Ocular Bobbing

    • Intermittent, nonrhythmic rapid vertical conjugate movements of the eyes followed by slow return movements to primary gaze position
    • Variants include
      • Slow downward movements followed by rapid upward movements (“ocular dipping”)
      • Rapid upward movements followed by slow downward movements (“reverse ocular bobbing”)
      • Slow upward movements followed by rapid downward movements (“reverse ocular dipping”)
    • Direction or speed of the first eye movement probably does not carry any differential diagnostic value
    • Patient is usually unconscious
    • Attributed to release of midbrain-mediated vertical eye movements by failure of cerebral or pontine inhibition
    • Common causes: anoxic or metabolic encephalopathy, pontine hemorrhage or infarct
    • Core clinical features
      • Ocular bobbing: the initial conjugate eye movements are fast and downward, followed by slow upward movements
      • Variants of ocular bobbing: the initial movements may be fast or slow, upward or downward
    • Possible accompanying clinical features
      • Absent spontaneous and doll’s eye or caloric-induced horizontal eye movements
      • Impaired consciousness
      • Absent spontaneous extremity movements
    • Imaging features
      • Brainstem or cerebral lesion
      • Tip: if brain imaging is negative, metabolic or toxic encephalopathy is likely
    • Acquired binocular pendular nystagmus
    • Epileptic nystagmus
    • Upbeat nystagmus
    • Downbeat nystagmus
    • Distinguish ocular bobbing from upbeat and downbeat nystagmus because in ocular bobbing there may be a reversible metabolic encephalopathy
    • Tip: whether the vertical movements are classic or non-classic does not seem to make any difference in the grave nature of this sign
    • Depends on the underlying condition

    Nystagmus-like Oscillations

    Overview Video Convergence Retraction Superior Oblique Myokymia Square Wave Jerks Saccades of Inattention Ocular Flutter and Opsoclonus Volitional Flutter Ocular Dysmetria Ocular Bobbing Ping Pong Gaze Oscillations of Internuclear Ophthalmoplegia Epileptic Oscillations