ABSTRACT
Objective To explore the main influence factors(heart rate,rotation speed,and reconstruction algorithm)on the image quality of coronary artery with 40 mm VCT(64-detector row helical CT)using a pulsating cardiac phantom.Methods An adjustable pulsating cardiac phantom(GE) containing predetermined simulated coronary arteries was scanned using a 40 mm VCT(GE LightSpeed CT) with cardiac pulsating rates of 40,45,50,55,60,65,70,75,80,85,90,95,100,105,110,and 115 beats per minute(bpm).The variable rotation speeds technique of 0.35 s,0.40 s,and 0.45 s were used, respectively.The raw data were reconstructed using both one-sector and multi-sector reconstruction algorithm at optimal window of the R-R interval.The image quality score(IQS)was evaluated by two radiologists according to the same evaluation standard of reformated image.The correlation between heart rate(HR), roation speed,reconstruction algorithm,and IQS were analyzed.The IQS as independent variable and the HR,rotation speed,reconstruction algorithm as dependent variables were analyzed by multiple linear regression analysis.Restllts The heart rate and the reconstruction algorithm had significant influence on IQS.The rotation speed(0.35s,0.40s,and 0.45s)didn't have significant influence on IQS.There was linear regression relationship between heart rate,reconstruction algorithm and IQS(P