Abstract:Objective: To explore the effect of sampling interval on normal gastric perfusion by revolution CT. Methods: Twenty-eight volunteers without gastric disease were studied using revolution CT scanner. Fourteen volunteers(group A) were scanned with standard continuous perfusion, and other volunteers(group B) were scanned with intermittent perfusion. Two groups of perfusion scanning were performed with axial scan mode and Z axis coverage of 160 mm. Group A collected perfusion images 25 times with sampling intervals of 2 s(exposure time of 0.5 s, interval time of 1.5 s), and the total scan time was 50 s. Group B obtained arterial phase image with spiral scanning mode at 15 s after 8 times perfusion. The conversion time from helical to axial scan mode and exposure time was about 12~16.2 s. And then another 13 times of perfusion data were collected, with a total scan time of 50~54.2 s. Three regions of interest were placed in gastric wall of greater and lesser curvature. The acquired data were used for calculation and analysis by a CT perfusion software package to measure 8 parameters: blood flow(BF), blood volume(BV), mean transit time (MTT), time to peak(TP), positive enhancement integral(PEI), mean slope of interest(MSI), IRF and Tmax. Radiation dosage was also collected. Perfusion parameters in the greater and lesser curvature of stomach in different groups were compared. Result: BV((12.83±4.30), (18.44±4.39) mL/(min·100 g)) and BF((61.54±10.13), (64.99±13.77) mL/100 g) in the greater curvature were statistically higher than those of lesser curvature both in group A and B, with P values of 0.027, 0.004, 0.002 and 0.000. But the rest perfusion parameters(MTT, TP, MSI, PEI, IRF, Tmax) didn’t show significant difference. Between the two groups of BV and PEI in the greater and lesser curvature, differences were statistically significant(P=0.002, 0.004, 0.017, 0.032). And only in the lesser curvature there was a significant difference for MTT and Tmax, but no significant difference was found in the greater curvature. Values of group A were lower than those in group B. And there were no difference for BF, TP, MSI and IRF between two groups. Effect dosage of intermittent perfusion was reduced by 15.41% compared with continuous perfusion. Conclusion: Sampling interval of gastric perfusion on revolution CT has an effect on BV, MTT, PEI and Tmax perfusion parameters, but not on BF, TP, MSI and IRF values. BV and BF values are different between greater curvature and lesser curvature.
刘晓冬,刘爱连,刘静红,刘义军,孙美玉,李 烨,赵 莹,方 鑫,袁 刚. Revolution CT全胃灌注扫描时间间隔对正常胃壁灌注数据的影响[J]. 中国临床医学影像杂志, 2017, 28(6): 425-429.
LIU Xiao-dong, LIU Ai-lian, LIU Jing-hong, LIU Yi-jun, SUN Mei-yu, LI Ye, ZHAO Ying, FANG Xin, YUAN Gang. Influence of sampling interval on whole stomach CT perfusion for normal gastric wall. JOURNAL OF CHINA MEDICAL IMAGING, 2017, 28(6): 425-429.