Saccades

Saccades: instruct the patient to make rapid movements of their eyes in each gaze direction, noting the speed, conjugacy, latency, and accuracy. First have the patient look between an eccentric target and the camera horizontally and vertically, making assessment of accuracy easier - e.g., overshooting the camera (hypermetria) or undershooting the camera (hypometria). Then have the patient make larger amplitude saccades horizontally and vertically, which makes assessment of speed and conjugacy easier (e.g., adduction lag suggests an internuclear ophthalmoplegia [INO], https://collections.lib.utah.edu/details?id=187742). Saccadic dysmetria is seen in cerebellar disease (or brainstem connections w/ cerebellum [https://collections.lib.utah.edu/details?id=187722&q=saccadic+dysmetria&fd=title_t%2Cdescription_t%2Csubject_t&facet_setname_s=ehsl_novel_gold]). Ipsilateral hypermetria and contralateral hypometria occurs in Wallenberg syndrome (https://collections.lib.utah.edu/details?id=187724). Slow saccades of restricted amplitude occur in motor nerve paresis or muscle weakness.