Duane retraction syndrome associated with Chiari I malformation

A 13-year-old girl who had Duane retraction syndrome associated with Chiari I malformation is reported. Neuro-ophthalmologic examination revealed severe limitation of abduction of the left eye, as well as narrowing of the palpebral fissure and retraction of the globe on adduction. Electro-oculography of the affected eye revealed decreased saccadic velocity on attempted abduction and adduction. Midsagittal magnetic resonance imaging demonstrated cerebellar tonsillar herniation to 6 mm below a line from the basion to opisthion. Taking into consideration the relative rarity of the two disorders, the association may not be coincidental. Magnetic resonance imaging of the posterior fossa is recommended in Duane retraction syndrome.