Accuracy of fully automated, quantitative, volumetric measurement of the amount of fibroglandular breast tissue using MRI: correlation with anthropomorphic breast phantoms

Abstract

To demonstrate the accuracy of fully automated, quantitative, volumetric measurement of the amount of fibroglandular breast tissue (FGT), using MRI, and to investigate the impact of different MRI sequences using anthropomorphic breast phantoms as the ground truth. In this study, 10 anthropomorphic breast phantoms that consisted of different known fractions of adipose and protein tissue, which closely resembled normal breast parenchyma, were developed. Anthropomorphic breast phantoms were imaged with a 1.5 T unit (Siemens, Avantofit) using an 18-channel breast coil. The sequence protocol consisted of an isotropic Dixon sequence (Di), an anisotropic Dixon sequence (Da), and T 3D FLASH sequences with and without fat saturation (T1). Fully automated, quantitative, volumetric measurement of FGT for all anthropomorphic phantoms and sequences was performed and correlated with the amounts of fatty and protein components in the phantoms as the ground truth. Fully automated, quantitative, volumetric measurements of FGT with MRI for all sequences ranged from 5.86 to 61.05% (mean 33.36%). The isotropic Dixon sequence yielded the highest accuracy (median 0.51%-0.78%) and precision (median range 0.19%) compared with anisotropic Dixon (median 1.92%-2.09%; median range 0.55%) and T -weighted sequences (median 2.54%-2.46%; median range 0.82%). All sequences yielded good correlation with the FGT content of the anthropomorphic phantoms. The best correlation of FGT measurements was identified for Dixon sequences (Di, R = 0.999; Da, R = 0.998) compared with conventional T -weighted sequences (R = 0.971). MRI yields accurate, fully automated, quantitative, volumetric measurements of FGT, an increasingly important and sensitive imaging biomarker for breast cancer risk. Compared with conventional T sequences, Dixon-type sequences show the highest correlation and reproducibility for automated, quantitative, volumetric FGT measurements using anthropomorphic breast phantoms as the ground truth.

Reproducible automated breast density measure with no ionizing radiation using fat‐water decomposition MRI

“…In comparison, we quantify breast density based on the fraction of fibroglandular tissue and actual water content in each voxel, after correcting the fat-water signal bias, enabling a more reliable estimation. Third, the previous breast density measurements were not directly comparable with MD, and Wengert et al 34,36 along with other previous studies based on T 1weighted MRI [19][20][21] showed that their MRI-derived breast density measurements were systematically lower than MD. However, MD is still the most widely accepted method for breast density evaluation in clinical practice and clinical research, and a large number of studies reported their findings using MD, including clinical trials.…”

“…This study also exhibits other, methodological strengths compared with the previously published studies that developed fat‐water decomposition MRI‐based breast density measurements . First, previous studies lacked the validation of their semi‐ or fully‐automated breast segmentation against ground truth manual segmentation.…”

“…This study also exhibits other, methodological strengths compared with the previously published studies that developed fat-water decomposition MRI-based breast density measurements. 9,23,[34][35][36] First, previous studies lacked the validation of their semi-or fully-automated breast segmentation against ground truth manual segmentation. In our method, we quantitatively validate our fully automated breast segmentation with manual segmentation using a Dice index; moreover, we demonstrate that automated segmentation leads to more reproducible breast density measures.…”

T1‐based sensing of mammographic density using single‐sided portable NMR

“…Finally, the results presented here raise a case for investigating the ability of T 1 maps to quantify mammographic density clinically. Sensitivity of T 1 ‐weighted images to MD is already well‐recognized in breast imaging . Acquisition of the full T 1 recovery curve is not routine in clinical settings because of imaging time constraints.…”

Looking beyond the mammogram to assess mammographic density: A narrative review

“…The amount of FGT calculated from this sequence is highly correlated with that calculated from standard T 1 -weighted imaging using the FC algorithm (r Spearman = 0.93 [26]), but has not yet been compared to MD measured by mammogram. A recent comparative phantom-based study of automated volumetric quantification of FGT has found that both Dixon and T 1 -weighted sequences exhibit very good precision and accuracy when compared to the ground truth [123].…”