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Background and Objectives:The otolith organs serve for gaze stabilization, posture control, and spatial orientation by horizontal semicircular canal. Unilateral otolithic dysfunction canot be identified and lateralized because a surviving intact otolith can support bidirectional responses. The aim of study was to test unilateral otolith function by applying caloric stimu-lation to unilateral labyrinth. Materials and Method:We made a magnetic search coil system combined with tilt apparatus for a rabbit and measured three-dimensional eye movements. Responses were evoked by position change and cold caloric ing eye deviations were observed. Results:Static head tilts produced compensatory eye deviations. In the resting position, after cold caloric stimulation of each ear, the directions of eye deviations were in reverse of the vertical eye movement plane. In both lateral tilt positions, the eye deviations decreased after caloric stimulation of the lower ear, and increased after stimulation of the upper ear in the vertical plane. In the pitch down position, the eye deviations decreased after caloric stimulation of each ear in the torsional plane. Conclusion:Cold caloric stimulation evoked regular dynamic changes of the otolithic eye deviations produced by static head positions. We propose that this method might be useful for lateralization and evaluation of the unila-teral otolith dysfunction. (Korean J Otolaryngol 2002;45:747-54)