Diagnostic criteria and assessment of the condition in surgically arrested hydrocephalus.

Abstract

Many investigators differ in opinion regarding the clinical concept and accurate criteria for the definition of surgically arrested hydrocephalus. We have studied the diagnostic criteria and various conditions of arrested hydrocephalus through the investigation of a series of 67 patients treated by shunting operation for progressive hydrocephalus. Of these, shunts were removed in 14 cases and these patients had no need for further treatment. We made investigations using neurological, morphological, neuroradiological and psychological methods, CSF dynamic studies including radioisotope cisternography and intraventricular CSF pressure measurements, and biochemical study of fatty acid in CSF. On neurological examination, squint, poor vision and motor weakness were noted in the arrested stage in a few cases. Six patients were educable but slightly retarded, while two were imbeciles. Seven patients (50 %) presented no obvious physical handicaps, however, five were slightly handicapped. Intelligence developed and the degree of physical disability gradually diminished with increasing age. Physical handicaps and residual neurological signs were correlated with the etiology of hydrocephalus. After the shunting operation head circumference remained unchanged for a period and then gradually increased within normal developmental range. Thickness of the cerebral mantle increased from 8 to 30 mm in six cases of congenital hydrocephalus. Usually, cases where thickness of the cerebral mantle were less than 14 mm within 3 months after birth, the subject had a tendency to show poor prognosis. In the arrested stage, the CSF pulse waves consisted of multiphasic components, mean intraventricular CSF pressure was found to be constant by long-term monitoring, and various RI-cisternographic patterns were observed. Three cases showed transient ventricular reflux with early clearance and convexity flow. However, in another 11 cases changes in RI-cisternographic patterns were inconsistent. Examination of fatty acid metabolism in CSF revealed that the total value of fatty acid was closest to normal range after the operation. Arrested hydrocephalus proved to exist in varying degrees as the causes of hydrocephalus vary. Studies from various points of view provided valuable data as to the analysis of arrested hydrocephalus. Diagnosis of arrested hydrocephalus cannot be made on the basis of only simple examination, but should be made by collective judgement from the results of various examinations.