Effect of electric stimulation on vestibular compensation in guinea pigs.

The effect of electric stimulation on vestibular compensation was studied in guinea pigs. Pharmacological labyrinthectomy was performed by injecting chloroform into the right middle ear under light ether anesthesia. The guinea pigs were divided into four groups: a control group which was not electrically stimulated after labyrinthectomy, a group stimulated with 0.6 mA square wave, a group stimulated with 0.3 mA square wave, and a group stimulated with 0.6 mA pulse wave. Electric stimulation, which started 1 h and 15 min after labyrinthectomy, was given through retroauricular electrodes. Nystagmus and head deviations were recorded and analyzed to assess the process of compensation at 1, 2, 3, 4, 5, 8, 12, 18 and 24 h after labyrinthectomy. Electrically stimulated groups, especially group 0.6 mA square wave and group 0.6 mA pulse wave, showed faster compensation in nystagmus and head-body deviation than the control group. Therefore, in this study, electric stimulation seemed to contribute favorably to vestibular compensation.