Distinction between epileptic and non-epileptic arousal by heart rate change.

OBJECTIVE: We investigated the difference in heart rate (HR) change between epileptic and non-epileptic arousals in adult patients with epilepsy (PWE). METHODS: This is a case-control study conducted at the University Hospitals of Cleveland Medical Center. Inclusion criteria are (1) adult (≥18 years old) PWE who had arousal related to a focal aware or impaired awareness automatism seizure with or without focal to bilateral tonic-clonic seizure during an Epilepsy Monitoring Unit (EMU) admission between January 2009 and January 2021 or (2) adult PWE who had a non-epileptic arousal during an EMU admission between July 2020 and January 2021. Outcomes are (1) a percent change in baseline HR within 60 s after arousal and (2) the highest percent change in baseline HR within a 10-s sliding time window within 60 s after arousal. RESULTS: We included 20 non-epileptic arousals from 20 adult PWE and 29 epileptic arousals with seizures from 29 adult PWE. Within 60 s after arousal, HR increased by a median of 86.7% (interquartile range (IQR), 52.7%-121.3%) in the epileptic arousal group compared to a median of 26.1% (12.9%-43.3%) in the non-epileptic arousal group (p < 0.001). The cut-off value was 48.7%. The area under the curve (AUC), sensitivity, and specificity were 0.85, 0.79, and 0.80, respectively. More than 70.1% was only in the epileptic arousals, with 100% specificity. Within 10 s of the greatest change, HR increased by 36.5 (18.7%-48.4%) in the epileptic arousal group compared to 17.7 (10.9%-23.7%) in the non-epileptic arousal group (p < 0.001). The cut-off value was 36.5%. The AUC, sensitivity, and specificity were 0.79, 0.52, and 0.95, respectively. More than 48.1% was only in the epileptic arousals, with 100% specificity. SIGNIFICANCE: Tachycardia during epileptic arousals was significantly higher and more robust compared to tachycardia during non-epileptic arousals.

Epileptic negative myoclonus in herpes simplex virus encephalitis.

Epileptic negative myoclonus (ENM) is a rarely reported clinical seizure semiology. It is defined as a brief interruption of tonic muscle activity in association with an epileptiform discharge on the EEG (spike or sharp wave) without preceding myoclonia. The diagnosis of ENM requires a polygraphic recording with EEG and surface EMG electrodes covering the affected body part(s), while the muscles have tonic activity. Historically, ENM has been reported in a variety of chronic epilepsy syndromes such as benign epilepsy with centrotemporal spikes, progressive myoclonic epilepsy syndromes, symptomatic partial epilepsy syndromes due to structural pathologies, cryptogenic epilepsies, etc. In this paper, we report a patient with herpes simplex virus encephalitis who presented with multiple different seizure types including ENM. The patient showed significant improvement after treatment with acyclovir.

Stereotactic-EEG-guided radiofrequency multiple hippocampal transection (SEEG-guided-RF-MHT) for the treatment of mesial temporal lobe epilepsy: a minimally invasive method for diagnosis and treatment.

For the treatment of mesial temporal lobe epilepsy on the language-dominant side in patients at high risk of memory decline, we propose a minimally invasive diagnostic and treatment technique, adopting the principles of multiple hippocampal transections (MHT) using stereo-electroencephalography-guided radiofrequency (SEEG-guided-RF-MHT). This new technique allows targeting of the longitudinal fibers in the hippocampus critical for seizure spreading, while sparing the transverse circuits which are considered important for memory processing and avoiding discomfort and longer post-operatory recovery time associated with craniotomies. We report the efficacy and safety of this procedure in a preliminary observational study of cases. Five patients at high risk of memory decline, including three with non-lesional hippocampi on MRI, had temporal lobe epilepsy (TLE) necessitating depth electrode implantation. A new strategy of SEEG electrode placement was used to mimic MHT. After confirming hippocampal seizure onset, all the patients had three linear ablations perpendicular to the amigdalohippocampal complex. The procedure was performed at the patient's bedside with the patient awake during the full length of the procedure. Four out of five patients were seizure-free (average follow up: 14-18 months). There were no associated complications. Visual inspection of brain MRI of patients at six months following SEEG-guided RF-MHT showed significant hippocampal volume preservation. Subjects who received the procedure in the dominant side reported no subjective memory complaints in the follow-up clinic assessments at six months. Our preliminary seizure outcome seems very promising since the majority of our patients (four out of five patients) were seizure-free. Since no lesions are made outside the amygdalo-hippocampal complex using this technique and the temporal stem remains intact, more favorable memory and language outcome is expected in patients at high risk of memory decline.