Internal Neurolysis with and without Microvascular Decompression for Trigeminal Neuralgia: Case Series

OBJECTIVE: Microvascular decompression (MVD) has remained the first-line surgical treatment of trigeminal neuralgia when an offending vessel can be identified that is causing neurovascular compression. However, patients without neurovascular compression can either develop trigeminal neuralgia or recurrence after MVD. In addition, patients with venous and less severe arterial compression have been shown to have reduced efficacy after MVD. Internal neurolysis is a surgical technique used to separate the fascicles of the trigeminal nerve and might be a good option for patients with trigeminal neuralgia but without vascular compression. METHODS: A retrospective, institutional review board approved medical record review was performed of adult patients with trigeminal neuralgia who had undergone internal neurolysis. The search resulted in 32 patients who had been treated from 2016 to 2019. The Barrow Neurological Institute (BNI) pain intensity scale and hypesthesia scale (HS) were used to determine the outcomes. RESULTS: The average follow-up was 20 months (range, 3-40 months). The postoperative outcomes showed a BNI pain intensity scale score of I for 50%, with excellent control in 56%, successful control in 78%, adequate control in 94%, and poor control in 6%. Significantly more patients without previous treatment had had successful pain control (95% vs. 54%). Six patients (19%) experienced pain recurrence and were significantly more likely to experience pain recurrence compared with patients without a previous procedure (39% vs. 5%). The overall BNI-HS score post-operatively was I for 28%, II for 69%, and III for 3%. CONCLUSIONS: Internal neurolysis with and without MVD has shown efficacy in treating trigeminal neuralgia in carefully selected patients.