Case 5: Discussion

Communicating vs non-communicating hydrocephalus?

This is an example of non-communicating hydrocephalus (obstructive hydrocephalus) related to a mecahncical obstruction by the mass at the level of the fourth ventricle.

• Non-Communicating:
  • - Obstructive hydrocephalus
  • - Mechanical block to CSF flow, typically caused by masses
  • - The ventricles that are enlarged depend on the site of obstruction
• Communicating:
  • - Impaired resorption of CSF at the level of the arachnoid granulations
  • - Caused by any process that plugs up arachnoid granulation such as subarachnoid hemorrhage or infection.
  • - Expect all of the ventricles to be enlarged to the same degree.