Ventricular Anatomy
Overview
There are four ventricles within the brain that contain cerebrospinal fluid. There are 2 paired lateral ventricle, a single midline 3rd ventricle and a single midline 4th ventricle. The lateral and third ventricles are connected via the foramen of Monroe. The cerebral aqueduct connects the 3rd ventricle with the 4th ventricle.
Lateral Ventricles
Third Ventricles
Cerebral Aqueduct
Fourth Ventricle
Where is CSF produced and absorbed?
CSF is produced by the choroid plexus that primarily resides within the lateral ventricles. CSF passes from the lateral to the third, from the third to the fourth and subsequently into the subarachnoid spaces filling the sulci and bathing the spinal cord. CSF is then reabsorbed into the venous system by the arachnoid granulations.
Reference 1
Hydrocephalus
If there is an obstruction to CSF flow or abnormal CSF reabsorption, patients may have hydrocephalus and present with symptoms of increased intracranial pressure.
If the abnormality is due to a mass lesion that causes obstruction, this will produce "obstructive" or "non-communicating hydrocephalus" at the site of obstruction.
If the abnormality is due to a process that impairs CSF reabsorption, this produces a "non-obstructive" or "communicating hydrocephalus".
This patient had a mass in the cerebellum, which caused compression of the 4th ventricle, resulting in obstructive hydrocephalus
This patient had a history of trauma with subarachnoid hemorrhage resulting in a communicating, non obstructive hydrocephalus. Notice the enlarged lateral ventricles and the right frontal approach shunt catheter extending into the right lateral ventricle.
Additional Resources
Click HERE to scroll through PPT show on ventricular anatomy.
References
1. http://academic.kellogg.edu/herbrandsonc/bio201_mckinley/Nervous%20System.htm