Endometriosis can be treated at the time of diagnosis. Endometriosis is diagnosed using a surgical procedure called laparoscopy. Endometrial lesions (implants of endometrial tissue outside of the endometrium) can be cut away (excised) or burned away using a high-energy heat source, such as a laser (ablated). Treatment with laparoscopy is more difficult with advanced disease that involves large areas of the rectum or larger lesions.