The Application of Density Spectral Array Monitoring in Digital Electroencephalography for Levetiracetam-Induced Non-Convulsive Status Epilepticus in a Patient with Lennox-Gastaut Syndrome

Objective: To analyze the density spectral array (DSA) on the digital electroencephalography (EEG) in a patient with Lennox-Gastaut syndrome (LGS) who developed non-convulsive status epilepticus (NCSE) after initiation of oral levetiracetam (LEV). Methods: Digital EEG was performed on the patient for a 30 min period during the daytime while he was asleep status without hypnotic drugs. The DSA, which incorporated a conventional program of the digital EEG, was sequentially evaluated. Result: The DSA demonstrated that the continuous and periodic high voltages and broad ranges of oscillation, reflecting epileptic activity and the clinical conditions. The EEG demonstrated obvious bilateral frontopolar and/or diffuses 2-3 Hz slow spike-and-wave complex activities, which were not evident before initiation of LEV. Development of LEV-induced NCSE was suspected. Discontinuation of LEV and increasing the dose of clobazam resulted in recovery from NCSE, followed by gradual restoration of the original DSA and EEG findings. Conclusion: On administering of LEV for patients with LGS, the occurrence of NCSE should be carefully monitored. The DSA based on digital EEG was useful for both the diagnosis of NCSE as a drug side-effect and the recovery from its epileptic status.