中文摘要：

目的：探讨MRI导向下“第二眼”超声对乳腺癌诊断的临床作用，以及常规超声对乳腺癌漏诊的原因。方法回顾性分析经手术病理证实为乳腺癌，术前行乳腺常规超声检查结果为阴性，且术前同时行乳腺X线摄影、乳腺MRI和MRI导向下“第二眼”超声检查的52例患者，所有患者术前均经MRI导向下“第二眼”超声体表定位。52例乳腺癌患者共80个病灶。依据乳腺MRI及MRI导向下“第二眼”超声的影像表现，对乳腺内病变类型及乳腺超声背景回声进行分类；在乳腺X线摄影图像上测量并计算乳腺体积。结果52例患者的80个恶性病灶经乳腺MRI和经MRI导向下的“第二眼”超声均检出。7例为双乳病变，21例为双灶性乳腺癌。80个病变中，61个（76.2%）病变所在的乳腺体积〉350 cm3，19个（23.8%）病变所在的乳腺体积≤350 cm3；26个（32.5%）病变所在的乳腺背景回声均匀；54个（67.5%）病变所在的乳腺背景回声不均匀。肿块型病变33个（41.2%），病变最大径0.4～2.9 cm，平均（1.6±0.7）cm，其中最大径〉2.0 cm的病变，其相应乳腺体积均〉350 cm3且背景回声不均匀。非肿块型病变47个（58.8%），病变最大径为0.7～10.3 cm，平均（3.0±2.3）cm。结论乳腺体积较大、乳腺背景回声不均匀、非肿块型病变以及病变最大径较小是造成常规超声检查漏诊的主要因素。MRI导向下“第二眼”超声检查有助于发现可疑病灶。

英文摘要：

Objective To evaluate the clinical application value of MRI-guided“second-look”ultrasound and analyze the causes of missed diagnosis performed by ultrasound. Methods A retrospective review was performed on 52 breast cancer patients （80 lesions）, who underwent mamography, MRI and MRI-directed“second-look”ultrasound. All lesions were proven by histopathology. The imaging information were analyzed by using the breast imaging reporting and data system lexicon and the breast volumes was measured on mamography. Results All of the 52 patients were proven to have breast cancer by MRI-guided“second-look”ultrasound. Seven patients had bilateral synchronous breast cancer, 21 patients had multifocal breast cancer and 80 breast cancer lesions were found by MRI-directed ultrasound.Thirty three lesions were mass MRI lesions, the range of the largest diameters was 0.4 to 2.9 cm, average （1.6±0.7） cm. Forty seven lesions were non-mass MRI lesions, the range of the largest diameters was 0.7 to 10.3 cm, average （3.0±2.3） cm. The breast volumes of 19 lesions （23.8%） were≤350 cm3, 61 lesions（76.2%） were〉350 cm3. Twenty six lesions （32.5%） had homogeneous background echotextures, fifty four （67.5%） lesions had heterogeneous background echotextures. Conclusions MRI-guided ultrasound has great value of clinical application in helping analyzing the reason of missed breast cancer on ultrasound.