乳腺弥散加权成像在乳腺疾病中的作用

The role of diffusion-weighted imaging for breast MRI

背景与目的:乳腺弥散加权成像(diffusion-weighted imaging,DWI)是一种无创伤性的磁共振检查方法,能否替代乳腺磁共振动态增强扫描(dynamic contrast-enhanced,DCE)做为乳腺癌筛查的方法,本研究就此来探讨乳腺弥散加权成像在乳腺良恶性疾病中的作用。方法:74例患者均进行数字乳腺X线、DCE及DWI检查。49例取b值为0、400、600和800 s/mm2。比较DWI和DCE的检出率、灵敏度和特异度;标准化表观弥散系数(apparent diffusion coefficient,ADC)值和ADC绝对值在乳腺癌检出率中的定量分析比较。结果:经手术证实,64/74例病理结果为阳性(38例为恶性病变,26例为良性病变)。经DWI和DCE检查,恶性病变的检出率为100%。b值分别取400、600和800 s/mm2时,DWI在乳腺良恶性病变鉴别中的诊断灵敏度分别为83.33%、90.00%和93.33%,特异度为85.91%、76.19%和72.72%;DCE的灵敏度和特异度分别为86.61%和90.48%;标准化ADC值和ADC绝对值在乳腺癌的检出率中差异无统计学意义(P>0.05)。结论:DWI在乳腺疾病的鉴别诊断中,具有一定的优越性,是继常规乳腺磁共振增强检查的重要补充方法。

Background and purpose：Diffusion-weighted imaging （DWI） is a non-invasive technique of breast magnetic resonance imaging （MRI）. DWI is an alternative to dynamic contrast-enhanced （DCE） MRI for differentiating malignant from benign lesions in breast screening or not. This study aimed to evaluate the potential role of DWI in differentiating malignant breast lesions from benign lesions.Methods：Seventy-four patients underwent digital mammography, DCE and DWI （49 patients’b-value of 0, 400, 600 and 800 s/mm2）. The detectability, sensitivity and speciifcity of DWI and DCE were compared. Absolute apparent diffusion coefifcient （ADC） was compared with standardized ADC for quantitative analysis.Results：Sixty-four of 74 patients had positive pathologic findings （38 malignant, 26 benign）. All of the malignant lesions were detected on DWI and DCE. The sensitivity of DWI was 83.33%, 90.00% and 93.33%, and the specificity was 85.91%, 76.19% and 72.72%, forb-value of 400, 600 and 800 s/mm2, respectively. The sensitivity and speciifcity of DCE were 86.61% and 90.48%. There was no signiifcant difference between absolute and standardized ADC in detecting breast cancer （P〉0.05）.Conclusion：DWI is an important complemented technique to DCE-MRI for differentiating malignant from benign lesions in breast MRI.