OBJECTIVES: To determine the value of ultra-low dose chest CT with tin filtration for ordinal coronary artery calcium (CAC) risk scoring.
METHODS: 50 patients were prospectively included and underwent clinical standard dose chest CT (1.8±0.7mSv) and ultra-low dose CT (0.13±0.01mSv). Four radiologists estimated presence and extent of CAC.
RESULTS: Weighted kappa values for CAC were 0.76-0.97 in standard dose and 0.75-0.95 in ultra-low dose CT (p<0.001). Good to excellent agreement was observed for CAC ordinal risk assessment, with readers reporting identical risk in 81% of cases.
CONCLUSION: CAC risk can be qualitatively assessed from X-ray dose equivalent ungated chest CT.