The learner will better appreciate the large gap between modern theories of hydrocephalus and its common understanding.
We are taught in the major texts as well as in our training that communicating hydrocephalus is the result of an imbalance between CSF production at the choroid plexus and CSF resorption at the arachnoid granulations. This is known as the bulk flow theory which is easy to understand and explain. It is logically consistent and convincingly provides the learner with the illusion of understanding.
Unfortunately, this explanation is inconsistent with many experimental and therapeutic observations. For example, third ventriculostomy is a procedure used to treat communicating hydrocephalus. But this procedure does not improve CSF resorption nor affect CSF production.
We discuss the hydrodynamic theory which is more difficult to explain and understand.but nevertheless more consistent with many of the relevant facts.
Imaging Findings in Hydrocephalus
CSF production, resorption and turnover
Problems with the bulk flow theory
Monroe-Kelly doctrine
Windkessel effect.
Hydrocephalus as a disorder of compliance and hydrodynamic theory
How to explain:
effectiveness of 3rd ventriculostomy
temporal horns first to expand
4th ventricle last to expand
References
Romano, J,
Kobets, A,
Hydrocephalus: Modernity and Mythology. Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL.
http://archive.rsna.org/2014/14018229.html