P04-F Automatic estimation of the posterior dominant rhythm on a large dataset

Abstract

Background The posterior dominant rhythm (PDR) is an important aspect of the normal EEG. It is a symmetrical rhythm that attenuates in amplitude upon eye opening. Pundergoes maturation, increasing from childhood years until on average 10 Hz. Slowing of the Pcan be a marker of brain disease. We intend to replicate findings of Pmaturation by age on a large dataset using an automated method of Pestimation. Material and methods 16533 EEGs from patients referred for an EEG between 2006 and 2018 in Region Zealand (DK) were used. Only standard EEGs were used, thus acute exams and long term EEG monitoring was excluded. If more than one EEG was obtained from the same patient, only the first one was used. An algorithm selects a suitable part from the beginning of the EEG and calculate the power spectral difference between eyes-open and eyes-closed conditions. The frequency of the most reactive peak between the conditions was taken as the Pestimate. Results We have replicated the trajectory of Pchange by age in a data set significantly larger than any previous reports. Pmatures from childhood until the teenage years and then there is a gradual decline on the population level. Conclusions The Pcan be automatically estimated with good frequency resolution. Fast and objective Pestimation with high frequency precision could make it easier to identify pathological slowing earlier.