Breast cancer has become a “red-faced killer” that threatens the health and lives of women. As many as 1.2 million women worldwide suffer from breast cancer every year, and the incidence rate is increasing at a rate of 0.2% to 8% every year. The number of women suffering from breast cancer in China is increasing, and more than 10,000 patients die from breast cancer every year, especially in some economically developed regions and big cities, breast cancer ranks first among female malignant tumors. Breast disease has become the number one hidden danger to women’s health. In order to improve breast examination, early diagnosis and provide reliable information for timely and correct clinical surgical treatment, our hospital has purchased magnetic resonance breast coil, which is expected to be widely used by clinicians and patients suffering from breast disorders. The sensitivity of MRI is higher than that of mammography, and it can observe the lesion in three dimensions, which can not only provide the morphological characteristics of the lesion, but also provide the hemodynamic situation of the lesion by using dynamic enhancement, which has reached a new level for the diagnosis and detection of breast diseases. It has been widely used for early diagnosis of breast cancer in foreign countries and some major cities in China. Breast MRI has many advantages and it can significantly improve the detection rate of breast diseases, especially early stage breast cancer and occult breast cancer. Breast MRI is needed in the following cases: 1) lesions that cannot be diagnosed by X-ray or B-ultrasound. When the results of mammogram or B-ultrasound are ambiguous, MRI can provide more information and powerful evidence for differential diagnosis. 2.Discovery of occult breast cancer. Some breast cancers only appear as enlarged axillary lymph nodes, which cannot be detected by clinical examination or X-ray photography, but a smaller primary focus can be detected by MRI. 3.Women who have undergone breast enlargement plastic surgery. Breast augmentation surgery into the prosthesis has the possibility of leakage rupture, according to statistics the length of time varies, the average foreign 12 years, the average domestic prosthesis 8 years. About half of the patients have no obvious clinical symptoms, so for those who have had breast implants for a long time, it is recommended that they undergo MRI examination, which can often detect the rupture of the implants at an early stage and enable timely treatment. For the breast after breast augmentation, X-ray examination requires compression of the breast, which may cause secondary rupture of the implant and the risk of hydrogel spread. In contrast, MRI does not have these problems, and it can effectively show the lesion and make a diagnosis. Therefore, if a suspicious lump is found on palpation after breast augmentation surgery, magnetic resonance examination should be performed. 4.Patients who intend to have breast preservation surgery. The significance of breast preservation treatment is to preserve the satisfactory breast shape while completely removing the tumor lesion. Several international studies in the past 30 years have shown that for strictly selected cases, the long-term survival effect of breast-conserving treatment is equivalent to that of total mastectomy. However, conventional mammography and ultrasound tend to underestimate the extent of the tumor and may not show multiple centers and lesions, and additional lesions may be found in other parts of the breast after MRI. For such patients, total mastectomy should be performed instead of breast-conserving surgery. Studies in the United States have shown that approximately 40% of patients who have breast-conserving surgery underestimate the extent of the surgery, resulting in local recurrence. Therefore, for patients suspected of having breast cancer by mammography or confirmed by puncture biopsy, it is recommended to do breast MRI before surgery if you want to preserve your breast. 5. Screening for high-risk group. Screening for high-risk group using MRI is easier to detect suspicious lesions than other imaging examinations, which can achieve early diagnosis and early treatment. The definition of high-risk group for breast cancer is: previous history of breast cancer; relatives with history of breast cancer; those with BRCA gene mutation; those who have had breast biopsy and pathologically confirmed atypical hyperplasia; lobular carcinoma in situ; radiation scar; patients who have had cape field radiotherapy for lymphoma. 6. Evaluation of response to neoadjuvant chemotherapy for breast cancer. Traditional post-surgical adjuvant chemotherapy has considerable blindness and cannot achieve the therapeutic purpose because of the inability to predict the efficacy. Neoadjuvant chemotherapy is administered before surgical treatment, and the effectiveness of the treatment plan can be judged by observing the response of the lesion to the treatment. Chemotherapy can lead to breast fibrosis, which reduces the sensitivity of clinical palpation and mammography. Magnetic resonance examination can determine chemotherapy response based on the reduction in contrast enhancement of the lesion, and this method has a high sensitivity for examining the response after chemotherapy.