动态增强磁共振成像在鉴别乳腺良恶性肿瘤中的价值

Differentiation of Benign from Malignant Breast Tumor by Dynamic Enhanced MRI

目的 :评价动态增强磁共振成像鉴别乳腺良恶性肿瘤的价值。材料和方法 :经手术病理证实的乳腺肿块52例 ,其中恶性肿瘤38例 ,良性肿瘤14例。动态增强采用2DFSPGR序列 ,注射造影剂后连续扫描 ,持续至注药后8～10min ,扫描次数约25～30次。以形态学、增强曲线、增强参数多种诊断标准进行诊断价值的评价。结果 :依靠形态学表现鉴别良恶性肿块具有最高的特异性为93 %,依靠增强曲线的形态来鉴别具有最高的敏感性为100 %,同时结合两者来进行鉴别敏感性和特异性都达最高 ,诊断准确率为98 %。运用最大强化斜率、注药后1min的强化率、注药后2min的强化率等定量指标 ,分别以>3 %/s ,>70 %,>90 %为标准可以达到较高的敏感性和特异性 ,分别为89 %,79 %;95 %,64 %;82 %,79 %。结论 :磁共振动态增强对于鉴别乳腺良恶性肿瘤具有较大的价值 ,同时结合肿瘤的形态学表现和增强曲线类型可以提高诊断的准确率。

Purpose:To evaluate the value of dynamic enhanced MRI in distinguishing benign and malignant breast tumors.Materials and Method:2DFSPGR was used to scan 45 patients with histologically proved benign (14) and malignant (38) breast tumors on a GE 1.5T scanner using a breast phase-array coil.The scan was begun right after the Gd-DTPA administration,and was continuously scanning till 8～10min after the injection.The value of dynamic enhanced MRI was evaluated by calculating the sensitivity and specificity,for which the criteria of morphology,enhancement curve type and enhancement parameters were used.Results:By using the criteria of morphology,the specificity was the highest(93%),and by enhancement curve type,the sensitivity was the highest(100%),on combining these two,the sensitivity and specificity all reached the highest,the diagnostic accuracy was 98%.For the quantitative indexes such as the steepest sloop and enhancement ratio(1min,2min),when the criteria of >3%/s,>70%,>90% were used,the sensitivity and specificity all reached maximum,being 89%,79%; 95%,64% and 82%,79% respectively.Conclusion:In differentiating benign from malignant breast tumor by dynamic enhanced MRI,higher diagnostic accuracy will be reached when morphology and enhancement curve type criteria are combined.