Recovery of gaze disturbance in bilateral labyrinthine loss.

Recovery of gaze disturbance was studied in 15 patients with bilateral labyrinthine loss who underwent active or passive rotation tests at various times after onset, 1 month to 34 years. Mean VOR gain increased rapidly against the logarithm of time under active rotations and slowly under passive rotations. Although gaze disturbance recovered in the 1st year under both active and passive rotations, active ones resulted in better gaze stabilization at higher frequencies. The present study indicated that initiation and increase of compensatory eye movement in the dark during the critical period, i.e., early in the 1st year, underlies the compensation for gaze disturbance after bilateral labyrinthine loss, similarly as in the case of unilateral lesions.