Li Hongdi, Badawi Ramsey D, Cherry Simon R, Fontaine Kathryn, He Liuchun, Henry Shannan, Hillmer Ansel T, Hu Lingzhi, Khattar Nikkita, Leung Edwin K, Li Tiantian, Li Yusheng, Liu Chi, Liu Peng, Lu Zhenrui, Majewski Stanislaw, Matuskey David, Morris Evan D, Mulnix Tim, Omidvari Negar, Samanta Suranjana, Selfridge Aaron, Sun Xishan, Toyonaga Takuya, Volpi Tommaso, Zeng Tianyi, Jones Terry, Qi Jinyi, Carson Richard E
United Imaging Healthcare North America, Houston, Texas.
University of California, Davis, Davis, California.
J Nucl Med. 2024 Aug 1;65(8):1320-1326. doi: 10.2967/jnumed.124.267767.
The collaboration of Yale, the University of California, Davis, and United Imaging Healthcare has successfully developed the NeuroEXPLORER, a dedicated human brain PET imager with high spatial resolution, high sensitivity, and a built-in 3-dimensional camera for markerless continuous motion tracking. It has high depth-of-interaction and time-of-flight resolutions, along with a 52.4-cm transverse field of view (FOV) and an extended axial FOV (49.5 cm) to enhance sensitivity. Here, we present the physical characterization, performance evaluation, and first human images of the NeuroEXPLORER. Measurements of spatial resolution, sensitivity, count rate performance, energy and timing resolution, and image quality were performed adhering to the National Electrical Manufacturers Association (NEMA) NU 2-2018 standard. The system's performance was demonstrated through imaging studies of the Hoffman 3-dimensional brain phantom and the mini-Derenzo phantom. Initial F-FDG images from a healthy volunteer are presented. With filtered backprojection reconstruction, the radial and tangential spatial resolutions (full width at half maximum) averaged 1.64, 2.06, and 2.51 mm, with axial resolutions of 2.73, 2.89, and 2.93 mm for radial offsets of 1, 10, and 20 cm, respectively. The average time-of-flight resolution was 236 ps, and the energy resolution was 10.5%. NEMA sensitivities were 46.0 and 47.6 kcps/MBq at the center and 10-cm offset, respectively. A sensitivity of 11.8% was achieved at the FOV center. The peak noise-equivalent count rate was 1.31 Mcps at 58.0 kBq/mL, and the scatter fraction at 5.3 kBq/mL was 36.5%. The maximum count rate error at the peak noise-equivalent count rate was less than 5%. At 3 iterations, the NEMA image-quality contrast recovery coefficients varied from 74.5% (10-mm sphere) to 92.6% (37-mm sphere), and background variability ranged from 3.1% to 1.4% at a contrast of 4.0:1. An example human brain F-FDG image exhibited very high resolution, capturing intricate details in the cortex and subcortical structures. The NeuroEXPLORER offers high sensitivity and high spatial resolution. With its long axial length, it also enables high-quality spinal cord imaging and image-derived input functions from the carotid arteries. These performance enhancements will substantially broaden the range of human brain PET paradigms, protocols, and thereby clinical research applications.
耶鲁大学、加利福尼亚大学戴维斯分校与联影医疗合作，成功研发出NeuroEXPLORER，这是一款专门用于人类大脑的正电子发射断层显像（PET）仪，具有高空间分辨率、高灵敏度，并内置三维相机用于无标记连续运动追踪。它具有高相互作用深度和飞行时间分辨率，以及52.4厘米的横向视野（FOV）和扩展的轴向视野（49.5厘米）以提高灵敏度。在此，我们展示NeuroEXPLORER的物理特性、性能评估及首批人体图像。按照美国国家电气制造商协会（NEMA）NU 2 - 2018标准，对空间分辨率、灵敏度、计数率性能、能量和时间分辨率以及图像质量进行了测量。通过对霍夫曼三维脑模体和迷你德伦佐模体的成像研究展示了该系统的性能。展示了来自一名健康志愿者的初始F - FDG图像。采用滤波反投影重建，对于径向偏移1厘米、10厘米和20厘米，径向和切向空间分辨率（半高宽）平均分别为1.64毫米、2.06毫米和2.51毫米，轴向分辨率分别为2.73毫米、2.89毫米和2.93毫米。平均飞行时间分辨率为236皮秒，能量分辨率为10.5%。NEMA灵敏度在中心处为46.0千计数每秒每兆贝可，在10厘米偏移处为47.6千计数每秒每兆贝可。在视野中心实现了11.8%的灵敏度。在58.0千贝可/毫升时，峰值噪声等效计数率为1.31兆计数每秒，在5.3千贝可/毫升时散射分数为36.5%。在峰值噪声等效计数率下的最大计数率误差小于5%。在3次迭代时，NEMA图像质量对比恢复系数在4.0:1的对比度下，从74.5%（10毫米球体）到92.6%（37毫米球体）不等，背景变化范围从3.1%到1.4%。一张人脑F - FDG图像示例展示出非常高的分辨率，捕捉到了皮质和皮质下结构的复杂细节。NeuroEXPLORER具有高灵敏度和高空间分辨率。凭借其长轴向长度，它还能够实现高质量的脊髓成像以及来自颈动脉的图像衍生输入函数。这些性能提升将极大地拓宽人类大脑PET范式、方案以及临床研究应用的范围。
