Firat Ahmet Kemal, Karakaş Hakki Muammer, Firat Yezdan, Yakinci Cengiz
Inonu University Medical Faculty, Turgut Ozal Medical Center, Department of Radiology, Malatya 44280, Turkey.
Eur J Radiol. 2005 Nov;56(2):192-6. doi: 10.1016/j.ejrad.2005.04.009.
To evaluate the value of diffusion weighted imaging (DWI) in diagnosing ataxia telangiectasia (AT) and to investigate the spatial distribution of cerebral microstructural changes caused by the disease.
Six AT patients (9-13 years) and nine healthy control subjects were examined on 1.5 T scanner. In addition to conventional MR images, DWI were performed with a fat suppressed, multishot spin echo EPI sequence using B values of 0, 500 and 1000 s/mm2. Mean ADC values were measured from 16 different supra and infratentorial location. The difference between controls and AT patients regarding ADC values, and the accuracy, sensitivity and specificity of them in discrimination were analyzed with t-tests, logistic regression analysis, ANOVA and ROC curves.
Conventional images of the controls were normal. In AT patients, the only conventional MR abnormality was cerebellar atrophy. The difference between both groups regarding mean ADC values was not significant for any of the cerebral structures. In contrary to cerebrum, cerebellar mean ADC values of patients and controls were statistically different (p < 0.011-0.0001). Patients and controls were classified with 100% accuracy using ADC values of cerebellar white matter and cortex together (p < 0.016). The cut-off ADC value (0.699 mm2/s) for middle cerebellar cortex had produced highest (100%) sensitivity and specificity. There was a difference between superior, middle and inferior cerebellar cortex regarding ADC values (p < 0.026). Superior cerebellar cortex (0.987+/-0.1956 mm2/s) had higher ADC values than the middle and inferior cerebellar cortex.
DWI provides a supplementary and objective imaging finding in AT. This finding is highly accurate in the radiological discrimination of healthy subjects and AT. Our findings also implicate that AT causes a diffuse atrophy and mostly affects superior part of the cortex.
评估扩散加权成像（DWI）在诊断共济失调毛细血管扩张症（AT）中的价值，并研究该疾病引起的脑微结构变化的空间分布。
对6例9 - 13岁的AT患者和9名健康对照者进行1.5T扫描仪检查。除常规MR图像外，使用B值为0、500和1000 s/mm2的脂肪抑制、多激发自旋回波EPI序列进行DWI检查。从幕上和幕下16个不同位置测量平均表观扩散系数（ADC）值。采用t检验、逻辑回归分析、方差分析和ROC曲线分析对照组和AT患者在ADC值方面的差异，以及它们在鉴别诊断中的准确性、敏感性和特异性。
对照组的常规图像正常。在AT患者中，唯一的常规MR异常是小脑萎缩。两组在任何脑结构的平均ADC值差异均无统计学意义。与大脑相反，患者和对照组的小脑平均ADC值有统计学差异（p < 0.011 - 0.0001）。使用小脑白质和皮质的ADC值一起可将患者和对照组100%准确分类（p < 0.016）。小脑中部皮质的截止ADC值（0.699 mm2/s）产生了最高（100%）的敏感性和特异性。小脑上、中、下皮质在ADC值方面存在差异（p < 0.026）。小脑上皮质（0.987±0.1956 mm2/s）的ADC值高于小脑中和下皮质。
DWI为AT提供了一种补充性的客观影像学表现。这一表现对健康受试者和AT的影像学鉴别诊断具有高度准确性。我们的研究结果还表明，AT导致弥漫性萎缩，且主要影响皮质上部。
