Abstract
A woman, aged 56, was admitted to a hospita because of diabetic coma on Jan. 14, 1977, and complained of a gradually progressed hearing loss in both ears without vestibular symptoms after recovering from coma. About three months after attack, audiological examination showed bilaterally symmetrical sensory hearing loss of a severe flat type. Hearing test showed 10 to 20dB deterioration in 3, 4 and 6kHz after peroral taking of 50g. glucose. Vestibular function test showed diminished caloric reaction in both ears. Although her diabetes became well controled, nephropathy and retinopathy (Scott V) were still remained.
The following considerations were obtained.
1. It was assumed that circulatory disturbance of the inner ears might be caused by increased viscosity of blood, stagnation of blood stream, tissue hypoxia and subsequent clot in capillary vessels i.e. hemorheologic change.
2. Hearing deterioration observed during the glucose tolerance test was thought to be caused by hyperglycemia.
