Cognitive dysfunction with complex visual hallucinations due to focal nonconvulsive status epilepticus: a neuropsychological study and SISCOM.

A 74-year-old woman with left hemiparesis due to a previous stroke presented with the sudden development of cognitive impairment and episodic complex visual hallucinations as manifestations of nonconvulsive status epilepticus (NCSE). Neuropsychological tests performed during NCSE demonstrated deficits encompassing several cognitive domains. The short-lasting complex visual hallucinations were stereotypical, vivid, and accompanied by intense fear. The seizure activity in the right temporo-parieto-occipital region, as documented by SISCOM and electroencephalogram (EEG) recording, was thought to be due to an unusual clinical presentation of NCSE. Subcortical cerebromalacia likely blocked the propagation route, restricting the ictal activities within this area.