Endometriosis that involves the nerves: how Radiologists can help

Important imaging findings related to Endometriosis involving the pelvic nerves

Key Points

Highlights:

• Endometriosis involving the pelvic nerves is a rare but important finding that should be assessed on pelvic MRI in patients who have symptoms suspicious for endometriosis.

Importance:

• Imaging of endometriosis requires knowledge of general abdominal anatomy and imaging features of the diverse pathologic manifestations of endometriosis.

What's done here:

• Authors aim to provide an overview of endometriosis-associated anatomical concepts and the intrapelvic nerves that are seen to be involved in patients with endometriosis-driven neuropathy.

Key results:

• Endometriosis-associated neuropathy is a rare form of endometriosis that should be diagnosed as soon as possible, preferably with pelvic MRI read by an experienced abdominal radiologist.
• Similar to the findings of other, larger studies, the authors found that the sacral plexus and sciatic nerves were the most commonly involved in patients with endometriosis who demonstrated neurologic symptoms.
• The most common radiologic findings include fibrous tissue with low signal intensity on MRI or the presence of an endometrioma characterized by low signal intensity.

Limitations:  

• This study is a review of pertinent radiologic findings of endometriosis nerve involvement and reports findings of 7 patients with symptoms and radiologic findings consistent with endometriosis.

Lay Summary

Endometriosis is a disease with variable clinical symptoms.

While rare, nerve involvement by endometriosis may cause neurologic symptoms such as pelvic pain, muscle weakness, bowel and bladder incontinence, and paraplegia depending on the specific nerve involved. Thus, abdominal radiologists should assess pelvic nerve anatomy especially on pelvic MRI and the possible patterns of presentation in patients with nerve-involving endometriosis in order to prevent permanent nerve damage. Therefore, early diagnosis of this rare disease manifestation cannot be overlooked.

In this pictorial essay entitled 'What abdominal radiologists should know about extragenital endometriosis-associated neuropathy, published in a journal named "Abdominal Radiology", authors aim to review the pertinent pelvic nerve anatomy that may be associated with rare endometriosis-associated neuropathy. The lumbosacral plexus is one such network of the nerve that may be involved. They supply the lower extremity and pelvic wall through offshoots such as the femoral, obturator, and ilioinguinal nerves. Seven cases are reported in this article that display the variability of endometriosis nerve involvement. All seven patients suffered cyclic pelvic pain, while four had a motor impairment and mentioned sensorial symptoms. One patient had fecal and urinary incontinence. Authors noted either an infiltrative type of endometriosis or those with features of endometrioma. The most commonly involved nerve was the sciatic nerve.

Extragenital endometriosis with neural involvement is uncommon and may manifest with neurological symptoms, including pain, muscle weakness, bowel and bladder incontinence, and paraplegia. The longer the lesions are untreated, cyclic inflammation from hemorrhage causes increasing fibrosis of associated nerves and eventually may lead to permanent neural damage.

Pelvic MRI performed in patients before undergoing definitive treatment is extremely helpful for appropriate surgical planning.

Research Source: https://www.ncbi.nlm.nih.gov/pubmed/30539250