"Paradoxical" herniation after decompressive trephining

A 50-year-old woman presented with progressive visual disturbance, ataxia, and dementia. The cerebral cortex became atrophic, as the disease progressed, and electroencephalography showed periodic synchronous discharges. The patient's prion gene revealed a point mutation (232Met to Arg), and a diagnosis of Creutzfeldt-Jakob disease was made. Iomazenil single-photon emission computed tomography (SPECT) was performed to assess neuronal degeneration. Accumulation of the tracer in the late images was severely decreased diffusely spread throughout the cerebral cortex. Our experience with this case suggests that iomazenil SPECT is useful for detecting neuronal degeneration in Creutzfeldt-Jakob disease.