动态增强MRI鉴别乳腺良恶性病变的价值

目的：探讨动态增强MRI对乳腺良恶性病变的鉴别诊断价值。方法：对147例经手术病理证实的乳腺疾病患者行MRI平扫和动态增强检查。分析比较乳腺良恶性病变的MRI征象。包括形态学、内部信号及其动态增强特征等，计算病灶峰值增强率Emax，峰值时间Tmax，最大强化速率Slope max，并根据病变最高强化区ROI测量值，绘制病灶的时间-信号强度曲线。结果：147例患者共计病灶152个。其中恶性87个，良性65个。分析比较病变的形态学及动态增强表现，发现乳腺良性病变多呈类圆形或分叶状．边缘光整，无毛刺、边界多清晰，强化均匀或伴有内部分隔等，动态强化参数Emax多大于90％，Tmax多大于240s。Slopemax。多大于3％／s；恶性病变则多为不规则形。边缘可伴毛刺，与周围结构分界不清，强化不均匀，病灶常呈环形强化，导管样强化，Emax多大于90％，Tmax多大于240s。而Slopemax多大于3％／s。时间-信号曲线类型恶性病变多表现为Ⅱ或Ⅲ型，良性病变则多为Ⅰ或Ⅳ型。结论：乳腺MRI不仅提供了病灶丰富的形态学信息，而且还通过动态增强进一步揭示病变的血流动力学特征，从而有助于对乳腺病变作出准确的定性诊断，更有效地鉴别诊断乳腺良恶性病变。

The Dynamic-Contrast MRI Manifestation of Breast Lesions

Obiective:To investigate the value of contrasted MRI on diagnosis of breast lesions.Methods:147 patients were enrolled in this study who were confirmed as breast lesions verified by surgery and histopathology.All the lesions were evaluated by plain and contrasted MRI.The lesion detectability of T_1WI,T_2WI,and contrasted series,the signal intensity character,enhancement pattern,morphology manifestation of the lesions were observed.Results:147 patients had 87 malignant and 65 benign lesions.There were significant difference between benign and malignant tumors on enhancement homogenity,morphology and margin characteristics (P<0.05).According to the morphology character and enhancement pattern,the rate of sensitivity,specifity and accuracy were 95.5%,83.9%,90.2%.Conclusion:Enhanced MRI is better than plain exam on lesion detection.Benign and malignant breast tumors can be differentiated according to the morphology characteristic and enhancement pattern.