中文摘要：

目的探讨3T MRI扩散张量成像（diffusion tensor imaging,DTI）联合波谱成像（MR spectroscopy,MRS）用于前列腺癌的诊断价值。方法 45例临床高度可疑的前列腺癌患者同时行DTI、MRS检查,与病检结果对照,分析癌区和非癌区的平均表观扩散系数值（apparent diffusion coefficients,ADC）、各向异性分数值（fractional anisotropy,FA）、（胆碱＋肌酐）/枸橼酸盐值（choline＋creatinine/citrate,CC/C）的差异。通过逻辑回归构建诊断模型,对比分析ADC、FA、DTI、MRS、DTI＋MRS诊断前列腺癌的ROC曲线下面积（the area under the ROC curve,AUC）,计算DTI、MRS、＂DTI和MRS＂、＂DTI或MRS＂的敏感度、特异度、阳性预测值、阴性预测值。结果 38例患者顺利通过检查并获得可分析图像。无论外周带或中央区,癌区的ADC值均显著低于非癌区（P〈0.01）,癌区的FA、CC/C值均显著高于非癌区（P〈0.01,P〈0.05）。在外周带,DTI＋MRS的AUC显著高于单独应用DTI、MRS（P〈0.01）;在中央区,DTI＋MRS的AUC显著高于DTI（P〈0.01）,与MRS比较差异无统计学意义（P〉0.05）。＂DTI和MRS＂在外周带及中央区均获得最高特异度,显著高于单独的DTI、MRS（P〈0.05）;＂DTI或MRS＂获得最高敏感度,在外周带显著高于单独的MRS（P〈0.01）,在中央区显著高于单独的DTI（P〈0.01）。结论 DTI联合MRS较单独DTI、MRS更有助于前列腺癌的诊断。

英文摘要：

Objective To evaluate the diagnostic value of diffusion tensor imaging（ DTI） combined with MR spectroscopy（ MRS） for prostate cancer. Methods A total of 45 patients with high suspicion of prostate cancer admitted in our department from May 2012 to June 2013 were enrolled in this study. They all underwent DTI and MRS. MRI data were correlated with their pathological results. The average values of apparent diffusion coefficients（ ADC）,fractional anisotropy（ FA） and choline ＋ creatinine / citrate（ CC / C） in cancerous and noncancerous regions were measured. Logistic regression was used to construct diagnostic models,the areas under the ROC curve（ AUC） were compared between ADC,FA,DTI,MRS,and DTI ＋ MRS. The sensitivity,specificity,positive predictive value and negative predictive value of DTI,MRS,and DTI ＋ MRS,and DTI / MRS were calculated. Results There were 38 patients acquired images that could be analyzed. Whether in peripheral zone（ PZ） or central zone（ CZ）,the ADC value of cancerous regions was significantly lower than that of noncancerous regions（ P〈0. 01）,while the FA and CC / C value were significantly higher than noncancerous regions（ P〈0. 01,P〈0. 05）. In the PZ,the AUC for DTI ＋ MRS was significantly higher than that for either DTI or MRS alone（ P〈0. 01）. In the CZ,the AUC for DTI ＋ MRS was significantly higher than that of DTI alone（ P〈0. 01）,but no difference than MRS（ P〈0. 05）. DTI ＋ MRS had the highest specificity both in PZ and CZ,significantly higher than that for either DTI or MRS（ P〈0. 05）. DTI / MRS had the highest sensitivity,significantly higher than MRS in the PZ（ P〈0. 01） and significantly higher than DTI in the CZ（ P〈0. 01）. Conclusion The combination of DTI and MRS performs better than either technique alone in the diagnosis of prostate cancer.