Rozenfeld Michael N, Nemeth Alexander J, Walker Matthew T, Mohan Prasoon, Wang Xue, Parrish Todd B, Opal Puneet
Department of Radiology, University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.
Department of Radiology, Northwestern University, Chicago, IL, USA; Ken and Ruth Davee Department of Neurology, Northwestern University, Chicago, IL, USA.
J Clin Neurosci. 2015 Jan;22(1):166-72. doi: 10.1016/j.jocn.2014.08.006. Epub 2014 Nov 26.
Multisystem system atrophy and spinocerebellar ataxia are rare neurodegenerative ataxias that can be difficult to diagnose, with important prognostic and treatment implications. The purpose of this study is to evaluate various methods of diffusion imaging and tractography in their effectiveness at differentiating these diseases from control subjects. Our secondary aim is determining whether diffusion abnormalities correspond with clinical disease severity. Diffusion imaging and tractography were performed on five patients and seven age-matched controls. Fractional anisotropy, generalized fractional anisotropy, and apparent diffusion coefficient values and corticospinal tract volumes were measured within various diffusion and probabilistic tractography models, including standard diffusion tensor and Q-ball tractography. Standard diffusion based fractional anisotropy and apparent diffusion coefficient values were significantly altered in patients versus controls in the middle cerebellar peduncles and central pons. Tractography based fractional anisotropy and generalized fractional anisotropy values were significantly lower in patients versus controls when corticospinal tracts were drawn in a craniocaudal direction (bilaterally using Q-ball imaging, only on the right using diffusion tensor imaging). The right corticospinal tract volume was significantly smaller in patients versus controls when created using Q-ball imaging in a caudocranial direction. There was no correlation between diffusion alteration and clinical symptomatology. In conclusion, various diffusion-based techniques can be effective in differentiating ataxic patients from control subjects, although the selection of diffusion algorithm and tract growth technique and direction is non-trivial.
多系统萎缩和脊髓小脑共济失调是罕见的神经退行性共济失调，诊断可能存在困难，且具有重要的预后和治疗意义。本研究的目的是评估各种扩散成像和纤维束成像方法在区分这些疾病与对照受试者方面的有效性。我们的次要目的是确定扩散异常是否与临床疾病严重程度相关。对5例患者和7名年龄匹配的对照者进行了扩散成像和纤维束成像。在各种扩散和概率纤维束成像模型中测量了分数各向异性、广义分数各向异性、表观扩散系数值和皮质脊髓束体积，包括标准扩散张量和Q球纤维束成像。在小脑中脚和脑桥中部，基于标准扩散的分数各向异性和表观扩散系数值在患者与对照者之间有显著改变。当沿头尾方向绘制皮质脊髓束时（双侧使用Q球成像，仅右侧使用扩散张量成像），患者与对照者相比，基于纤维束成像的分数各向异性和广义分数各向异性值显著降低。当使用Q球成像沿尾颅方向创建时，患者与对照者相比，右侧皮质脊髓束体积显著减小。扩散改变与临床症状之间无相关性。总之，各种基于扩散的技术在区分共济失调患者与对照受试者方面可能有效，尽管扩散算法、纤维束生长技术和方向的选择并非易事。
