摘要
目的比较扩散加权成像（DWI）与动态对比增强MR成像（DCEMRI）对小乳腺癌的检出敏感性，并评价DWI的临床应用价值。方法经病理证实的48例共70个乳腺小病灶（最大径≤2cm）被纳入研究对象，其中恶性病灶45个，良性25个。所有患者均行DWI和DCEMR／，DCEMRI采用快速小角度激发（FLASH）序列，绘制病灶的时间-信号强度曲线（TIC），DWI采用回波平面成像（EPI）序列加用全局自动校准部分并行采集（GRAPPA）技术，取2个扩散敏感因子（b）值（800、1000s／mm^2）行横断面扫描，测量病灶的表观扩散系数（ADC）值。对2种检查方法的诊断结果进行比较。结果DCEMR／正确诊断了40个小乳腺癌及19个良性小病灶，TIC显示小乳腺癌的敏感性及阳性预测值分别为88．9％（40／45）及87．0％（40／46）。DWI中，在2种b值（800、1000s／mm^2）条件下小乳腺癌平均ADC值分别为（1．153±0．192）×10。和（1．079±0．186）×10。mm。／s，而良性小病灶的平均ADC值为（1．473±0．252）×10^-3和（1．419±0．255）×10^-3mm^2／s；同组患者在2种b值条件下的ADC值差异无统计学意义（P〉0．05），而良恶性2组小病灶的ADC值差异有统计学意义（P〈0．01）；b值取1000s／mm^2时，根据DWI信号结合ADC值测量结果可以正确诊断39个小乳腺癌及19个良性小病灶，其对小乳腺癌检出的敏感性及阳性预测值均为86．7％（39／45）。DWI与DCEMRI的诊断结果有很好的一致性，DWI联合DCEMR／可以提高检出的敏感性及阳性预测值，分别达93．3％（42／45）及91．3％（42／46）。结论DWI对小乳腺癌具有较高的检出率，且ADC值的测量可以为良恶性病变的鉴别提供有价值的诊断信息。
Objective To compare the sensitivity of diffusion weighted imaging （DWI） with dynamic contrast enhanced （DCE） MRI for the detection of small breast cancers and to evaluate the clinical value of DWI. Methods Forty-eight patients with benign （ n = 25） and malignant （ n = 45） small breast lesions （ ≤2 cm） proved by pathology underwent DWI and DCE MRI. The DCE MRI was performed using FLASH sequence and the time-signal intensity curve was drawn. The DWI was performed using GRAPPA- EPI sequence with different b values （800, 1000 s/mm^2 ） and the ADC values of lesions were measured. The sensitivity and specificity of DWI for the detection of small breast cancers were compared with DCE MRI. Results Forty of 45 small breast cancers and 19 of 25 small benign breast lesions were correctly diagnosed using DCE MRI. The sensitivity and positive predictive value of TIC were 88. 9% （40/45） and 87.0% （40/46）. With b values of 800 s/mm^2 and 1000 s/mm^2, the average ADC values of small breast cancers were （ 1. 153 ±0. 192） × 10^-3 and（ 1. 079 ±0. 186） × 10-3mm^2/s, while those of benign ones were （ 1. 473 ± 0. 252 ） × 10^-3 and （ 1. 419 ± 0. 255 ） ×10^-3 mm^2/s, respectively. There was no significant difference for the ADC values with different b values in the same group （ P 〉 0. 05）, while there was a significant difference between the malignant and the benign lesions （ P 〈 0.05 ）. Thirty-nine of 45 small breast cancers and 19 of 25 small benign breast lesions were correctly diagnosed using DWI with b value of 1000sec/mm2. Both the sensitivity and positive predictive value of diagnosis were 86. 7% （39/45）. The abilities of DWI and DCE MRI for the diagnosis of small breast cancers were the same. The sensitivity （93. 3% ） and positive predictive value （91.3%） were improved with the combination of DCE MRI and DWI. Condnsion DWI has a high sensitivity for the detection of small breast cancers, the ADC value can provide valuable information in the differ
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2008年第2期152-156,共5页
Chinese Journal of Radiology
关键词
乳腺肿瘤
磁共振成像
弥散
图像增强
Breast neoplasm
Magnetic resonance imaging
Diffusion
Image enhancement
