Initial experience of a telemetry EEG amplifier (Headset™) in the emergent diagnosis of nonconvulsive status epilepticus

Abstract

Objectives: In the diagnosis of nonconvulsive status epilepticus (NCSE), the use of ongoing ictal electroencephalographic (EEG) findings is the gold standard. However, this is difficult without the availability of continuous EEG monitoring facilities. Given this, a small telemetry EEG amplifier (Headset-EEG; AE-120A EEG Headset™) was introduced for use in simple EEG monitoring facilities. In this study, we examined the diagnostic performance of the Headset-EEG for NCSE in a neuroemergency setting.Methods: We retrospectively selected five patients who were diagnosed with NCSE using Headset-EEG by attending physicians between October 2017 and July 2018. Reevaluation with Headset-EEG was performed, and the findings were compared with the initial diagnosis. Results: In Case 1, Headset-EEG clearly revealed repeated ictal discharges associated with acute subdural hematoma. However, in Cases 2 and 3, the initial EEG diagnosis was incorrectly made because of an EEG interpretation error. In Cases 4 and 5, various artifacts, caused by unstable electrode placement, resulted in an initial diagnosis of ongoing seizure activity. Nevertheless, the initial diagnoses and subsequent treatment of Cases 2–5 did not directly affect the patients' outcomes.Conclusion: The present study indicates that Headset-EEG is a possible tool for use in NCSE screening. However, considerable knowledge of EEG interpretation is needed to establish a correct NCSE diagnosis. When NCSE is suspected per Headset-EEG, a subsequent routine EEG with a full montage of 10–20 EEG electrodes should be performed in collaboration with an epileptologist or electroencephalographer. Keywords: Triphasic waves, Metabolic encephalopathy, Artifact