"Macrovascular" Decompression of Dolichoectatic Vertebral Artery Causing Hemifacial Spasm Using Goretex Sling: 2-Dimensional Operative Video.

Abstract

Hemifacial spasm is characterized by painless and involuntary spasms of the muscles supplied by the facial nerve, most commonly involving the orbicularis oculi. The most common cause of hemifacial spasm is compression of the facial nerve's root by the anterior inferior, or posterior inferior, cerebellar arteries (AICA or PICA). However, in <1% of cases, the compression can be due to a dolichoectatic vertebral artery. Microvascular decompression using Teflon patties may be sufficient when the offending artery is small (eg, AICA or PICA). However, the size and tortuosity of the vertebral artery (especially one that is dolichoectatic) may require a more robust means of decompression (ie, "macrovascular decompression"). In this operative video we demonstrate our technique for managing a patient with hemifacial spasm due to a dolicoectatic vertebral artery. We use a Goretex® (W.L. Gore & Associates Inc, Newark, Delaware) sling secured to the dura of the posterior petrous ridge to suspend the vertebral and posterior inferior cerebellar arteries, thereby decompressing the root entry zone of the facial nerve. Teflon felt pieces are added as a second layer of security. Key steps to this technique include: (1) visualization of the root entry zone, (2) extensive arachnoid dissection to allow adequate mobilization of the vertebral artery, 12 and (3) securing the sling in a trajectory that prevents kinking of the vertebral artery and its branches.