NYSTAGMUS MEASURED BY ENG AFTER STAPES SURGERY

Much attention has been paid to hearing results after stapes surgery, but the risks of vestibular disturbance has not been extensively studi ed. Postoperative spontaneous nystagmus was measured daily at bedside by portable ENG in order to evaluate the vestibular damage from stapes surgery. Thirteen patients underwent primary stapedotomy or stapedect omy from August 1, 1992 to June 30, 1993. Nystagmus toward the operate d car was observed in 3 cases, that toward the opposite ear in 2 cases . that changing from toward the operated ear to toward the opposite ea r in 2 cases, that changing from toward the opposite ear to toward the operated ear in 2 cases and no nystagmus in 4 cases. There was no rel ationship between duration of nystagmus and that of dizziness. Nystagm us was thought to be due to the following: i) inner ear damage by oper ation, iii postoperative perilymphatic fistula iii) floating footplate , and it) stimulation of hair cells by high potassium ion in the peril ymph due to blood flow into the inner ear.