Boston Raymond C, Schnall Mitchell D, Englander Sarah A, Landis J Richard, Moate Peter J
School of Veterinary Medicine, New Bolton Center, University of Pennsylvania, Kenneth Square, PA 19348, USA.
Magn Reson Imaging. 2005 May;23(4):591-9. doi: 10.1016/j.mri.2005.02.006.
Mammographic breast density has been correlated with breast cancer risk. Estimation of the volumetric composition of breast tissue using three-dimensional MRI has been proposed, but accuracy depends upon the estimation methods employed. The use of segmentation based on T1 relaxation rates allows quantitative estimates of fat and parenchyma volume, but is limited by partial volume effects. An investigation employing phantom breast tissue composed of various combinations of chicken breast (to represent parenchyma) and cooking fats was carried out to elucidate the factors that influence MRI T1 histograms. Using the phantoms, T1 histograms and their known fat and parenchyma composition, a logistic distribution function was derived to describe the apportioning of the T1 histogram to fat and parenchyma. This function and T1 histograms were then used to predict the fat and parenchyma content of breasts from 14 women. Using this method, the composition of the breast tissue in the study population was as follows: fat 69.9+/-22.9% and parenchyma 30.1+/-22.9%.
乳腺钼靶密度与乳腺癌风险相关。有人提出使用三维磁共振成像（MRI）来估计乳腺组织的体积组成，但准确性取决于所采用的估计方法。基于T1弛豫率的分割方法可对脂肪和实质体积进行定量估计，但受部分容积效应限制。本研究使用由鸡胸肉（代表实质）和烹饪脂肪的各种组合构成的乳腺组织模型，以阐明影响MRI T1直方图的因素。利用这些模型、T1直方图及其已知的脂肪和实质组成，推导出一个逻辑分布函数来描述T1直方图在脂肪和实质之间的分配情况。然后使用该函数和T1直方图来预测14名女性乳房的脂肪和实质含量。采用这种方法，研究人群中乳腺组织的组成如下：脂肪69.9±22.9%，实质30.1±22.9%。
