RESUMEN
OBJECTIVE: To describe effects of non-ablative erbium-doped:yttrium-aluminium-garnet (Er:YAG) laser on vaginal atrophy induced by iatrogenic menopause in the ewe. DESIGN: Animal experimental, randomised, sham and estrogen-treatment controlled study with blinding for primary outcome. SETTING: KU Leuven, Belgium. SAMPLE: Twenty-four ewes. METHODS: Menopause was surgically induced, after which the ewes were randomised to three groups receiving vaginal Er:YAG laser application three times, with a 1-month interval; three sham manipulations with a 1-month interval; or estrogen replacement and sham manipulations. At given intervals, ewes were clinically examined and vaginal wall biopsies were taken. Vaginal compliance was determined by passive biomechanical testing from explants taken at autopsy. MAIN OUTCOME MEASURES: Vaginal epithelial thickness (primary), composition of the lamina propria (collagen, elastin, glycogen and vessel content), vaginal compliance, clinical signs. RESULTS: Animals exposed to Er:YAG laser application and sham manipulation, but not to estrogens, displayed a significant and comparable increase in vaginal epithelial thickness between baseline and 7 days after the third application (69% and 67%, respectively, both P < 0.0008). In laser-treated ewes, temporary vaginal discharge and limited thermal injury were observed. Estrogen-substituted ewes displayed a more prominent increase in epithelial thickness (202%; P < 0.0001) and higher vaginal compliance (P < 0.05). None of the interventions induced changes in the lamina propria. CONCLUSIONS: Vaginal Er:YAG laser has comparable effect to sham manipulation in menopausal ewes. TWEETABLE ABSTRACT: Vaginal Er:YAG laser has comparable effect to sham manipulation in menopausal ewes #LASER #GSM #RCT.