Contribution of ultrasound in the assessment of patients with suspect idiopathic pudendal nerve disease

Abstract

Objective: To assess if Ultrasound (US) is contributive in patients suspected of having idiopathic pudendal neuralgia.

Methods: Between July 2012 and April 2013, 10 consecutive female patients with suspected idiopathic pudendal neuralgia (mean age: 47±14 years; mean BMI: 24±3) were included. Two radiologists blinded to the clinical and neurophysiological data performed pudendal nerve evaluation with broadband linear array transducers (12-7 MHZ, and 17-5 MHZ). MRI was added to confirm US data. A third independent clinician, who did not perform electrodiagnosis and US, reviewed the data and scored US as "contributive" or "non-contributive": if US confirmed the clinical and neurophysiological diagnosis or if US findings were not useful.

Results: Ultrasound identified alterations to the pudendal nerve in 7/10 of cases (70%). In seven cases US revealed the presence of a diffusely or focally enlarged pudendal nerve confirmed by MRI. In these cases neurophysiological findings were suspicious for pudendal neuralgia in 5/7 cases, whereas in 2/7 cases they were inconclusive.

Conclusion: High-resolution ultrasound (US) may demonstrate alterations to the pudendal nerve in patients with pudendal neuralgia.

Significance: US is useful in patients with suspected idiopathic pudendal nerve disease.

Keywords: Anatomy; Entrapment; Magnetic resonance imaging; Pathology; Perineal nerves; Pudendal nerve; Ultrasound.