Nokea
A 5-day-old infant male has an abnormally large head. A CT scan examination reveals enlarged lateral and third ventricles but a normal-size fourth ventricle. Which of the following conditions is likely to cause this presentation?
Correct Answer: C
Rationale: The correct answer is C: Stenosis of aqueduct of Sylvia. This condition causes obstruction in the Sylvian aqueduct, leading to hydrocephalus with enlarged lateral and third ventricles but a normal fourth ventricle. Holoprosencephaly (A) is a midline defect, not specific to ventricle enlargement. Disorder of prosencephalon (B) is too broad and doesn't specifically address ventricle enlargement. Meningitis with blockage of arachnoid villi (D) is typically associated with communicating hydrocephalus, not specific to the aqueductal stenosis pattern seen in this case.