Abstract
Benign paroxysmal positional vertigo developed in a patient with perilymph fistula 3 years after closure of the fistula which was in the lower margin of the annular ligament. The patient's symptoms were long-lasting and intractable. The macula utriculi and utriculoampullary nerve were irradiated by argon laser beams through the stapedectomized oval window. Singular neurectomy was performed using Argon laser, although the nerve could not be identified. After surgery, the patient's symptoms disappeared. Pure tone average of the operated side was 50 dB which remained unchanged after surgery. The macula utriculi may have been completely destroyed. Ocular counter-rolling was indicative of hypofunction of the irradiated utricle. The singular nerve may or may not have been sectioned. The ampullary nerves to the lateral canal and probably the anterior canal were intact, judging from the normal caloric reaction.