Surgical Management of Trigeminal Neuralgia Induced by Brainstem Infarct: A Systematic Review of the Literature.

BACKGROUND: Although cases of trigeminal neuralgia (TN) induced by brainstem infarct have been reported, the neurosurgical literature lacks a comprehensive review for this subpopulation of patients. We present the first systematic review of the literature to discuss pathology, surgical management, and future directions for therapeutic innovation in this population. METHODS: Our systematic review was conducted according to PRISMA guidelines. Resulting articles were screened for those that presented cases of TN associated with brainstem infarct. RESULTS: A review of the literature identified 18 case reports of 21 patients with TN induced by brainstem infarct: 14 pontine infarcts and 7 medullary infarcts. Although many cases of ischemic brainstem lesions are caused by acute stroke, cerebral small vessel disease also plays a role in certain cases, and the relationship between these chronic lesions and TN is more likely to be overlooked. Furthermore, we found that reports of self-resolving TN pain after brainstem infarct is disproportionately biased, as most case reports published their data within the first few months after initial presentation. Reports with follow-up periods >13 months reported eventual pain recurrence that necessitated surgical intervention. Microvascular decompression was not sufficient to treat TN pain associated with concurrent neurovascular compression and brainstem infarct. CONCLUSIONS: Brainstem infarcts affecting the trigeminal pathway represent an understudied pathologic cause of TN. Although the neurosurgical literature lacks a clear picture of the most efficacious interventions in this population, we are optimistic that this review will encourage further investigation into the best treatment for these patients.

Trigeminal neuralgia induced by brainstem infarction treated with pontine descending tractotomy: illustrative case.

BACKGROUND: While cases of trigeminal neuralgia induced by a brainstem infarct have been reported, the neurosurgical literature lacks clear treatment recommendations in this subpopulation. OBSERVATIONS: The authors present the first case report of infarct-related trigeminal neuralgia treated with pontine descending tractotomy that resulted in durable pain relief after multiple failed surgical interventions, including previous microvascular decompressions and stereotactic radiosurgery. A neuronavigated pontine descending tractotomy of the spinal trigeminal tract was performed and resulted in successful pain relief for a 50-month follow-up period. LESSONS: While many cases of ischemic brainstem lesions are caused by acute stroke, the authors assert that cerebral small vessel disease also plays a role in certain cases and that the relationship between these chronic ischemic brainstem lesions and trigeminal neuralgia is more likely to be overlooked. Furthermore, neurovascular compression may obscure the causative mechanism of infarct-related trigeminal neuralgia, leading to unsuccessful decompressive surgeries in cases in which neurovascular compression may be noncontributory to pain symptomatology. Pontine descending tractotomy may be beneficial in select patients and can be performed either alone or concurrently with microvascular decompression in cases in which the interplay between ischemic lesion and neurovascular compression in the pathophysiology of disease is not clear.