Microvascular decompression for recurrent trigeminal neuralgia.

Recurrence of trigeminal neuralgia (TN) symptoms after microvascular decompression (MVD) is a challenge for neurosurgeons. This study evaluates the indication, efficacy and safety of re-do MVD. We retrospectively reviewed consecutive patients who underwent MVD for TN from January 2000 to June 2012. The parameters of study interest were pre-operative magnetic resonance tomographic angiography (MRTA) findings and operative findings. Pain outcome was scored using the Barrow Neurological Institute (BNI) grading scale. Twelve patients underwent re-do MVD following recurrence of pain. Vascular compression was detected on pre-operative MRTA images in eight patients, a small mass was found in two patients, and pre-operative imaging was negative in two patients. Of the eight patients with a positive finding of arterial conflict, a vascular loop was identified intra-operatively in five patients (62.5%); in two (25.0%) a small granuloma filled with Teflon fibers was found compressed the trigeminal nerve; and in one patient (12.5%) only dense arachnoid adhesions were found around the trigeminal nerve. For the two patients with mass compression on MRTA images, a granuloma was found during operation. Neurovascular compression was found in the two patients with negative preoperative MRTA images. Re-do MVD is a safe and effective treatment for recurrent TN when indicated by a prolonged pain-free period following the first surgery.