A system of surgical treatment for episodic vertigo was introduced by the authors. This system was divided into three steps as follows:
The first step: Perivascular sympathectomy at the proximal part of the vertebral artery
The second step: Extradural endolymphatic sac operation (Portmann's operation)
The third step: Destructive operation of the labyrinth
Perivascular sympathectomy of the vertebral artery was possible to prevent episodic vertigo without any surgical trouble. But, hearling improvent was not found by this operation. Portmann's operation showed good results on the improvement of hearling loss as well as vertigo in cases of Meniere's disease with the glycerol effect. The third step operation was not necessary except one case treated by ultrasonic ir- radiation.