Relationship between Hemifacial Spasm and Ipsilateral Vertebral Artery Deviation

So, Wan-Soo; Park, Seung-Soo; Kwon, Ki-Hun; Koh, Eun-Jeong; Choi, Ha-Young

Original article

Journal of the Korean Society of Stereotactic and Functional Neurosurgery 2008;4(1):1-5.
Published online June 30, 2008.

Relationship between Hemifacial Spasm and Ipsilateral Vertebral Artery Deviation

Wan-Soo So, Seung-Soo Park, Ki-Hun Kwon, Eun-Jeong Koh, Ha-Young Choi

Department of Neurosurgery, Chonbuk National University Medical School, Jeonju, Korea

Abstract

Objective
We investigated the relationship between hemifacial spasm (HFS) and ipsilateral deviation of the vertebral artery (VA).
Methods
Ninety-nine patients with HFS who underwent MVD between March 2001 and February 2007 were compared against 222 normal controls suffered from mild headache or dizziness. Preoperative three-dimensional time-of-flight magnetic resonance angiography (3D-TOF MRA) was used for determining the vascular course.
Results
Deviation of the VA was observed more frequently in the HFS group (67.7%) than in the control group (29.7%) (p< 0.001). The side of HFS and the side of VA deviation were matched in 70.1% of patients (p<0.001). The patients with HFS had a longer distance from midline to the vertebrobasilar junction (VBJ) and a longer distance from midline to the posterior inferior cerebellar artery (PICA) origin than the control group did (in the HFS group, from midline to VBJ=6.17±4.92 mm, from midline to PICA origin=14.3±5.59 mm；in control group, 2.51±3.86 mm, 10.3±4.10 mm, respectively) (p<0.001). Patients with VA deviation have more possibility to suffer from HFS than patients without VA deviation in future (odds ratio=4.92).
Conclusion
HFS and ipsilateral VA deviation are statistically correlated. VA deviation can be regarded as a risk factor for HFS.

Key Words: Hemifacial spasm, Vertebral artery deviation.