低场MRI对诊断乳腺肿块的临床应用研究

目的：探讨低场强MRI对诊断乳腺肿块的临床应用价值。方法：对25例共26例临床可扪及的乳腺肿块患者行T1WI和STIR横断面及矢状面扫描，逐个记录肿块的MRI形态和信号特征，依据肿块的形态、边缘、纵横比、内部信号、周围腺体及皮肤改变、腋窝淋巴结肿大等表现对肿块性质进行前瞻性分析判断，和手术及病理结果对照，计算MRI对诊断乳腺肿块的准确性。结果：乳腺囊肿于T1WI信号有特异性，乳腺实性肿块于T1WI信号无特征性，但可以显示肿块形态及与腺体下脂肪垫的关系。STIR可清晰显示乳腺肿块的形态和信号特征，并可同时显示肿块同腺体、皮肤及腋窝淋巴结肿大的关系。良恶性肿块间在形态、边缘、纵横比及内部信号特征方面具有显著性差异。结合STIR所显示的乳腺肿块的形态和信号特点，MRI诊断乳腺肿块的敏感性为93％，准确率为81％。结论：低场强MRI是诊断乳腺肿块的理想手段，尤其在诊断乳腺囊肿、乳腺炎和典型的浸润性导管癌及乳腺纤维腺瘤方面效果明显。

Clinical application of low field MRI in the diagnosis of breast masses

Objective:To evaluate the clinical application of low field MRI in the diagnosis of breast masses.Methods:26 clinically palpable breast masses in 25 women underwent MR imaging with transverse T 1WI,STIR and saggital STIR. Prospectively analyzed were the shape,boundary,depth to width ratio,signal intensity inside the mass,the adjacent skin and glandular tissue changes as well as the axillary lymph node enlargement.The results were correlated to operation and pathological findings.Finally,the diagnostic accuracy of the breast masses was statistically calculated.Results:Cysts of the breast had characteristic signal on T 1WI.Different solid masses had no characteristic signal on T 1WI,however,the shape of the masses and the subglandular fat pad were clearly demonstrated.STIR could reveal clearly the characteristics of both the shape and the texture of the breast masses.And the relationship between the mass and adjacent glandular tissue,skin and axillary lymph node enlargement was also clearly showed in STIR.There was significant difference between infiltrative ductal carcinoma and benign breast masses in their shape,margin,depth to width ratio and texture of internal signal intensity.With STIR sequence,diagnostic sensitivity of MRI was 93%,and accuracy 81%.Conclusion:Low field MRI is a promising method in the diagnosis of palpable breast masses,especially of cyst,inflammation,typical invasive ductal carcinoma and fibroadenoma.