The role of neuroimaging in the evaluation process of children with isolated sixth nerve palsy

Abstract

The purpose of this study was to assess the role of neuroimaging in identifying the etiology of pediatric isolated sixth nerve palsy (SNP). A retrospective cohort study was conducted of all patients younger than 18years of age with an isolated SNP seen at our medical center between 2003 and 2011. Sixteen children (nine girls; mean age, 4.5years) with isolated SNP were identified during an 8-year period. Only cases with normal optic disk appearance and otherwise normal neurological examination were included into this study. Thus, 12 other children with SNP were excluded: ten children with papilledema, one child who developed a SNP following a resection of a brain tumor, and one with hydrocephalus and a shunt malfunction. All cases of isolated SNP were unilateral (ten left eyes). The most common cause for the SNP in these children was a tumor that was found in five patients. Other etiologies encountered in decreasing frequencies were: benign recurrent SNP (in four children), postviral or vaccination (in three children), and one case each of post trauma, Chiari malformation, congenital, and undetermined. Children who were found to have a tumor (9.9 ± 5.5years) were significantly older (P = 0.019) than children who did not have a tumor (2.1 ± 1.8years). Isolated SNP can be the presentation of a brain tumor in children, and therefore, early neuroimaging of the brain is recommended, especially in older children.