Diffusion-weighted imaging: Effects of intravascular contrast agents on apparent diffusion coefficient measures of breast malignancies at 3 tesla

作者：Nguyen Vicky T; Rahbar Habib; Olson Matthew L; Liu Cheng Liang; Lehman Constance D; Partridge Savannah C^*

来源：Journal of Magnetic Resonance Imaging, 2015, 42(3): 788-800.

DOI：10.1002/jmri.24844

• magnetic resonance imaging
• diffusion-weighted imaging
• apparent diffusion coefficient
• gadolinium
• breast cancer

BackgroundTo determine whether apparent diffusion coefficient (ADC) measures of breast lesions at 3 Tesla (T) are affected by gadolinium administration.
MethodsThe study included 19 patients who underwent 3T MRI. Diffusion-weighted imaging (DWI) was acquired with b=0, 100, and 800 s/mm(2) before and after a dynamic contrast-enhanced (DCE) sequence. ADC values were measured for each lesion and normal fibroglandular tissue. Pre- and postcontrast ADC measures were compared by Wilcoxon signed-rank test, and differences between groups were compared by Mann-Whitney U test; P<0.05 was considered statistically significant.
ResultsThere was no significant difference in pre- and postcontrast ADC measured at b=0, 100, 800 s/mm(2) for malignancies (median change: -0.4%, -0.01 x 10(-3) mm(2)/s, P=0.40), but there was a slight increase in postcontrast ADC in normal tissue (+1.6%, +0.04 x 10(-3) mm(2)/s, P=0.0006). Findings were similar for both lesions (-0.4%, -0.01 x 10(-3) mm(2)/s, P=0.54) and normal tissue (+1.5%, +0.03 x 10(-3) mm(2)/s, P=0.002) with ADC measured at b=0,800 and also at b=100, 800 s/mm(2) (lesions: +0.9%, +0.01 x 10(-3) mm(2)/s, P=0.71; normal tissue: +1.8%, +0.03 x 10(-3) mm(2)/s, P=0.005). For lesions, results were not affected by lesion size, type (mass versus nonmass enhancement), mean initial enhancement, late enhancement, or delayed enhancement rate on DCE-MRI (P>0.05 for all). Normal tissue showed some trends with greater progressive enhancement rates and higher late enhancement levels correlating with greater increase in postcontrast ADC (P=0.09 for both).
ConclusionOur results show that breast lesion ADC measures using our approach were not significantly altered following DCE-MRI at 3T, suggesting DWI and DCE-MRI can be performed in any order without affecting diagnostic criteria. However, influences of contrast on ADC measures in normal breast tissue were observed and require further investigation. J. Magn. Reson. Imaging 2015;42:788-800.

• 出版日期2015-9