Brain oxygen saturation assessment in neonates using T₂-prepared blood imaging of oxygen saturation and near-infrared spectroscopy

Abstract

Although near-infrared spectroscopy is increasingly being used to monitor cerebral oxygenation in neonates, it has a limited penetration depth. The T 2 -prepared Blood Imaging of Oxygen Saturation (T 2 -BIOS) magnetic resonance sequence provides an oxygen saturation estimate on a voxel-by-voxel basis, without needing a respiratory calibration experiment. In 15 neonates, oxygen saturation measured by T 2 -prepared blood imaging of oxygen saturation and nearinfrared spectroscopy were compared. In addition, these measures were compared to cerebral blood flow and venous oxygen saturation in the sagittal sinus. A strong linear relation was found between the oxygen saturation measured by magnetic resonance imaging and the oxygen saturation measured by near-infrared spectroscopy (R 2 ¼ 0.64, p < 0.001). Strong linear correlations were found between near-infrared spectroscopy oxygen saturation, and magnetic resonance imaging measures of frontal cerebral blood flow, whole brain cerebral blood flow and venous oxygen saturation in the sagittal sinus (R 2 ¼ 0.71, 0.50, 0.65; p < 0.01). The oxygen saturation obtained by T 2 -prepared blood imaging of oxygen saturation correlated with venous oxygen saturation in the sagittal sinus (R 2 ¼ 0.49, p ¼ 0.023), but no significant correlations could be demonstrated with frontal and whole brain cerebral blood flow. These results suggest that measuring oxygen saturation by T 2 -prepared blood imaging of oxygen saturation is feasible, even in neonates. Strong correlations between the various methods work as a cross validation for near-infrared spectroscopy and T 2 -prepared blood imaging of oxygen saturation, confirming the validity of using of these techniques for determining cerebral oxygenation.

Monitoring cerebral oxygenation of the immature brain: a neuroprotective strategy?

“…[1][2][3] A recent study showed that NIRS-derived regional cerebral saturation (rScO 2 ; %), which is a mixture of venous (∼75%), capillary (∼5%), and arterial saturation (∼20%), correlates well with magnetic resonance imaging (MRI)determined cerebral oxygenation. 4 Further, combining NIRSmonitored rScO 2 with simultaneous mean arterial pressure can be used as a clinical tool to assess and trend cerebral autoregulation in both premature and term neonates. 5,6 A recent multicenter interventional study, the SafeboosC Study, demonstrated that cerebral oxygenation was quite stable and mostly within the expected reference ranges (55-85%) in 166 extremely preterm neonates during the first 72 h of postnatal life when rScO 2 was monitored.…”

Simultaneous Near-Infrared Spectroscopy (NIRS) and Amplitude-Integrated Electroencephalography (aEEG): Dual Use of Brain Monitoring Techniques Improves Our Understanding of Physiology

“…Near infrared spectroscopy (NIRS) is a non-invasive tool to continuously measure regional tissue oxygenation at the bedside. It can be useful in critically ill neonates as a trend monitor to evaluate the balance between tissue oxygen delivery and consumption, providing cerebral and somatic oximetry values, and allowing earlier identification of hemodynamic changes and brain perfusion abnormalities (1,2). Sensor placement on the forehead easily allows for measurement of regional cerebral oxygen saturation (rScO 2 ) and values have been validated with jugular venous saturations in neonates (3,4).…”

“…In addition, brief or low amplitude seizures may be difficult to identify on the compressed tracing. Newer aEEG devices have seizure detection software, which may facilitate seizure detection (2,9). The use of two channel EEG has improved seizure detection accuracy, and persistent pathological background activity has been associated with poor neurodevelopmental outcome in infants with hypoxicischemic encephalopathy (HIE) and in the preterm population (9,10).…”

T2-prepared velocity selective labelling: A novel idea for full-brain mapping of oxygen saturation

“…While S v O 2 is ideal for true OEF estimation, the QUIXOTIC uses a limited blood pool and suffers from low SNR. The low SNR, in particular a concern in paediatric populations, can be improved by including the entire cerebral blood pool as in the recently proposed "T 2 -prepared Blood Imaging of Oxygen Saturation" (T 2 -BIOS) approach (Alderliesten et al, 2016;Petersen et al, 2012). The T 2 -BIOS sequence measures pure blood T 2 (T 2b ) on a voxel-by-voxel basis.…”

“…Previous work, including our own, demonstrate that oxygen metabolism related parameters have relatively low regional variability throughout the brain. (Alderliesten et al, 2016;J. B.…”