Additional application of ¹H-spectroscopic (3D-MRSI) and diffusion-weighted magnetic resonance imaging (MRI) in breast MRI at 3 T: is there a diagnostic value in comparison with high temporal and spatial resolution morphologic and dynamic MRI in patients with breast lesions?

Introduction

To assess the diagnostic accuracy of ¹H-spectroscopic (3D-MRSI) and diffusion-weighted magnetic resonance imaging (DWI) in comparison with high-temporal and spatial resolution dynamic MRI in patients with breast lesions at 3 T.

Materials and methods

Thirty-six patients were examined on a 3 T system. The MRI protocol included: contrast-enhanced (CE) coronal volumetric interpolated breathhold examination with high-temporal resolution (isotropic 1.7 mm, time of acquisition (TA) 11.7 seconds, 17 measurements); coronal magnetization prepared rapid gradient echo at expected maximum CE (1 mm isotropic, TA 2.03 minutes), repeated coronal volumetric interpolated breathhold examination, diffusion-weighted imaging using a twice-refocused singleshot echo planar imaging sequence with inversion recovery fat-saturation employing four b values (TA 4.48 minutes), 3D-MRSI (10 × 10 × 10 mm³; TA 11 minutes). The lesion morphology and CE kinetics were assessed. Regions of interest for suspicious areas were evaluated for elevated choline levels and decreased apparent diffusion coefficient values as a marker of malignancy.

Results

Sixty-five lesions were detected in 36 patients. CE-MRI determined 11 lesions, DWI 11 lesions and 3D-MRSI 11 lesions (one false positive, one false negative) as malignant. CE-MRI determined 48 lesions, DWI 54 lesions and 3D-MRSI 49 lesions as benign. 3D-MRSI was not applicable in five prepectoral lesions. CE-MRI determined six lesions as indifferent, which were benign with DWI and 3D-MRSI.

Conclusion

The performance of dynamic MRI and additional DWI and 3D-MRSI is possible within reasonable scan time, and additional DWI and 3D-MRSI aid the differentiation of breast lesions with indifferent morphology and/or CE kinetics.