[Transposition technique of microvascular decompression for hemifacial spasm without using a brain retractor].

A unique transposition technique in microvascular decompression for hemifacial spasm (HFS) was employed in patients with compression by either the peripheral artery or the main trunk of the vertebral artery. Complete transposition that secured free space between the offending artery and the root exit zone (REZ) was accomplished by introducing GORE-TEX tape around the artery and suturing it to the petrous dura. An adequate working space, as if operating in a shallow basin, was essential. Throughout the procedure, it was not necessary to use a brain retractor. Instead, a gentle wrapping retraction technique using a sucker was employed over the brain covered by a sheet of Gelfoam (Pfizer Japan Inc., Tokyo) and cotton. All patients showed complete cure of HFS immediately after surgery with this technique. The difficulty of transposing the vertebral artery can be overcome by well-designed surgical strategy and skillfulness.