Departments of Imaging and Medicine, Cedars-Sinai Medical Center, Los Angeles, California Siemens Healthcare Molecular Imaging, Knoxville, Tennessee
Departments of Imaging and Medicine, Cedars-Sinai Medical Center, Los Angeles, California.
J Nucl Med. 2015 Dec;56(12):1876-81. doi: 10.2967/jnumed.115.164285. Epub 2015 Sep 24.
A novel PET radiotracer, Flurpiridaz F 18, has undergone phase II clinical trial evaluation as a high-resolution PET cardiac perfusion imaging agent. In a subgroup of patients imaged with this agent, we assessed the feasibility and benefit of simultaneous correction of respiratory and cardiac motion.
In 16 patients, PET imaging was performed on a 4-ring scanner in dual cardiac and respiratory gating mode. Four sets of data were reconstructed with high-definition reconstruction (HD•PET): ungated and 8-bin electrocardiography-gated images using 5-min acquisition, optimal respiratory gating (ORG)-as developed for oncologic imaging-using a narrow range of breathing amplitude around end-expiration level with 35% of the counts in a 7-min acquisition, and 4-bin respiration-gated and 8-bin electrocardiography-gated images (32 bins in total) using the 7-min acquisition (dual-gating, using all data). Motion-frozen (MF) registration algorithms were applied to electrocardiography-gated and dual-gated data, creating cardiac-MF and dual-MF images. We computed wall thickness, wall/cavity contrast, and contrast-to-noise ratio for standard, ORG, cardiac-MF, and dual-MF images to assess image quality.
The wall/cavity contrast was similar for ungated (9.3 ± 2.9) and ORG (9.5 ± 3.2) images and improved for cardiac-MF (10.8 ± 3.6) and dual-MF images (14.8 ± 8.0) (P < 0.05). The contrast-to-noise ratio was 22.2 ± 9.1 with ungated, 24.7 ± 12.2 with ORG, 35.5 ± 12.8 with cardiac-MF, and 42.1 ± 13.2 with dual-MF images (all P < 0.05). The wall thickness was significantly decreased (P < 0.05) with dual-MF (11.6 ± 1.9 mm) compared with ungated (13.9 ± 2.8 mm), ORG (13.1 ± 2.9 mm), and cardiac-MF images (12.1 ± 2.7 mm).
Dual (respiratory/cardiac)-gated perfusion imaging with Flurpiridaz F 18 is feasible and improves image resolution, contrast, and contrast-to-noise ratio when MF registration methods are applied.
一种新型的正电子发射断层扫描放射性示踪剂 Flurpiridaz F 18 已在 II 期临床试验中作为一种高分辨率的正电子发射断层扫描心脏灌注成像剂进行了评估。在使用该示踪剂进行成像的患者亚组中，我们评估了同时校正呼吸和心脏运动的可行性和益处。
在 16 名患者中，在 4 环扫描仪上以双心脏和呼吸门控模式进行 PET 成像。使用高清晰度重建（HD•PET）重建了四组数据：无门控和 8 -bin 心电图门控图像，采集时间为 5 分钟；使用窄呼吸幅度（接近呼气末期水平）和 35%的计数进行最佳呼吸门控（ORG）——用于肿瘤成像——采集时间为 7 分钟；使用 7 分钟采集进行 4-bin 呼吸门控和 8-bin 心电图门控图像（总共 32 个 bin）（双门控，使用所有数据）。应用运动冻结（MF）配准算法对心电图门控和双门控数据进行处理，创建心脏 MF 和双 MF 图像。我们计算了标准、ORG、心脏 MF 和双 MF 图像的壁厚度、壁/腔对比度和对比噪声比，以评估图像质量。
未门控（9.3 ± 2.9）和 ORG（9.5 ± 3.2）图像的壁/腔对比度相似，而心脏 MF（10.8 ± 3.6）和双 MF（14.8 ± 8.0）图像的壁/腔对比度提高（P < 0.05）。未门控的对比噪声比为 22.2 ± 9.1，ORG 为 24.7 ± 12.2，心脏 MF 为 35.5 ± 12.8，双 MF 为 42.1 ± 13.2（均 P < 0.05）。与未门控（13.9 ± 2.8 毫米）、ORG（13.1 ± 2.9 毫米）和心脏 MF（12.1 ± 2.7 毫米）相比，双 MF（11.6 ± 1.9 毫米）图像的壁厚度显著降低（P < 0.05）。
当应用 MF 配准方法时，Flurpiridaz F 18 的双（呼吸/心脏）门控灌注成像具有可行性，并提高了图像分辨率、对比度和对比噪声比。
