Early identification of neonatal mild hypoxic-ischemic encephalopathy by amide proton transfer magnetic resonance imaging: A pilot study

Purpose: This study aimed to evaluate the amide proton transfer (APT) values in neonates with mild hypoxicischemic encephalopathy (HIE) using APT imaging. Method: A total of 30 full-term neonates with mild HIE (16 males and 14 females; mean postnatal age 4.2 days, age range 2-7 days) and 12 normal neonates (six males and six females; mean postnatal age 3.3 days, age range 2-5 days) underwent conventional magnetic resonance imaging and APT imaging. APT measurements were performed in multiple regions of interest (ROIs) in the brain. APT values were statistically analyzed to assess for significant differences between the mild HIE and normal neonates in different regions of the brain, and correlation with neonatal gestational age. Results: In 30 neonates with mild HIE, 10% (3/30) of the HIE patients had normal conventional MRI. There were significant differences in APT values of the HIE group in bilateral caudate, bilateral thalamus, bilateral centrum semiovale and left globus pallidus/putamen (p < 0.05), and no statistical difference was observed in right globus pallidus/putamen (p = 0.051) and brainstem (p = 0.073) between the two groups. Furthermore, APT values in bilateral caudate, bilateral globus pallidus/putamen, bilateral thalamus, and brainstem regions (p < 0.05) exhibited positive linear correlations with gestational age in the control group, except for bilateral centrum semiovale (right Pearson's r = 0.554, p = 0.062; left Pearson's r = 0.561, p = 0.058). In the mild HIE groups, no significant correlation with gestational age was found in all regions. Conclusions: APT imaging is a feasible and useful technique with diagnostic capability for neonatal HIE.