Mammographic imaging with a small format CCD-based digital cassette: Physical characteristics of a clinical system
Mammographic imaging with a small format CCD-based digital cassette: Physical characteristics of a clinical system
复制标题
DOI：
10.1118/1.1286720
复制
发表时间：
2000-08-01
期刊：
影响因子：
3.8
通讯作者：
D'Orsi, CJ
中科院分区：
文献类型：
--
作者：
Vedantham, S;Karellas, A;D'Orsi, CJ
研究了基于临床电荷耦合器件（CCD）的成像仪（Senovision, GE Medical Systems, Milwaukee， WI）用于小视场数字乳房x线摄影的物理特性。成像仪采用MinR 2000(TM) （Eastman Kodak Company, Rochester， NY）闪烁体，由1:1光纤耦合到前置照明的61X61 mm CCD，工作像素间距为30微米。采用调制传递函数（MTF）、噪声功率谱（NPS）、检测量子效率（DQE）和噪声等效量子（NEQ）等客观标准进行评价。结果表明，极限空间分辨率（10% MTF）为10 cy/mm。使用28 kVp， 4.5 cm Lucite硬化的Mo-Mo光谱光束，当前原型的测量DQE在8.2 mR的曝光下接近零空间频率时接近40%，在1.1 mR的低曝光下下降到接近28%，经过适当的校准和软件校正后，检测器元件的不均匀性和电子增益变化并不显著。成像仪的响应是线性的，在测试的曝光条件下没有表现出信号饱和。(C) 2000年美国医学物理学家协会。[s0094 - 2405(00) 01308 - 0]。
The physical characteristics of a clinical charge coupled device (CCD)-based imager (Senovision, GE Medical Systems, Milwaukee, WI) for small-field digital mammography have been investigated. The imager employs a MinR 2000(TM) (Eastman Kodak Company, Rochester, NY) scintillator coupled by a 1:1 optical fiber to a front-illuminated 61X61 mm CCD operating at a pixel pitch of 30 microns. Objective criteria such as modulation transfer function (MTF), noise power spectrum (NPS), detective quantum efficiency (DQE), and noise equivalent quanta (NEQ) were employed for this evaluation. The results demonstrated a limiting spatial resolution (10% MTF) of 10 cy/mm. The measured DQE of the current prototype utilizing a 28 kVp, Mo-Mo spectrum beam hardened with 4.5 cm Lucite is similar to 40% at close to zero spatial frequency at an exposure of 8.2 mR, and decreases to similar to 28% at a low exposure of 1.1 mR. Detector element nonuniformity and electronic gain variations were not significant after appropriate calibration and software corrections. The response of the imager was linear and did not exhibit signal saturation under tested exposure conditions. (C) 2000 American Association of Physicists in Medicine. [S0094-2405(00)01308-0].