Avid Radiopharmaceuticals, Inc,, 3711 Market Street, 7th Floor, Philadelphia, PA 19104, USA.
EJNMMI Res. 2014 Jan 8;4(1):4. doi: 10.1186/2191-219X-4-4.
Florbetapir is one of several 18F-labeled amyloid plaque imaging tracers for positron emission tomography (PET). As the bio-distribution and radiation dose of PET tracers in human research are important for estimating the relative risks and benefits, a study was conducted to obtain this information on florbetapir.
Nine cognitively normal subjects (six females and three males, age 58 ± 10 years, weight 81 ± 17 kg) received an intravenous bolus injection of 395 ± 27.9 MBq of florbetapir, and whole-body emission scans were performed over approximately 6 h. Computed tomography scans were acquired for attenuation correction. Volumes of interest (VOIs) for source organs including the brain, liver, lung, heart wall, and vertebrae were defined on the PET images. The VOIs of the gallbladder, urinary bladder, and large and small intestines were also defined. Using reference man organ volumes (ICRP 30), total activity was calculated per organ for each time point. The resultant time-activity curves (TACs) were fitted with constrained exponentials. Kinetic data were entered into OLINDA/EXM software to calculate dose estimates; the dynamic urinary bladder and ICRP 30 GI tract models were employed. The effective dose (ED) for each subject was estimated from the acquired data using the adult model.
The mean ED determined for nine healthy volunteers was 18.60 ± 4.26 μSv/MBq or 6.88 mSv for a 370-MBq dose. The organs that received the highest radiation absorbed doses were the gallbladder, upper large intestine, small intestine, liver, and urinary bladder at 143.0 ± 80.20, 74.50 ± 34.20, 65.50 ± 29.60, 64.40 ± 22.10, and 27.10 ± 11.70 μSv/MBq, respectively.
The ED for florbetapir has been calculated for nine healthy volunteers. At a dose of 370 MBq florbetapir, the total average ED is approximately 6.88 mSv.
氟[18F]标记的淀粉样斑块成像示踪剂之一是氟[18F]标记的淀粉样斑块成像示踪剂，用于正电子发射断层扫描（PET）。由于在人体研究中 PET 示踪剂的生物分布和辐射剂量对于估计相对风险和益处非常重要，因此进行了这项研究以获取有关氟[18F]标记的氟贝他哌的信息。
9 名认知正常的受试者（6 名女性和 3 名男性，年龄 58 ± 10 岁，体重 81 ± 17 公斤）接受静脉推注 395 ± 27.9 MBq 的氟[18F]标记的氟贝他哌，并进行了大约 6 小时的全身发射扫描。采集计算机断层扫描（CT）扫描以进行衰减校正。在 PET 图像上定义了包括大脑、肝脏、肺、心脏壁和脊椎在内的源器官的感兴趣体积（VOI）。还定义了胆囊、膀胱、大、小肠的 VOI。使用参考人器官体积（ICRP 30），计算了每个时间点每个器官的总活动。拟合所得时间-活性曲线（TAC）用约束指数。将动力学数据输入 OLINDA/EXM 软件以计算剂量估算值；使用动态膀胱和 ICRP 30GI 模型。使用成人模型从获得的数据中估算每个受试者的有效剂量（ED）。
对 9 名健康志愿者的平均 ED 测定值为 18.60 ± 4.26 μSv/MBq 或 370-MBq 剂量的 6.88 mSv。吸收辐射剂量最高的器官是胆囊、大肠上部、小肠、肝脏和膀胱，分别为 143.0 ± 80.20、74.50 ± 34.20、65.50 ± 29.60、64.40 ± 22.10 和 27.10 ± 11.70 μSv/MBq。
已经为 9 名健康志愿者计算了氟[18F]标记的氟贝他哌的 ED。在 370 MBq 氟[18F]标记的氟贝他哌剂量下，总平均 ED 约为 6.88 mSv。
