Intravoxel incoherent motion (IVIM) and non-Gaussian diffusion MRI of the lactating breast

Highlights • Breastfeeding significantly affects IVIM and non-Gaussian diffusion parameters. • The distribution of ADC0 values becomes more heterogeneous after breastfeeding. • Care needs to be taken in interpreting DWI data in lactating breasts.
Purpose To investigate the effect of breastfeeding on IVIM and non-Gaussian diffusion MRI in the breast. Materials and methods An IRB approved prospective study enrolled seventeen volunteers (12 in lactation and 5 with post-weaning, range 31–43 years; mean 35.4 years). IVIM (fIVIM and D*) and non-Gaussian diffusion (ADC0 and K) parameters using 16 b values, plus synthetic apparent diffusion coefficients (sADCs) from 2 key b values (b = 200 and 1500 s/mm2) were calculated using regions of interest. ADC0 maps of the whole breast were generated and their contrast patterns were evaluated by two independent readers using retroareolar and segmental semi-quantitative scores. To compare the diffusion and IVIM parameters, Wilcoxon signed rank tests were used between pre- and post-breastfeeding and Mann-Whitney tests were used between post-weaning and pre- or post-breastfeeding. Results ADC0 and sADC values significantly decreased post-breastfeeding (1.90 vs. 1.72 × 10−3 mm2/s, P