Aug 2026· Frontiers in Neurology· Vol 17· 0 citations· 33 references
Medicine
TL;DR
SCSs are present in approximately one quarter of presurgical epilepsy patients and show moderate concordance with CS and IED localization and their distinct localization profile and frequent containment within CS zones support their value as complementary information in epilepsy care.
Abstract
Purpose Subclinical seizures (SCSs) are commonly detected during video-EEG monitoring but frequently overlooked in clinical practice. Their prevalence, localization characteristics, and relationship to clinical seizures (CSs) and interictal epileptiform discharges (IEDs) remain incompletely defined. This study aimed to characterize SCS prevalence, localization, frequency, and concordance with CS and IED localization in a presurgical epilepsy cohort, and to examine associations between SCS presence and neuropsychological performance. Methods A retrospective observational study was conducted in 116 adult patients undergoing inpatient scalp video-EEG telemetry and neuropsychological evaluation at King’s College Hospital between 2015 and 2023. SCS localization was compared with CS and IED localization using a five-category concordance framework and Cohen’s kappa for lateralization and temporal vs. extratemporal agreement. Results SCSs were present in 26.7% of patients. No clinical or demographic variable was significantly associated with their presence. SCSs most frequently localized to left temporal and right extratemporal regions, whereas CSs were more evenly distributed across temporal foci. Full concordance between CS and SCS localization was observed in 55.2% of co-recorded studies; where incomplete, SCS localizations were more often contained within CS localizations than the reverse. IED localizations were more widespread than both seizure types. Lateralization agreement was moderate across all comparisons (κ = 0.40–0.47). SCS presence was not significantly associated with neuropsychological test scores. Conclusion SCSs are present in approximately one quarter of presurgical epilepsy patients and show moderate concordance with CS and IED localization. Their distinct localization profile and frequent containment within CS zones support their value as complementary information in epilepsy care.
Overall, the presence of SCSs alone was not associated with a poor outcome, but the spatial non-concordance with the seizure-onset zone was highly predictive for poor seizure outcome.
P. Bosque-Varela, Panagiota-Eleni Tsalouchidou, Petra Levicka et al.· Epilepsia· 0 citations
OBJECTIVES
Ambulatory electroencephalography (aEEG) allows prolonged outpatient monitoring and improves seizure detection compared with routine EEG, particularly for subclinical seizures. aEEG is especially valuable in underserved populations, where socioeconomic barriers and comorbidities contribute to delayed diagnosis and poor seizure control. The objective of the study is to evaluate seizure-detection rate with aEEG in an underserved epilepsy population and to examine how it relates to self-reported seizure control. Clinical and socioeconomic factors influencing the discrepancy between actual vs perceived seizure control were examined.
METHODS
This is a retrospective, cross-sectional study of adult patients who underwent aEEG at the University of Illinois Hospital, Chicago, Illinois. Demographic and clinical data (seizure history, medications, aEEG findings, and presence of psychiatric and cognitive comorbidities) were extracted from electronic medical records. Participants were grouped according to the presence or absence of seizures on aEEG. Univariate analyses and multivariate logistic regression were used to identify predictors of seizures detected on aEEG, whereas secondary analyses examined discrepancies between reported seizure frequency and the presence of seizure on aEEG.
RESULTS
Of 382 patients included, seizures were captured on aEEG in 46 patients (12%), the majority of which were subclinical (80%). Patients with seizures on aEEG were more likely to be unemployed or on disability, have focal epilepsy, be prescribed a greater number of anti-seizure medications (ASMs), and have mild cognitive impairment (MCI). In multivariate analysis, number of ASMs (odds ratio [OR] 2.10, 95% confidence interval [CI] 1.44-3.07) and presence of MCI (OR 6.13, 95% CI 3.04-12.38) independently predicted seizures on aEEG. MCI was present in ~70% of patients with subclinical seizures who were reporting rare seizures at home.
SIGNIFICANCE
aEEG detects subclinical seizures that often go unrecognized by patients. The presence of seizures has been shown to be associated with MCI. This highlights the importance of objective monitoring beyond patient self-report, particularly in vulnerable populations.
Julia Bodnya, J. Soble, G. Trifan et al.· Epilepsia· 0 citations
WMH are common in adults with focal epilepsy, and the frontal lobe is the most frequently affected region, and age, seizure duration, interictal epileptiform discharges, and seizure duration are independent risk factors for greater WMH burden.
