弥散加权成像诊断早期前列腺癌的效能及最佳b值

Diagnostic efficiency of diffusion-weighted imaging in early prostate cancer and the optimal b value

目的探寻弥散加权成像(DWI)技术诊断早期前列腺癌的效能和诊断时的最佳b值。方法给予97例疑似早期前列腺癌患者DWI检查、手术或穿刺病理检查。DWI扫描的b值选用800、1000、1200、1500 s/mm^2。对比不同b值下DWI诊断的早期前列腺癌的敏感度和特异度,并分析ADC值与b值的关系。结果 97例患者的病理检查结果显示,确诊早期前列腺癌65例,其中早期外周腺体前列腺癌35例,早期中央移行带前列腺癌30例。DWI在同一b值下,诊断早期外周腺体前列腺癌约登指数均高于诊断早期中央移行带前列腺癌。随着b值的升高,应用DWI诊断早期前列腺癌的约登指数不断升高;随着b值的升高,恶性病变和良性病变部位的ADC值降低。结论 DWI在早期前列腺癌诊断中具有较高的效能。b值为1500 s/mm2时对早期前列腺癌的诊断效能最高。

Objective To explore the value of diffusion-weighted imaging (DWI) in the diagnosis of early prostate cancer and the best b value. Method A total of 97 patients with suspected early prostate cancer were included in the prospective research. All subjects underwent surgical pathology in combination with DWI, with b value of 800 s/mm^2, 1000 s/mm^2, 1200 s/mm^2, and 1500 s/mm^2, respectively. The sensitivity and specificity of DWI in detecting early prostate cancer with varying b values were compared, and the relationship between ADC value and b value was investigated. Result Pathological findings indicated that, among the 97 cases, 65 had confirmed early prostate cancer, including 35 cases of peripheral zone and 30 cases of transition zone. With same b value, higher Youden index was observed for DWI in peripheral zone prostate cancer compared with transition zone prostate cancer. As b value increased, the Youden index of DWI in diagnosis of early prostate cancer was also raised consistently, while the ADC value in malignant and benign lesions decreased significantly. Conclusion DWI is highly valuable in the diagnosis of early prostate cancer. Selecting the b value of 1500 s/mm^2 can greatly improve the detection efficiency of early prostate cancer.