1.5T磁共振多高b值弥散加权成像信号强度在前列腺癌中的诊断价值

The diagnostic value of 1.5T magnetic resonance multi b DWI signal intensity for prostate cancer

目的探讨1.5T磁共振多高b值弥散加权成像(DWI)的"前列腺癌灶-前列腺非癌灶信号强度比"对前列腺癌的诊断及鉴别诊断价值,确定最佳b值。方法回顾性分析1.5T磁共振多高b值DWI序列扫描并经病理证实的前列腺癌143例,非前列腺癌27例。测量并分析前列腺癌灶原始DWI信号强度与非前列腺癌的相对信号强度随b值变化的诊断效能。结果在高b值区间(600 s/mm^2,800 s/mm^2,1 000 s/mm^2,1 500 s/mm^2,2 000 s/mm^2,2 500 s/mm^2,3 000 s/mm^2)内,前列腺癌的DWI信号强度明显高于非前列腺癌的信号强度,前列腺癌灶的DWI信号强度是非癌灶的1.4~2.3倍;b值越高,癌灶的DWI信号强度衰减越不明显,而相对非癌灶DWI信号强度衰减越明显。在高b值区间(600 s/mm^2,800 s/mm^2,1 000 s/mm^2,1 500 s/mm^2,2 000 s/mm^2,2 500 s/mm^2,3 000 s/mm^2)内,以b=2 500 s/mm^2时的敏感性(93.0%)、特异性(76.9%)及与病理结果对比的准确性(89.6%)对前列腺癌诊断及鉴别诊断的效能最高。结论多高b值DWI信号强度值对前列腺癌的诊断具有较高的诊断价值;以b=2500 s/mm^2为最佳的b值。

Objective To investigate the diagnostic value of 1.5T magnetic resonance imaging with high b value of DWI in the diagnosis of prostate cancer, and to determine the optimal b value. Methods Retrospectively analyze the image data scanned by 1.5T magnetic resonance b high value DWI sequence of 143 cases with prostate cancer pathologically confirmed, and 27 cases with non prostate cancer. Measure and analyze the diagnostic efficacy of relative signal intensity of prostate cancer foci of original DWI signal intensity and non prostate cancer with the change of b value. Results For the high b value interval （600 s/mm^2, 800 s/mm^2,1000 s/mm^2,1500 s/mm^2,2000 s/ mmE,2500s/mm^2,3000s/mm^2）, the signal intensity of DWI signal intensity of prostate cancer was significantly higher than that of non prostate cancer, prostate cancer DWI signal intensity was 1.4-2.3 times of non cancer. The higher the b value was, the less obvious the DWI signal intensity of tumor attenuation was, while relatively the DWI signal intensity attenuation of non cancer was more obvious. Of the high b range （600 s/mm^2, 800 s/mm^2, 1000 s/mm^2, 1500 s/ mm^2, 2000 s/mm^2, 2500 s/mm^2, 3000 s/mm^2）, b=2500 s/mm^2 had the highest efficiency for the diagnosis and differential diagnosis of prostate cancer with the sensitivity of 93.0%, specificity of 76.9% and the accuracy of 89.6% when compared with the pathology results. Conclusion DWI signal intensity of multi high b value has high diagnostic value for the diagnosis of prostate cancer, and b=2500 s/mm^2 is the best b value.