[A case of cortical deafness following bilateral putaminal hemorrhage]

A 59-year-old man had suffered from consciousness disturbance and right hemiplegia in December, 1996. He was diagnosed as left putaminal hemorrhage and his symptoms improved by conservative treatment. After one week since the onset, when he became alert, he noticed deafness. He was admitted in our hospital because of deafness and dysarthria in March, 2001. T 1-weighted MR image of the brain revealed bilateral putaminal hemorrhage and a low signal area in the white matter of right temporal lobe. Single photon emission computed tomography image revealed hypoperfusion in the bilateral temporal lobes. His electrocochleogram and auditory brainstem response were normal. Audiogram revealed increased air and bone conduction thresholds. Therefore, we diagnosed his condition as cortical deafness. He could only recognize loudness as the sound by the electrical promontory test. These results indicate that his cortical deafness might be caused by his bilateral acoustic radiation damage associated with the right partial temporal lobe damage and that some fibers of the acoustic radiation, which were responsible for the recognition of loudness of sound, were spared. Therefore he has a possibility of regaining hearing capability by a cochlear implant.