Characteristics of MEG positive occipital sharp transients of sleep in normal people: a simultaneous MEG⁃EEG study

Abstract

Objective To preliminarily explore the correlation of positive occipital sharp transients of sleep (POSTS) in MEG and EEG, and summarize the characteristics of MEG POSTS morphology and localization. Methods The MEG and EEG signals were simultaneously recorded in 5 healthy subjects during sleep, who were recruited from December 2020 to August 2021 in Beijing Tiantan Hospital, Capital Medical University. The features of MEG POSTS and its relationship with EEG POSTS were summarized. Single equivalent current dipole (ECD) model was used to conduct source imaging for POSTS. Results About 564 EEG POSTS during sleep were recorded in 5 subjects. There were 359 simultaneous MEG POSTS in occipital region after exclusion of the POSTS overlapping with heart beat in ECG. The appearance rate of MEG POSTS was 73.42% (359/489). The MEG POSTS showed great variability in morphology. MEG POSTS dipoles were located mainly in bilateral midline regions of occipital lobe, including calcarine sulcus, lingual gyrus and cuneus; some in other parts of occipital lobe away from midline regions, such as medial occipitotemporal gyrus, lateral occipitotemporal gyrus and lateral occipital cortices; and a small portion in bilateral parietooccipital sulcus and precuneus. Conclusions MEG POSTS has characteristics different from EEG POSTS, so it is important to recognize POSTS correctly in clinical MEG reading to discriminate between physiological and pathological waves and provide precise information for presurgical evaluation of epilepsy.

Keywords

• positive occipital sharp transients of sleep (not in mesh)
• magnetoencephalography
• electroencephalography
• adult