Brainstem infarction triggered by the sling technique to treat trigeminal neuralgia caused by a huge vertebrobasilar artery compression

Background: Treating trigeminal neuralgia (TN) caused by a tortuous megadolichoectatic vertebrobasilar artery (VBA) is not uncommon, but may result in adverse events. We report a case of a brainstem infarction, triggered by obstruction of the perforators originating from the huge VBAs, owing to the sling technique. The cistern was too narrowed to pass the sling safely since it was occupied by the huge VBAs. The alternative less invasive and consistent method should be considered in such cases reported. Case description: A 57-year-old man with typical TN caused by compression of huge VBAs was treated using the sling technique by passing a tape through a fenestration near the VBA junction, because no enough space was allowed to pass the sling safely around VBA due to quite narrow superior cerebellopontine cisterns, almost completely occupied by huge VBAs. The small arteries, originating from the huge VBAs could hardly be identified during surgical maneuver. Despite complete relief of the TN, neurological deficit developed, owing to a brainstem infarction evoked by possible obstruction of the VBA perforators and it persisted for approximately 1.5 years. Conclusions: To our knowledge this is a first reported case of an adverse event triggered by the sling technique used during MVD. An incidental obstruction of perforators originating from huge VBAs may induce adverse events, because an identification of perforators from VBA is hardly possible in such cases. Despite the effectiveness of the sling technique in treating TN, surgical procedure is quite complicated, particularly when cisternal space around huge VBAs are too narrow to pass the sling safely. The alternative less invasive and consistent decompression method, such as a use of strong adhesives to mobilize and fix the VBA should be attempted instead of the sling technique to avoid adverse events.