Trigeminal Neuralgia Caused by Dural Arteriovenous Fistula of the Transverse-Sigmoid Sinus without Vessel Compression at Root Entry Zone

OBJECTIVE: The vessel compression at the root entry zone (REZ) of trigeminal nerve is a common cause of trigeminal neuralgia (TN). We report a rare case of TN caused by dural arteriovenous fistula (DAVF) of the transverse-sigmoid sinus without vessel compression at REZ. CASE PRESENTATION: A 45-year-old woman presented with right side tinnitus and was diagnosed as a DAVF of the right transverse-sigmoid sinus (Borden Type I). After that, the facial pain in the right maxillary nerve area appeared and was getting worse. DSA revealed an enlargement of the artery of foramen rotundum (AFR) as one of the feeding arteries. MRI revealed no evidence of vascular compression at REZ. The patient was treated with transarterial embolization (TAE) with Onyx via the branches of the middle meningeal artery (MMA) and occipital artery (OA). The AFR decreased in size and the facial pain was improved. However, the DAVF and the facial pain were recurred. Finally, the DAVF was completely embolized with transvenous embolization (TVE). During 1-year follow-up period, the patient remained free of pain without recurrence. CONCLUSION: The compression of the maxillary nerve by the AFR might result in TN, because the pain diminished after shrinkage of the AFR by the endovascular treatment.