Presentation
Worsening gait and incontinence
Patient Data
MRI demonstrates marked ventriculomegaly with sulci at the vertex being somewhat smaller than elsewhere without, however, disproportionate widening of the Sylvian fissures of insular cisterns. There is moderate ballooning of the third ventricular recesses (infundibular and supraoptic).
The aqueduct of Sylvius is large and demonstrates a very prominent flow void, although this is an unreliable feature, depending on many sequences specific parameters.
The fourth ventricle communicates freely with an enlarged CSF filled space below and behind the vermis, which is somewhat elevated.
Case Discussion
The features in this cases are consistent with a communicating hydrocephalus. The main differential is between normal pressure hydrocephalus, especially in the context of the prominent aqueductal flow void (an unreliable feature) and the given clinical history.
There is, however, no enlargement of the Sylvian fissures or insular cisterns, an important feature of normal pressure hydrocephalus, which casts some doubt on the diagnosis.
Additionally the infravermian CSF space is enlarged and the vermis somewhat distorted. This raises the possibility of a Blake's pouch cyst.
Higher-resolution imaging through the posterior fossa and CSF flow studies may be of benefit in clarifying the diagnosis.