Department of Radiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
J Neuroimaging. 2022 Nov;32(6):1098-1108. doi: 10.1111/jon.13038. Epub 2022 Aug 29.
Pediatric-onset multiple sclerosis (POMS) shows earlier axonal involvement and greater axonal loss than in adults. We aim to characterize the white matter (WM) microstructural changes in POMS using a diffusion compartment imaging (DCI) model and compare it to standard diffusion tensor imaging (DTI).
Eleven patients (2 males, mean age 18.8 ± 3.9 years) with a diagnosis of relapsing and remitting POMS (mean age at disease onset 13.8 ± 2.9 years, mean duration 5.1 ± 1.9 years) and healthy controls (8 males, mean age 26.4 ± 6.5 years) were recruited and imaged at 3 T. A 90-gradient set Cube and Sphere acquisition and a novel DCI model known as DIstribution of Anisotropic MicrOstructural eNvironments with Diffusion-weighted imaging (DIAMOND) were used to calculate a single anisotropic compartment, an isotropic compartment, and a free diffusion compartment. Lesions and contralateral normal-appearing white matter (NAWM) in patients and whole brain WM for controls were labeled.
Eleven patients and 11 controls were recruited. When comparing lesions and contralateral NAWM in patients using DCI, compartmental axial diffusivity, radial diffusivity (cRD), and mean diffusivity (cMD) were higher in lesions. Conversely, compartmental fractional anisotropy (cFA) and heterogeneity index were lower in lesions. An analysis of DTI equivalents showed the same trends. In whole-brain NAWM of patients compared to controls, cRD and cMD were higher and cFA was lower in patients.
Lesions in POMS can be accurately characterized by a DCI model. Incipient changes in NAWM seen in DCI may not be readily observable by DTI.
儿科发病型多发性硬化症（POMS）的轴突受累比成人更早，轴突丢失更多。我们旨在使用扩散隔室成像（DCI）模型来描述 POMS 的白质（WM）微观结构变化，并将其与标准扩散张量成像（DTI）进行比较。
招募了 11 名（2 名男性，平均年龄 18.8±3.9 岁）诊断为复发缓解型 POMS 的患者（平均发病年龄 13.8±2.9 岁，平均病程 5.1±1.9 年）和 11 名健康对照者（8 名男性，平均年龄 26.4±6.5 岁），并在 3T 进行了成像。使用 90 梯度集 Cube 和 Sphere 采集和一种新的 DCI 模型（称为 DIstribution of Anisotropic MicrOstructural eNvironments with Diffusion-weighted imaging，DIAMOND）来计算单个各向异性隔室、各向同性隔室和自由扩散隔室。对患者的病变和对侧正常表现的白质（NAWM）以及对照组的整个脑 WM 进行了标记。
共招募了 11 名患者和 11 名对照者。使用 DCI 比较患者的病变和对侧 NAWM 时，病变中的隔室轴向弥散度、径向弥散度（cRD）和平均弥散度（cMD）更高。相反，病变中的隔室各向异性分数（cFA）和异质性指数更低。DTI 等效物的分析显示出相同的趋势。与对照组相比，患者的全脑 NAWM 中的 cRD 和 cMD 更高，而 cFA 更低。
DCI 模型可以准确地对 POMS 的病变进行特征描述。DCI 中观察到的 NAWM 的早期变化可能不易通过 DTI 观察到。
