Congenital ocular motor apraxia associated with myopathy, external hydrocephalus and NADH dehydrogenase deficiency.

Congenital ocular motor apraxia (COMA), first described by Cogan [Trans Am Acad Ophthalmol Otolaryngol 1952;56:853-862], is a rare disorder characterized by impairment of voluntary and optically induced horizontal eye movements and compensatory head thrust. The causes and pathogenesis of COMA are poorly understood. It frequently occurs in association with other neurologic abnormalities including non-progressive congenital disorders of the central nervous system (CNS), various systemic diseases and chromosomal alterations. Here, we report the case of a 6-month-old girl with psychomotor retardation, myopathy and clinical features of COMA, associated with external hydrocephalus and mitochondrial dysfunction (partial deficiency of the respiratory-chain enzyme NADH dehydrogenase). In view of this finding, we recommend that tests to characterize patients with COMA should include determination of blood levels of lactic and pyruvic acid.