Hydrocephalus and school-age neurodevelopmental outcomes in the management of myelomeningocele prenatal surgery trial: a secondary analysis.

OBJECTIVE: The purpose of this secondary analysis was to assess the role of hydrocephalus on neurodevelopmental outcomes in a cohort of school-age children enrolled in the Management of Myelomeningocele Study (MOMS) clinical trial. METHODS: The sample analyzed in this report consisted of 150 of 183 children aged 5-10 years (mean ± SD 7 years 8 months ± 1.2) who were randomly assigned between 20 and 26 weeks of gestational age to undergo either prenatal or postnatal surgery and were enrolled in the school-age follow-up study of MOMS. These 150 children (76 prenatal and 74 postnatal) were placed into three groups: no hydrocephalus (n = 22), unshunted hydrocephalus (n = 31), and shunted hydrocephalus (n = 97). Comparisons were made on the basis of measures of adaptive behavior, intelligence, reading and math skills, verbal and nonverbal memory, fine motor dexterity, and sensorimotor skills. Parent ratings of executive functions, inattention, and hyperactivity-impulsivity were also compared. RESULTS: There were no statistically significant differences in neurodevelopmental outcomes between the groups with no hydrocephalus and unshunted hydrocephalus, or between the prenatal and postnatal groups with shunted hydrocephalus, so these groups were combined (no/unshunted vs shunted hydrocephalus). The no/unshunted group showed significantly better performance (p < 0.05) than the shunted group in terms of adaptive behavior, intelligence, verbal and nonverbal memory, reading skills (but not math), fine motor dexterity, sensorimotor skills (but not visual-motor integration), and inattention (but not hyperactivity-impulsivity or executive function ratings). An assessment of the prenatal surgery group showed that the combined no/unshunted group performed better than the shunted group in terms of adaptive behavior and verbal memory skills. Both the prenatal and postnatal surgery subgroups with unshunted hydrocephalus performed as well as the group with no hydrocephalus despite significantly enlarged ventricles. CONCLUSIONS: Although the primary assessment of school-age outcomes in the MOMS clinical trial did not show better adaptive behavior and cognitive skills in the prenatal group, hydrocephalus and shunting were associated with poorer neurodevelopmental outcomes (both prenatal and postnatal groups). Disease severity and dynamic changes in hydrocephalus status may be the primary factors in the need for shunting and a major determinant of adaptive behavior and cognitive outcomes after prenatal surgery.