Application of argon laser to the inner ear.

The effects of argon laser irradiation on the inner ear were studied morphologically. The stria vascularis showed focal coagulation, vesicle formation, perforation and atrophy after irradiation through the otic capsule. These changes vary according to the power and duration of irradiation. Atrophy of the stria vascularis can be produced without injuring the organ of Corti, by suitable application of the laser beam. The round window membrane transmits the argon laser. Tissues in the hook region and a part of the lower basal turn demonstrated changes of varying degree. Loss of the nerve fibres was observed in the osseous spiral lamina, which was fractured and dislocated. Irradiation through the stapedectomized oval window destroyed the macula sacculi without rupturing the saccular wall.