Table 3.

Clinical data extracted from the included articles.

Findings	Pre-Ictal, Ictal, or Post-Ictal Data	NIRS Biomarkers	NIRS Device, Sensor Positioning	Type of EEG Monitoring Used	Treatments Used	Underlying Pathology in Neonate(s)	Participants (Number with NIRS Data, Median Gestational Age, Species)	Study Design	First Author, Year
During each event, HbO2, HHb and HbT increased to a maximum. They then rapidly decreased to a minimum before slowly returning to baseline values. HHb changes were generally not significant.	Post-ictal	HbO2, HHb, HbT	UCL Diffuse Optical Tomography, Cap	Full EEG-OT with clinical, 9-electrode EEG montage or reduced-electrode EEG	Phenobarbital, phenytoin, clonazepam and midazolam infusion.	Severe neonatal HIE following right temporal haemorrhagic stroke, Left middle and posterior cerebral artery infarct, suspected sepsis at birth, hypoglycaemia.	4 40 weeks Human	Cohort Study	Cooper et al., 2011 [74]
Rhythmic rSO2 fluctuations occurred during each seizure. Within each episode, rSO2 levels initially decreased, followed by a sharp increase and a slow decrease toward baseline. Baseline rSO2 levels increased with each subsequent seizure.	Pre-ictal, ictal, and post-ictal	rSO2	-	aEEG	Therapeutic hypothermia, midazolam, phenobarbital, and phenytoin	HIE	1 35 weeks Human	Case Report	Martini et al., 2019 [75]
Regardless of outcome, rSO2 values during seizures trended towards being significantly higher than periods without seizures (85% vs. 81%, p= 0.0534).	Ictal	rSO2	INVOS, Left or right side of the forehead	vEEG	Therapeutic hypothermia	HIE	1 38 weeks Human	Case Report	Pacella et al., 2020 [76]
At the start of each seizure, CCO increased. Following the aEEG peak, CCO fell to below baseline levels, leading to a progressively lower baseline with each subsequent seizure. HbT and HbD both decreased initially and then slowly returned to baseline after the aEEG peak.	Ictal, post-ictal	CCO, HbT, HbD, HbO2, HHb	Broadband NIRS, Both sides of the forehead, using an optode distance of 2.5 cm	10-channel neonatal EEG (Nicolet EEG monitor), aEEG trends were derived	Therapeutic hypothermia, phenobarbitone, ionotropic support	HIE	1 38 weeks Human	Case Report	Mitra et al., 2016 [46]
During the post-ictal period, synchronous and repeater transiter changes were noted in HbO2, HHb and CCO in both hemispheres. The parameters acutely dropped before a slow increase toward baseline. This pattern of changes occurred in 16 separate events.	Post-ictal	CCO, HbT, HbD, HbO2, HHb	Broadband NIRS One NIRS channel was placed on either side of the forehead. Four detected optodes were placed horizontally against each source optode with source-detector distances of 1.0, 1.5, 2.0 and 2.5 cm.	Nicolet EEG monitor	Phenobarbitone, phenytoin, midazolam, paraldehyde	Neonatal Stroke	1 40 weeks Human	Case Report	Mitra et al., 2016 [77]
Every seizure lasting longer than 100 s occurred as rSO2 levels were rising and was associated with a drop in rSO2 levels.	Ictal	rSO2	INVOS 5100, Light sources placed 2 cm above the eyebrows and 2 cm from the midline on the right and left sides of the forehead. Detectors were placed at the same level in front of the ears.	vEEG	Phenobarbital, fosphenytoin	Tuberous sclerosis	1 38 weeks Human	Cohort Study	Shuhaiber et al., 2004 [78]
rSO2 changes occurred in 7 out of 8 seizures that lasted 7 min or longer. 4 out of 5 seizures that lasted less than 7 min were not associated with any rSO2 changes.	Ictal	rSO2	NIRO 200, Right frontal parietal region and covered with light-proof cloth.	Two-channel aEEG with electrodes at F3-P3, F4-P4 positions	Therapeutic hypothermia, phenobarbitone, phenytoin and midazolam infusion	HIE	1 39 weeks Human	Cohort Study	Silas et al., 2012 [79]
30 s prior to seizure onset, an increase in HHb, HbO2 and HbT was observed. After reaching a maximum, all three parameters decreased until they reached a minimum. Concentrations then began to recover toward baseline levels.	Pre-ictal, ictal, and post-ictal	HHb, HbT, HbO2	UCL Diffuse Optical Tomography, Cap	aEEG, Dot-EEG with flexible head cap	Therapeutic hypothermia, phenobarbital, clonazepam, and phenytoin.	Severe HIE	1 40 weeks Human	Case Report	Singh et al., 2014 [43]
Prior to electrographic onset, an increase in HbO2, HHb and HbT was observed to a maximum level. All three parameters began to decrease prior to electrographic offset. The extended decrease occurred, and parameters recovered to baseline values.	Pre-ictal, ictal, and post-ictal	HbO2, HHb, HbT	UCL Diffuse Optical Tomography, Cap	DOT-EEG (standard 11-channel EEG neonatal montage)	Therapeutic hypothermia,	Severe HIE	1 40 weeks Human	Case Report	Singh et al., 2016 [80]
rSO2 levels declined during seizures in both hemispheres. FTOE increased during seizures.	Ictal	rSO2, FTOE	CYtochrome Research Instrument and appLication (CYRIL), Both sides of the forehead, using an optode distance of 2.5 cm	vEEG	Phenobarbital	HIE, neonatal epilepsy syndromes, arterial ischaemic stroke, sepsis, benign neonatal seizures, sinovenous thrombosis, intracranial haemorrhage, and uncertain	20 39 weeks Human	Cohort Study	Sokoloff et al., 2015 [81]
Seizures exhibited biphasic changes. HHb initially increased, then decreased, which was associated with an increase in HbO2 and HbT. During seizures, rSO2 always decreased slightly.	Pre-ictal, ictal	HbO2, HHb, HbT, rSO2, FTOE	Imagent from ISS, Cap	High-resolution direct-current (HR DC) EEG and Alternating-current electroencephalography (AC EEG) with electrode cap	Phenobarbital	Acute foetal distress resulting in caesarean section	1 40 weeks Human	Case Report	Wallois et al., 2009 [82]