MRI诊断扪诊阴性的乳腺占位性疾病

MRI diagnosis of nonpalpable breast lesions

目的：评价ＭＲＩ诊断扪诊阴性的乳腺疾病的敏感性、特异性并探讨其临床意义。材料与方法：应用ＭＲ快速小角度激发三维成像（ＦＬＡＳＨ－３Ｄ）对２６例Ｂ超或Ｘ线检查提示或怀疑有占位，而临床检查未扪及肿块病人的乳腺进行常规及动态检查。结果：发现孤立性病灶２１个，根据病灶形态、边缘、信号均匀度及增强前后信号的动态变化确定典型癌性病变４例，典型良性病变１１例，非典型病变１１例。经病理学对照，本组病例ＭＲＩ的敏感性为１００％，特异性６５％。结论：对于典型良、恶性病变，ＭＲＩ的特异性较高，尽管对非典型良、恶性病变重叠较大，但ＭＲＩ为这类病变提供了细胞学检查和预防性手术的影像学依据。

Purpose: To evaluate the diagnostic efficacy of MRI and its sensitivity and specificity in nonpalpable breast lesions. Materials and methods: Twenty six women, in whom local lesions of breast were suspected by mammography and (or) ultrosound but without clinically palpable mass, underwent routine magnetic resonance imaging (MRI) and dynamic MR study after injection of Gd DTPA using FLASH sequence (TR=12ms, TE=5ms, FA=25°, NEX=1, Matrix=112×256). Results: Twenty one local lesions were discovered. According to the shape, periphery and signal intensity demonstrated in the dynamic study before and after injection of Gd DTPA, the lesions were classified into typical malignant lesion ( n =4), typical benign lesion ( n =11) and atypical lesion ( n =11). Compared with the pathological results, the sensitivity and the specificity of MRI were 100% and 65%. Conclusion: MRI has a significantly high specficity for typical malignant and benign breast lesions. Despite MRI is nonspecific for atypical change, it provides imaging evidence for cytological examination and operation.