Qi Ying, Liu Peiying, Lin Zixuan, Lu Hanzhang, Wang Xiaoming
Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China.
Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
Front Physiol. 2018 Mar 19;9:233. doi: 10.3389/fphys.2018.00233. eCollection 2018.
The brain's hemodynamic and metabolism of punctate white matter lesions (PWML) is poorly understood due to a scarcity of non-invasive imaging techniques. The aim of this study was to apply new MRI techniques to quantify cerebral metabolic rate of oxygen (CMRO), global cerebral blood flow (CBF), oxygen saturation fractions in venous blood (Yv) and oxygen extraction fraction (OEF) in neonates with PWML, for better understanding of the pathophysiology of PWML. Fifty-one newborns were recruited continuously, including 23 neonatal patients with PWML and 28 normal control neonates. Phase-contrast (PC) MRI and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI were performed for the measurement of CBF and Yv. OEF and CMRO were calculated from the CBF and Yv values. The total maturation score (TMS) was assessed for each neonate on standard T1, 2-weighted images to evaluate cerebral maturation. The CMRO, CBF, Yv, and OEF values were compared between groups, and their associations with age and TMS were evaluated. Significant differences between PWML group and control group were found in CMRO ( = 0.020), CBF ( = 0.027), Yv = 0.012), OEF ( = 0.018). After age/maturation is accounted for, Yv and OEF showed significant dependence on the groups ( < 0.05). Newborns with PWML had lower OEF and higher Yv. CMRO, CBF and brain volume were correlated with age ( < 0.001) and TMS ( < 0.05). It is feasible to use non-invasive MRI methods to measure cerebral oxygen supply and consumption in neonates with PWML. Newborns with PWML have lower oxygen consumption. Yv and OEF may be helpful for the diagnosis of PWML. The positive correlation between CBF and TMS, and between CMRO and TMS suggested that as myelination progresses, the blood supply and oxygen metabolism in the brain increase to meet the escalating energy demand.
由于缺乏非侵入性成像技术，人们对脑点状白质病变（PWML）的血流动力学和代谢了解甚少。本研究的目的是应用新的MRI技术量化PWML新生儿的脑氧代谢率（CMRO）、全脑血流量（CBF）、静脉血氧饱和度分数（Yv）和氧摄取分数（OEF），以更好地理解PWML的病理生理学。连续招募了51名新生儿，包括23名患有PWML的新生儿患者和28名正常对照新生儿。采用相位对比（PC）MRI和自旋标记下的T2弛豫（TRUST）MRI测量CBF和Yv。根据CBF和Yv值计算OEF和CMRO。在标准T1、T2加权图像上评估每个新生儿的总成熟评分（TMS），以评估脑成熟度。比较两组之间的CMRO、CBF、Yv和OEF值，并评估它们与年龄和TMS的相关性。PWML组与对照组在CMRO（P = 0.020）、CBF（P = 0.027）、Yv（P = 0.012）、OEF（P = 0.018）方面存在显著差异。在考虑年龄/成熟度后，Yv和OEF显示出对组的显著依赖性（P < 0.05）。患有PWML的新生儿OEF较低而Yv较高。CMRO、CBF和脑体积与年龄（P < 0.001）和TMS（P < 0.05）相关。使用非侵入性MRI方法测量PWML新生儿的脑氧供应和消耗是可行的。患有PWML的新生儿氧消耗较低。Yv和OEF可能有助于PWML的诊断。CBF与TMS之间以及CMRO与TMS之间的正相关表明，随着髓鞘形成的进展，大脑中的血液供应和氧代谢增加，以满足不断增加的能量需求。
