Hamed Azizollahi1, Ardalan Aarabi2,3, Fabrice Wallois1,4. 1. GRAMFC, Inserm U1105, University Research Center (CURS), CHU AMIENS - SITE SUD, Amiens, France. 2. Laboratory of Functional Neuroscience and Pathologies (LNFP), University Research Center (CURS), University Hospital, Amiens, France. 3. Faculty of Medicine, University of Picardy Jules Verne, Amiens, France. 4. Department of Pediatrics, EFSN Pediatric (Pediatric Nervous System Functional Investigation Unit), CHU AMIENS-SITE SUD, Amiens, France.
Abstract
OBJECTIVE: Neonatal electroencephalography (EEG) source localization is highly prone to errors due to head modeling deficiencies. In this study, we investigated the effect of head model complexities on the accuracy of EEG source localization in full term neonates using a realistic volume conductor head model. APPROACH: We performed numerical simulations to investigate source localization errors caused by cerebrospinal fluid (CSF) and fontanel exclusion and gray matter (GM)/white matter (WM) distinction using the finite element method. MAIN RESULTS: Our results showed that the exclusion of CSF from the head model could cause significant localization errors mostly for sources closer to the inner surface of the skull. With a less pronounced effect compared to the CSF exclusion, the discrimination between GM and WM also widely affected all sources, especially those located in deeper structures. The exclusion of the fontanels from the head model led to source localization errors for sources located in areas beneath the fontanels. Our finding clearly shows that the CSF inclusion and GM/WM distinction in EEG inverse modeling can substantially reduce EEG source localization errors. Moreover, fontanels should be included in neonatal head models, particularly in source localization applications, in which sources of interest are located beneath or in vicinity of fontanels. SIGNIFICANCE: Our findings have practical implications for a better understanding of the impact of head model complexities on the accuracy of EEG source localization in neonates.
OBJECTIVE: Neonatal electroencephalography (EEG) source localization is highly prone to errors due to head modeling deficiencies. In this study, we investigated the effect of head model complexities on the accuracy of EEG source localization in full term neonates using a realistic volume conductor head model. APPROACH: We performed numerical simulations to investigate source localization errors caused by cerebrospinal fluid (CSF) and fontanel exclusion and gray matter (GM)/white matter (WM) distinction using the finite element method. MAIN RESULTS: Our results showed that the exclusion of CSF from the head model could cause significant localization errors mostly for sources closer to the inner surface of the skull. With a less pronounced effect compared to the CSF exclusion, the discrimination between GM and WM also widely affected all sources, especially those located in deeper structures. The exclusion of the fontanels from the head model led to source localization errors for sources located in areas beneath the fontanels. Our finding clearly shows that the CSF inclusion and GM/WM distinction in EEG inverse modeling can substantially reduce EEG source localization errors. Moreover, fontanels should be included in neonatal head models, particularly in source localization applications, in which sources of interest are located beneath or in vicinity of fontanels. SIGNIFICANCE: Our findings have practical implications for a better understanding of the impact of head model complexities on the accuracy of EEG source localization in neonates.
Authors: Maria Carla Piastra; Andreas Nüßing; Johannes Vorwerk; Maureen Clerc; Christian Engwer; Carsten H Wolters Journal: Hum Brain Mapp Date: 2020-11-06 Impact factor: 5.399