MRI-Guided Minimally Invasive Breast Procedures

Abstract

During the last decade, MR mammography has been successfully tested as an adjunct imaging modality to mammography and ultrasound of the breast. Lesions that cannot be detected in mammography and ultrasound are shown with high sensitivity and in realistic extent but specificity is still poor. However, the high sensitivity of MR alone is not satisfactory if histology cannot be obtained. Therefore MR mammography should only be performed if there is the opportunity to verify findings in histology in a selected small group of patients in which the lesions cannot be biopsied otherwise or follow-up appears not indicated. MR mammography should therefore only be offered by institutions that can offer MR biopsy or that are in close contact with a site that can offer this type of biopsy. Prior to any thought about MR biopsy, the diagnostic MR examination on which the indication is based should be checked for quality. This includes perfect timing (5th to 12th day after the beginning of menstruation), cessation of hormone replacement therapy 4–6 weeks prior to the exam, and the choice of established contrast media with appropriate dosage. Mammography, ultrasound, and MR exams (preferably in digital format and not simply print-outs) should be available, checked, and correlated, and focused ultrasound should be tried with the intent for biopsy prior to MR indication.