RESUMO
INTRODUCTION: Third nerve palsy in infancy and early childhood is rare. We present 5 children with isolated monocular oculomotor palsy originally believed to be idiopathic but subsequently documented to be secondary to a presumed neuroma of the third nerve, distal to the mesencephalon. METHODS: Retrospective case review of patient charts from 1995 through 1999 was performed. RESULTS: Mean age at initial presentation was 14.4 months (range, 2-36 months). Two patients were male. Initial manifestation was an incomplete paresis in all 5 cases; 2 patients presented initially with exotropia, 2 with ptosis, and 3 with anisocoria. The pupil was ultimately involved in all cases. Progression to total paresis occurred in 4 of 5 patients over a mean of 13 months (range, 4-22 months). Findings of initial neuroimaging were believed to be normal in all cases but further thin-section gadolinium-enhanced magnetic resonance imaging studies, including coronal views, revealed enlargement and/or enhancement of the subarachnoid or intracavernous portion of the oculomotor nerve. Aberrant regeneration did not develop in any case throughout follow-up (mean, 49.4 months). Visual acuity was decreased on the ipsilateral side in all cases, consistent with amblyopia. No patient had neurofibromatosis. CONCLUSIONS: Suspicion for neuroma should be high in infants and young children with acquired, isolated, apparently idiopathic third nerve palsy. Serial gadolinium-enhanced, 1- to 2-mm thin-section magnetic resonance imaging with coronal views is essential for proper diagnosis.