右同名半盲と右耳の聴覚障害を呈した1症例

HOMONYMOUS HEMIANOPSIA WITH A HEARING DISORDER, A CASE REPORT

　I．はじめに

　最近，われわれはてんかん発作，右同名半盲，右耳の聴覚障害を同時に呈した症例を経験したので，脳神経学的にその病巣を求める一方，種々の聴覚検査を施行して聴覚中枢の機能を検討したので，ここに報告する。

　The patient a male, aged 26, was found to be suffering from right homonymous hemianopsia, disturbed hearing of the right ear and epilepsy for the period of past 10 years.

　Neurological examination showed a suspected damage of the posterior part of the left internal capsule including the metathalmus; the left medial geniculate body appeared to be somewhat impaired.

　The patient was given, further, a special audiometric tests with following results: 1. The pure tone audiometry and the standard speech audiometry were within normal range for both ears.

　2. The short increment sensitivity index (SISI) test was normal for both ears, showing the functioning of the inner ears to be normal on both sides.

　3. Frequency filtered speech audiometry revealed a poor discrimination in the right ear when a low-passed filtered sound was dilivered. With time interrupted speech audiometry, the discrimination scores were also poorer in the right than the left ear. Distorted speech sounds were discriminated normally in the left ear while the right showed some impairement.

　4. It is said that lesions of the temporal-lobe are bound to impair dichotic listening and musical perceptions, In the present case, however, both of these tests were normal in both ears.