【摘要】 目的:通过模拟和临床实际应用状态,测试3D全身显像方式PET/CT显像图像融合精度。方法:用测试模型及其配套的22Na固体点源,模拟人体宽度和厚度,采集点源PET/CT图像数据;然后将相同的点源置于检查床两测的床垫下,在检查床无负重和负重85kg时,分别采集PET/CT图像数据。重建图像后,在PET/CT融合图像的三个断层面分别寻找CT和PET点源图像的中心,测量二者中心偏差的mm数,即PET/CT图像融合精度。结果:PET和CT两种模态融合图像肉眼可见较明显的错位。模型点源PET/CT融合图像最大偏差为(4.25±0.26)mm、检查床无负重时为(3.96±0.26)mm,检查床负重85kg时为(5.36±0.26)mm。结论:本研究方法可以比较精确地测量PET/CT图像融合精度,并有效地指导PET/CT仪器的验收和故障检测等。更多还原

【Abstract】 Objective: The aim of this study was to find a way to measure the differences of the fusion images accurately on the 3D whole body PET/CT studies under the model simulating and patient clinical practise situation. Methods: The image fusion special model with 6 22Na solid point sources were imaged with Philips Gemini PET/CT for simulating the r-rays from the dif- ferent positions in the patient body.Then the same point sources were put under the pad of the patient bed for acquiring the 3D whole body PET/CT data synchronously with and without patient on the bed. Image fusion differences were evaluated visually, and the centers of the CT and PET images were found on the PET/CT fusion images respectively, after reconstrution and regis- tering. Then the distances between the two centers of CT and PET images were measure accurately by millimeter (mm). Re- sults:Obvious image fusion differences were inspected on all of the point sources PET/CT images.The maximum differences were (4.25±0.26) mm, (3.96 ± 0.26) mm and (5.36 ± 0.26) mm on the fusion images of the model, with and without patient on the bed,respectively. Conclusions: The fusion image differences maight be measured precisely with these methods, and it could also be used for the acceptance test and failure testing of PET/CT systems.更多还原