Setting Sun Sign
The setting sun sign, or sunset sign, consists of tonic downward deviation of the eyes with retraction of the upper eyelids exposing the sclera. There may be downbeating nystagmus. Setting sun sign is a sign of dorsal midbrain compression in children with untreated hydrocephalus.
A similar appearance may also be observed in progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome; Stellwag’s sign) and in Parinaud’s syndrome, but without the tonic downward deviation.