[Otoneurological evaluation of the acoustic tumor, with special reference to the diagnosis of small tumors].

Seventy one cases of the acoustic tumor experienced in our clinic from 1978 to 1983 were analysed in the light of the diagnosis of a small size tumor. Although the incidence of the abnormal findings in the X ray examination was almost equal irrespective to the size of the tumor, the abnormality in hearing and caloric tests was less frequent in the small tumor than in the large one. Only half of the cases showed the abnormality in all these examinations. Consequently, any patient exhibiting the abnormal finding, at least, in one of them should be further examined until proven to be otherwise. ABR was abnormal in all cases and considered to be very important for the detection of the small tumor. The importance of thin section CT scan and Air CT cisternography for the detection of the small tumor was stressed.