Department of Neurology, Partners Multiple Sclerosis Center, Brigham and Women's Hospital, Harvard Medical School, Massachusetts, USA.
J Neuroimaging. 2012 Jul;22(3):e12-9. doi: 10.1111/j.1552-6569.2011.00629.x. Epub 2011 Aug 19.
To determine the proper method for the normalization of spinal cord volume.
A group of 34 multiple sclerosis (MS) patients (28 relapsing and 6 progressive) and 15 healthy controls had whole spinal cord 3-mm thick T2-weighted axial fast spin-echo magnetic resonance imaging (MRI) images obtained at 3T. For each participant, four volumes were measured (C2-3 volume, cervical cord volume, thoracic cord volume, and whole cord volume). The volumes were normalized by the number of slices and three potential measures of body size (intracranial volume [ICV], body mass index, and body surface area) using the proportional method.
All raw volumes and volumes normalized by number of slices or ICV were significantly lower in progressive MS patients compared to relapsing MS patients/healthy controls (P < .05). In addition, C2-3 volume and cervical cord volume were significantly correlated with Expanded Disability Status Scale score (P < .05). All regional volumes showed high intercorrelation, and normalization by the number of slices significantly increased some correlations. Regarding reliability, whole cord volume regardless of normalization technique had lower coefficient of variation than C2-3 volume.
Since normalization factor had limited impact on reliability and the ability to detect differences, normalization by the number of slices is recommended.
确定脊髓体积标准化的适当方法。
一组 34 名多发性硬化症（MS）患者（28 名复发型和 6 名进展型）和 15 名健康对照者在 3T 上进行了全脊髓 3 毫米厚 T2 加权轴向快速自旋回波磁共振成像（MRI）扫描。对于每个参与者，测量了四个体积（C2-3 体积、颈髓体积、胸髓体积和全脊髓体积）。使用比例法，通过切片数量和三种潜在的身体大小测量指标（颅内体积[ICV]、体重指数和体表面积）对体积进行标准化。
与复发型 MS 患者/健康对照者相比，进展型 MS 患者的所有原始体积和通过切片数量或 ICV 标准化的体积均显著降低（P<.05）。此外，C2-3 体积和颈髓体积与扩展残疾状况量表评分显著相关（P<.05）。所有区域体积之间高度相关，通过切片数量进行标准化显著增加了一些相关性。关于可靠性，无论使用何种标准化技术，全脊髓体积的变异系数均低于 C2-3 体积。
由于标准化因子对可靠性和检测差异的能力影响有限，因此建议通过切片数量进行标准化。
