Acoustic neuroma: clinical aspects, audiovestibular assessment, diagnostic delay, and growth rate

The diagnostic findings in 300 patients with acoustic neuromas are reported. Because of a centralized treatment of acoustic neuromas, we have a uniform diagnostic work-up of all patients, which enables us to make a nonselected comparison of the diagnostic efficiency of the various tests. In patients with hearing better than 80 dB, a normal auditory brainstem response, the presence of recruitment, and normal caloric reaction, the presence of a tumor can be excluded. In patients with poor hearing, tomography is necessary if one does not prefer to perform CT directly. If CT, even with contrast enhancement, is negative, we continue to perform air CT. Only then do we know whether or not the patient has a tumor. Magnetic resonance imaging has not been available to us, but with this diagnostic modality even intrameatal tumors are visualized. However, with the present economy involved with magnetic resonance imaging it is not realistic at the present time to use this way of imaging as a screening procedure. In spite of an intensive campaign for making early diagnosis of acoustic neuromas, our attempts have not been successful, since we have even more tumors measuring over 40 mm in diameter among the latest 100 patients than among the first one hundred. Both patients and physicians (otologists) to some extent are still ignoring the possible significance of a unilateral, progressive, sensorineural hearing impairment. Guidelines for improving this situation are given. Twenty-one patients were followed for an average of 4 years, repeated CT scans were performed, and the tumor appeared to be progressing to a size requiring surgical intervention in only three of these patients.(ABSTRACT TRUNCATED AT 250 WORDS)