A 6-month old previously healthy infant boy presented with 1.5 weeks of intermittent esotropia (alternating and bilateral), vertical gaze palsy with lid retraction (parinaud syndrome), truncal tone changes, and head/neck bobbing. He was born full term with no significant birth complications. He was developmentally appropriate without evidence of developmental regression. His head circumference was 45cm at the 75th percentile for age with a soft anterior fontanelle. His examination was significant for described eye movements above, head lag, and possible reduced use of the right hand, confounded by an IV in that hand, normal reflexes. He had no pertinent recent travel history, sick contacts, or ill symptoms. CT head demonstrated evidence of obstructive hydrocephalus and MRI demonstrated an enhancing pontine mass, found to be consistent with atypical teratoid rhabdoid tumor (ATRT).
