Vestibulo-ocular reflexes in peripheral labyrinthine lesions: II. Caloric testing.

In a group of patients with unilateral labyrinthine dysfunction, the maximal velocity of the slow component response to caloric stimulation was compared with that to horizontal vestibular rotatory stimulation by a low-frequency stimulus. It was found that the larger the magnitude of the caloric response, the larger were the gain and sensitivity of the vestibulo-ocular reflex induced by physiologic stimuli. Rotary stimulation of patients with only one functioning inner ear provides information equivalent to that obtained from caloric stimulation and allows more rigorous quantification of the state of the vestibulo-ocular reflex.