Abstracts

Rationale: Diagnostic delay in distinguishing psychogenic nonepileptic seizures (PNES) from epileptic seizures may result in unnecessary therapeutic interventions and health care costs. Effective PNES screening tools can potentially mitigate diagnostic delay. Previous studies demonstrated that ictal eye closure during video-EEG monitoring can serve as a reliable indicator of PNES. The present study assessed whether observer or self-report of eye closure could be used to predict PNES, prior to video-EEG monitoring. Methods: Adult epilepsy monitoring unit subjects were prospectively enrolled into the study. Self-report of eye closure was assessed using a written questionnaire, and observer report was obtained by interview. Blinded physicians determined the incidence of video-captured eye closure during PNES and epileptic seizures. Random effects models evaluated whether video-captured eye closure predicted an episode as PNES, while accounting for episode clustering by subject. The utility of observer and self-report of eye closure in predicting a diagnosis of PNES was tested using logistic regression and 2x2 tables.Results: Of 132 consecutively enrolled subjects 112 met study criteria during EMU stay for either PNES (n=43, 38.4%) or epilepsy (n=84, 75.0%). Affirmative self and observer reports of eye closure were neither sensitive nor specific for the diagnosis of PNES. Of note, the odds ratio for PNES episode classification by video-captured eye closure decreased from 9.2 (95% CI, 5.5 – 15.2) for subjects with four or more episodes to 0.8 (95% CI, 0.3 – 2.5) for those with three or fewer. Conclusions: Neither observer nor self report of eye closure, prior to VEEG monitoring, predicts PNES. Video-captured eye closure accurately predicts PNES only when four or more episodes are recorded.