Delayed Resolation Of Hemifacial Spasm After Microvascular Decompression

[Objective] To study the rate, corresponding factors, etiology and prognosis of delayed resolution of hemifacial spasm (HFS) after microvascular decompression (MVD).[Method] The clinical data of415patients with HFS treated by MVD in our department by one certain neurosurgeon from November2006to November2010were collected for analysis of the duration of delayed resolution, preoperative pathogenesis and vessel compression in patients with delayed resolution.[Results] There were106patients (25.5%) with delayed resolution. The duration of delayed resolution was from7days to8months (6weeks in average). There was no correlation between the occurrence of delayed resolution and the sex, age, vessel compression of patients. There was correlation between the occurrence of delayed resolution and the preoperative pathogenesis, degree of severity of HFS. arteriosclerosis and disappearance of abnormal muscle response (AMR) after MVD. There was positive correlation between the duration of delayed resolution and the preoperative pathogenesis.[Conclusion] Delayed resolution is common in patients with HFS treated by MVD. Its etiology is still unknown. The operative effect of MVD for HFS should be evaluated after at least1year of follow-up.