MRI can accurately detect and localise "deep" endometriosis

Endometriosis is a chronic and sometimes painful disease which is one of the most common health problems affecting women; endometrium is found in atopic positions outside the uterus. It can be found attached to other organs such as the ovaries, fallopian tubes, bowels and bladder. Symptoms include chronic pelvic pain, lower back pain, painful sexual intercourse, painful menstrual cramps, fatigue and infertility.

There are two types of endometriosis: superficial and sub-peritoneal (deep). Superficial endometriosis can be treated with laparoscopy. Deep endometriosis infiltrates areas of the cervix, vagina and/or the colon, and, less frequently, the bladder and ureter and sometimes requires complete surgical excision of the lesions

It is important that the diagnosis and staging of the disease distinguish between the two types in order to guide the surgeon to schedule the most appropriate procedure.

Radiologists in Brussels led by Dr Nathalie Hottat assessed the usefulness of magnetic resonance imaging (MRI) at 3T in the diagnosis and accurate localisation of deep endometriosis.

"Pelvic MRI at 3 Tesla is a non-invasive technique that allows a complete examination of the pelvis," said the study's lead author, Nathalie Hottat, M.D., from the Department of Radiology at Erasme Hospital and the Université Libre de Bruxelles in Brussels, Belgium. "It accurately depicts all locations of deep endometriosis."  The researchers studied 41 women, age 20 – 46, with suspected endometriosis. MRI was performed prior to surgery. MRI accurately diagnosed 26 of 27 cases of deep endometriosis. In addition, MR images accurately depicted specific locations of deep endometrial lesions. The 3-T MRI results also demonstrated a high negative predictive value of 93.3 percent meaning that MRI findings accurately ruled out deep endometriosis in patients with superficial endometriosis, allowing the surgeon to perform the less invasive laparoscopic procedure.

Colon wall involvement was present in 32 percent of patients with deep endometriosis and MRI was effective at distinguishing different layers of the affected colon wall and accurately depicted the degree of colon wall invasion.