Quantitative vestibular function testing in elderly patients with dizziness.

Electronystagmography was used to examine 103 elderly patients complaining of dizziness. This series of tests included tests for pathologic nystagmus, saccades, smooth pursuit, and optokinetic nystagmus, as well as bithermal caloric testing and rotational testing. One or more specific diagnoses were identified in 100 patients (86.2%), with the two most common diagnoses being benign positional vertigo (30 patients, or 25.9%) and cerebrovascular disorders (25 patients, or 21.6%). An abnormality was found on ENG in 75 (65%) of the patients tested, the most common of these being a unilateral hypoexcitability to caloric stimulation. In most cases, the ENG data was used to support a presumptive diagnosis that was based on the patient's history and examination, although in 4 cases ENG provided the critical diagnostic information by identifying decreased caloric and rotational responses in patients with nonspecific dizziness and dysequilibrium.