Beyond video-EEG: identifying functional/dissociative seizures through clinical assessment.

AIM OF THE STUDY: This study compared the clinical features of functional/dissociative seizures (FDS) and epileptic seizures using video-EEG.

CLINICAL RATIONALE FOR THE STUDY: Early identification of functional/dissociative seizures based on clinical semiology.

MATERIAL AND

METHODS

Seizure semiology was retrospectively analyzed in 51 FDS and 51 age- and sex-matched epilepsy patients. All diagnoses were confirmed by video-EEG. Evaluated features included sustained eye closure, side-to-side head movements, pelvic thrusting, opisthotonus, side-to-side body movements, grimacing, fluctuating course, limb tremors, vocalization, awareness, and seizure duration.

RESULTS

Functional/dissociative seizures patients more frequently exhibited sustained eye closure (90.2% vs. 31.4%), pelvic thrusting (43.1% vs. 5.9%), opisthotonus (27.5% vs. 0%), fluctuating course (66.7% vs. 21.6%), and limb tremors (76.5% vs. 39.2%) compared with epilepsy patients (all p < 0.001). FDS episodes were longer (median 180 s vs. 66 s, p < 0.001). Logistic regression identified sustained eye closure (OR: 56.9), pelvic thrusting (OR: 8.1), and seizure duration (OR: 1.011 per second) as independent predictors of FDS. Significant co-occurrences included opisthotonus with pelvic thrusting and grimacing, fluctuating course with tremor, and side-to-side body movement with head movement and pelvic thrusting.

CONCLUSIONS AND CLINICAL IMPLICATIONS: Sustained eye closure, pelvic thrusting, and prolonged duration are key indicators of FDS. Recognizing these signs can improve diagnostic accuracy when video-EEG is unavailable, prevent unnecessary antiseizure treatment, and facilitate timely psychological care, enhancing overall patient management.