Obstruction to the flow of CSF at the aqueduct of Sylvius will most likely lead to the enlargement of all the ventricles (AIIMS Nov 2013)
|A||Only lateral ventricle|
|B||Only third ventricle|
|C||Both lateral and third ventricles|
Both lateral and third ventricles
CSF formation & circulation:CSF is produced predominantly by the choroid plexus of the lateral, followed by third and fourth ventricles.
Flow is caudal through the ventricular system - Lateral ventricles to aqueduct of Sylvius via foramina of Monro. Then it reaches fourth ventricle and move into the subarachnoid space through the foramina of Luschka and Magendie (on the roof of fourth ventricle).