Quantification of breast density with spectral mammography based on a scanned multi-slit photon-counting detector: a feasibility study.
Quantification of breast density with spectral mammography based on a scanned multi-slit photon-counting detector: a feasibility study.
复制标题
基于扫描多缝光子计数探测器的光谱乳腺 X 线摄影术对乳腺密度的量化：可行性研究。
DOI：
10.1088/0031-9155/57/15/4719
复制
发表时间：
2012
影响因子：
3.5
通讯作者：
Molloi,Sabee
中科院分区：
文献类型：
--
作者：
Ding,Huanjun;Molloi,Sabee
简单而准确的乳腺密度测量对于了解其在乳腺癌风险模型中的影响至关重要。采用计算机模拟和物理体模研究，研究了光子计数能谱乳腺X射线摄影系统量化乳腺体积密度的可行性。一个计算机模拟模型涉及多能谱从钨阳极X射线管和硅基光子计数探测器已被评估乳腺密度定量。品质因数（FOM）被定义为双能量图像相对于平均腺体剂量的平方根的信噪比，被选择用于优化成像协议，在管电压和分裂能量方面。采用扫描式多狭缝光子计数能谱乳腺X线摄影系统，利用均匀厚度的腺体和脂肪等效体模，采用双能量分解法定量测量乳腺密度。设计了四种不同的体模研究来评估该技术的准确性，每种研究都解决了体模配置中的一个特定变量，包括厚度、密度、面积和形状。除了用于双能量分解的标准校准拟合函数之外，还提出了一种改进的拟合函数，该函数将用于成像任务的管电压作为双能量分解的第三变量。对于平均尺寸为4.5 cm厚的乳房，FOM在管电压为46 kVp和分裂能量为24 keV的情况下最大化。为了与当前临床筛查检查中使用的管电压（1032 kVp）一致，建议最佳分裂能量为22 keV，其提供大于最佳值90%的FOM。在实验研究中，使用标准校准函数估计所有四个体模研究的乳腺密度定量的均方根（RMS）误差约为1.54%。将管电压作为校准中的一个变量整合的改良拟合函数的结果表明，所有四项研究的RMS误差约为1.35%。当前研究的结果表明，光子计数能谱乳腺X射线摄影系统可能用于准确定量体积乳腺密度，RMS误差小于2%，使用拟议的双能量成像技术。
A simple and accurate measurement of breast density is crucial for the understanding of its impact in breast cancer risk models. The feasibility to quantify volumetric breast density with a photon-counting spectral mammography system has been investigated using both computer simulations and physical phantom studies. A computer simulation model involved polyenergetic spectra from a tungsten anode x-ray tube and a Si-based photon-counting detector has been evaluated for breast density quantification. The figure-of-merit (FOM), which was defined as the signal-to-noise ratio of the dual energy image with respect to the square root of mean glandular dose, was chosen to optimize the imaging protocols, in terms of tube voltage and splitting energy. A scanning multi-slit photon-counting spectral mammography system has been employed in the experimental study to quantitatively measure breast density using dual energy decomposition with glandular and adipose equivalent phantoms of uniform thickness. Four different phantom studies were designed to evaluate the accuracy of the technique, each of which addressed one specific variable in the phantom configurations, including thickness, density, area and shape. In addition to the standard calibration fitting function used for dual energy decomposition, a modified fitting function has been proposed, which brought the tube voltages used in the imaging tasks as the third variable in dual energy decomposition. For an average sized 4.5 cm thick breast, the FOM was maximized with a tube voltage of 46 kVp and a splitting energy of 24 keV. To be consistent with the tube voltage used in current clinical screening exam (∼ 32 kVp), the optimal splitting energy was proposed to be 22 keV, which offered a FOM greater than 90% of the optimal value. In the experimental investigation, the root-mean-square (RMS) error in breast density quantification for all four phantom studies was estimated to be approximately 1.54% using standard calibration function. The results from the modified fitting function, which integrated the tube voltage as a variable in the calibration, indicated a RMS error of approximately 1.35% for all four studies. The results of the current study suggest that photon-counting spectral mammography systems may potentially be implemented for an accurate quantification of volumetric breast density, with an RMS error of less than 2%, using the proposed dual energy imaging technique.