Performance Characteristics of Long Axial Field-of-View PET Scanners with Axial Gaps.
Performance Characteristics of Long Axial Field-of-View PET Scanners with Axial Gaps.
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DOI：
10.1109/trpms.2020.3027257
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发表时间：
2021-05
影响因子：
4.4
通讯作者：
Karp JS
中科院分区：
文献类型：
--
作者：
Daube-Witherspoon ME;Viswanath V;Werner ME;Karp JS
长(>；60厘米)轴向视野(LAFOV)PET系统的引入显示了其在临床和研究应用的潜力。LAFOV扫描仪价格昂贵，因此有兴趣设计具有更长轴向覆盖范围的系统，同时通过引入探测器间隙来降低成本。我们使用PennPET Explorer(-cm AFOV原型)上的测量结果和长达143厘米的扫描仪的模拟来评估扫描仪的性能，其中轴向间隙通过改变每个环中的探测器行数来引入。移除探测器会降低总灵敏度，并导致轴向噪声分布不均匀。轴向分辨率显示从AFOV边缘到中心的损失很小(<；0.5 mm)，即使是具有不受限制接受角度的143厘米AFOV扫描仪也是如此。与没有间隙的系统相比，大的轴向间隙的存在增加了AFOV的轴向分辨率和对比度恢复的可变性。轴向间隙越小，表现出的变化就越小。结果表明，间隙不大于探测器环宽度的一半的设计可能是首选的，尽管在性能和AFOV之间权衡的扫描器设计的最佳选择将取决于其预期用途。
The introduction of long (>60 cm) axial field-of-view (LAFOV) PET systems has shown their potential for clinical and research applications. LAFOV scanners are expensive, so there is interest in designing systems with longer axial coverage while mitigating cost by introducing detector gaps. We used measurements on the PennPET Explorer (64-cm AFOV prototype) and simulations of scanners up to 143-cm long to assess scanner performance with axial gaps introduced by varying the number of detector rows in each ring. Removing detectors reduces the total sensitivity and results in a non-uniform axial noise profile. Axial resolution shows small (<0.5 mm) loss from the edge of the AFOV to the center, even for a 143-cm AFOV scanner with an unrestricted acceptance angle. The presence of large axial gaps increases the variability in axial resolution and contrast recovery across the AFOV compared to a system without gaps. More modest axial gaps show less variable behavior. The results suggest that designs where the gap is no larger than one-half of the width of a detector ring may be preferred, although the optimal choice of scanner design with the trade-offs of performance and AFOV will depend on its intended usage.