Intraneural Venous Malformation of the Ulnar Nerve

Abstract

Background Intraneural venous malformations affecting peripheral nerves particularly the ulnar nerve is exceedingly rare and may present as compressive neuropathies. Proper clinical evaluation, diagnostic imaging and histopathology play key roles, and microsurgical resection is mainstay of treatment. Case presentation A 20-year-old right-hand dominant female presented with right forearm cramps and intermittent numbness radiating to the hand for 3 months duration. 3 years back she has undergone surgical exploration of same region following imaging studies due to similar symptoms suspecting a vascular lesion . Previous surgical exploration has identified a clinically suspected venous malformation within and deep to the flexor tendons, for which debulking and decompression were performed and histology was confirmed as an arteriovenous malformation. After a three-year symptom free interval, similar but worsening symptoms gradually recurred  .Ultrasound scan with doppler followed by MRI showed lesion recurrence of venous malformation abutting the ulnar neurovascular bundle. Re-exploration revealed an extensive intraneural venous malformation involving the ulnar nerve. Microsurgical debulking and decompression were performed, with complete excision confirmed on histology. The patient recovered well, with improved sensation and normal hand function. Conclusion Intraneural venous malformations of the ulnar nerve, though rare, should be considered in the differential diagnosis of atypical neuropathic symptoms. Ultrasound with Doppler and MRI facilitates diagnosis and surgical planning, and microsurgical decompression with nerve preservation offers favorable outcomes.