New-Onset Headache and Abnormal Eye Movements in a Four-Year-Old Child: Indicators of Increased Intracranial Pressure.

A four-year-old previously healthy child presented with new-onset, diffuse, severe headache, and left sixth nerve palsy. The child was evaluated at several acute care facilities, at which the symptom of "crossing eyes" was not addressed specifically. At our emergency department, on day 6 of symptoms, a left cranial nerve 6 palsy was diagnosed; on brain MRI scan, there was evidence of increased intracranial pressure (distended optic nerve sheaths, flattened posterior sclerae), which was confirmed by lumbar puncture, which showed an opening pressure of >36 cm H2O. Idiopathic intracranial hypertension (IIH) was diagnosed, and all symptoms abated with two months of treatment with acetazolamide. IIH should be considered in a child with headache and abnormal eye movements.