Aqueduct stenosis with corpus callosum hypoattenuation post shunting

Case contributed by A.Prof Frank Gaillard


Long standing abnormality.

Patient Data

Age: 55 years
Gender: Male

The lateral and third ventricles are moderately dilated and the fourth ventricle appears at least slightly enlarged. The temporal horns are dilated and the floor of the third ventricle is bowed inferiorly. 

The aqueduct is markedly dilated throughout its length but appears focally stenosed at its termination at its junction with the fourth ventricle. Flow studies suggests little if any cerebrospinal fluid flow passing through the aqueduct and T2-weighted scans show no evidence of pulsatility (no flow void) within the third and fourth ventricles, normally expected in communicating / normal pressure hydrocephalus.

Empty sella noted. Corpus callosum is stretched and thinned, but no evidence of interstitial (transependymal) edema. Cortical sulci moderately flattened.


Features are those of a long standing aqueduct stenosis

Non-contrast imaging through the brain has been obtained demonstrating no intra extra-axial collection or mass. The ventricles remain enlarged despite shunt having been inserted. 

Since the previous CT there has been significant reduction in size of the lateral and third ventricles, which are now normal in caliber. This is accompanied by a new hypodensity throughout the body of the corpus callosum. 

No acute intracranial hemorrhage. No extra-axial collection. Old right temporal craniotomy and anterior temporal encephalomalacia.


Reduction in size of the lateral and third ventricles. Hypodensity in the corpus callosum, which is no longer superiorly elevated and compressed against the free edge of the falx.

Case Discussion

Hypodensity of the corpus callosum has been described post shunting, thought to be secondary to chronic compression of the corpus callosum against the falx becoming appreciable once the ventricles have been decompressed in the corpus callosum moves inferiorly. 

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Case information

rID: 37212
Published: 18th Feb 2016
Last edited: 16th Jul 2018
Inclusion in quiz mode: Included

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