磁共振扩散加权成像在胆囊病变鉴别诊断中的价值

目的探讨磁共振扩散加权成像在胆囊病变鉴别诊断中的应用价值。方法回顾性分析经临床手术病理证实的46例胆囊病变患者资料,其中胆囊癌21例,胆囊良性病变25例。手术前均行磁共振DWI检查,b值为0、800s/mm~2。测量病变的ADC值,采用独立样本t检验分析比较胆囊良恶性病变ADC值之间的差异,并运用ROC曲线评价ADC值的诊断效能。结果胆囊癌的ADC值为(1.23±0.19)×10~(-3) mm~2/s,胆囊良性病变的ADC值为(1.93±0.33)×10~(-3)mm~2/s,胆囊癌的ADC值明显低于良性病变(t=-8.57,P0.05)。ADC值诊断胆囊良恶性病变的ROC曲线下面积为0.95,ADC值≤1.42×10~(-3)mm~2/s为阈值时,诊断胆囊癌的敏感度为90.5%,特异度为92.0%,准确度为91.3%。与病理结果行一致性检验,Kappa值为0.825。结论 DWI在胆囊良恶性病变鉴别诊断中具有较好的应用价值。

The Value of MR Diffusion-weighted Imaging in the Differential Diagnosis of Gallbladder Lesions

Objective To retrospectively evaluate the value of MR diffusion-weighted imaging (DWI) in differentiating between benign and malignant gallbladder lesions. Methods Forty-six patients (21 malignancy and 25 benignancy) were reviewed. ADC was calculated using two DW images with different motion-probing gradient strengths (b=0, 800s/mm2). The ADC values of the lesions were measured from ADC maps. Statistical analysis was performed using independent-sample t test. Diagnostic accuracy was evaluated using the receiver operator characteristic method.Results The mean ADC value of cancer was (1.23±0.19)×10-3mm2/s, which was significantly lower than of the benign lesions (1.93±0.33)×10-3mm2/s (t=-8.57, P<0.05). In receiver operating characteristic curve analysis, the areas under the curves for ADC were 0.95. The optimal cutoff values of ADC for differentiating benign and malignant lesions of the gallbladder was 1.42×10-3 mm2/s with sensitivity of 90.5%, specificity of 92.0% and accuracy of 91.3%. And ADC had a high consistency compared with pathological results (Kappa values were 0.825). Conclusion DWI can improve diagnostic accuracy for differentiating malignant from benign gallbladder lesions.