Takahashi T, Nakagawa M, Yoshida M, Takeuchi H
Central Research Laboratory, Hitachi, Ltd., Tokyo, Japan.
Med Phys. 1992 Sep-Oct;19(5):1161-6. doi: 10.1118/1.596919.
A detailed analysis of the effects of temperature changes, over time and between array elements, on the generation of circular artifacts in images produced by x-ray computed tomography was reported. We give formulas for calculating--according to the x-ray energy, detector sensitivity, and observed image quality (contrast and spatial resolution)--the maximum offset temperature coefficient and maximum gain temperature coefficient that will allow circular-artifact-free imaging. A temperature-controlled and insulated solid-state x-ray detector array, consisting of Gd2O2S:Pr,Ce,F ceramic scintillators coupled to crystal Si pin-photodiodes and designed to meet the requirements for these coefficients, produced high-resolution artifacts-free CT images of a phantom head.
报道了对随时间以及阵列元件之间温度变化对X射线计算机断层扫描所产生图像中圆形伪影生成的影响进行的详细分析。我们给出了根据X射线能量、探测器灵敏度和观察到的图像质量（对比度和空间分辨率）来计算最大偏移温度系数和最大增益温度系数的公式，这些系数能实现无圆形伪影成像。一种温度受控且绝缘的固态X射线探测器阵列，由与晶体硅pin光电二极管耦合的Gd2O2S:Pr,Ce,F陶瓷闪烁体组成，并设计为满足这些系数的要求，该阵列生成了无高分辨率伪影的头部模型CT图像。
