A prototype MR insertable brain PET using tileable GAPD arrays
A prototype MR insertable brain PET using tileable GAPD arrays
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DOI：
10.1118/1.4793754
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发表时间：
2013-04-01
期刊：
影响因子：
3.8
通讯作者：
Park, Hyun-wook
中科院分区：
文献类型：
--
作者：
Hong, Key Jo;Choi, Yong;Park, Hyun-wook
目的：本研究的目的是开发一种原型磁共振（MR）兼容的正电子发射断层扫描（PET），可以插入到MR成像仪，并允许同时PET和MR成像的人脑。本文报道了作者的原型脑PET系统在3-T磁共振成像（MRI）系统中使用新开发的基于盖革模式雪崩光电二极管（GAPD）的PET探测器、长柔性扁平电缆、具有高复用比的位置解码器电路和基于现场可编程门阵列的模数转换器板的数字信号处理的初步结果。方法：构建了一个具有72个环形探测器模块的脑PET，并安装在3-T MRI中。每个PET模块均由耦合到可拼接GAPD的掺铈正硅酸镥钇（LYSO）晶体组成。使用3 m长的扁平电缆将GAPD输出电荷信号传输到前置放大器。LYSO和GAPD位于MR孔内，所有电子器件位于MR孔外。PET探测器的性能进行了研究内外的MRI，和MR图像质量进行了评估，并没有PET system.Results：PET探测器的性能时，在MRI内操作的MR图像采集过程中，能量分辨率和计数率没有显着变化，除了轻微的退化，从4.2到4.6 ns的时间分辨率增加。在3-T MRI中采集热棒和霍夫曼脑体模的同步PET/MR图像。在热棒PET图像中分辨直径低至3.5 mm的棒。霍夫曼脑模型中的白色和灰质之间的活动分布模式被很好地成像。热棒和霍夫曼脑幻影的同时获得的标准序列的MR图像上观察到没有任何明显的伪影，虽然MR图像质量需要一些improvement.Conclusions：这些结果表明，PET和MR图像的同时采集是可行的，使用MR插入PET在这项研究中开发。(C)2013年美国医学物理学家协会。[http：//dx.doi.org/10.1118/1.4793754]
Purpose: The aim of this study was to develop a prototype magnetic resonance (MR)-compatible positron emission tomography (PET) that can be inserted into a MR imager and that allows simultaneous PET and MR imaging of the human brain. This paper reports the initial results of the authors' prototype brain PET system operating within a 3-T magnetic resonance imaging (MRI) system using newly developed Geiger-mode avalanche photodiode (GAPD)-based PET detectors, long flexible flat cables, position decoder circuit with high multiplexing ratio, and digital signal processing with field programmable gate array-based analog to digital converter boards.Methods: A brain PET with 72 detector modules arranged in a ring was constructed and mounted in a 3-T MRI. Each PET module was composed of cerium-doped lutetium yttrium orthosilicate (LYSO) crystals coupled to a tileable GAPD. The GAPD output charge signals were transferred to preamplifiers using 3 m long flat cables. The LYSO and GAPD were located inside the MR bore and all electronics were positioned outside the MR bore. The PET detector performance was investigated both outside and inside the MRI, and MR image quality was evaluated with and without the PET system.Results: The performance of the PET detector when operated inside the MRI during MR image acquisition showed no significant change in energy resolution and count rates, except for a slight degradation in timing resolution with an increase from 4.2 to 4.6 ns. Simultaneous PET/MR images of a hot-rod and Hoffman brain phantom were acquired in a 3-T MRI. Rods down to a diameter of 3.5 mm were resolved in the hot-rod PET image. The activity distribution patterns between the white and gray matter in the Hoffman brain phantom were well imaged. The hot-rod and Hoffman brain phantoms on the simultaneously acquired MR images obtained with standard sequences were observed without any noticeable artifacts, although MR image quality requires some improvement.Conclusions: These results demonstrate that the simultaneous acquisition of PET and MR images is feasible using the MR insertable PET developed in this study. (C) 2013 American Association of Physicists in Medicine. [http://dx.doi.org/10.1118/1.4793754]