采集时间、注射药量与正电子发射体层摄影术图像质量  

The key factors of the quality in PET images:acquisition time and injection dose

作　　者：王新强[1] 于彤[1] 川玲[1] 赵文锐[1] 方庭正[1] 王升[1] 梁英魁[1] 

机构地区：[1]海军总医院核医学科,北京100048

出　　处：《海军总医院学报》2010年第1期3-4,共2页Journal of Naval General Hospital of PLA

摘　　要：目的通过对患者体内18F-氟脱氧葡萄糖(18F-FDG)剂量、采集持续时间和正电子发射体层摄影术(PET)图像质量进行相关性分析,深入了解获得高质量诊断图像的必要条件,指导图像采集工作。方法采用GE公司Discovery ST型正电子发射体层摄影术/计算机体层摄影术(PET/CT)仪对9例患者进行容积成像协议(VIP)3D采集。使用VIP程序提取2、2.5、3 min原始数据序列进行图像重建,使用CT对PET图象进行衰减校正。两位有经验的核医学科医生通过视觉判断法对图像质量进行分级。选择没有肝脏病变的PET图像,将感兴趣区(ROI)置于肝脏面积较大的横断面和冠状面图层的肝区,计算ROI内的放射性计数、标准摄取值(SUV)。使用SPSS 10.0软件包对结果进行相关性分析。结果采集9例患者的VIP原始数据进行重建,得到Ⅰ级图像11个,Ⅱ级图像13个,Ⅲ级图像3个。放射性计数中位值:Ⅰ级图像5 308个,Ⅱ级图像3 683个,Ⅲ级图像3 245个。Spearman相关性分析结果显示肝区计数与图像质量分级间呈负相关,r=-0.769,P=0.001(2-tailed)。结论受检者体内足够的放射性计数以及适当的图像采集时间是获得高质量PET图像的前提和保证,且两者相辅相成。Objective To study the relationship of the factors such as acquisition time and injection dose with the quantity of the PET images. Methods Nine patients were examined by GE Discovery ST PET/CT scanner,and PET reconstruction was used for 2,2.5 and 3 min per position in volume imaging protocol（VIP） 3D mode. The PET images were attenuation corrected by CT image. Two salted nuclear medicine physicians classified the images as three quality levels by visual assessment. To evaluate the image quality quantificationally,the radioactivity counts and standard uptake values（SUV） in the region of interest（ROIs）of the axial and coronal images of normal livers were analyzed relatively with SPSS 10.0 software. Results After reconstruction of the data, nine series of images （twenty seven images） acquisited for 2,2.5 and 3 min per position were obtained. There were eleven level Ⅰ images, thirteen level Ⅱ images and three level Ⅲ images. The middle radioactivity counts were 5 308,3 683 and 3 245 respectively. Spearman relative analyze showed that counts in the ROI of livers were negative correlative with the image quality levels （r=-0. 769,P=0. 001 （2- tailed））. Conclusion Enough radioactivity count and proper acquisition time are the premise of high PET image quality and supplement each other.

关 键 词：正电子发射体层摄影术 图像质量 注射剂量 采集时间 

分 类 号：R817[医药卫生—影像医学与核医学]