The use of compression during MR imaging of the breast to demonstrate elasticity variation between different tissues and lesions
Pretorius P., Moore N., Hayton P., Brady M.
Clinicians exploit the difference in the elastic properties of normal and abnormal breast tissues during physical examination. We performed a pilot study of breast compression during MR imaging to determine whether elasticity variations could aid in tissue discrimination. Eleven patients, referred for breast MR investigations, participated in the study. Compressed and uncompressed images of twenty breasts (2 unilateral and 9 bilateral) were acquired. Pathology detected by conventional MR criteria on the uncompressed images included one carcinoma and two fibroadenomas (confirmed histologically) and one cyst (confirmed on ultrasound). In nine breasts sufficient amounts of glandular tissue were available to compare the compressive strain values of glandular tissue to that of the whole breast (fat and glandular tissue). Glandular tissue in all nine breasts had lower strain values (average 0.265) - and therefore higher values of Young's modulus - than the whole breast (average 0.330). One fibroadenoma (0.093) and one cyst (0.149) had considerably lower strain values than the surrounding breast (0.311 and 0.312). The second fibroadenoma and the carcinoma were situated too close to the chest wall to be compressed. This pilot study suggests that assessment of elasticity variations on breast MR images can aid in tissue discrimination.