Walsh & Hoyt: Eye Movements in Stupor and Coma

The ocular motor examination is especially useful for evaluating the unconscious patient, because both arousal and eye movements are controlled by neurons in the brain stem reticular formation. Comatose patients do not make eye movements that depend upon cortical visual processing. Voluntary saccades and smooth pursuit are in abeyance, and quick phases of nystagmus also may be absent. The ocular motor examination of the unconscious patient, therefore, consists of observing the resting position of the eyes, looking for any spontaneous movements, and reflexively inducing eye movements. Gaze deviations.