The pitfalls of limiting ENG testing to patients with vertigo.

A high incidence of patients who do not experience vertigo with unilateral vestibular disease has been observed. Recognizing that many clinicians perform electronystagmographic vestibular testing on only patients who describe vertigo, a retrospective study of 229 patients was designed to study the potential pitfalls of this practice. The results confirm a preliminary study and show that 66% of the patients described no vertigo. Included were 13 intracranial lesions of which only one had the classic symptom. Differences in cortical perception and adaptation are postulated as factors responsible for these and other observations relative to caloric stimulation, torsion swing testing, and the presence of spontaneous nystagmus.