Dose-dependent inactivation of extracellular human immunodeficiency virus by miramistin

BACKGROUND: There is a need for an atraumatic, fast, reliable, inexpensive, reversible-on-demand method for female sterilization which is also free from side-effects. The use of an Nd:YAG laser for occlusion of human fallopian tubes in vitro was assessed for achieving these aims. METHODS: An in vitro study was performed on coagulation of fallopian tube tissue using continuous wave Nd:YAG laser. Posthysterectomy human uteri were exposed to laser radiation either directly through an optical fibre or through a sapphire contact probe at the ostia at different laser powers and inter-action times. RESULTS: Laser-induced tissue coagulation plugged the ostia in a clean, controlled and predictable manner. Microscopic examination of the coagulated tissue showed about 50 microns wide blind holes without any continuous channel; thus eliminating the possibility of passage of sperms through such a plug. The depth of coagulation along the lumen of the fallopian tubes increased linearly with the interaction time of the laser beam at a constant power, either by direct irradiation or through a contact probe. The maximum depth of coagulation was found to be about 3 mm in case of direct irradiation at a laser power of about 6.5 W and interaction time of 50 seconds. Beyond these values, charring occurred at the surface of the tissue. CONCLUSION: Nd:YAG laser might be a suitable means for female sterilization. Further studies in experimental and clinical settings would be required to confirm its utility.