👉 Phacocystectomy is a surgical procedure used to remove the phacotherma, or the lining of the uterus. This surgery is often performed during a hysterectomy to treat conditions such as endometriosis, which can cause symptoms like heavy bleeding and pain in the lower abdomen. The phacotherma is an area of the uterus where the lining grows thickened by the immune system from endometrial tissue.