Xu Zhang, Wenjie Zhang, Chang Ge et al.· Clinical EEG and Neuroscienc...· 0 citations
OBJECTIVE
The postictal state is a major yet underrecognized component of the epilepsy burden. We aimed to develop a structured patient-reported instrument to quantify postictal recovery, characterize its multidimensional burden, and identify demographic, clinical, psychiatric, and treatment-related factors associated with postictal severity and duration.
METHODS
We conducted a prospective, single-center observational cohort study (Timone Hospital, Marseille, February 2025-March 2026). Consecutive patients aged ≥15 years admitted for scalp or stereo-EEG video-monitoring were included. Patients completed the Postictal Recovery Scale (PRS), an 11-domain questionnaire assessing fatigue, mood, sensory, motor, language, orientation, time perception, and postictal amnesia. Items were rated from 0 (severe impairment) to 3 (no symptoms), yielding a total score of 0-33. Internal consistency was assessed using Cronbach's alpha. Associations between PRS scores, subjective postictal duration and covariates were analyzed using group comparisons, correlations, and regression models.
RESULTS
Of 107 enrolled patients, 96 were included. PRS showed good internal consistency (Cronbach's α = 0.79). 96% of patients reported experiencing postictal symptoms, with fatigue (80%) and postictal amnesia (79%) being the most frequent and severe manifestations. Recovery exceeded 1 h in 21% of patients. Greater postictal impairment was associated with higher interictal anxiety (Spearman ρ = -0.32, p = 0.0018) and depressive symptoms (Spearman ρ = -0.40, p = 0.0001), whereas demographic, epilepsy-related, and treatment variables showed no significant associations. Altered postictal time perception was reported by 40% of patients and was associated with disorientation, but not postictal psychiatric symptoms. Subjective postictal duration was longer than subjective ictal duration (Wilcoxon test, p < 0.0001).
SIGNIFICANCE
The postictal state is a frequent and multidimensional patient-reported experience. Greater postictal severity, particularly concerning anxiety and depression, is associated with interictal psychiatric comorbidity, while altered temporal experience emerges as a distinct dimension of postictal dysfunction. These findings support integrating postictal measures into clinical practice and trials.
Ionuț-Flavius Bratu, A. Trébuchon, F. Bartolomei· Epileptic disorders· 0 citations
Overall, Benign epileptiform variants lack pathological significance, although 6-Hz spike-and-wave bursts and small sharp spikes showed a stronger association with epilepsy and may be considered variants of uncertain significance warranting clinical follow-up.
Rosa Ana Saiz Díaz, S. B. Cuéllar, Jesús González de la Aleja Tejera et al.· Neurología· 0 citations
OBJECTIVE
Functional/Dissociative Seizures (FDS), formerly known as psychogenic nonepileptic seizures, are common in tertiary epilepsy centers and remain challenging to distinguish from epileptic seizures. Beyond semiological features, additional behavioral markers such as the presence of transitional objects have been proposed as potential diagnostic clues. This study aimed to assess whether transitional objects and selected clinical semiological features could help differentiate FDS from epileptic seizures during video-electroencephalographic (vEEG) monitoring.
METHODS
We conducted a retrospective cross-sectional study at the Epilepsy Monitoring Unit of the Centre Hospitalier de l'Université de Montréal (CHUM). Adult patients who underwent vEEG monitoring between April 2018 and April 2025 were included. The FDS group comprised patients with at least one recorded FDS, while age- and sex-matched controls consisted of patients with confirmed epileptic seizures and no recorded FDS. Video recordings were systematically reviewed by an epileptologist to assess the presence of transitional objects (e.g., stuffed animals, blankets, pillows, slippers) and predefined semiological features, including pelvic thrusting, ictal eye closure, back arching (opisthotonos), and ictal crying.
RESULTS
A total of 101 patients with FDS (383 events) and 101 patients with epileptic seizures (371 events) were analyzed. Transitional objects were observed in 18 patients with FDS and 16 controls (unadjusted p = 0.177; Holm-Bonferroni-adjusted p = 0.849), with no significant differences between groups. In contrast, pelvic thrusting, ictal eye closure, back arching, and ictal crying were significantly more frequent in the FDS group. Psychiatric comorbidities were also more prevalent among patients with FDS (41 vs. 18, unadjusted p < 0.001; Holm-Bonferroni-adjusted p = 0.003), particularly depression and bipolar disorder.
SIGNIFICANCE
Transitional objects, including stuffed animals, do not appear to be discriminative markers between FDS and epileptic seizures. However, specific semiological features remain useful for positive diagnosis of FDS, in line with current International League Against Epilepsy recommendations. These findings support a clinically driven diagnostic approach based on seizure semiology rather than transitional objects alone.
