Efficacy of a monothermal warm water caloric screening test.

The validity of using monothermal caloric screening tests to shorten bithermal caloric test time has been disputed by several investigators. The purpose of this study was to reexamine the efficacy of a monothermal warm caloric screening test. Two retrospective investigations (n = 130) served to generate normative data and provide an estimate of the false-negative rate of the warm monothermal caloric screening test. A prospective investigation (n = 30) was also conducted. Predictions were made regarding bithermal caloric test normality from warm monothermal data, and the bithermal test was completed. The results of this prospective investigation suggested that a warm monothermal screening test can predict normal bithermal caloric responses with greater than 97% accuracy. Criteria for normality include less than 29.54% warm caloric maximum slow phase eye velocity (SPEV) interaural difference, maximum SPEVs that are greater than 11 degrees/s for each ear, absence of significant positional or spontaneous nystagmus, and normal ocular motility.