in vivo sheep uteri and 32 freshly excised human uteri were studied by inserting a self-contained heater catheter equipped with thermocouples and circulating hot saline solution for 15 minutes within the uteri at various temperature settings ranging from 60 degrees C to 80 degrees C. The uteri were grossly examined and microscopically evaluated by hematoxylin and eosin and reduced nicotinamide adenine dinucleotide-diaphorase stains for degree of acute destruction, depth of thermal injury, and predicted viability.

All 80 degrees C sheep treatments resulted in complete loss of viability at mucosal, submucosal, and myometrial levels. In human uteri temperatures > or = 80 degrees C produced grossly recognizable thermal damage to the endometrium. Full-thickness irreversible damage was seen in the endometrium. Loss of viability was also demonstrated 1 to 3 mm deep in the superficial myometrium. Intrauterine pressure was demonstrated to range from 20 to 40 mm Hg, with a mean of 26 mm Hg. No leakage of fluid from the oviducts was observed.

The data presented here demonstrate that a simple technique coupled with a sophisticated monitoring control system could successfully ablate the endometrium without the vagaries associated with individual operator skill levels.