Now a days ,the use of Magnetic Resonance Imaging (or MRI) is not common with initial breast cancer screening but A carefully performed mammogram is much more convenient and economical, and is usually adequate to inform initial decisions as to whether a biopsy is warranted.But by a new study MRI is too preferred against mammography beacuse fear of unnecessary radiation and clear cut diagnosis in suspected patient/

                         Mammograms often reveal the pretense of potentially pre-cancerous microcalcifications, but even with magnetic resonance imaging it is unlikely that a radiologist will be able to distinguish malignant from benign microcalcifications. (The presence of microcalcifications alone might be a benign finding or might indicate a high-risk or early DCIS scenario).However, if a mass or suspicious lesion of a significant size is evident, then breast MRI becomes a very sensitive and effective diagnostic tool.

        MRI is not used for asymptomatic patients with average risk. It is also not indicted for examination of microcalcifications, for inflammatory changes, or for ‘dense tissue‘ found at mammography in patients of average risk. Mammogram and follow-up ultrasound remain the best approach for routine screening, and a percutaneous biopsy is the most efficient follow-up for most indicators.

                      The major benefit of magnetic resonance imaging is also one of its drawbacks: it is able to detect lesions which are very very small (less than 10 mm) and allows you to view 70% more of a breast image in MRI  than conventional methods.This can lead to many unnecessary investigations. At screening, MRI can find many more “potential” lesions than mammography or ultrasound, but most of these turn out to be elements of normal tissue that are benign. In fact, the consensus opinion seems to be that women who are at ‘average‘ risk for breast cancer development should not be screened using MRI.

          The most compelling use of MRI is for the detection of malignancy in discovered lesions or masses. It is frequently used for women with breast cancer implants. And, it is used to distinguish scar tissue from potential lesions in post operative patients. Most of the time, however, MRI is used for clinical staging purposes for patients with confirmed malignant neoplasia, especially in patients with dense breast tissue.Magnetic resonance imaging is also frequently used for screening high risk patients with BRCA1 and BRCA2 genetic variants. Breast cancer screening with MRI is quite often now recommended for women who have an approximately 20-25% or greater lifetime risk of breast cancer development, and this would include women with a strong family history of breast or ovarian cancer, and women who were previously treated for Hodgkin disease.
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                            MRI is usually performedif we  have had a biopsy that’s positive for cancer, and  doctor needs more information about the extent of the disease. In certain situations, such as for women with high risk of breast cancer, breast MRI may be used with mammograms as a screening tool for detecting breast cancer.
A breast MRI is a safe procedure that doesn’t expose you to radiation. But as with other tests, a breast MRI has risks such as a risk of false-positive results, or a risk of reaction to the contrast dye used.