DWI及DCE-MRI在良恶性骨病鉴别诊断中的应用

Application of MR diffusion-weighted imaging and dynamic contrast-enhanced MRI in differentiating benign skeletal lesions from malignant ones

目的探讨磁共振扩散加权成像(DWI)及MR动态增强成像(DCE-MRI)在良恶性骨病鉴别诊断中的应用价值。方法47例骨病患者(良性18例,恶性29例)行DWI检查,其中36例(良性14例,恶性22例)再行DCE-MRI检查。分别于DWI和动态增强图像上测量ADC值、信号增强幅度(SEE)、早期动态增强斜率值(Slope值),判断TIC曲线类型,采用受试者操作特征(ROC)曲线选择良恶性病变鉴别诊断的阈值,计算各参数对病变潜在恶性估计的敏感度、特异度和准确度。结果①47例病例中,良恶性两组病变的ADC值分别为(171.15±46.96)×10-5mm2/s、(100.14±26.47)×10-5mm2/s(P<0.05);以113.3×10-5mm2/s为阈值,ADC值对病变潜在恶性评估的准确性为86.4%;②36例病例中,TIC曲线呈Ⅲ型者24例,恶性22例(91.67%),良性2例(8.33%);呈Ⅱ型者5例,Ⅰ型者7例,均为良性病变。若以Ⅲ型为恶性病变,Ⅰ、Ⅱ型均视为良性病变为诊断标准,则TIC类型对病变潜在恶性评估的准确性为94.3%;③良恶性两组间SEE、Slope值分别为227.96±172.08、325.6±125.86(P>0.05);(0.97±0.67)%/s、(2.53±0.91)%/s(P<0.05)。Slope值对病变潜在恶性估计的准确性为91.4%。结论①DCE-MRI比DWI更有助于鉴别骨骼系统病变良恶性,以TIC类型准确性最高,最有价值;②良恶性病变间ADC值有一定交叉,DCE-MRI存在重叠,联合应用DCE-MRI与DWI,会提高诊断的准确性和特异性。

Objective To assess the diagnostic potential of DWI and DCE-MRI in differentiating benign from malignant skeletal lesions.Methods DWI was performed on 47 patients and DCE-MRI on 36 patients using the Siemens Sonata 1.5T MR scanner.The ADC value was measured on DWI and SEE,and slope value and TIC type were gained on DCE-MRI.Subjective overall performance of the two techniques was evaluated with ROC analysis.Results ① The ADC value of benign and malignant groups was（171.15±46.96）×10^-5mm^2/s,（100.14±26.47）×10^-5mm^2/s（P〈0.05）.The diagnostic accuracy was 86.4%;② In 36 patients,the Ⅲ curve was found in 24（malignant for 22 and benign for 2）,theⅡcurve in 5 andⅠcurve in 7（all were benign）.As the Ⅲ curve was considered malignant and Ⅰ,Ⅱ curve were regarded as benign,the diagnostic accuracy of TIC type was 94.3%;③ SEE was 227.96±172.08and 325.6± 125.86 in benign and malignant groups respectively（P〉0.05）,and slope value was（0.97±0.67）%/s and（2.53±0.91）%/s（P〈0.05）.The diagnostic accuracy of slope value was 91.4%.Conclusion ① DCE-MRI was more valuable than DWI in differentiating benign from malignant skeletal masses.The diagnostic accuracy of the TIC type was highest;② The D combined use of CE-MRI and DWI can promote the accuracy in diagnosing suspicious skeletal masses.