Coronary XXXX quantification using various calibration phantoms and scoring thresholds.

@entity1 @entity460
RATIONALE AND OBJECTIVES: To compare scoring threshold and calibration method-dependent accuracy and variability of coronary @entity460 measurements by multidetector computed tomography (MDCT). METHODS: Ninety-five subjects were scanned with MDCT. We calculated Agatston score and volume score. Mineral mass (MM) was calculated using @entity1 -based and scanner-based calibration methods. Accuracy of calibration was validated using artificial @entity460 cylinders. RESULTS: @entity1 -based and scanner-based calibration permitted accurate quantification of artificial @entity460 cylinders (bias: 0 mg and -2 mg). In the subjects, the mean relative difference of MM measurements performed at 90 and 130 Hounsfield units threshold (59%) was lower than for Agatston score (94%) and volume score (109%; P < 0.05). @entity1 -based and scanner-based calibration yielded systematically different MM measurements (bias: 22%). CONCLUSIONS: MM lowers threshold-dependent variability of coronary @entity460 measurements. @entity1 -based and scanner-based calibration allows accurate @entity460 quantification ex vivo but reveal systematic differences in subjects. @entity1 -based calibration may better account for subject size and composition.
