Evaluation of Patients Monitored in Long-term Video-electroencephalography: Clinical and Demographical Specificities with Management Implications

Objective: Long-term video-electroencephalography monitoring (LTVEM) is an invaluable technique to assess patients with epilepsy, specifically for differential diagnosis and managing drug-resistant epilepsy. LTVEM plays a crucial role in the surgical management of epilepsy. We aimed to determine the clinical and demographic specificity of patients monitored at the LTVEM unit and the optimal length of hospitalization to decide on management. Methods: Demographic data, electrophysiological findings, seizure types, duration, latencies, length of stay, and treatment of 96 consecutive adult patients who were monitored at the LTVEM unit between August 2023 and February 2024 were retrospectively evaluated. Results: We identified 49 (51%) epileptic patients, 34 (35.4%) non-epileptic patients, and 9 (9.4%) patients with coexistence of epilepsy and psychogenic non-epileptic seizure (PNES). The latency of the first PNES attack was shorter than that of the first epileptic attack. The mean seizure duration of patients diagnosed with PNES was longer than that of patients diagnosed with epilepsy. The mean latency time to first interictal epileptiform discharge (IED) in patients with generalized epilepsy was shorter than the mean latency time to first IED in patients with focal epilepsy. The mean length of stay of patients with focal epilepsy was significantly longer than that of patients with generalized epilepsy (p<0.001). Conclusion: One-third of the patients monitored in our LTVEM unit were diagnosed with PNES. The latency of the first seizures of patients diagnosed with PNES was shorter than that of patients diagnosed with epilepsy, whereas the seizure duration of PNES was longer. It has been revealed that the first IED latency in patients with focal-onset seizures, and probably related to this, the length of hospital stay is longer than that in patients with generalized epilepsy. We believe that the current study may be helpful in planning the LTVEM unit hospitalization period and appointments for different types of seizure.