Abstract #2097

The Effect of B1 Inhomogeneity on Enhancement Ratio Measurements Using DCE-MRI of the Breast at 3T.

C A. Azlan^1,2, Trevor S. Ahearn¹, Gordon D. Waiter¹, Scott I. Semple³, Fiona J. Gilbert¹, Thomas W. Redpath¹

¹Aberdeen Biomedical Imaging Centre, University of Aberdeen, Aberdeen, Scotland, UK; ²Department of Biomedical Imaging, University of Malaya, Kuala Lumpur, Malaysia; ³Department of Medical Physics, University of Edinburgh, Edinburgh, Scotland, UK

B1 inhomogeneity is a major drawback of 3T MRI and may affect the accuracy of enhancement ratio (ER) measurement after DCE-MRI of the breast. To simulate the effect of B1 inhomogeneity on DCE-MRI, T1-weighted FLASH images of gel phantoms were acquired using a range of flip angles. We show that there is an underestimation of ER, which increases with ER, as B1 decreases. Clinically 100% enhancement is frequently used as a threshold for malignancy. At this level we show that for a 54% B1 field there is a 20% underestimation of ER. This underestimation could reduce the specificity/sensitivity of DCE-MRI of the breast.