[Amplitude summation and the pendulum test as elements of the otoneurologic examination]

Vestibular tests were performed in more than 600 otoneuological patients. The data analysed included the otoneurological history, audiograms, observation of spontaneous nystagmus, caloric and swing tests, and recording by electronystagmography. The tracings were subjected to summation of the amplitudes of the slow-phase nystagmus and classification of the recording as peripheral (small amplitude, high frequency) or central (dysrhythmia with bouts of high-frequency nystagmus). The correlations between spontaneous nystagmus and directional preponderance in caloric and rotation tests are complex, and our results show that an isolated abnormality has little significance. The expected correlation between hearing loss and unilateral caloric paresis was confirmed. Other lesions, such as peripheral or central ENG tracings and reduced vestibular reaction, did not correlate with any other pathological finding. Directional preponderance and spontaneous nystagmus were significantly more frequent in patients with unilateral caloric paresis than in those with a symmetrical response. The incidence of a peripheral type of ENG tracing, hearing loss and unilateral paresis increased with the age of the patients. Reduced vestibular response, a central type of tracing and directional preponderance did not correlate with age. The well-known variability of the subjective threshold of vertiginous sensations was confirmed by the results in patients with no vertigo, and deserves more attention.