Clinical analysis of hemifacial spasm patients with delay symptom relief after microvascular decompression of distinct offending vessels

This study investigates symptom relief in patients whose hemifacial spasms (HFS) were completely relieved following microvascular decompression (MVD). Patients with HFS who were operated on from January 2007 to May 2011, at our department, were studied. The medical records and operation videos of each patient were reviewed. Follow-up was performed via telephone communication. A total of 410 patients with HFS were divided into two groups: Group A (277 cases): HFS caused by small vascular compression, and Group B (133 cases): HFS caused by vertebral artery compression. Magnetic resonance imaging (MRI) was performed on all the patients to rule out those with secondary HFS. Patients who had undergone previous MVD were also excluded at that time. In all, 462 patients underwent MVD for HFS in our center during the study period. Follow-up was available for 410 patients. In the small vascular compression cohort, 72 (72/277, 26.0 %) HFS patients achieved relief with delayed healing. While in the vertebral artery compression cohort, 52 (52/133, 39.1 %) HFS patients experienced relief with delayed healing. There was significant difference between these two cohorts (P < 0.05). 93.75% of delayed healing patients were cured and experienced spasm relief within 6 months. Surgeons should be aware that delayed symptom relief after MVD for HFS is more common than has been reported, and time course of symptom relief is various as well as unpredictable; however, most HFS patients are cured, and experience spasm relief within 6 months.