Abstracts

RATIONALE: The issue whether hippocampal sclerosis is the cause or consequence of repeated seizure activity remains uncertain. Prospective MRI examination in patients with long-lasting status epilepticus might help to elucidate the spatial and regional progression of seizure-associated brain damage. METHODS: We report a 28 year old afore healthy patient, who presented with drug resistent GTCS-SE (status epilepticus). Pharmacological treatment included intravenous benzodiazepines, phenytoin, valproate,all barbiturates, lidocaine, propofol, ketamine chloride, clomethiazol, and oral lamotrigine, carbamazepine, topiramate. EEG-long-term monitoring did not detect focal seizure origin. The patient died 5 months later due to systemic complications including pancytopenia without evidence for the pathogenesis of the epilepsy. Four series of MRI scans were performed during clinical treatment and neuropathological examination of the brain was available post mortem. RESULTS:Initial MRI scans of the brain revealed no pathological abnormalities. Serial control MRIs (4, 10 and 16 weeks) demonstrated -beside increasing atrophy of infra- and supratentorial structures - T2-weighted hyperintensive signal changes in basal ganglia and hippocampus of both hemispheres. Neuropathological examination revealed widespread neuronal cell loss and astrogliosis within the neocortex, basal ganglia, cerebellum and hippocampus (HC). Both HC were affected: the pyramidal cell layer of CA1 and CA4 was particularly compromized. The latter changes resembled an early stage of Ammonshorn sclerosis as visible in chronic TLE. No specific etiological abnormalities were found. CONCLUSIONS: The described subsequent MRI-and neuropathological findings are compatible with secondary hypoxic-ischemic brain damage following intractable SE, affecting the most vulnerable areas such as HC, basal ganglia and cerebellum. We further suggest that hippocampal sclerosis, i.e. segmental pyramidal cell loss in CA1 and CA4 may result in some instances as consequence rather than being associated with the etiology of severe seizure activity.