磁共振扩散加权成像鉴别诊断鼻腔、鼻窦实性肿块的适宜b值  

Optimal b value on MR diffusion weighted imaging in differential diagnosis of solid sinonasal tumors

作　　者：王永哲[1] 杨本涛[1] 鲜军舫[1] 李静[1] 王新艳[1] 

机构地区：[1]首都医科大学附属北京同仁医院放射科,北京100730

出　　处：《中国医学影像技术》2014年第10期1481-1485,共5页Chinese Journal of Medical Imaging Technology

基　　金：北京卫生高层次人才学科骨干资助(2011-3-048)

摘　　要：目的探讨MR DWI鉴别诊断鼻腔、鼻窦实性肿块的适宜b值。方法对61例鼻腔、鼻窦肿块患者术前行常规MR及DWI扫描,选取b值为500、1000 s/mm^2,测量病变实性部位ROI的ADC值,将结果与组织病理学结果对照。比较良恶性病变ADC值的差异。分别在两种b值下以鼻腔、鼻窦良恶性肿块的ADC值作为临界点绘制ROC曲线,计算曲线下面积(Az),确定诊断阈值,评价诊断效能并进行比较。结果b=500 s/mm^2时,21例恶性肿块和40例良性肿块的平均ADC值为(1.07±0.32)×10^(-3)mm^2/s、(1.90±0.62)×10^(-3)mm^2/s(P<0.001),Az为O.929,以ADC值:1.31×10^(-3)mm^2/s作为预测鼻腔、鼻窦良恶性病变的诊断阈值,其敏感度为85.7%,特异度为95.0%,准确率为91.8%。b=1000 s/mm^2时。21例恶性肿块和40例良性肿块的平均ADC值分别为(0.86±0.25)×10^(-3)mm^2/s、(1.55±0.41)×10^(-3)mm^2/s(P<0.001),Az为0.963.以ADC值=1.10×10^(-3)mm^2/s作为预测鼻腔鼻窦良恶性病变的诊断阈值,其敏感度为85.7%.特异度为97.5%,准确率为93.1%;两组b值的Az间差异无统计学意义(P>0.05)。b=500 s/mm^2时的图像信噪比明显高于b=1000 s/mm^2的信噪比。结论 b=500 s/mm^2时在保证更好图像质量的同时具有较好的诊断效能,更适宜鼻腔、鼻窦肿块的鉴别诊断。Objective To evaluate the optimal b value on MR DWI for differential diagnosis of solid sinonasal tumors. Methods All of 61 patients with sinonasal masses underwent the preoperative routine MR and DWI scan with two b factors of 500 s/mm2and 1000 s/mm2, the ADC values were measured in ROI, which compared with histopathological findings. The statistical analysis were made between benign and malignant masses. The ROCs of two b value were constructed using various cut points of ADC for different b values to confirm the diagnostic threshold value, and the differential diagnostic efficacy were evaluated. Results On b=500 s/mm2 , the mean ADC value in 21 malignant masses and 40 benign masses was （1.07±0.32） ×l0 -3 mm2/s, （1.90±0.62）×10 -3mm2/s （P〈0.001）. The area under the ROC was 0.929. Using an ADC value of 1.31 × 10-3 mm2/s as the threshold value for differentiating malignant lesions, the sensitivity, specificity and accuracy was 85.7%, 95.0%and 91.8%. On b=1000 s/mm2 , the mean ADC value in 21 malignant masses and 40 benign masses was （0.86±0.25）× 10-3mm2/s, （1.55±0.41） × 10-3 mm2/s （P〈0.001）. The area under the ROC was 0. 963. Using an ADC value of 1.10 X 10-3 mm2/s as the threshold value for differentiating malignant lesions, the sensitivity, specificity and accuracy was 85.7%, 97.5% and 93.4%. There was no statistical difference between area under the ROC of two b values （P〉0.05）. SNR of b=500 s/mm2 was significantly higher than that of b= 1000 s/mm2. Conclusion The proper b value in differential diagnosis of sinonasal masses is 500 s/mm2 for the better image quality and the high diagnostic efficacy.

关 键 词：鼻肿瘤 扩散磁共振成像 表观扩散系数 

分 类 号：R765.2[医药卫生—耳鼻咽喉科] R455.2[医药卫生—临床医学]