Diagnosis and management after nondiagnostic EMU admissions: short-term follow-up study.

OBJECTIVE: Capturing a habitual event is often required to determine the etiology of events during video-EEG (vEEG) monitoring. vEEG studies that fail to capture a habitual event are typically considered non-diagnostic. In this study, we evaluated the clinical impact of non-diagnostic vEEG studies.

METHODS: We identified non-diagnostic vEEG studies from a cohort of epilepsy monitoring unit (EMU) admissions. Patients were followed longitudinally in the outpatient clinic.Clinical impact was assessed by evaluating changes in diagnosis and antiseizure medication (ASM) management at EMU discharge and at the last clinic follow-up.

RESULTS: Patients were categorized according to referral indication: (I) spell clarification in individuals with paroxysmal events (n = 10); (II) event differentiation in patients with epilepsy (n = 16); (III) reassessment of a prior epilepsy diagnosis (n = 20); and (IV) classification of seizure or epilepsy type (n = 18). Following EMU admission, one patient in Group I was diagnosed with seizures, while the prior epilepsy diagnosis was withdrawn in eight patients in Group III. At EMU discharge, ASM reduction was most frequent in Group III (11/20), whereas ASM escalation was most common in Group II (7/16). By the last clinic follow-up, two additional patients had been diagnosed with seizures. Further ASM escalation occurred in 14 patients: two in Group I, three in Group II, three in Group III, and six in Group IV.

SIGNIFICANCE: Non-diagnostic vEEG studies can still provide meaningful diagnostic insight. Subsequent management strategies varied substantially depending on the indications for EMU admission and the clinical context.