Acquired hydrocephalus. II. Diagnostic and prognostic value of quantitative isotope ventriculography (QIV), lumbar isotope cisternography (LIC), pneumoencephalography, and continuous intraventricular pressure recording (CIP).

The diagnostic and prognostic values of quantitative isotope ventriculography (QIV), lumbar isotope cisternography (LIC), pneumoencephalography (PEG), and continuous intraventricular pressure recording (CIP) were assessed on the basis of the clinical course in 160 patients suspected of having acquired hydrocephalus. The diagnostic value of a given method is defined as its reliability in the diagnosis of hydrocephalus. The reliability in the selection of hydrocephalic patients who will improve on shunt operation is designated as the prognostic value of the method concerned. As the diagnoses are based on isotopic procedures, the diagnostic values of these procedures cannot be assessed. QIV is of greater prognostic value than the other methods of examination. The presence of plateau waves in CIP is a rare, but prognostically valuable sign. The prognostic value of B waves is also good, whereas their diagnostic value is slight. Both from diagnostic and prognostic points of view, PEG is of less value is communicating hydrocephalus on account of the many false findings.