CASI CLINICI   

Chirurgia 2015 February;28(1):27-30

Copyright © 2015 EDIZIONI MINERVA MEDICA

lingua: Inglese

Hemifacial spasm caused by an offending vein and its treatment by vein-preserving microvascular decompression surgery: a case report

Xiong N. X., Zhao H. Y.

Department of Neurosurgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P. R. China

It is generally considered that hemifacial spasm (HFS) is caused by arterial or venous compression at the root exit zone (REZ) of the facial nerves. As offending vessels, arteries and veins have distinct morphological and structural characteristics. Clinical cases with veins as offending vessels are relatively rare and, thus, our understanding of this type of disorder has been limited. Herein, we reported a case that presented left HFS with a vein as the offending vessel, also examining the microsurgical anatomy of the vein associated with REZ. In a 50-year-old female, preoperative magnetic resonance image revealed a vessel attached at the surface of the medulla oblongata. It extended upward straightly along the roots of the lower cranial nerves, compressing the REZ of the seventh cranial nerve. This offending vessel was identified as a vein according to its anatomical characteristics. Microvascular decompression surgery of the left seventh cranial nerve was performed using the lateral retrosigmoid/suboccipital approach. The HFS was completely resolved immediately following the surgery. The postoperative course was uneventful with no signs of either facial paresis or any new deficits. There was no recurrence of HFS throughout the entire 18-months follow-up period. Our observations and surgical procedures may provide a new insight into the underlying mechanisms of HFS and an example of effective treatment of this particular type of disorder with preservation of the offending vein without coagulate or cut it.