The Morphololgical Changes of the Vestibular Organ Following Electrical Stimulation

Changes of the Utricle and Lateral Semicircular Canal

Abstract

The morphological changes of the vestibular organ of the guinea pig following extracochlear electrical stimulation were investigated using scanning electron microscope.
Positive and negative square wave pulse stimulation were given through the silver ball electrode placed on the round window membrane. The current intensities used in this experiment were 100,200 and 300μA.
Direct current stimulation at the intensity of 300μA caused severe damage to the utricular macula and the ampullar crista of the lateral semicircular canal. The degenerative changes such as fusion of sensory hairs, protrusion of the cuticular plate and loss of sensory cells were found on both the utricle and the semicircular canal. In the most severely damaged area, the basement membrane of the macula was destroyed.
In the clinical application of direct current stimulation to the inner ear for relieving tirihitus, special attention should be payed to the vestibular organ.