Cerebrospinal fluid edema: a rare complication of shunt operations for hydrocephalus. Report of three cases.

Three cases are presented in which a rare complication occurred after a shunt operation for hydrocephalus. On postoperative computerized tomography (CT) scans, extensive low-density areas appeared in the white matter along the ventricular catheter. After shunt revision, gradual resolution or disappearance of the low-density area was clearly demonstrated on CT. In one patient, a collection of cerebrospinal fluid (CSF) was confirmed at operation and appeared to lie in the extracellular spaces of the white matter. The phenomenon is considered to be localized CSF edema, different from porencephaly.