Magnetic resonance imaging of unusual intracranial infections.

We review the etiologic agents, epidemiology, pathogenesis, pathology, clinical manifestations, and imaging features of several unusual intracranial infections that have not been discussed elsewhere in this issue. The central nervous system (CNS) infections discussed are Creutzfeldt-Jakob disease (CrJaD), neurosyphilis, primary amebic meningoencephalitis (PAM), granulomatous amebic encephalitis (GAE), cerebral amebiasis, and cerebral hydatid disease.