Continuous electroencephalographic (EEG) monitoring and a detailed interpretation of the data obtained from such monitoring could help doctors classify patients according to their risk of having seizures, according to a study published in the medical journal JAMA Neurology. This knowledge could help them make better clinical decisions such as treating those at higher risk of seizures with more aggressive treatment approaches.In order to identify the specific characteristics of periodic and rhythmic EEG patterns they may be associated with an increased risk of seizures, Dr Andres Rodriguez Ruiz, of Emory University School of Medicine, and colleagues, reviewed EEG recordings from 4772 critically ill adults. The recordings were taken at Brigham and Women’s Hospital, Yale University Hospital, and Emory University Hospital between February 2013 and September 2015 and corresponded to 5742 sessions averaging 12 hours each. Epileptic seizures occurred during 719 sessions and in 530 of these (74%) periodic/rhythmic patterns were also recorded. The researchers analysed the EEGs in detail looking for different patterns of electrical activity called lateralized periodic discharges (LPDs), lateralized rhythmic delta activity (LRDA), generalized periodic discharges (GPDs), bilateral periodic independent discharges (BIPDs), and generalized rhythmic delta activity (GRDA).The results showed that more LPDs and GPDs were associated with an increased risk of developing seizures. LPDs had the highest association with seizures regardless of their frequency, while LRDAs and GPDs were associated with seizures in a frequency-dependent manner. Finally, the researchers found that patients who had GRDA patterns were not any more likely to have seizures than those with no rhythmic/periodic patterns of activity recorded on the EEG.According to the authors, “These findings highlight the importance of detailed electroencephalographic interpretation” to group patients according to their risk of developing seizures “and clinical decision making”. They also point to the importance of using a standardized terminology to describe the specific patterns recorded during the EEG.Continuous EEG monitoring is a powerful technique, which is increasingly being used to monitor brain activity in order to clearly diagnose and detect non-convulsive epileptic seizures with great sensitivity.Author: Dr Özge ÖzkayaClick here for more articles about brain science including genetics.