Case report: peri-anal episiotomy scar endometrioma imaged by CT and sector endoluminal ultrasound

Endometriosis is a common clinical entity, and is found in approximately 15% of menstruating females. An endometrioma is somewhat less common, and is defined as functioning endometrial tissue outside the uterus. Endometriomas have been reported in a variety of different locations, including the rectus abdominis muscle following Caesarean section, skin and tissues adjacent to surgical scars, and even abdominal wall endometrial implants at the site of needle passage for amniocentesis. We present a case of a solitary endometrioma located in the peri-anal region beneath the site of an episiotomy scar. Sector endoluminal ultrasound was utilized in imaging this thick-walled, cystic mass. Episiotomy scar endometriomas have thus far only been reported in the surgical literature, without reference to radiologic imaging. Our case is illustrated with CT and sector endoluminal ultrasonography.