Petrosal Vein Involvement in Neurovascular Conflict in Trigeminal Neuralgia: Surgical Technique and Clinical Outcomes

BACKGROUND: Contact of the main stem of the petrosal vein (PV) to the nerve root is a rare cause of trigeminal neuralgia (TGN). The implication of the PV in relation with neurovascular contact (NVC) is not fully understood. OBJECTIVE: To assess the operative procedures in microvascular decompression (MVD) in patients with PV involvement in the long-term. METHODS: We retrospectively reviewed 34 cases (7.0%) in 485 consecutive MVDs for TGN, whose PV main stem had contact with the trigeminal nerve root (PV-NVC). PV-NVCs were divided into 2 groups: concomitant arterial contact or no concomitant arterial contact. Surgical techniques, outcomes, complications, and recurrence were assessed. RESULTS: The anatomical relationship of the PV with the trigeminal nerve root was consistentwith preoperative 3-dimensional imaging in all patients. Pain reliefwas obtained in most patients immediately after surgery (97.1%) by separating the PV from the nerve root. Postoperative facial numbness was noted in 9 patients (26.5%). Symptomatic venous infarctions occurred in 2 patients (5.9%). Recurrence of facial pain occurred in 3 patients (8.8%) with a median 48 mo follow-up period. Re-exploration surgery revealed adhesion being the cause of recurrence. The statistical analyses showed no difference in the surgical outcomes of the 2 groups. CONCLUSION: Separating the PV from the nerve root contributes to pain relief in patients with PV conflict regardless of concomitant arteries. Preserving venous flow is crucial to avoid postoperative venous insufficiency.

Automated summary

This study retrospectively reviewed 34 cases of PV-NVC patients who underwent MVD, and found that separating the PV from the nerve root can provide pain relief for the majority of patients, but postoperative complications such as facial numbness and venous infarctions may occur.