Neuroradiology Unit, Istituto Giannina Gaslini, Genoa, Italy.
Department of Neuroradiology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany.
J Magn Reson Imaging. 2018 Nov;48(5):1199-1207. doi: 10.1002/jmri.26163. Epub 2018 May 10.
Germinal matrix-intraventricular hemorrhage (GMH-IVH) is a common form of intracranial hemorrhage occurring in preterm neonates that may affect normal brain development. Although the primary lesion is easily identified on MRI by the presence of blood products, its exact extent may not be recognizable with conventional sequences. Quantitative susceptibility mapping (QSM) quantify the spatial distribution of magnetic susceptibility within biological tissues, including blood degradation products.
PURPOSE/HYPOTHESIS: To evaluate magnetic susceptibility of normal-appearing white (WM) and gray matter regions in preterm neonates with and without GMH-IVH.
Retrospective case-control.
A total of 127 preterm neonates studied at term equivalent age: 20 had mild GMH-IVH (average gestational age 28.7 ± 2.1 weeks), 15 had severe GMH-IVH (average gestational age 29.3 ± 1.8 weeks), and 92 had normal brain MRI (average gestational age 29.8 ± 1.8 weeks).
FIELD STRENGTH/SEQUENCE: QSM at 1.5 Tesla.
QSM analysis was performed for each brain hemisphere with a region of interest-based approach including five WM regions (centrum semiovale, frontal, parietal, temporal, and cerebellum), and a subcortical gray matter region (basal ganglia/thalami).
Changes in magnetic susceptibility were explored using a one-way analysis of covariance, according to GMH-IVH severity (P < 0.05).
In preterm neonates with normal brain MRI, all white and subcortical gray matter regions had negative magnetic susceptibility values (diamagnetic). Neonates with severe GMH-IVH showed higher positive magnetic susceptibility values (i.e. paramagnetic) in the centrum semiovale (0.0019 versus -0.0014 ppm; P < 0.001), temporal WM (0.0011 versus -0.0012 ppm; P = 0.037), and parietal WM (0.0005 versus -0.0001 ppm; P = 0.002) compared with controls. No differences in magnetic susceptibility were observed between neonates with mild GMH-IVH and controls (P = 0.236).
Paramagnetic susceptibility changes occur in several normal-appearing WM regions of neonates with severe GMH-IVH, likely related to the accumulation of hemosiderin/ferritin iron secondary to diffusion of extracellular hemoglobin from the ventricle into the periventricular WM.
4 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1199-1207.
脑室内出血（GMH-IVH）是早产儿常见的颅内出血形式，可能影响正常脑发育。尽管 MRI 上可以通过血液产物的存在轻松识别原发性病变，但常规序列可能无法识别其确切范围。定量磁化率映射（QSM）可量化生物组织（包括血液降解产物）内的磁化率空间分布。
目的/假设：评估伴有和不伴有 GMH-IVH 的早产儿正常表现的白质（WM）和灰质区域的磁化率。
回顾性病例对照研究。
在胎龄相等时研究了总共 127 名早产儿：20 名患有轻度 GMH-IVH（平均胎龄 28.7±2.1 周），15 名患有严重 GMH-IVH（平均胎龄 29.3±1.8 周），92 名患有正常脑 MRI（平均胎龄 29.8±1.8 周）。
磁场强度/序列：1.5 Tesla 下的 QSM。
采用基于感兴趣区域的方法对每个大脑半球进行 QSM 分析，包括五个 WM 区域（大脑半卵圆中心、额、顶、颞和小脑）和一个皮质下灰质区域（基底节/丘脑）。
根据 GMH-IVH 严重程度，采用单因素协方差分析探索磁化率的变化（P<0.05）。
在正常脑 MRI 的早产儿中，所有白质和皮质下灰质区域均具有负磁化率值（抗磁性）。严重 GMH-IVH 的新生儿大脑半卵圆中心（0.0019 对 -0.0014 ppm；P<0.001）、颞 WM（0.0011 对 -0.0012 ppm；P=0.037）和顶 WM（0.0005 对 -0.0001 ppm；P=0.002）的磁化率值明显更高（顺磁性），与对照组相比。轻度 GMH-IVH 患儿与对照组之间的磁化率无差异（P=0.236）。
严重 GMH-IVH 新生儿的几个正常表现的 WM 区域出现顺磁性磁化率变化，可能与从脑室扩散到脑室周围 WM 的细胞外血红蛋白引起的含铁血黄素/铁蛋白铁的积累有关。
4 级。技术功效：第 3 阶段。磁共振成像杂志 2018；47：1199-1207。
