顔面痙攣血管除圧手術 : 再発原因と再発予防および合併症発生予防のための手術留意点

One hundred and thirty two patients with typical hemifacial spasm (HFS) were treated by microvascular decompression (MVD) of root exit zone of facial nerve. Among of them 5 patients awoked with spasm from anesthesia of MVD ( immediate type ), and 15 patients experienced of recurrence of spasm between post operative 2 days to 7 days ( early type ). In our cases recurrence of spasm after two weeks had not been encountered ( late type ). Five of all immediate type and 3 of early type had second operation of MVD during the period of post operative 2 day to 4 months and their spasm was completely relieved in immediate fashion. By course observation of 13 early type, the spasm of 8 patients disappeared gradually within two weeks, in 2 patients relief of spasm needed 6 months respectively, in 2 patients their spasm continued during the followup of 22 months and 28 months. One patient whose offending vessel was not identified by MVD had no relief of spasm. In summary HFS was completely relieved in 129 patients ( 97.7% ) at the follow-up period ranging lyear to 8 years. According to author's experience of second operation of MVD, the causes of recurrence of spasm were found as follow, in 3 cases driving force of vertebral artery pulsation beeing reached to root exit zone through prosthesis, missing of another offending artery in 2, missing of other compression at more proximal site in 2, inappropriate size and location of prosthesis in 1. The operation strategy for achievement of excellent result of MVD and for preventing of complication is discussed.journal articl