A CASE OF FRONTAL LOBE CYSTOMA COMBINED WITH IPSILATERAL DEAFNESS

Abstract

The authors reported a 32-year-old woman suffered from the cystoma in the left frontal lobe (Fig.3). Her hearing acuity on the same side was impaired with the type of gradual high tone loss by about 40 db (Fig.1-2). Moreover, when the pressure of the cerebrospinal fluid elevated, the hearing acuities on both sides were temporarily impaired for low tones (Fig.1), that is to say, the hearing of the left ear was impaired for all tones. At the autopsy, the atrophy and the edema of the nerve cells due to the tumor were revealed in the Heschl's gyrus of the left temporal lobe (Fig.4-11). The bilateral low tone deafness might be due to the transient hydrops of labyrinth and the compression to the trunk of the cochlear nerve, that were induced by the elevated pressure of cerebrospinal fluid, and the high tone deafness on the left side partially might be due to the degeneration of the temporal lobe, which was mentioned above. The localization of the cerebral acoustic area was discussed from the following fact that the hearing acuity on the opposite side was almost intact in spite of the degeneration of the temporal lobe.