Recognition and Management of Offending Vessels in the Treatment of Hemifacial Spasm with Microvascular Decompression:Analysis of 78 Cases

Objective To analyze the anatomical relationship between the offending vessels and the facial nerve in hemifacial spasm(HFS) and to provide anatomical basis for microvascular decompression(MVD) in patients with HFS.Methods The clinical data of 78 patients with HFS treated with MVD were analyzed retrospectively to find out whether the offending vessels existed or not and their origin and running course,and to summarize the efficacy of microvascular decompression on hemifacial spasm.Results There were offending vessels in 77 patients(98.72%)out of the 78 patients with HFS,including 39 cases(50.00%) of anterior inferior cerebellar artery(AICA),21 cases(26.93%) of posterior inferior cerebellar artery(PICA),10 cases(12.82%) of AICA and PICA,3 cases(3.85%) of PICA and vertebral artery(VA),2 cases(2.56%) of AICA and VA,and 2 cases(2.56%) of AICA,PICA and VA.1 case(1.28%) had no offending vessels.The spasm disappeared immediately after the operation in 72 patients,and the symptoms of spam improved significantly in 5 patients,who were cured in three to six months.Conclusion Vascular compression may be the main cause of HFS,and the operation of MVD for HFS could achieve satisfactory efficacy.Exposing REZ during operation,accurately identifying the offending vessels,fully decompressing of REZ,the size of graft and the location of graft are important factors influencing surgical efficacy.