Pseudohydrocephalus-Megalocephaly, Increased Intracranial Pressure and Widened Subarachnoid Space

Abstract

Seven children with rapid enlargement of the head and other clinical features resembling hydrocephalus are described. All children remained with relatively large heads, developed slowly and all but one had various degrees of mental and motor handicaps. The EEG was disturbed in all cases; two children developed seizures. Increased intracranial pressure was present. In all patients the subarachnoid space was markedly widened while the ventricular system was normal or minimally dilated. The characteristics of this syndrome, the features distinguishing it from similar conditions as well as its possible mechanism are discussed.

Effect of Temporary Subdural-Peritoneal Shunt on Subdural Effusion with Subarachnoid Effusion

“…It has been recently reported by Robertson et al [15] and others [9] that the subdural effusion with such CT findings disappeared without any treat- [Mori et al, 1981: Robertson andGomez 1978]: Pseudohydrocephalus-megalocephaly [Sahar 1978]; external hydrocephalus [Robertson and Gomez, 1978]: extraventricular obstructed hydrocephalus [Pettit et al. 1080]. mcnt, and there remained no neurological deficiency by aging.…”

External hydrocephalus: radiologic spectrum and differentiation from cerebral atrophy

“…Nonetheless, the condition remains poorly understood and is still frequently unrecognized or misdiagnosed. The multiple terms used to describe external hydrocephalus, such as "pseudohydrocephalus-megalocephaly" [4], "benign subdural collections of infancy" [6], and "extraventricular obstructive hydrocephalus" [7] demonstrate the confusion that has surrounded the entity. The difficulty with diagnosing and recognizing EH is due in part to the frequency with which it is associated with other conditions, such as prematurity [9, 1 1 ], subdural hematomas [6,10], intraventricular hemorrhages [9], and genetic syndromes [2, 1 3].…”

Pediatric MRI Brain: Normal or abnormal, that is the question.

“…The ventricles may be normal in size or mildly enlarged [26]. The increase in head circumference frequently occurs around the age of 6 months [27] and stabilizes at around 18 months [28,29,30]. It is often challenging for the reporting radiologist to define the limit between normal and enlarged subarachnoid spaces.…”