To the Editor.
—Duane's retraction syndrome (DRS) is a spectrum of ocular motility anomalies characterized by limitation of horizontal ductions, globe retraction, and narrowing of the palpebral fissure.1 An anatomic basis has been elucidated for some cases, and includes hypoplasia of the abducens nucleus or nerve and ipsilateral anomalous innervation of the lateral rectus by the oculomotor nerve. The cause has remained obscure because the syndrome's varied presentation can be isolated and sporadic, familial, teratogenic, related to birth trauma, or associated with other congenital anomalies and syndromes.Studies of twins can provide insight into the importance of a genetic factor in disease, but there are surprisingly few reports of twins with DRS. Herein we describe a set of monozygotic twins discordant for DRS.
Report of Cases.
—Patient 1 was a 3-year-old boy with a left face turn and an inability to abduct the left eye since birth (Figs 1
Kaufman LW, Folk ER, Miller MT. Monozygotic Twins Discordant for Duane's Retraction Syndrome. Arch Ophthalmol. 1989;107(3):324-325. doi:10.1001/archopht.1989.01070010334014