A 44 y.o. Iraqi woman comes to the ED with R flank pain. She is sp a hysterectomy and L oophorectomy.

what do you see on her CT?

Hint: there appears to be a problem in the pelvis.

Our patient had two large endometriomas; one partially obstructing the R ureter. She had a previous hysterectomy because of pain caused by endometriosis. Pain and infertility are the two most important reasons women with the disease seek help.

Endometriosis is a common , estrogen-dependent, disease process where endometrial tissue is abnormally present outside the uterine cavity. The tissue can form cysts called “chocolate cysts”  because of the heme present in them.  They are commonly found in the ovaries but can be present anywhere in the body including: scar tissue bowel, lung or even cerebellum.

The best way to make the diagnosis of endometriosis is by laparoscopy.

Endometrial tissue in the pleura cause catamenial pneumothoraces.  This is defined as the onset of lung collapse less than 72 hours after menstruation.   It typically occurs in women aged 30-40, most with a history of endometriosis. CA-125 can be elevated .  In addition to pneumothorax, hemoptysis and hemothorax may also occur.  On path, endometrial implants cause “chocolate” or blood filled cysts that rupture with menstruation. Many theories exist as to why endometrial tissue is found outside the uterus but retrograde bleeding during menstruation and hematogenous spread of cells seem to predominate.

pneumothorax within 72 hrs of menstruation should prompt a consideration of endometriosis.

Endometriomas on the other hand cause hematomas like endometrial tissue anywhere, but unlike those seen in the ovaries with ovulation, they are lined with sticky endometrial stroma and the  glands contain more fibrous tissue .  They present with adhesions to surrounding tissue. A small subset of these patients develop invasive endometriosis which invades the bowel or bladder. At this point oral contraceptives or GnRH agonists are not helpful and surgery is necessary.

Our patient was seen by urology but her hydro on the R was not deemed to require a stent and she was referred to minimally invasive gyne surgery for surgery.

Peikert T, Gillespie D, Cassivi S. Catamenial pneumothorax. 2005 Mayo Clinic Proceedings . 80(5):677-80.

Meggyesy M, Friese M, Gottschalk J, Kehler U.  Case report of cerebellar endometriosis. J Neurol Surg A Cent Eur Neurosurg.  2020Jul;81(4):372-76.

Hoyle A, Puckett Y. Endometrioma June 12, 2020. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK559230/