Diagnostic utility of specific abnormal EEG patterns in children for determining epilepsy phenotype and presence of
Mohammed Ashour1,2, Erica Minato3,4, Abdulla Alawadhi1,5,6,7
1Division of Child Neurology, Department of Pediatrics, Montreal Children's Hospital, McGill University, 1001 Décarie Blvd, Montreal, Quebec H4A 3J1, Canada.
Insights
Electroencephalogram (EEG) findings like centrotemporal spikes and photoparoxysmal response have varying diagnostic utility for epilepsy phenotypes. Asymmetric sleep spindles show higher sensitivity and specificity for identifying structural brain abnormalities compared to asymmetric photic driving.
Area of Science:
- Neuroscience
- Clinical Neurology
- Diagnostic Imaging
Background:
- Electroencephalogram (EEG) is crucial for diagnosing epilepsy.
- Specific EEG findings are associated with different epilepsy types and brain abnormalities.
- Understanding the diagnostic accuracy of these findings is essential for clinical decision-making.
Purpose of the Study:
- To estimate the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of key EEG findings.
- To evaluate the diagnostic utility of centrotemporal spikes, photoparoxysmal response, asymmetric photic driving, and asymmetric sleep spindles.
- To correlate these EEG patterns with specific epilepsy phenotypes and the presence of structural brain abnormalities.
Main Methods:
- A case-control study reviewed children with specific EEG findings over a 4-year period.
- The cohort included patients with centrotemporal spikes, photoparoxysmal response, asymmetric photic driving, or asymmetric sleep spindles.
- Data were analyzed in conjunction with a research database of pediatric epilepsy patients.
Main Results:
- Centrotemporal spikes demonstrated 100% sensitivity for specific childhood epilepsy types but lower specificity (70%) and PPV (58%).
- Photoparoxysmal response showed high specificity (92%) and NPV (92%) for genetic generalized epilepsy.
- Asymmetric sleep spindles exhibited higher sensitivity (44%) and specificity (97%) for structural brain abnormalities compared to asymmetric photic driving (17% sensitivity, 80% specificity).
Conclusions:
- While centrotemporal spikes are linked to specific epilepsy syndromes, they appear in other conditions.
- Photoparoxysmal response strongly suggests genetic generalized epilepsy but can occur in other phenotypes.
- Asymmetric sleep spindle attenuation is a more reliable indicator of structural brain malformations than asymmetric photic driving.
Objective:
Estimate sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of EEG findings: centrotemporal spikes, photoparoxysmal response, asymmetric photic driving, and asymmetric sleep spindles, for epilepsy phenotype and presence of structural brain abnormalities.
Methods:
In this case-control study we reviewed children referred for EEG over a 4-year period, with at least one of centrotemporal spikes, photoparoxysmal response, asymmetric photic driving, or asymmetric sleep spindles. This cohort was analyzed in combination with a research database of pediatric patients with seizures.
Results:
Centrotemporal spikes had 100% sensitivity for childhood epilepsy with centrotemporal spikes or atypical childhood epilepsy with centrotemporal spikes, but lower specificity (70%) and PPV (58%). Photoparoxysmal response had high specificity (92%) and NPV (92%) for genetic generalized epilepsy. Asymmetric photic driving had low sensitivity for structural brain abnormalities (17%), with specificity 80%. In contrast, asymmetric sleep spindles had much higher sensitivity and specificity, 44% and 97%, respectively.
Conclusions:
Although centrotemporal spikes are classically associated with childhood epilepsy with centrotemporal spikes, these discharges are seen in other conditions. Photoparoxysmal response is highly indicative of a genetic generalized epilepsy, though may be seen in other epilepsy phenotypes. Relative attenuation of sleep spindles is a more reliable indicator of structural brain malformation than asymmetric photic driving.
Significance:
The quantitative diagnostic utility of EEG findings should be considered when incorporating these results into clinical decision-making.
