NOISE CONSIDERATIONS IN DUAL ENERGY COMPUTERIZED TOMOGRAPHY SCANNING
NOISE CONSIDERATIONS IN DUAL ENERGY COMPUTERIZED TOMOGRAPHY SCANNING
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DOI：
10.1118/1.594520
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发表时间：
1979-01-01
期刊：
影响因子：
--
通讯作者：
HILAL S K
中科院分区：
文献类型：
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作者：
KELCZ F;JOSEPH P M;HILAL S K
双能 CT [计算机断层扫描] 扫描（断层化学）先前被提出作为一种诊断方法，用于确定与组织元素组成相关的各种参数。研究了所提出的 2 种双能量扫描技术中固有的相对噪声：2 晶体技术和 2 kV 技术。在2晶体技术中，使用分体晶体探测器在高kV下的1次扫描期间同时获得高能和低能数据。 2 kV 技术需要使用不同的 kV 设置进行 2 次扫描。为了回顾利用扫描数据计算相关参数的 3 种常见方法，使用了构建的形式主义。该形式用于研究密度为未知参数的情况下CT图像噪声对测量精度的影响。 2 晶体技术获得的特殊数据中不可避免的重叠会导致信噪比比 2 kV 技术低得多； 2 kV 技术中高能束硬渗透的必要性是一个缺点；对于给定的 X 射线管热负荷，2 kV 技术的剂量较低。
Dual energy CT [computerized tomography] scanning (tomochemistry) was previously proposed as a diagnostic method for determining various parameters relating to the elemental composition of tissues. The relative noise inherent in 2 proposed techniques for dual energy scanning: a 2 crystal technique and a 2 kV technique was studied. In the 2 crystal technique, a split crystal detector is used to simultaneously obtain the high and low energy data during 1 scan at high kV. The 2 kV technique requires 2 scans taken with widely different kV settings. To review 3 common methods for utilizing the scan data to compute relevant parameters a constructed formalism is used. This formalism is used to study the influence of CT image noise on measurement precision in the case where densities are unknown parameters. Unavoidable overlap in the special data obtained by the 2 crystal technique results in a much lower signal-to-noise ratio than was obtained by the 2 kV technique; necessity for hard infiltration of the high energy beam in the 2 kV technique was a liability; and the dose for a given X-ray tube heat load is lower with the 2 kV technique.