摘要目的探讨MRI动态增强扫描早期强化比值联合周围血管管径鉴别诊断乳腺良、恶性病变的价值。方法回顾性分析诊断经手术病理证实，且术前2周内行乳腺MRI平扫和MRI动态增强扫描检查的67例患者，恶性病变35例，良性病变32例。绘制病灶区域ROI，生成动态增强时间信号强度曲线，记录病灶早期强化率、达峰时间、早期强化比值，并记录病灶周围3 cm内肿瘤血管数目，测量最粗血管管径。采用Mann?Whitney U秩和检验比较良、恶性病变间DCE?MRI测量值的差异，采用ROC曲线评价病变早期强化率、早期强化比值、血管管径、早期强化比值和血管管径联合鉴别良、恶性病变的效能。结果乳腺恶性病变的达峰时间、早期强化率、早期强化比值、血管数目和管径的中位数分别为2.2 s、176.0%、100.0%、4根、2.96 mm，良性病灶上述参数分别为4.7 s、113.3%、81.9%、0根、0.00 mm，差异均有统计学意义（P均<0.05）。采用早期强化率鉴别诊断乳腺良、恶性病变的ROC下面积为0.702，以120.0%为阈值鉴别诊断的敏感度和特异度分别为82.86%、56.25%；采用早期强化比值鉴别诊断的ROC下面积为0.854，以86.0%为阈值鉴别诊断的敏感度和特异度分别为94.29%、68.75%；采用周围血管管径鉴别诊断的ROC下面积为0.896，以2.78 mm为阈值鉴别诊断的敏感度和特异度分别为74.29%、84.38%；早期强化比值联合周围血管管径鉴别诊断的ROC下面积为0.925，诊断敏感度、特异度分别为97.14%、62.50%。结论 MRI动态增强扫描早期强化比值联合周围血管管径鉴别诊断乳腺良、恶性病变敏感度高。

abstractsObjective To investigate the value of early?phase enhancement ratio combined with peripheral vascular diameter in the differential diagnosis of benign and malignant breast lesions using 3.0 T dynamic contrast?enhanced magnetic resonance imaging (DCE?MRI). Methods Sixty seven cases of patients (35 with malignant lesions and 32 with benign lesions in the breasts) were retrospectively analyzed. Their diagnoses were confirmed by surgery and pathology and all the patients underwent breast MRI plain scan and DCE?MRI in the two weeks before surgery. Lesion ROIs were drawn and time?signal intensity curves in the DCE?MRI were generated. Early?phase enhancement rate, time to peak, early?phase enhancement ratio, numbers of tumor vessel within 3 cm of the lesion and diameter of the largest vessel were recorded. Mann?Whitney U test was used to compare the difference of DCE?MRI between benign and malignant lesions, and the ROC curve was used to evaluate the efficiency of early?phase enhancement rate, early?phase enhancement ratio and vascular diameter in differentiating benign and malignant lesions. Results With breast malignant lesions, the medians of time to peak, early?phase enhancement rate, early?phase enhancement ratio, numbers of tumor vessel and vascular diameter were 2.2 s, 176.0%, 100.0%, 4 and&nbsp;2.96 mm respectively, while with benign lesions of these parameters were 4.7 s, 113.3%, 81.9%, 0 and 0.00 mm respectively, and the differences were statistically significant (all P<0.05).When early?phase enhancement rate was used for differential diagnosis of breast benign and malignant lesions, the area under the ROC curve was 0.702 and the sensitivity and specificity were 82.86%and 56.25%with a threshold of 120.0%. When early?phase enhancement ratio was used, the area under the ROC curve was 0.854 and the sensitivity and specificity were 94.29% and 68.75% with a threshold of 86.0%. When peripheral vascular diameter was used, the area under the ROC curve was 0.896 and the sensitivity and specificity were 74.29%and 84.38% with a threshold of 2.78 mm. When early?phase enhancement ratio was combined with peripheral vascular diameter, the area was 0.925 and the sensitivity and specificity were 97.14% and 62.50%. Conclusion In the differential diagnosis of benign and malignant breast lesions under DCE?MRI, early?phase enhancement ratio combining with peripheral vascular diameter has improved sensitivity.