Fast three-dimensional dual echo dixon technique improves fat suppression in breast MRI.

PURPOSE

To compare qualitative and quantitative measures of the contrast-enhanced dual-echo Dixon technique with the commonly used standard three-dimensional (3D) gradient echo (spectrally selective fat suppression) technique (SS-FS) in breast MRI exams (bMRI).

MATERIALS AND METHODS

A total of 19 women, with prescheduled bMRI exam, were recruited to our study between 2006 and 2008. Dixon and standard SS-SF techniques were used on both breasts of each patient. Image quality was rated in five categories: fat suppression quality, fat suppression uniformity, lesion margin clarity, lesion visibility, and axillary visibility. For quantitative assessment, we calculated the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of lesion to breast, SNR efficiency, and CNR efficiency.

RESULTS

Of 19 patients evaluated, 13 had a primary breast malignancy and 6 had benign lesions or negative exams. Dixon images were rated higher in four of five qualitative categories (P < 0.0001) and required a shorter scan time. Dixon images yielded significantly higher SNR (43.8) and CNR (40.1) values than did 3DGRE images (SNR = 34.8, CNR = 25.3; P < 0.05). SNR efficiency (36.30) and CNR efficiency (33.79) values for Dixon images were also higher than were 3DGRE images (SNR efficiency =25.7, CNR efficiency = 19.1; P < 0.05).

CONCLUSION

Dixon images were superior to the standard SS-SF images in both qualitative and quantitative assessment of 19 bMRI exams. The Dixon technique could replace standard SS-SF technique in bMRI exam, after our findings have been confirmed in future studies with a larger sample size.