单指数DWI和IVIM-DWI对前列腺中央腺体疾病的诊断效能

Diagnostic performance of monoexponential DWI and IVIM-DWI for central gland prostate diseases

目的探讨传统单指数DWI和体素内不相干运动DWI(IVIM-DWI)对中央腺体区(CG)前列腺癌(PCa)及良性前列腺增生(BPH)的诊断价值。方法收集经超声引导穿刺病理证实的52例CG区前列腺病变的患者,其中PCa患者18例,共32个病灶(PCa组);BPH患者34例,共67个病灶(BPH组)。对所有患者均行前列腺单指数DWI(b=0、1 000s/mm2)及IVIM-DWI(b=10、20、30、50、80、100、200、400、1 000、1 500s/mm2)扫描,并计算ADC值、纯水分子扩散系数(D值)、灌注相关扩散系数(D*值)、灌注分数(f值)。比较2组间各参数值的差异,并评价各参数值的诊断效能。结果CG区PCa组的ADC值、D值明显低于BPH组,差异均有统计学意义(P均<0.01);2组间D*值及f值差异无统计学意义(P均>0.05)。D值的曲线下面积为0.937(P<0.001),敏感度、特异度分别为89.60%、96.90%;ADC值曲线下面积为0.876(P<0.001),敏感度、特异度为91.00%、71.90%。D值曲线下面积大于ADC值(Z=1.299,P<0.05)。结论单指数DWI和IVIM-DWI可诊断和鉴别诊断CG区PCa和BPH,D值具有较高的诊断效能。

Objective To explore the diagnostic values of traditional monoexponential DWI and intravoxel incoherent motion DWI （IVIM-DWI） in differentiating the central gland （CG） prostate cancer （PCa） from benign hyperplasia （BPH）.Methods Totally 18 PCa patients with 32 focis （PCa group） and 34 BPH patients with 67 nodules （BPH group） in the CG regions were analyzed. All the patients were proved by ultrasound guided pathology. The patients underwent monoexponential DWI （b-value 0, 1 000 s/mm2） and a 10 b-values （10, 20, 30, 50, 80, 100, 200, 400, 1 000, 1 500 s/mm2） IVIM-DWI. Then the ADC value of the monoexponential DWI and the diffusion constant （D）, pseudodiffusion coefficient of perfusion （D＊） and perfusion fraction （f） values of the IVIM-DWI were calculated. The differences of all parameters between two groups were compared. The diagnostic performance of different parameters were evaluated by using ROC curve.Results The values of ADC and D in PCa group were significantly lower than those in BPH group （all P〈0.01）. There were no significant differences between two groups in D＊ and f values （all P〉0.05）. The area under the ROC curve （AUC） of ADC values was 0.876 （P〈0.001）, and corresponding diagnostic sensitivity and specificity were 91.00% and 71.90%. The AUC of D values was 0.937 （P〈0.001）, and corresponding diagnostic sensitivity and specificity were 89.60% and 96.90%. The AUC of D value was higher than that of ADC value （Z=1.299, P〈0.05）.Conclusion The monoexponential DWI and IVIM-DWI can be used to diagnose and differential diagnose of CG PCa and BPH. The D value can obtain better diagnostic performance than the ADC vlaue.