Superficial siderosis of the central nervous system: magnetic resonance imaging and pathological correlation. Case report.

The authors report a 32-year-old woman who had undergone repair of an occipital encephalocele in infancy and who experienced a 20-year history of progressive hearing loss and intermittent vertigo. After parturition, she developed a rapidly progressive quadriparesis and brain-stem dysfunction associated with persistent intraventricular and subarachnoid hemorrhage. Serial magnetic resonance (MR) images showed progressive deposition of hemosiderin along the surface of the brain, brain stem, and spinal cord, and enhanced thickened membranes at the site of the original encephalocele repair. Posterior fossa exploration disclosed hemorrhagic membranes, which were resected; despite removal of this tissue, the patient deteriorated and died. Postmortem examination confirmed iron-containing pigment along the meninges, cerebral hemispheres, brain stem, spinal cord, and cranial nerves accompanied by atrophy of the superficial cerebellar cortex. It is concluded that superficial siderosis may accompany encephalocele repair. This is believed to be the first report in the literature of superficial siderosis of the central nervous system to correlate in vivo MR images with autopsy results.