[Neurovascular interactions in hemifacial spasm]

The article describes our results of surgical treatment of 37 patients with hemifacial spasm (HS) as well as results of morphological studies of facial nerve root exit zone (REZ). Morphological studies demonstrated that extension of central myelinated zone differed between 0.9 and 3.6 mm (mean 2.24 mm). This zone did not exceed 1.1 diameter of facial nerve. Intraoperative findings included 27 cases of compression by a single vessel and 9 cases of compression by multiple vessels. In cases of compression by a single vessel the offending artery was AICA in 11 cases, PICA in 12 cases and VA in 4 cases. In 35 patients complete decompression of facial nerve REZ was achieved. In one case complete decompression was not possible due to penetration o vestibular nerve by AICA which prevented safe manipulations of the artery and nerves. Excellent results of surgical treatment were achieved in 33 patients. In 1 described case the outcome was unsatisfactory. We observed no serious postoperative complications. Vascular decompression is highly effective and relatively safe procedure for treatment o HS. HS results from compression of central myelinated zone of facial nerve thus surgical decompression should be preformed close to REZ at the brainstem.