Establishment of Normal Values for Objective Evaluation of Ocular Movements Using Videonystagmography

This study aims to establish a set of normal values for the objective evaluation of ocular movements using videonystagmography (VNG). Thirty individuals aged between 18 and 50 years, with no history of vestibular symptoms, recurrent headaches, central nervous system (CNS) symptoms, or cochlear symptoms, were selected. The assessment of five types of ocular movements (saccades, pursuit, optokinetic tests, spontaneous nystagmus, and gaze tests) were conducted using VNG. Normal ranges were established for different parameters of saccades, including latency, precision, and velocity in both horizontal and vertical directions for each eye. Pursuit gain was calculated for each eye in all four directions. Optokinetic gain was determined when the stimulation screen moved in all four directions. Symmetric responses were observed in all subjects. No spontaneous nystagmus was observed with fixation, although two participants exhibited nystagmus upon removal of fixation. Gaze tests revealed no abnormalities.