Detailed neuropathologic examination was performed on a 47.5-year-old
man with an unusual adult-onset dementing illness. His initial symptom
s were those of depression, memory loss, and personality change. He de
veloped progressive cognitive decline with prominent psychiatric sympt
oms. Seizures began approximately 11 months prior to death and he died
5.5 years after onset of symptoms. Pathologic examination of the brai
n at autopsy revealed organizing necrosis of the hippocampi, felt to b
e the result of his seizures. More significant was the finding of wide
spread microscopic nodular cortical dysplasia. The dysplastic nodules
were composed of clusters of abnormal cells with enlarged, pleomorphic
, vesicular nuclei, many of which contained nucleoli and had ballooned
cytoplasm, There were no mitoses. Cortical dysplasia is most commonly
associated with childhood-onset seizures. It has not, to our knowledg
e, been reported as a cause of dementia. Whether or not the dysplasia
was the basis of the patient's dementia is difficult to say with certa
inty, but we discuss possible pathoetiologic mechanisms of dementia du
e to cortical dysplasia.