动态增强减影乳腺磁共振成像研究

目的 评估动态增强减影乳腺磁振成像对乳腺疾病MRI诊断的应用价值。材料与方法 40例临床或乳腺X线摄影提示乳腺异常的患者行动态增强乳腺MRI检查。所有病例均经手术病理证实。乳腺MRI检查首先获取脂肪抑制T2WI图像，然后用FLASH 3D序列（平扫1次，注药后5－6次）获得动态增强图像并进行减影。对比剂采用Gd-DTPA(0.1mmol/kg体重）。对部分早期显著强化病灶的减影图像行最大信号强度投影法（MIP）重建。对比分析减影图像及平扫和增强图像对病灶的显示及定性效果。结果 单独应用减影图像可显示87．5％（35／40）的病灶，对恶性病灶的显示为100％（21／21）。减影图像对病灶的范围和形态学特征的显示较平扫及增强图像更清晰、直观。减影配合MIP技术可显示病灶旁的异常血管。结论 数字减影技术是一种简便易行而有效的后处理技术，动态增强减影乳腺MR图像对乳腺疾病的MRI诊断有重要价值。

Contrast enhanced Subtraction Dynamic MR Imaging of the Breast

Objective To evaluate contrast enhanced subtraction dynamic MRI in the diagnosis of breast diseases.Materials and Methods MRI of breast was performed in 40 patients with mammographic or clinically palpable abnormalities before surgery. Fat suppressed T 2WI was followed by FLASH 3D sequences with which dynamic images data were obtained. With a bolus injection of Gd DTPA (0.1mmol/kg), digital subtraction was performed on selected images. MIP was carried out for enhanced lesions. Subtraction images were compared with the relevant conventional images.Results Subtraction images alone could reveal 87.5% (35/40) of total lesions, and 100% of all malignant lesions (21/21), with the extent and features of the lesions being better demonstrated. Abnormal blood vessels were displayed well on MIP images.Conclusion Digital subtraction is an effective and simple postprocessing technique, and dynamic contrast enhanced subtraction studies are very useful in the diagnosis of breast diseases.