1987 Volume 1987 Issue Supplement09 Pages 17-23
Inverted nustagmus often occurs after hot air caloric stimuration in an ear with tympanic membrane perforation or moistend ear cavity without disorder of the vestibular system. To this inverson, we calculated the heat value transferred during the air caloric test, estimated the temperatures that yield a heating of +20.5 cal or a cooling of -20.5 cal using dry or full humidified air in dry or wet ear cavity.
This calculation of heat value and temperature was done under the assumption that the heat transfer coefficient is 100%; thus, the data do not represent the actual amount of heat that is transferred but is only the relative change in temperature.
When the ear cavity is dry, a commercially available air caloric stimulator provides reliable test data. However, when the cavity is wet, the effect of cooling by evaporation must be taken into consideration.
