CAJ | 학술논문

PET/CT图像的呼吸运动伪影严重影响胸腹部肿瘤的诊断与治疗计划的制定.现有的伪影校正方法大都涉及呼吸门控设备和四维CT的使用,不仅给测试带来不便,还让患者遭受大剂量的CT照射从而对其造成额外伤害.为此.采用正弦振动来模拟呼吸运动,通过对仿真和体模图像倒谱的Radon变换来估算呼吸运动的幅度和方向,然后分别采用维纳滤波、约束最小二乘法和Richardson-Lucy迭代算法.根据估计的运动参数对伪影图像进行反卷积并比较它们的去伪影结果.仿真与体模实验结果均显示出模拟呼吸运动参数估计和伪影校正的良好结果,且方法安全、简便而经济,有望用于常规采集的静态PET图像呼吸伪影校正.
PET/CT도상적호흡운동위영엄중영향흉복부종류적진단여치료계화적제정.현유적위영교정방법대도섭급호흡문공설비화사유CT적사용,불부급측시대래불편,환양환자조수대제량적CT조사종이대기조성액외상해.위차.채용정현진동래모의호흡운동,통과대방진화체모도상도보적Radon변환래고산호흡운동적폭도화방향,연후분별채용유납려파、약속최소이승법화Richardson-Lucy질대산법.근거고계적운동삼수대위영도상진행반권적병비교타문적거위영결과.방진여체모실험결과균현시출모의호흡운동삼수고계화위영교정적량호결과,차방법안전、간편이경제,유망용우상규채집적정태PET도상호흡위영교정.
The respiratory motion leads to significant motion artifacts of the positron emission tomography (PET) image,thus influencing diagnoses and treatments in the radiation oncology.The existing approaches to correct motion artifacts involve using gating devices and/or four-dimensional (4-D) computed tomography (CT).However,they have the disadvantages of high CT dose and high computational burden.Hence,a sinusoid vibra-tion model is presented to simulate the respiratory motion.The motion extent and the direction are derived from the Radon transform of the cepstrum of the blurred image.Then,two typical deconvolution algorithms,i.e.,Wiener filter (WF) and the Richardson-Lucy (RL) algorithms are used to eliminate the motion blur according to the estimated parameters and their de-blurring results are compared.Experiments on both synthetic and phantom images show good performance of the presented model for identifying vibration modeled respiration motion and re-ducing the motion blur.The method has advantages of safety,convenience,and economy.And it is promising to correct the motion artifacts of the non-gated PET image.