Value of Rotational Tests in the Diagnosis of Vestibular Disease

Abstract

Caloric irrigation of the external ear canal represents an inadeqwte vestibular stimulus because the method is not physiologic and the canal irrigation and the heat transfer to the inner ear cannot be well controlled. In rotational testing an accurate acceleration profile can be applied with an appro riate rotating device. A test procedure is presently being for 240 seconds, followed by a similar deceleration (equivalent to acceleration in the revelse direction) and hold. On-line data reduction of the nystagmus response is accomplished automatically using a simple analog technique. This technique provides a concise presentation (on a standard size sheet of paper) of the total slow phase eye displacement resulting from the primary and secondary responses and enables comparison of the results for both directions of acceleration. Experience with the routine use of rotational testing in a vestibular clinic and the significance of various paterns of response with special emphasis on vestibular adaptation function are discussed.used, which consists of constant acce P eration at 3"/sec2 for 50 seconds, hold at constant velocity

Vestibular Dysfunction and Psychopathology

“…Since calorics permit separate stimulation of each labyrinth, this should be the preferred method of assessing suspected peripheral vestibular disease. However, particularly in the case of possible CNS involvement, phase and gain measures yielded by rotatory tests contain useful diagnostic information, especially when combined with tests of visualocular control (McClure, Lycett, and Johnson 1973;Zee et al 1976;Wolfe et al 1978;Baloh, Sills, and Honrubia 1979) and would be of great interest if applied in research on psychiatric populations.…”