Adenosine-stress dynamic myocardial perfusion imaging using 128-slice dual-source CT: optimization of the CT protocol to reduce the radiation dose.
The aim of this study was to compare the radiation dose and image quality of different adenosine-stress dynamic myocardial perfusion CT protocols using a 128-slice dual-source computed tomography (DSCT) scanner. We included 330 consecutive patients with suspected coronary artery disease. Protocols employed the following dynamic scan parameters: protocol I, a 30-s scan with a fixed tube current (FTC, n = 172); protocol II, a 30-s scan using an automatic tube current modulation (ATCM) technique (n = 108); protocol III, a 14-s scan using an ATCM (n = 50). To determine the scan interval for protocol III, we analyzed time-attenuation curves of 26 patients with myocardial perfusion who had been scanned using protocol I or II. The maximum attenuation difference between normal and abnormal myocardium occurred at 18.0 s to 30.3 s after initiation of contrast injection. Myocardial perfusion images of FTC and ATCM were of diagnostic image quality based on visual analysis. The mean radiation dose associated with protocols I, II, and III was 12.1 ± 1.6 mSv, 7.7 ± 2.5 mSv, and 3.8 ± 1.3 mSv, respectively (p < 0.01). Use of a dose-modulation technique and a 14-s scan duration for adenosine-stress CT enables significant dose reduction while maintaining diagnostic image quality.
Department of Radiology and Cardiovascular Imaging Center, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, Korea.
Sung Mok
SM
Kim
Yoo Na
YN
Kim
Yeon Hyeon
YH
Choe
D000241:Adenosine; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003326:Coronary Circulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011237:Predictive Value of Tests; D011829:Radiation Dosage; D013997:Time Factors; D014665:Vasodilator Agents; D055815:Young Adult
D014665:Vasodilator Agents; D000241:Adenosine