Which condition most directly results from impaired CSF absorption?

• A. Hydrocephalus due to CSF buildup
• B. Increased absorption
• C. No effect
• D. Venous outflow increased

Answer: (A)

When CSF absorption is impaired, fluid produced by the choroid plexus accumulates because it isn’t cleared efficiently into the venous system. The result is buildup of CSF in the ventricles and subarachnoid space, expanding the ventricular system and raising intracranial pressure—that’s hydrocephalus. This scenario is typically called communicating hydrocephalus, where the flow of CSF is not blocked within the ventricles, but its absorption into the dural venous system is reduced.

The other options don’t fit the mechanism: absorption would not increase, so that option isn’t correct; there would be a measurable effect on CSF dynamics, not none; and venous outflow would not be increased as a direct consequence of impaired CSF absorption.