Computed tomography-guided pudendal nerve block. A new diagnostic approach to long-term anoperineal pain: a report of two cases.

OBJECTIVE To show the value of computed tomography (CT) in selectively blocking the pudendal nerve in patients with long-term anogenital pain of uncertain etiology. We report a technique to selectively block the pudendal nerve using CT guidance in 2 patients with long-term anogenital pain. CASE REPORT In 1 patient, a competitive cyclist, the diagnosis of pudendal neuralgia was substantiated by blocking the nerve under CT. The procedure relieved the pain for approximately 24 hours. In the other patient, pudendal nerve block produced perineal analgesia but no pain relief. Superior hypogastric plexus block relieved the pain significantly for about 4 weeks on 2 separate occasions, suggesting sympathetically maintained pain. CONCLUSION The use of CT to guide the procedure allowed precision in performing the procedure and in making a differential diagnosis.