Arterial Spin Labeling Magnetic Resonance Imaging in the Assessment of Non-Convulsive Status Epilepticus in Alzheimer's Disease: A Report of Two Cases.

BACKGROUND The diagnosis of early non-convulsant status epilepticus (NCSE) can be challenging and can overlap with other critical conditions. Two patients with Alzheimer's disease are reported with clinically suspected NCSE presenting in the emergency setting who were diagnosed using arterial spin-labeling magnetic resonance imaging (ASL-MRI) sequences. CASE REPORT In Case 1, a 69-year-old woman with mild Alzheimer's disease and diabetes presented with acute worsening of cognitive status and fluctuating level of consciousness. In Case 2, a 70-year-old man with mild cognitive impairment due to Alzheimer's disease and hypertension presented with acute loss of consciousness and left hemiparesis, without evidence of hypoglycemia or a hypertensive crisis. In both cases, ASL-MRI perfusion images showed focal cerebral hyperperfusion in the posterior cingulate and parietal associative cortex, which involved neurodegenerative areas associated with epilepsy in early Alzheimer's disease. In both cases, the patients developed generalized tonic-clonic epileptic seizures that lasted for 5 minutes or more, which indicated the emergence of status epilepticus that developed from the initial presentation of NCSE. In both cases, electroencephalogram (EEG) findings confirmed that the seizures were controlled by intravenous administration of antiepileptic drugs. Both patients discharged home from the hospital without recurrence of seizures, between 10-12 days after the onset of symptoms. CONCLUSIONS These two cases have demonstrated that ASL-MRI is feasible as an emergency diagnostic tool in clinically suspected NCSE in patients with Alzheimer's disease.