20190321_nanos_currentconcepts1_02_slides

Cogan first described this congenital condition which is characterized by an impairment of voluntary, saccadic eye movements in the horizontal direction. Patients with COMA typically present with poor visual responses in early infancy and may appear visually impaired. When head control is established at about 6 months, compensatory horizontal head thrusting movements often develop, seemingly utilizing an exaggerated vestibulo-ocular reflex. The lateral head rotation overshoots the target of regard, with the eyes lagging behind. When the eyes finally 'land' on the visual target the head simultaneously turns back to a normal position with the eyes are in a primary gaze position. Head thrusting is common but not universal. Horizontal slow pursuit ; movements may be normal or partly impaired in COMA patients, and vertical eye movements are usually preserved.