Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
Med Phys. 2013 Apr;40(4):041915. doi: 10.1118/1.4795758.
In the research and development of dedicated tomographic breast imaging systems, digital breast object models, also known as digital phantoms, are useful tools. While various digital breast phantoms do exist, the purpose of this study was to develop a realistic high-resolution model suitable for simulating three-dimensional (3D) breast imaging modalities. The primary goal was to design a model capable of producing simulations with realistic breast tissue structure.
The methodology for generating an ensemble of digital breast phantoms was based on imaging surgical mastectomy specimens using a benchtop, cone-beam computed tomography system. This approach allowed low-noise, high-resolution projection views of the mastectomy specimens at each angular position. Reconstructions of these projection sets were processed using correction techniques and diffusion filtering prior to segmentation into breast tissue types in order to generate phantoms.
Eight compressed digital phantoms and 20 uncompressed phantoms from which an additional 96 pseudocompressed digital phantoms with voxel dimensions of 0.2 mm(3) were generated. Two distinct tissue classification models were used in forming breast phantoms. The binary model classified each tissue voxel as either adipose or fibroglandular. A multivalue scaled model classified each tissue voxel as percentage of adipose tissue (range 1%-99%). Power spectral analysis was performed to compare simulated reconstructions using the breast phantoms to the original breast specimen reconstruction, and fits were observed to be similar.
The digital breast phantoms developed herein provide a high-resolution anthropomorphic model of the 3D uncompressed and compressed breast that are suitable for use in evaluating and optimizing tomographic breast imaging modalities. The authors believe that other research groups might find the phantoms useful, and therefore they offer to make them available for wider use.
在专用层析乳房成像系统的研究和开发中,数字乳房物体模型(也称为数字体模)是非常有用的工具。虽然存在各种数字乳房体模,但本研究的目的是开发一种适合模拟三维(3D)乳房成像方式的逼真高分辨率模型。主要目标是设计一种能够产生具有逼真乳房组织结构模拟的模型。
生成数字乳房体模集合的方法基于使用台式锥束 CT 系统对手术乳房切除术标本进行成像。这种方法允许在每个角度位置对乳房切除术标本进行低噪声、高分辨率的投影视图。在对这些投影集进行重建之前,使用校正技术和扩散滤波对其进行处理,然后对其进行分割成乳房组织类型,以生成体模。
生成了 8 个压缩数字体模和 20 个未压缩体模,从中又生成了 96 个具有 0.2mm(3)体素尺寸的额外伪压缩数字体模。两种不同的组织分类模型用于形成乳房体模。二值模型将每个组织体素分类为脂肪或纤维腺体。多值缩放模型将每个组织体素分类为脂肪组织的百分比(范围为 1%-99%)。对使用乳房体模进行模拟重建与原始乳房标本重建进行了功率谱分析,观察到拟合相似。
本文开发的数字乳房体模提供了一种 3D 未压缩和压缩乳房的高分辨率拟人模型,适用于评估和优化层析乳房成像方式。作者认为其他研究小组可能会发现这些体模有用,因此他们提供了更广泛的使用。