Yu Hon J, Bahri Shadfar, Gardner Vance, Muftuler L Tugan
John Tu and Thomas Yuen Center for Functional Onco-Imaging, University of California, Irvine Hall 164, Irvine, CA, 92697-5020, USA.
Department of Radiological Sciences, University of California, Irvine, CA, 92697-5020, USA.
Eur Spine J. 2015 Nov;24(11):2442-8. doi: 10.1007/s00586-014-3721-0. Epub 2014 Dec 14.
To evaluate the role of apparent diffusion coefficient (ADC) as a quantitative means to assess the degree of intervertebral disc (IVD) degeneration contextually within the framework of a widely used Pfirrmann classification rather than in a direct correlation with Pfirrmann grades.
DWI and T2-weighted (T2w) of lumbar spine were acquired from nine healthy volunteers (age range 27-62 years, mean age 45 years) with a 3T MR scanner. ADC values were obtained from each of the five lumbar discs via a pixel-by-pixel ADC calculation as well as via region of interest-averaged image intensities. Disc degeneration was assessed by a scoring system via sequential application of Pfirrmann scale and use of intensity ratio of IVD/cerebrospinal fluid in T2w for discs in each Pfirrmann grade to be further separated.
A significant correlation was observed between degenerative scores and ADC independent of how ADC was obtained (Spearman's ρ < -0.85, P < 2 × 10(-14)).
This study demonstrates that previously perceived as an overlap in ADC value existing between different degenerative categories based on a visual inspection can be viewed as a quantitative role of ADC in assessment of disc degeneration. This reinforces the Pfirrmann classification system but also proceeds beyond mere qualitatively determining morphologic states.
在广泛使用的Pfirrmann分类框架内，评估表观扩散系数（ADC）作为一种定量手段来评估椎间盘（IVD）退变程度的作用，而非与Pfirrmann分级直接相关。
使用3T磁共振成像扫描仪，对9名健康志愿者（年龄范围27 - 62岁，平均年龄45岁）的腰椎进行扩散加权成像（DWI）和T2加权成像（T2w）。通过逐像素计算ADC值以及通过感兴趣区域平均图像强度，从五个腰椎椎间盘中获取ADC值。通过依次应用Pfirrmann分级系统以及使用T2w图像中IVD与脑脊液的强度比来进一步区分每个Pfirrmann分级的椎间盘退变情况，以此进行评分系统评估。
观察到退变评分与ADC之间存在显著相关性，与获取ADC的方式无关（Spearman's ρ < -0.85，P < 2 × 10(-14)）。
本研究表明，基于视觉检查先前认为不同退变类别之间存在的ADC值重叠，可被视为ADC在评估椎间盘退变中的定量作用。这强化了Pfirrmann分类系统，但也超越了单纯定性确定形态学状态。
