Ventricular differences between hydrostatic hydrocephalus and hydrocephalus ex vacuo by computed tomography

Abstract

Transaxial CT scans of 100 patients with hydrostatic hydrocephalus and 50 patients with hydrocephalus ex vacuo have been reviewed with respect to measurements of: frontal horn ratio, width of the temporal horns, width of the third ventricle, width of cerebral fissures and sulci. The diagnosis of hydrostatic hydrocephalus is probable when (a) both temporal tips are visualized and measure 2 mm or greater in width and the sylvian and interhemispheric fissures and cerebral sulci are not visible, or (b) there is visualization of temporal horn tips measuring 2 mm or greater in width and the lateral ventricles are symmetrically enlarged with the frontal horn ratio 0.50 or more.

Diagnosis and Differential Diagnosis of Hydrocephalus in Adults

“…Even though there are no standard values for this in the literature, a diameter of > 2 mm in adults is considered pathological (▶ Fig. 1) [13]. Moreover, the width of the third ventricle increases so that it is no longer slit-shaped but rather ballooned or laterally bowed.…”

Development of Chronic Hydrocephalus and Early Cranial CT Findings in Spontaneous Intracerebral/Intraventricular Hemorrhage

“…Diagnosis was established by early cranial CT scanning. Hydrocephalus was diagnosed if IVH in ICH was present together with at least one of the following radiological criteria [2,8,11,15,25,26]: Clotted/dilated IV th ventricle, dilatation ("ballooning") of III rdventricle, dilatation of temporal horns of lateral ventricles, flattening of cerebral sulci, transependymal paraventricular exsudation of CSF ("capping"). These parameters were added to a semiquantitative CSF circulation impairment score (range 1-5) which could be used for statistical purposes.…”

Applications of Neuroimaging in Hydrocephalus

“…2A. B) [37][38][39][40][41][42][43][44][45] and enlargement o f the anterior and posterior recesses o f the third ventricle [2,18] ( fig. 2A, C, 3).…”

“…72], The reason for the discrepancy in ventricular enlargement between the tem poral lobe and the frontal, parietal and occipital lobes is not fully understood; however, the rather small size of the temporal lobes and, in particular, the relatively small vol ume of white matter in the temporal lobes may play a role [45]. The reason for the disproportionate enlargement of the recesses of the third ventricle is presumably the simple fact that no brain tissue borders the ventricle at those regions, diminishing the resistance to ventricular expan sion under conditions of increased intraventricular pres sure.…”

“…This concentric enlargement of the frontal horns also causes enlargement of the so-called frontal horn radius ( fig. 1) which is determined by mea suring the widest diameter of the frontal horns taken at a 90° angle to the long axis of the frontal horn [37], The final indicator of hydrocephalus is enlargement of the ventricular system to a degree that is disproportionate to the enlargement o f the cortical sulci [45], The theory behind this parameter is that increasing pressure within the ventricular system causes compression of the brain tissue against the inner table of the skull and consequent diminution of sulcal size. In pediatric patients, however, this parameter is often misleading because either atro phy or hvdrocepalus can enlarge both the ventricles and sulci [28], Further complicating the radiologic assess ment is the fact that the size of the ventricles and sub arachnoid spaces is quite variable over the first 2 years of life [43].…”