PET中散射的测量和校正

The measurement and correction of the scatter in PET

PET利用符合探测技术除探测两个同时发生的方向相反的 5 11ke V的发射湮灭光子外 ,由于散射辐射的存在 ,同样也探测到与湮灭光子能量相似的散射光子 ,增加了信噪比和错误事件的计数率 ,结果产生赝像。因此 ,了解散射对 PET测量的影响 ,掌握散射及散射份数的测量和散射的校正方法 。

The coincidence technique employed in positron emission tomography (PET) to detect the two simultaneously, emitted annihilation photons of 511 keV that travel at a 180° angle to each other. Because of the scattered radiation, the scattered photons were also detected by the coincidence technique in PET. PET images uncorrected for scatter give inaccurate image data and, in addition, the scatter contribution could give rise to signal to noise ratio (SNR) and could produce highly structured errors or artifacts in the images. So, to understand of the effects of the scatter on PET imaging, and to master the measured and corrected methods of the scatter will improve the quality of image and accurately measure the biological parameters of the radiophamaceutical in vivo.