Omental Endometriosis
A 37-year-old woman presented to the outpatient gynecology clinic with crampy lower abdominal pain that occurred during menstruation. Her medical history was notable for ovarian endometriosis, which had been treated laparoscopically 5 years earlier. Magnetic resonance imaging revealed a cystic mass, measuring 4.1 cm by 4.1 cm by 4.1 cm, in the lower abdomen that had a high signal intensity on T1-weighted imaging (Panel A). A laparoscopy was performed, and the mass was found to be of omental origin (Panel B; loops of bowel are also visible). The uterus and ovaries appeared normal. Pathological examination of the resected mass showed findings consistent with endometriosis. Endometriosis of the omentum is a form of extrapelvic endometriosis. On follow-up 1 month later, the patient reported no further abdominal pain. She became pregnant 15 months after the laparoscopy.