A Lower-Cost High-Resolution LYSO Detector Development for Positron Emission Mammography (PEM).
A Lower-Cost High-Resolution LYSO Detector Development for Positron Emission Mammography (PEM).
复制标题
用于正电子发射乳腺 X 线摄影 (PEM) 的低成本高分辨率 LYSO 探测器开发。
DOI：
10.1109/tns.2009.2030193
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发表时间：
2009
影响因子：
1.8
通讯作者：
Wong,Wai-Hoi
中科院分区：
文献类型：
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作者：
Ramirez,RocioA;Zhang,Yuxuan;Liu,Shitao;Li,Hongdi;Baghaei,Hossain;An,Shaohui;Wang,Chao;Jan,Meei-Ling;Wong,Wai-Hoi
在正电子发射层析成像应用的光电倍增管-象限共享（PQS）几何结构中，每个PMT由四个块共享，每个检测器块光学耦合到四个圆形PMT。虽然这种设计降低了高分辨率PET系统的成本，但当相机由方形块组成的探测器面板组成时，PMT在探测器面板边缘的敏感窗口有一半未使用。我们的目标是开发一种LYSO探测器面板，最大限度地减少pmt的未使用部分，用于低成本，高分辨率和高灵敏度的正电子发射乳房x线摄影（PEM）相机。我们修改了PQS设计，在面板边缘使用细长块，在内部区域使用方形块。对于长码块，采用对称和非对称的反射模式，实现PQS和pmt半共享（PHS）安排，以获得合适的解码。不对称块体的填充率为96.3%，对称块体的填充率为95.5%。这两个块都具有出色的解码能力，所有晶体都清晰地识别出来，非对称晶体为156，对称晶体为144，峰谷比分别为3.0和2.3。非对称块体的平均能量分辨率为14.2%，对称块体的平均能量分辨率为13.1%。采用改进的PQS几何形状和不对称块设计，减少了探测器面板边缘未使用的PMT区域，从而增加了视场和整体检测灵敏度，并最大限度地减少了胸壁附近未检测到的乳房区域。这种探测器的设计和使用常规的圆形PMT使得构建成本更低、高分辨率和高灵敏度的PEM相机成为可能。
In photomultiplier-quadrant-sharing (PQS) geometry for positron emission tomography applications, each PMT is shared by four blocks and each detector block is optically coupled to four round PMTs. Although this design reduces the cost of high-resolution PET systems, when the camera consists of detector panels that are made up of square blocks, half of the PMT's sensitive window remains unused at the detector panel edge. Our goal was to develop a LYSO detector panel which minimizes the unused portion of the PMTs for a low-cost, high-resolution, and high-sensitivity positron emission mammography (PEM) camera. We modified the PQS design by using elongated blocks at panel edges and square blocks in the inner area. For elongated blocks, symmetric and asymmetrical reflector patterns were developed and PQS and PMT-half-sharing (PHS) arrangements were implemented in order to obtain a suitable decoding. The packing fraction was 96.3% for asymmetric block and 95.5% for symmetric block. Both of the blocks have excellent decoding capability with all crystals clearly identified, 156 for asymmetric and 144 for symmetric and peak-to-valley ratio of 3.0 and 2.3 respectively. The average energy resolution was 14.2% for the asymmetric block and 13.1% for the symmetric block. Using a modified PQS geometry and asymmetric block design, we reduced the unused PMT region at detector panel edges, thereby increased the field-of-view and the overall detection sensitivity and minimized the undetected breast region near the chest wall. This detector design and using regular round PMT allowed building a lower-cost, high-resolution and high-sensitivity PEM camera.