Robert Normand, Komljenovic Philip T, Rowlands J A
Canadian Heart Research Centre, Toronto, Ontario, Canada.
Med Phys. 2002 May;29(5):736-47. doi: 10.1118/1.1470205.
A method to significantly reduce the exposure area product in fluoroscopy using a pre-patient region-of-interest (ROI) attenuator is presented. The attenuator has a thin central region and a gradually increasing thickness away from the center. It is shown that the unwanted brightening artifact caused by the attenuator can be eliminated by attenuating the low spatial frequencies in the detected image using digital image processing techniques. An investigation of the best image processing method to correct for the presence of the attenuator is undertaken. The correction procedure selected is suitable for use with real-time image processors and the ROI attenuator can be permitted to move during image acquisition. Images of an anthropomorphic chest phantom acquired in the presence of the ROI attenuator using an x-ray image intensifier/video chain are corrected to illustrate the clinical feasibility of our approach.
提出了一种使用患者前感兴趣区域（ROI）衰减器显著减少荧光透视中曝光面积乘积的方法。该衰减器具有薄的中心区域，且厚度从中心向外逐渐增加。结果表明，通过使用数字图像处理技术衰减检测图像中的低空间频率，可以消除由衰减器引起的不必要的亮斑伪影。对校正衰减器存在的最佳图像处理方法进行了研究。所选择的校正程序适用于实时图像处理器，并且在图像采集期间可以允许ROI衰减器移动。使用X射线图像增强器/视频链在存在ROI衰减器的情况下采集的拟人化胸部体模图像经过校正，以说明我们方法的临床可行性。
