In rare cases, a lesion, usually identified by MRI and confirmed by biopsy, and in some cases by special autoantibodies, takes the form of a chronic focal encephalitis.
In 1958, Rasmussen described three children in whom the clinical problem consisted of intractable focal epilepsy in association with a progressive hemiparesis.
The cerebral cortex disclosed a mild meningeal infiltration of inflammatory cells and an encephalitic process marked by neuronal destruction, gliosis, neuronophagia, some degree of tissue necrosis, and perivascular cuffing. Many additional cases were soon uncovered and Rasmussen was able to summarize the natural history of 48 personally observed patients (see the often cited monograph by Andermann).
Adams & Victor’s Principles of Neurology, 10e
Chapter 16. Epilepsy and Other Seizure Disorders
© 2014 by McGraw-Hill Education.