Aqueduct stenosis due to web

Case contributed by Assoc Prof Frank Gaillard


Long standing ventriculomegaly

Patient Data

Age: 30 years
Gender: Male

Gross enlargement of the lateral and third ventricles, with superior bowing of the markedly thinned corpus callosum. The fourth ventricle is normal in caliber. Centrally, the cerebral aqueduct has a focal membrane/web without any convincing flow on CSF flow studies. 

No evidence of tectal plate mass. The cerebral white matter volumes are diffusely reduced, presumably related to a longstanding hydrocephalus, which is associated with the typical skull findings. No periventricular hyperintensity to suggest transependymal edema. 

Conclusion: Gross hydrocephalus sparing the fourth ventricle due to aqueductal stenosis.


A third ventriculostomy has been performed by a right frontal craniotomy and approach through the right frontal lobe. Surgical tract through the right frontal lobe is surrounded by a tiny amount of blood and there is also a resultant small volume of pneumocephalus. A subtle signal loss demonstrated on high-resolution sagittal FIESTA and flow on phase-contrast flow studies (not shown). Aqueductal web and gross hydrocephalus again shown, ventricular size similar to preop. Resultant thinning of cerebral parenchyma is unchanged from the previous MRI.


Case Discussion

Typical features of aqueduct stenosis due to a web with subsequent third ventriculostomy


PlayAdd to Share

Case information

rID: 42207
Published: 28th Apr 2016
Last edited: 14th Aug 2019
Inclusion in quiz mode: Included

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.