Video-EEG monitoring: safety and adverse events in 507 consecutive patients.

PURPOSE: Video-electroencephalography (EEG) monitoring plays a central role in the presurgical evaluation of medically refractory epilepsies and the diagnosis of nonepileptic attack disorders (NEADs). The aim of this study was to analyze safety and adverse events (AEs) during video-EEG monitoring. METHODS: We retrospectively evaluated 596 video-EEG sessions in 507 patients (233 men, mean age 36 years, standard deviation = 14, range 9-80 years) within a 6-year period. AEs were examined in detail and their risk factors were assessed using multiple logistic regression analysis. KEY FINDINGS: Forty-four patients (9%) experienced 53 AEs: 20 had psychiatric events (17 postictal psychosis, 2 panic attacks, 1 interictal psychosis), 15 had injuries (14 falls with minor injuries, 2 falls with fractures, 2 fractures without fall, 1 fall with epidural hematoma), 10 patients had 13 episodes of status epilepticus (SE), and one AE was treatment-related (valproic acid--induced encephalopathy). Patients with AEs were older (p = 0.036) and had a longer duration of epilepsy (p = 0.019). All AEs resulted in a prolonged hospital stay (p < 0.001). Ninety-one percent of the AEs occurred within the first 4 days of monitoring. Independent risk factors were duration of epilepsy >17 years [odds ratio (OR) 3.096; 95% confidence interval (CI) 1.548-6.189], a previous history of psychiatric illness (OR 16.882; 95% CI 5.469-52.110), a history of seizure-related injuries (OR 3.542; 95% CI 1.069-11.739), or a history of SE (OR 3.334; 95% CI 1.297-8.565). SIGNIFICANCE: The most common AEs were postictal psychosis, falls, and SE. Patients with an older age, long disease duration, psychiatric comorbidity, history of injuries, and SE have a higher risk.

Asymmetric seizure termination in primary and secondary generalized tonic-clonic seizures.

PURPOSE: In temporal lobe epilepsies an asymmetric termination (AST) of the clonic phase of secondary generalized tonic-clonic seizures (sGTCS) reliably lateralizes the side of seizure onset. The last clonic activity occurs ipsilateral to the side of the seizure onset zone. We compared the prevalence and lateralizing value of AST in sGTCS of frontal and temporal lobe origin as well as in primary generalized tonic-clonic seizures (pGTCS). METHODS: We analyzed 177 seizures in 84 consecutive patients. Forty-one patients had temporal lobe epilepsy (TLE), 24 frontal lobe epilepsy (FLE), and 19 had nonfocal (primary) generalized epilepsies (GE). All patients underwent intensive video-EEG (electroencephalography) monitoring, high-resolution magnetic resonance imaging (MRI), neuropsychological testing, and single photon emission computed tomography/positron emission tomography (SPECT/PET) when feasible. Two investigators blinded for diagnosis, EEG, and imaging data assessed frequency and side of the last clonic jerk. RESULTS: AST occurred in 63% of patients with TLE (47% of seizures), in 71% with FLE (60% of seizures), and in 42% with GE (21% of seizures). These results were not significant for patients, but significant for seizures in TLE versus GE and in FLE versus GE (p < 0.001). The positive predictive value (PPV) for the side of seizure onset was 74% (p = 0.003) in TLE and 75% (p = 0.008) in FLE. DISCUSSION: AST in sGTCS lateralizes the side of seizure onset in TLE and in FLE to the ipsilateral hemisphere with a high PPV. However, AST was also observed in GE. Therefore, asymmetric clinical signs should not inevitably lead to the assumption of focal epilepsy syndromes.

Myoclonic status epilepticus in juvenile myoclonic epilepsy.

BACKGROUND: Myoclonic status epilepticus (MSE) is rarely found in juvenile myoclonic epilepsy (JME) and its clinical features are not well described. We aimed to analyze MSE incidence, precipitating factors and clinical course by studying patients with JME from a large outpatient epilepsy clinic. METHODS: We retrospectively screened all patients with JME treated at the Department of Neurology, Medical University of Innsbruck, Austria between 1970 and 2007 for a history of MSE. We analyzed age, sex, age at seizure onset, seizure types, EEG, MRI/CT findings and response to antiepileptic drugs. RESULTS: Seven patients (five women, two men; median age at time of MSE 31 years; range 17-73) with MSE out of a total of 247 patients with JME were identified. The median follow-up time was seven years (range 0-35), the incidence was 3.2/1,000 patient years. Median duration of epilepsy before MSE was 26 years (range 10-58). We identified three subtypes: 1) MSE with myoclonic seizures only in two patients, 2) MSE with generalized tonic clonic seizures in three, and 3) generalized tonic clonic seizures with myoclonic absence status in two patients. All patients responded promptly to benzodiazepines. One patient had repeated episodes of MSE. Precipitating events were identified in all but one patient. Drug withdrawal was identified in four patients, one of whom had additional sleep deprivation and alcohol intake. Two patients received inappropriate treatment (carbamazepine, phenytoin). CONCLUSIONS: MSE is a rare event in JME. Precipitating factors are commonly identified and for such cases the treatment response and outcome are excellent, in contrast to other cases with unknown causes.