Advanced Deep Learning Spectroscopy of Scalogram Infused CNN Classifiers for Robust Identification of Post-Hypoxic Epileptiform EEG Spikes

There is a lack of reliable prognostic biomarkers for hypoxic-ischemic (HI) brain injury in preterm infants. Herein, spectrally detailed wavelet scalograms (WSs), derived from the 1024Hz sampled electroencephalograms (EEG) of preterm fetal sheep after HI (n=7), are infused into a high-performance deep convolutional neural network (CNN) pattern classifier to identify high-frequency spike transient biomarkers. The deep WS-CNN pattern classifier identifies EEG spikes with remarkable accuracy of 99.81=0.15% (area under curve, AUC=1.000), cross-validated across 5010 EEG waveforms, during the first 6h post-HI (42h total), an important clinical period for diagnosis of HI brain injury. Further, a feature-fusion strategy is introduced to extract the spectrally dominant features of the raw EEG epochs to form robust 3D input matrix sets to be infused into the deep 2D-CNNs for pattern classification. The results show that the proposed WS-CNN approach is less sensitive to the potential morphological variations of spikes across all subjects compared to other deep CNNs and spectral-fuzzy classifiers, allowing the user to flexibly choose an approach depending on their computational requirements. Collectively, the data provide a reliable framework that could help support well-timed diagnosis of at-risk neonates in clinical practice.