Circadian and ultradian patterns of epileptiform discharges differ by seizure-onset location during long-term ambulatory intracranial monitoring.

OBJECTIVE: Previous studies reporting circadian patterns of epileptiform activity and seizures are limited by (1) short-term recording in an epilepsy monitoring unit (EMU) with altered antiepileptic drugs (AEDs) and sleep, or (2) subjective seizure diary reports. We studied circadian patterns using long-term ambulatory intracranial recordings captured by the NeuroPace RNS System. METHODS: Retrospective study of RNS System trial participants with stable detection parameters over a continuous 84-day period. We analyzed all detections and long device-detected epileptiform events (long episodes) and defined a subset of subjects in whom long episodes represented electrographic seizures (LE-SZ). Spectrum resampling determined the dominant frequency periodicity and cosinor analysis identified significant circadian peaks in detected activity. Chi-square analysis was used to compare subjects grouped by region of seizure onset. RESULTS: In the 134 subjects, detections showed a strongly circadian and uniform pattern irrespective of region of onset that peaked during normal sleep hours. In contrast, long episodes and LE-SZ patterns varied by region. Neocortical regions had a monophasic, nocturnally dominant rhythm, whereas limbic regions showed a more complex pattern and diurnal peak. Rhythms in some individual limbic subjects were best fit by a dual oscillator (circadian + ultradian) model. SIGNIFICANCE: Epileptiform activity has a strong 24 h periodicity with peak nocturnal occurrence. Limbic and neocortical epilepsy show divergent circadian influences. These findings confirm that circadian patterns of epileptiform activity vary by seizure-onset zone, with implications for treatment and safety, including SUDEP.

A flexible postoperative debriefing process can effectively provide formative resident feedback.

BACKGROUND: Providing residents with formative operative feedback is one of the ongoing challenges in modern surgical education. This is highlighted by the recent American Board of Surgery requirement for formal operative assessments. A flexible and adaptable procedure feedback process may allow attending surgeons to provide qualitative and quantitative feedback to residents while encouraging surgeons-in-training to critically reflect on their own performance. STUDY DESIGN: We designed and implemented a flexible feedback process in which residents initiated a postoperative feedback discussion and completed a Procedure Feedback Form (PFF) with their supervising attending surgeon. Comparisons were made between the quantitative and qualitative assessments of attending and resident surgeons. Free text statements describing strengths and weaknesses were analyzed using grounded theory with constant comparison. RESULTS: We identified 346 assessments of 48 surgery residents performing 38 different cases. There was good inter-rater reliability between resident and attending surgeons' quantitative assessment, Goodman and Kruskal gamma > 0.65. Key themes identified on qualitative analysis included flow, technique, synthesis/decision, outcomes, knowledge, and communication/attitudes. Subthematic analysis demonstrated that our novel debriefing procedure was easily adaptable to a wide variety of clinical settings and grew more individualized for senior learners. CONCLUSIONS: This procedure feedback process is easily adaptable to a wide variety of cases and supports resident self-reflection. The process grows in nuance and complexity with the learner and may serve as a guide for a flexible and widely applicable postoperative feedback process.