Focal cortical hypermetabolism in atypical benign rolandic epilepsy

Area of Science:

• Pediatric Neurology
• Epileptology
• Neuroimaging

Background:

• Atypical benign rolandic epilepsy (BRE) is an underrecognized focal epileptic syndrome.
• It is characterized by centrotemporal spikes and negative motor seizures, potentially impacting speech and cognition.
• The underlying pathophysiology of atypical BRE remains poorly understood.

Purpose of the Study:

• To investigate the spatial and temporal relationship between focal cortical hypermetabolism and centrotemporal spikes in children with atypical BRE.
• To explore the potential link between localized brain activity and clinical manifestations.

Main Methods:

• Utilized electroencephalography (EEG), magnetic resonance imaging (MRI), and positron emission tomography (PET) in three children with atypical BRE.
• Determined the frequency and source localization of centrotemporal spikes.
• Compared spike localization with areas of maximal metabolic activity identified on PET scans.

Main Results:

• Observed overlapping focal cortical hypermetabolism on PET and centrotemporal spike reconstructions in the central sulcus region (within 2 cm).
• Confirmed that hypermetabolism was not caused by recent seizures or frequent spikes during FDG uptake.
• Demonstrated a clear spatial correlation between abnormal brain metabolism and EEG findings.

Conclusions:

• Findings suggest localized increased cortical activity in the EEG focus region is associated with negative clinical features of atypical BRE.
• This localized hypermetabolism may represent the neural substrate of the observed symptoms.
• The results align with findings in other epileptic encephalopathies, such as electrical status epilepticus in sleep.