What abdominal radiologists should know about extragenital endometriosis-associated neuropathy

The aim of this study is to provide an overview of endometriosis-associated neuropathy and to review main anatomical concepts of intrapelvic peripheral nerves.

In this pictorial essay, we review the anatomy of pelvic nerves and imaging features of endometriosis-associated neuropathy. We also evaluate clinical findings, imaging features, and outcome of seven patients with endometriosis-associated neuropathy.

Nerve involvement by endometriosis is rare and may manifest with neurological symptoms, including pain, muscle weakness, bowel and bladder incontinence, and paraplegia. The neural involvement may be isolated or caused by a direct extension of a deep infiltrating endometriosis of the pelvic structure. Magnetic resonance imaging (MRI) is a reliable imaging modality for detecting neural involvement of endometriosis. On MRI, the main imaging features are retractile fibrous tissue and endometriomas. The signal intensity of the endometriotic tissue may vary depending on the age of the hemorrhage and the proportion of endometrial cells and stroma. Early diagnosis and treatment may avoid permanent neural damage.

Considering that patients with endometriosis usually undergo pelvic MRI, which is generally reported by a non-musculoskeletal-trained radiologist, abdominal radiologists need to be familiar with the pelvic nerve anatomy and the possible patterns of presentation of neural endometriosis. Early diagnosis may obviate permanent nerve damage and MRI is a reliable tool for the diagnosis.