Reevaluation of the Electroencephalogram Recordings of Patients With Nonconvulsive Status Epilepticus by Using Salzburg Consensus Criteria

Abstract

Objective: Nonconvulsive status epilepticus (NCSE) is a challenge to diagnose in some cases, and recently, Salzburg consensus criteria for NCSE (SCC-NCSE) were developed to contribute to clinical practice. We aimed to investigate their validity and usefulness by reevaluating the electroencephalogram (EEG) examinations of our patients in this study. Materials and Methods: We retrospectively evaluated all EEG recordings of patients diagnosed with NCSE by experienced clinical neurophysiologists in our EEG laboratory over a period of 2 years. Two neurologists trained in EEG reanalyzed all EEG data and categorized these patients as NCSE, possible NCSE, or non-NCSE using the SCC-NCSE. Results: Twenty-nine patients with a mean age of 31.5 & PLUSMN; 25.9 were reanalyzed. According to the SCC-NCSE, 24 patients (82.7%) were diagnosed as NCSE. Eighteen patients (62%) who fulfilled all SCC-NCSE were diagnosed as NCSE, whereas six patients (20.7%) were diagnosed only as possible NCSE. Five patients (17.3%) did not fulfill SCC-NCSE; the reasons are the lack of additional secondary criteria in 2 patients with encephalopathy, the absence of full compliance with the criteria in other 2 patients, and a diagnosis of electrical status epilepticus during sleep in the last patient. Conclusion: The results of our study show that SCC-NCSE is highly consistent with clinical practice to decide for the diagnosis of NCSE. The evaluation of NCSE according to a set of new standardized criteria is thought to be difficult in practice, but it provides a more objective assessment. Therefore, we believe that its use should be encouraged to increase experience and the possibility of correct diagnosis.