title: Radiation dose reduction for coronary artery calcium scoring at 320-detector CT with adaptive iterative dose reduction 3D.
abstract: To assess the possibility of reducing the radiation dose for coronary artery calcium (CAC) scoring by using adaptive iterative dose reduction 3D (AIDR 3D) on a 320-detector CT scanner. Fifty-four patients underwent routine- and low-dose CT for CAC scoring. Low-dose CT was performed at one-third of the tube current used for routine-dose CT. Routine-dose CT was reconstructed with filtered back projection (FBP) and low-dose CT was reconstructed with AIDR 3D. We compared the calculated Agatston-, volume-, and mass scores of these images. The overall percentage difference in the Agatston-, volume-, and mass scores between routine- and low-dose CT studies was 15.9, 11.6, and 12.6%, respectively. There were no significant differences in the routine- and low-dose CT studies irrespective of the scoring algorithms applied. The CAC measurements of both imaging modalities were highly correlated with respect to the Agatston- (r = 0.996), volume- (r = 0.996), and mass score (r = 0.997; p < 0.001, all); the Bland-Altman limits of agreement scores were -37.4 to 51.4, -31.2 to 36.4 and -30.3 to 40.9%, respectively, suggesting that AIDR 3D was a good alternative for FBP. The mean effective radiation dose for routine- and low-dose CT was 2.2 and 0.7 mSv, respectively. The use of AIDR 3D made it possible to reduce the radiation dose by 67% for CAC scoring without impairing the quantification of coronary calcification.
authors.affiliation: Department of Diagnostic Radiology, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan, sa104@rg8.so-net.ne.jp.
authors.forename: Fuminari
authors.initials: F
authors.lastname: Tatsugami
authors.forename: Toru
authors.initials: T
authors.lastname: Higaki
authors.forename: Wataru
authors.initials: W
authors.lastname: Fukumoto
authors.forename: Yoko
authors.initials: Y
authors.lastname: Kaichi
authors.forename: Chikako
authors.initials: C
authors.lastname: Fujioka
authors.forename: Masao
authors.initials: M
authors.lastname: Kiguchi
authors.forename: Hideya
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Kihara
authors.forename: Kazuo
authors.initials: K
authors.lastname: Awai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000295:instrumentation; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D011829:Radiation Dosage; D011834:Radiation Monitoring; D011835:Radiation Protection; D011857:Radiographic Image Interpretation, Computer-Assisted; D012720:Severity of Illness Index; D061205:Vascular Calcification / Q000000981:diagnostic imaging*