ACR White Paper-Based Comprehensive Dose Reduction Initiative Is Associated With a Reversal of the Upward Trend in Radiation Dose for Chest CT.
OBJECTIVE
In 2010, the authors' department implemented a comprehensive dose reduction strategy based on the ACR white paper on radiation dose in medicine. The aim of this study was to evaluate the effectiveness of the dose reduction program.


METHODS
In total, 1,234 adult chest CT scans from 2007 to 2012 were analyzed retrospectively, with institutional review board approval and a waiver of the requirement for informed consent. The primary outcome was effective dose in millisieverts during the three-year periods before (2007-2009) and after (2010-2012) dose reduction implementation. Dose trends were analyzed by fitted linear modeling. The use and effects on total exposure of dose reduction strategies (high pitch, adaptive statistical iterative reconstruction [ASIR], and low tube voltage) were analyzed.


RESULTS
The overall mean dose for chest CT was 7.3 ± 5.1 mSv. The mean dose decreased by 30%, from 9.2 mSv (2007-2009) to 6.5 mSv (2010-2012) (P < .001). From 2007 to 2009, the mean dose increased by 1.2 mSv per year (P < .01). From 2010 to 2012, the mean dose decreased by 1.1 mSv per year (P < 0.01). High-pitch technique, ASIR, and low tube voltage increased significantly after dose reduction implementation. High pitch and ASIR were significantly associated with a reduced dose, whereas the effect of reduced voltage was not significant.


CONCLUSIONS
Reductions in radiation exposure from medical imaging rely on ongoing technical developments and consistent, vigilant use of dose reduction strategies. This comprehensive dose reduction strategy significantly reduced radiation exposure from chest CT. Annual increases in radiation dose reversed after the strategy was implemented and continued to decline over the study period.
Department of Radiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx New York.
Udit
U
Rawat
Department of Radiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx New York. Electronic address: stuart.cohen@gmail.com.
Stuart L
SL
Cohen
Department of Radiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx New York.
Jeffrey M
JM
Levsky
Department of Radiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx New York.
Linda B
LB
Haramati
D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic / Q000592:standards; D058996:Quality Improvement; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods*; D011835:Radiation Protection; D013902:Radiography, Thoracic / Q000009:adverse effects / Q000379:methods*; D012189:Retrospective Studies; D018570:Risk Assessment; D012737:Sex Factors; D012955:Societies, Medical / Q000592:standards; D014057:Tomography, X-Ray Computed / Q000009:adverse effects / Q000379:methods*
Dose reduction; chest CT; radiation dose