Objective quantification of seizure frequency and treatment success via long-term outpatient video-EEG monitoring: A feasibility study

A reliable method for the estimation of seizure frequency and severity is indispensable in assessing the efficacy of drug treatment in epilepsies. These quantities are usually deduced from subjective patient reports, which may cause considerable problems due to insufficient or false descriptions of seizures and their frequency. We present data from two difficult-to-treat patients with intractable epilepsy. Pat. 1 has had an unknown number of CP seizures. Here, a prolonged outpatient video-EEG monitoring over 160 h and 137 h (over an interval of three months) was performed with an automated seizure detection method. Pat. 2 suffered exclusively from nocturnal seizures originating from the frontal lobe. In this case, an objective quantification of the efficacy of drug treatment over a time period of 22 weeks was established. For the reliable quantification of seizures, a prolonged outpatient video/video-EEG monitoring was appended after a short-term inpatient monitoring period. Patient 1: The seizure detection algorithm was capable of detecting 10 out of 11 seizures. The number of false-positive events was <0.03/h. It was clearly demonstrated that the patient showed more seizures than originally reported. Patient 2: The add-on medication of lacosamide led to a significant reduction in seizure frequency and to a marked decrease in the mean duration of seizures. The severity of seizures was reduced from numerous hypermotoric seizures to few mild, head-turning seizures. Outpatient monitoring may be helpful to guide treatment for severe epilepsies and offers the possibility to more reliably quantify the efficacy of treatment in the long-term, even over several months.