Haefeli J, Mabray M C, Whetstone W D, Dhall S S, Pan J Z, Upadhyayula P, Manley G T, Bresnahan J C, Beattie M S, Ferguson A R, Talbott J F
From the Departments of Neurological Surgery (J.H., S.S.D., P.U., G.T.M., J.C.B., M.S.B., A.R.F.).
Weill Institute for Neurosciences, Brain and Spinal Injury Center (J.H., W.D.W., S.S.D., J.Z.P., P.U., G.T.M., J.C.B., M.S.B., A.R.F., J.F.T.).
AJNR Am J Neuroradiol. 2017 Mar;38(3):648-655. doi: 10.3174/ajnr.A5021. Epub 2016 Dec 22.
Acute markers of spinal cord injury are essential for both diagnostic and prognostic purposes. The goal of this study was to assess the relationship between early MR imaging biomarkers after acute cervical spinal cord injury and to evaluate their predictive validity of neurologic impairment.
We performed a retrospective cohort study of 95 patients with acute spinal cord injury and preoperative MR imaging within 24 hours of injury. The American Spinal Injury Association Impairment Scale was used as our primary outcome measure to define neurologic impairment. We assessed several MR imaging features of injury, including axial grade (Brain and Spinal Injury Center score), sagittal grade, length of injury, maximum canal compromise, and maximum spinal cord compression. Data-driven nonlinear principal component analysis was followed by correlation and optimal-scaled multiple variable regression to predict neurologic impairment.
Nonlinear principal component analysis identified 2 clusters of MR imaging variables related to 1) measures of intrinsic cord signal abnormality and 2) measures of extrinsic cord compression. Neurologic impairment was best accounted for by MR imaging measures of intrinsic cord signal abnormality, with axial grade representing the most accurate predictor of short-term impairment, even when correcting for surgical decompression and degree of cord compression.
This study demonstrates the utility of applying nonlinear principal component analysis for defining the relationship between MR imaging biomarkers in a complex clinical syndrome of cervical spinal cord injury. Of the assessed imaging biomarkers, the intrinsic measures of cord signal abnormality were most predictive of neurologic impairment in acute spinal cord injury, highlighting the value of axial T2 MR imaging.
脊髓损伤的急性标志物对于诊断和预后评估均至关重要。本研究的目的是评估急性颈髓损伤后早期磁共振成像生物标志物之间的关系，并评估它们对神经功能障碍的预测效度。
我们对95例急性脊髓损伤患者进行了一项回顾性队列研究，这些患者在受伤后24小时内接受了术前磁共振成像检查。采用美国脊髓损伤协会损伤量表作为我们定义神经功能障碍的主要结局指标。我们评估了损伤的几个磁共振成像特征，包括轴位分级（脑与脊髓损伤中心评分）、矢状位分级、损伤长度、最大椎管狭窄以及最大脊髓压迫。在进行数据驱动的非线性主成分分析后，接着进行相关性分析和最优尺度多变量回归以预测神经功能障碍。
非线性主成分分析确定了2组与1）脊髓内在信号异常测量指标和2）脊髓外在压迫测量指标相关的磁共振成像变量。脊髓内在信号异常的磁共振成像测量指标最能解释神经功能障碍，即使在校正手术减压和脊髓压迫程度后，轴位分级仍是短期神经功能障碍最准确的预测指标。
本研究证明了应用非线性主成分分析来定义颈髓损伤这一复杂临床综合征中磁共振成像生物标志物之间关系的实用性。在所评估的成像生物标志物中，脊髓信号异常的内在测量指标对急性脊髓损伤中的神经功能障碍最具预测性，突出了轴位T2磁共振成像的价值。
