Inserm UMR 1253, iBrain, Université de Tours, Tours, France.
Pediatric Radiology Department, Clocheville Hospital, CHRU de Tours, 49 Boulevard Beranger, 37000, Tours, France.
Eur Radiol. 2021 Mar;31(3):1505-1516. doi: 10.1007/s00330-020-07194-w. Epub 2020 Sep 3.
This study introduced a tailored MP2RAGE-based brain acquisition for a comprehensive assessment of the normal maturing brain.
Seventy normal patients (35 girls and 35 boys) from 1 to 16 years of age were recruited within a prospective monocentric study conducted from a single University Hospital. Brain MRI examinations were performed at 1.5 T using a 20-channel head coil and an optimized 3D MP2RAGE sequence with a total acquisition time of 6:36 min. Automated 38 region segmentation was performed using the MorphoBox (template registration, bias field correction, brain extraction, and tissue classification) which underwent a major adaptation of three age-group T1-weighted templates. Volumetry and T1 relaxometry reference ranges were established using a logarithmic model and a modified Gompertz growth respectively.
Detailed automated brain segmentation and T1 mapping were successful in all patients. Using these data, an age-dependent model of normal brain maturation with respect to changes in volume and T1 relaxometry was established. After an initial rapid increase until 24 months of life, the total intracranial volume was found to converge towards 1400 mL during adolescence. The expected volumes of white matter (WM) and cortical gray matter (GM) showed a similar trend with age. After an initial major decrease, T1 relaxation times were observed to decrease progressively in all brain structures. The T1 drop in the first year of life was more pronounced in WM (from 1000-1100 to 650-700 ms) than in GM structures.
The 3D MP2RAGE sequence allowed to establish brain volume and T1 relaxation time normative ranges in pediatrics.
• The 3D MP2RAGE sequence provided a reliable quantitative assessment of brain volumes and T1 relaxation times during childhood. • An age-dependent model of normal brain maturation was established. • The normative ranges enable an objective comparison to a normal cohort, which can be useful to further understand, describe, and identify neurodevelopmental disorders in children.
本研究引入了一种定制的基于 MP2RAGE 的脑采集方法，用于全面评估正常发育中的大脑。
本前瞻性单中心研究共纳入了 70 名 1 至 16 岁的正常患者（男 35 例，女 35 例）。使用 20 通道头部线圈和优化的 3D MP2RAGE 序列在 1.5T 磁共振扫描仪上进行脑 MRI 检查，总采集时间为 6:36 分钟。使用 MorphoBox（模板注册、偏置场校正、脑提取和组织分类）进行自动 38 个区域分割，该软件对三个年龄组的 T1 加权模板进行了重大调整。体积和 T1 弛豫时间参考范围分别使用对数模型和改进的戈珀兹生长模型建立。
所有患者均成功进行了详细的自动脑分割和 T1 映射。使用这些数据，建立了一种与体积和 T1 弛豫时间变化相关的正常脑成熟的年龄依赖性模型。在生命的头 24 个月中，总颅内体积快速增加，之后在青春期趋于收敛至 1400mL。白质（WM）和皮质灰质（GM）的预期体积也呈现出相似的年龄趋势。在最初的快速下降之后，所有脑结构中的 T1 弛豫时间被观察到逐渐下降。在生命的第一年，WM（从 1000-1100 降至 650-700ms）中的 T1 下降比 GM 结构更为明显。
3D MP2RAGE 序列可用于建立儿科脑容量和 T1 弛豫时间的正常范围。
• 3D MP2RAGE 序列可对儿童期脑容量和 T1 弛豫时间进行可靠的定量评估。• 建立了一种正常脑成熟的年龄依赖性模型。• 正常范围可以与正常队列进行客观比较，有助于进一步理解、描述和识别儿童神经发育障碍。
