Simple Microvascular Decompression for Hemifacial Spasm Caused by Dolichoectatic Vertebral Artery

Abstract

Background and importance: Hemifacial spasm (HFS) secondary to a dolichoectatic vertebral artery (VA) is a rare but debilitating condition. Macrovascular displacement of the vessel away from the nerve using a Teflon sling is an effective, but not always feasible, method. Transection, relocation, and reanastomosis of the dolichoectatic VA has also been described but presents a significant surgical challenge and carries a higher risk profile. In this case report, we demonstrate that simple microvascular decompression by translocation of the compression point away from the root entry zone (REZ) is an effective measure in treating HFS in this setting.

Clinical presentation: A 67-year-old patient presented with debilitating left-sided HFS secondary to a large torturous VA abutting the facial nerve root entry point at the brainstem. The patient underwent retrosigmoid craniotomy, and the dolichoectatic VA was able to be mobilized away from the REZ, although compression remained along the cisternal segment. Using Teflon pledgets, the compression point caused by the VA at the REZ was carefully padded, and despite residual compression in the more distal cisternal nerve segment, the patient experienced complete resolution of symptoms.

Conclusion: HFS caused by a dolichoectatic vessel poses a challenge for complete surgical decompression. We demonstrate that decompression of the REZ alone represents a simple and effective solution, resulting in complete resolution of the symptoms without the need to resort to more complex and potentially riskier options.

Keywords: Dolichoectatic vertebral artery; Hemifacial spasm; Root entry zone.