BACKGROUND 18F-2-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) plays an important role in the diagnosis, evaluation and treatment of childhood epilepsy. The selection of appropriate acquisition and reconstruction parameters, however, can be challenging with the introduction of advanced hardware and software functionalities. OBJECTIVE To quantify the diagnostic performance of a block-sequential regularized expectation maximization (BSREM) tool and reduced effective counts in brain PET/CT for pediatric epilepsy patients on a digital silicon photomultiplier system. MATERIALS AND METHODS We included 400 sets of brain PET/CT images from 25 pediatric patients (0.5-16 years old) in this retrospective study. Patient images were reconstructed with conventional iterative techniques or BSREM with varied penalization factor (β), at varied acquisition time (45 s, 90 s, 180 s, 300 s) to simulate reduced count density. Two pediatric nuclear medicine physicians reviewed images in random order - blinded to patient, reconstruction method and imaging time - and scored technical quality (noise, spatial resolution, artifacts), clinical quality (image quality of the cortex, basal ganglia and thalamus) and overall diagnostic satisfaction on a 5-point scale. RESULTS Reconstruction with BSREM improved quality and clinical scores across all count levels, with the greatest benefits in low-count conditions. Image quality scores were greatest at 300-s acquisition times with β=500 (overall; noise; artifacts; image quality of the cortex, basal ganglia and thalamus) or β=200 (spatial resolution). No statistically significant difference in the highest graded reconstruction was observed between imaging at 180 s and 300 s with an appropriately implemented penalization factor (β=350-500), indicating that a reduction in dose or acquisition time is feasible without reduction in diagnostic satisfaction. CONCLUSION Clinical evaluation of pediatric 18F-FDG brain PET image quality was shown to be diagnostic at reductions of count density by 40% using BSREM with a penalization factor of β=350-500. This can be accomplished while maintaining confidence of achieving a diagnostic-quality image.

中文翻译：

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使用数字PET / CT对小儿18F-FDG脑PET重建和采集时间的临床评估。

背景技术18 F-2-氟-2-脱氧葡萄糖（FDG）正电子发射断层扫描（PET）在儿童癫痫的诊断，评估和治疗中起着重要的作用。但是，随着高级硬件和软件功能的引入，选择合适的采集和重建参数可能会面临挑战。目的通过数字硅光电倍增管系统，量化块序正则化期望最大化（BSREM）工具的诊断性能，并减少小儿癫痫患者脑部PET / CT的有效计数。材料与方法在这项回顾性研究中，我们纳入了来自25例儿科患者（0.5-16岁）的400套大脑PET / CT图像。使用传统的迭代技术或具有不同惩罚因子（β）的BSREM重建患者图像，在不同的采集时间（45 s，90 s，180 s，300 s）下模拟减少的计数密度。两名儿科核医学医师以随机顺序查看图像-对患者不了解，重建方法和成像时间-并对技术质量（噪声，空间分辨率，伪影），临床质量（皮质，基底神经节和丘脑的图像质量）和总体评分5分制的诊断满意度。结果使用BSREM进行重建可改善所有计数水平的质量和临床评分，在低计数条件下具有最大的益处。在300 s的采集时间中，图像质量得分最高，其中β= 500（总体；噪声；伪影；皮质，基底神经节和丘脑的图像质量）或β= 200（空间分辨率）。在180 s和300 s成像与适当实施的惩罚因子（β= 350-500）之间，在最高分级的重建过程中没有观察到统计学上的显着差异，表明减少剂量或获取时间是可行的，而不会降低诊断满意度。结论儿科18F-FDG脑部PET图像质量的临床评估显示，使用BSREM的计数密度降低40％（惩罚因子为β= 350-500）具有诊断意义。这可以在保持实现诊断质量图像的信心的同时完成。结论儿科18F-FDG脑部PET图像质量的临床评估显示，使用BSREM的计数密度降低40％（惩罚因子为β= 350-500）具有诊断意义。这可以在保持实现诊断质量图像的信心的同时完成。结论儿科18F-FDG脑部PET图像质量的临床评估显示，使用BSREM的计数密度降低40％（惩罚因子为β= 350-500）具有诊断意义。这可以在保持实现诊断质量图像的信心的同时完成。