Characteristic eye movements found in Downbeat Nystagmus Downbeat nystagmus (downward fast phase) is the most common of the central vestibular nystagmuses. Its jerk nystagmus waveform begins with upward drift of the eyes corrected with a downward saccade. This form of nystagmus follows Alexander's Law and hence is accentuated by downgaze and also by lateral-down gaze, but is also amplified by convergence and lying prone. Concomitant gaze-evoked nystagmus and rebound nystagmus may be observed. Generally, patients are symptomatic from vertical oscillopsia. The differential for down-beating nystagmus is broad, but structural lesions can be ruled out with neuroimaging. Cervico-medullary junction is the most probable location of a structural lesion. Video by Kathleen B. Digre, M.D. - Moran Eye Center #Downbeat #Nystagmus #Vertical #Ophthalmology #Neurology #Clinical #Video #Ocular #PhysicalExam
