A cost-effective high-performance ceramic garnet scintillator for PET

用于 PET 的经济高效的高性能陶瓷石榴石闪烁体

• 批准号: 8554763
• 负责人: Simon R Cherry
• 金额: $ 36.27万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-30 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8554763
• 关键词: Animal Experimentation; Animals; Area; Attention; Beryllium; Biomedical Research; Categories; Ceramics; Clinic; Clinical; Clinical Research; Communities; Coupled; Data; Dependence; Deposition; Detection; Development; Diagnostics Research; Dimensions; Discipline of Nuclear Medicine; Elements; Ensure; Evaluation; Floods; Goals; Growth; Hybrids; Image; Imaging Techniques; Imaging technology; Indium; Knowledge; Lead; Length; Light; Lutetium; Measurement; Measures; Mechanics; Methods; Output; Performance; Photons; Polishes; Positron-Emission Tomography; Process; Production; Property; Protocols documentation; Radiation; Reading; Research; Resolution; Sampling; Shapes; Signal Transduction; Silicon; Staging; Structure; Surface; System; Techniques; Technology; Temperature; Thick; Time; Tube; Visible Radiation; Work; attenuation; base; bismuth germanium oxide; clinical application; cold temperature; cost; cost effective; cost shifting; density; design; detector; flexibility; improved; indexing; instrumentation; magnetic field; molecular imaging; photomultiplier; scale up

DESCRIPTION (provided by applicant): The performance of positron emission tomography (PET) scanners is dictated, to a large extent, by the properties and dimensions of the scintillator elements used to form the detectors. Critical properties of the scintillator material include its brightness, its stopping power and its decay time. Because of its fundamental importance in nuclear medicine imaging, and the limitations of current scintillator materials, research into new detector materials remains active. In this proposal, we study the potential for a rare-earth garnet, (GdxLu1-x)3(GayAl1-y)5O12:Ce (abbreviated as GLuGAG) to be used as a scintillator in PET detectors. It has an unprecedented combination of properties, including high stopping power (attenuation length 1.3 cm at 511 keV), high light yield (~66,000 photons/MeV deposited) and a fast decay time (~40 ns), and unlike most other very bright scintillators, it is not moisture sensitive. Because it has a cubic crystal structure, it also can be fabricated using ceramic techniques. This allows the material to be made at lower temperatures and more quickly than conventional scintillators grown as single crystals. It also offers tantalizing possibilities for directly fabricating scintillator elements in the desired size and shape with no cutting. Ceramic scintillators therefore have the potential to result in much lower cost materials compared with traditional scintillators. Several years of development and characterization work on GLuGAG has been completed and at this stage small samples of materials with excellent properties can be reliably fabricated using ceramic techniques. The goals of this proposal are to i) fine-tune the composition of GLuGAG to minimize the decay time and maximize the light output; ii) to fully characterize the scintillation properties of GLuGAG; iii) to scale up the volume of material produced such that it is large enough for a complete PET block detector unit; iv) to investigate directly fabricating elements in the size and shape required; v) to characterize the performance of GLuGAG elements of appropriate sizes for PET applications in terms of energy resolution and timing resolution; vi) and to build and evaluate pairs of complete PET detector modules for comparison against the performance of existing commercial detectors in terms of spatial resolution, efficiency, energy and timing resolution. We also will explore more advanced PET detector designs with dual-ended readout for depth- encoding, and read out of GLuGAG scintillator arrays using large-area silicon photomultiplier technology. The combination of GLuGAG's outstanding scintillation properties, and the ability to fabricate it with high transparency using ceramic approaches (a feature not shared by any other scintillator with plausible density for PET applications) offers tremendous potential to favorably and significantly shift the cost/performance trade-off in PET detector design, thereby impacting all applications of PET from the clinic through small-animal research.

描述（由申请人提供）：正电子发射断层扫描（PET）扫描仪的性能在很大程度上取决于闪烁体的特性和尺寸 用于形成探测器的元件。闪烁体材料的关键特性包括其亮度、阻止能力和衰减时间。由于其在核医学成像中的根本重要性以及当前闪烁体材料的局限性，对新探测器材料的研究仍然活跃。在本提案中，我们研究了稀土石榴石 (GdxLu1-x)3(GayAl1-y)5O12:Ce（缩写为 GLuGAG）在 PET 探测器中用作闪烁体的潜力。它具有前所未有的特性组合，包括高阻止本领（在 511 keV 时衰减长度为 1.3 厘米）、高光产额（约 66,000 个光子/MeV 沉积）和快速衰减时间（约 40 纳秒），并且与大多数其他非常明亮的闪烁体不同，它不含水分 敏感的。由于它具有立方晶体结构，因此也可以使用陶瓷技术制造。与传统的单晶闪烁体相比，这使得该材料可以在更低的温度下更快地制造。它还为直接制造所需尺寸和形状的闪烁体元件而无需切割提供了诱人的可能性。因此，与传统闪烁体相比，陶瓷闪烁体有可能生产出成本低得多的材料。 GLuGAG 数年的开发和表征工作已经完成，现阶段可以使用陶瓷技术可靠地制造具有优异性能的材料小样品。该提案的目标是 i) 微调 GLuGAG 的组成可最大限度地减少衰减时间并最大限度地提高光输出； ii) 充分表征 GLuGAG 的闪烁特性； iii) 扩大生产材料的体积，使其足够大以容纳完整的 PET 块检测器单元； iv) 研究直接制造所需尺寸和形状的元件； v) 表征用于 PET 应用的适当尺寸的 GLuGAG 元件在能量分辨率和时间分辨率方面的性能； vi) 并构建和评估成对的完整 PET 探测器模块，以便与现有商业探测器在空间分辨率、效率、能量和时间分辨率方面的性能进行比较。我们还将探索更先进的 PET 探测器设计，具有用于深度编码的双端读出器，并使用大面积硅光电倍增器技术读出 GLuGAG 闪烁体阵列。 GLuGAG 出色的闪烁特性与使用陶瓷方法制造高透明度的能力（PET 应用中具有合理密度的任何其他闪烁体所不具备的功能）相结合，提供了巨大的潜力，可以有利且显着地改变 PET 探测器设计中的成本/性能权衡，从而影响 PET 从临床到小动物研究的所有应用。