Table 1.

Summary of brain imaging techniques and their application in SOZ identification for adults and children.

Imaging technique	Invasive/non-invasive	Number of imaging sessions	Spatial resolution	Temporal resolution	Brain area	SOZ ID in adults with DRE	SOZ ID in children with DRE
PET	Invasive	1	6 mm	5 mins	Surface	Identified in 66.7% of subjects (Mayoral et al., 2019)	Only detects EN in 6.6% of patients and not SOZ (Bansal et al., 2016)
Ictal SPECT	Invasive	2, needs difference between ictal and inter-ictal SPECT (Desai et al., 2013)	6 mm	15 mins	Surface	Detects EN and not SOZ (Kaiboriboon et al., 2002; von Oertzen, 2018)	Detects EN and not SOZ (Van Paesschen et al., 2007)
MEG	Non-invasive	1	10–20 mm	<10 ms	Cortex	75% accurate (Foley et al., 2021) in eight patients, 60% with ML in a large cohort (Nissen et al., 2018)	Poor concordance with SOZ. Identified onset zone is >20 mm distance from ground truth SOZ (Ntolkeras et al., 2022)
iEEG (gold standard)	Invasive	Long-term monitoring (14 days)	6–8 cm	<5 ms	Cortex	92.3% accurate (Nagahama et al., 2018)	>90% accurate (Nagahama et al., 2018)
fMRI	Non-invasive	1	3 mm	2–5s	Central brain	Sensitivity 83% and specificity 67% (Chen et al., 2017)	89% accurate SOZ identification (Boerwinkle et al., 2019)

PET, positron emission tomography; SPECT, single-photon emission computerized tomography; MEG, magnetoencephalography; iEEG, intracranial electroencephalography; fMRI, functional magnetic resonance imaging.