|
A 2 year-old girl presented with an enlarging head and a delay in motor milestones. |
| Non-Communicating Hydrocephalus:
(Left and Middle) Flair axial MRI scans; (Right) T1-weighted
sagittal MRI scan. Note the prominent enlargement of the
lateral and third ventricles in the setting of a normal sized fourth
ventricle. This pattern is one of non-communicating (obstructive)
hydrocephalus, which occurs from impaired drainage through the
cerebral aqueduct which connects the third and fourth ventricles.
This picture differs from communicating hydrocephalus wherein all
the ventricles are enlarged. Hydrocephalus is recognized as enlarged ventricles out of proportion to the amount of cerebral atrophy. Non-communicating (obstructive) hydrocephalus occurs when the ventricular system is not in continuity with the subarachnoid space. Most often, the site of the blockage in non-communicating hydrocephalus is at the cerebral aqueduct, but rarely can occur at the foramen of Monro, the third ventricle, or the outlet of the fourth ventricle. Acute non-compensated, non-communicating (obstructive) hydrocephalus is a neurosurgical emergency as the non-compensated hydrocephalus results in a progressive increase in intracranial pressure, which if left unchecked will result in herniation and brain death. It is potentially treatable by shunting. |
Revised
11/23/06
Copyrighted 2006. David C Preston