乳腺MR T1 WI动态增强与T2^＊ WI首过灌注成像相结合对乳腺良恶性病变的鉴别价值

Value of Dynamic Contrast-Enhanced T_1-Weighted MR Imaging Combined With T_2~＊-Weighted First-Pass Perfusion Imaging in Differential Diagnosis of Breast Tumors

目的评价在单次乳腺MRI中,结合T1WI动态增强成像(dynamic contrast-enhanced T1-weighted imaging,DCE-T1WI)与T2*W首过灌注成像(T2*-weighted first-pass perfusion imaging,PWI-T2*WI)对乳腺良、恶性病变鉴别诊断的诊断价值。资料与方法 40例患者在一次乳腺MRI中,先进行DCE-T1WI,随后进行PWI-T2*WI。结果DCE-T1WI如果将流出型时间-信号强度曲线作为诊断病灶恶性的阈值,诊断敏感性为74.2%,特异性为88.9%。良、恶性病灶早期强化率差异有统计学意义(P<0.001)。如果将病灶早期强化率90%作为诊断恶性病灶的阈值,敏感性与特异性分别为83.9%、77.8%;PWI-T2*WI将病灶早期信号丢失率20%作为诊断恶性的阈值,敏感性、特异性分别为90.3%、92.9%。良、恶性病灶在PWI-T2*WI早期信号丢失率的重叠范围小于DCE-T1WI早期强化率的重叠范围。就乳腺良、恶性病灶的鉴别诊断价值而言,PWI-T2*WI中病灶早期信号丢失率高于DCE-T1WI病灶早期强化率(A值分别为0.910 vs 0.791,P=0.000)。结论 PWI-T2*WI在鉴别乳腺病灶的良、恶性方面有很高的特异性,在单次乳腺MRI中联合DCE-T1WI与PWI-T2*WI,能够提高乳腺癌诊断的准确性。

Objective To evaluate the diagnostic value and feasibility of dynamic contrast-enhanced T1-weighted MR imaging（DCE-T1WI）combined with T2＊-weighted first-pass perfusion imaging（PWI-T2＊WI） in differential diagnosis of breast tumors.Materials and Methods Forty patients with breast lesions underwent MR imaging with DCE-T1WI,then followed with PWI-T2＊WI.Results When the washout type time-signal curve was regarded as criteria for breast cancer,the sensitivity and specificity were 74.2% and 88.9%.When a signal intensity decrease of 20% or more in DCE-T1WI was regarded as threshold for malignancy,the sensitivity and specificity were 83.9% and 77.8%.When a of 90% signal intensity increase in PWI-T2＊WI was regarded as threshold for for malignancy,the sensitivity and specificity were 90.3% and 92.9%.The benign and malignant overlap obtained by signal intensity decrease on PWI-T2＊WI was less than that obtained by signal intensity increase on DCE-T1WI.ROC analysis showed that the signal intensity decrease on the PWI-T2＊WI had higher diagnostic value than the signal intensity increase on the DCE-T1WI（A=0.910 vs 0.791,respectively,P=0.000）.Conclusion PWI-T2＊WI can help differential diagnosis benign and malignant breast lesions with high specificity.The combination of DCE-T1WI and PWI-T2＊WI is a feasible one-station breast MR examination and may improve diagnosis accuracy.