Evolution of coronary computed tomography radiation dose reduction at a tertiary referral center.
OBJECTIVE
We aimed to assess the temporal change in radiation doses from coronary computed tomography angiography (CCTA) during a 6-year period. High CCTA radiation doses have been reduced by multiple technologies that, if used appropriately, can decrease exposures significantly.


METHODS
A total of 1277 examinations performed from 2005 to 2010 were included. Univariate and multivariable regression analysis of patient- and scan-related variables was performed with estimated radiation dose as the main outcome measure.


RESULTS
Median doses decreased by 74.8% (P<.001), from 13.1 millisieverts (mSv) (interquartile range 9.3-14.7) in period 1 to 3.3 mSv (1.8-6.7) in period 4. Factors associated with greatest dose reductions (P<.001) were all most frequently applied in period 4: axial-sequential acquisition (univariate: -8.0 mSv [-9.7 to -7.9]), high-pitch helical acquisition (univariate: -8.8 mSv [-9.3 to -7.9]), reduced tube voltage (100 vs 120 kV) (univariate: -6.4 mSv [-7.4 to -5.4]), and use of automatic exposure control (univariate: -5.3 mSv [-6.2 to -4.4]).


CONCLUSIONS
CCTA radiation doses were reduced 74.8% through increasing use of dose-saving measures and evolving scanner technology.
Cardiac MR PET CT Program, Department of Radiology and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA. bghoshhajra@partners.org
Brian Burns
BB
Ghoshhajra
Leif-Christopher
LC
Engel
Gyöngyi Petra
GP
Major
Alexander
A
Goehler
Tust
T
Techasith
Daniel
D
Verdini
Synho
S
Do
Bob
B
Liu
Xinhua
X
Li
Michiel
M
Sala
Mi Sung
MS
Kim
Ron
R
Blankstein
Priyanka
P
Prakash
Manavjot S
MS
Sidhu
Erin
E
Corsini
Dahlia
D
Banerji
David
D
Wu
Suhny
S
Abbara
Quynh
Q
Truong
Thomas J
TJ
Brady
Udo
U
Hoffmann
Manudeep
M
Kalra
D000328:Adult; D000367:Age Factors; D000368:Aged; D000465:Algorithms; D015992:Body Mass Index; D055424:Cardiac-Gated Imaging Techniques / Q000295:instrumentation / Q000639:trends; D017023:Coronary Angiography / Q000295:instrumentation / Q000639:trends*; D004307:Dose-Response Relationship, Radiation; D006339:Heart Rate; D006801:Humans; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000295:instrumentation / Q000639:trends*; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000517:prevention & control; D011835:Radiation Protection / Q000295:instrumentation; D014481:United States