The etiologies and clinical features of progressive hydrocephalus in 107 children, 56 with and 51 without shunts, were analyzed retrospectively at the Department of Neurology, Royal Hospital for Sick Children, Edinburgh, Scotland. Patients with arrested hydrocephalus, or with ventriculomegaly resulting from atrophic or ischemic brain damage or tumor were excluded. Intracranial pressure was measured percutaneously or through ventriculostomy reservoirs, using a Gaeltec miniature strain gauge transducer. Etiologies included spina bifida (54%), idiopathic (15%), hemorrhage (13%), and meningitis (10%). In those with malfunctioning shunts, symptoms were vomiting, drowsiness, headache, behavioral change, and anorexia; and signs were absent in 25% and included decreased level of consciousness in 18%, acute strabismus (18%), neck retraction (11%), and distended retinal veins (11%). Patients without shunts were asymptomatic in 49%; headache occurred in 33%, and vomiting in 16%. Signs in the nonshunted group included abnormal head growth in 76%, tense fontanelle (65%), scalp vein distention (33%), setting sun sign or absent upward gaze (22%), and neck rigidity (14%). Unusual clinical features included neurogenic pulmonary edema, profuse sweating, macular rash, ptosis, autonomic dysfunction, and neurogenic stridor. Papilledema occurred in only eight cases (8%). The authors emphasize the variability, unreliability, unusual nature, and even absence of clinical symptoms and signs of hydrocephalus with raised intracranial pressure. CT or MRI may not be diagnostic, and direct measurement of intracranial pressure is essential in patients with unexplained clinical features. 
COMMENT. The infant referred because of a large head is a fairly common problem in pediatric neurology practice. This instructive article points out that we may be relying too frequently on our colleagues in neuroradiology for diagnostic help and neglecting the much simpler and more economical method of direct measurement of intracranial pressure. The finding that one-half the infantile cases of hydrocephalus were without symptoms is disturbing.