Fourth ventricular ependymoma in a child with Duane retraction syndrome.

A child with unilateral Duane retraction syndrome developed signs and symptoms of increased intracranial pressure at 3 1/2 years of age. Neuroimaging disclosed a fourth ventricular ependymoma compressing but not invading the floor of the fourth ventricle. The coexistence of Duane syndrome and fourth ventricular ependymoma in a young child raises the possibility that both conditions could have resulted from a mutational event or focus of cellular disorganization (i.e. field defect) localized to the dorsal pons.