Effect of Ventricular Size on Intellectual Development in Children with Myelomeningocele

Since hydrocephalus is considered to have an unfavorable effect on the intelligence of children with myelomeningocele, we examined the relationship between intelligence quotient (IQ) and ventricular size. Between 1970 and 1989, 130 myelodysplastic infants were admitted to our hospital. Of these infants, 125 received back closure operations, hydrocephalus was observed in 112 (86%), and 94 (72%) were shunted. These 130 infants were followed-up until May 1990. By this time, 9 children were lost to follow-up and 34 children had died. Of the remaining 87 children, those who were 5 years of age or older were the subjects of this study. Ventricular size was graded by Evans’ ratio on initial (preshunting) computed tomography (CT) and follow-up CT. IQ was assessed using the Tanaka-Binet test. Both IQ and initial CT were available in 32 patients, and both IQ and follow-up CT were obtained in 55 children. There seemed to be an inverse relationship between IQ and ventricular size on the initial CT in the neonatal period, but there was no correlation between IQ and ventricular size on the follow-up CT. Considering these results, prompt shunting might not be necessary for some myelodysplastic infants with mild to moderate ventriculomegaly.