CONTRAST-ENHANCED MRI OF THE BREAST - ACCURACY, VALUE, CONTROVERSIES,SOLUTIONS

Objective: Contrast-enhanced MRI of the breast has been one of the mos t controversial areas of MRI. Even though most investigators have, in selected indications, been able to improve accuracy by the additional use of contrast-enhanced MRI; its abuse has been feared not only becau se of increased costs for imaging, but also because of increased biops y rates caused by false positive calls and because of errors caused by insufficient standardisation. In this article an overview is given of the present knowledge about contrast-enhanced MRI of the breast. Fact ors that influence the accuracy and reproducibility of contrast-enhanc ed MRI are analysed. Method: Factors that influence accuracy include: (1) technical factors that influence accuracy, e.g. slice thickness (p artial volume effect), motion reduction, reduction of (cardiac) artifa cts, dosage of contrast agent, choice of pulse sequence and echotime, and choice of the method for elimination of fat signal. (2) Hormonal f actors (timing of the examination with reference to the menstrual cycl e, hormonal replacement therapy). They influence accuracy and must be taken into account. (3) Interpretation guidelines-their choice influen ces sensitivity and specificity mostly inversely and the use of inform ation from conventional imaging appears necessary. (4) Patient selecti on influences accuracy for statistical and for biological reasons. Res ults: Based on the present literature and on the experiences gathered in six German universities (> 12 000 examinations) an excellent sensit ivity (> 98%) can be achieved for the combination of mammography and M RI. However, specificity strongly varies with the indications. Recomme nded indications include examination of breasts with impaired evaluati on due to severe scarring, after silicon implants and in the dense bre ast. exclusion of multicentricity and search for primary tumor. Indica tions under investigation include high risk patients and strictly sele cted problem cases. Conclusion: If appropriately applied and used for selected indications, contrast-enhanced MRI may allow a significant di agnostic gain. In order to take advantage of the full potentials of co ntrast-enhanced MRI the development of commercially available biopsy c oils is essential. (C) 1997 Elsevier Science Ireland Ltd.