Calcification density on computed tomography depending on scanning parameters: phantom study

Purpose of research. The aim of the study is to evaluate changes in density, Agatston score, Volume and Mass scores of coronary calcium at different scanning parameters using phantom measurement.

Materials and methods. 8 1-ml insulin syringes filled with potassium hydroorthophosphate solution of different densities were used in the study. The syringes were placed at regular intervals into two phantoms: type 1 phantom – container filled with water; type 2 phantom – Chest Phantom N1 “LUNGMAN”. The phantoms were scanned with a Philips Ingenuity Elite CT 128 scanner using protocols with different voltages (80, 100, 120, 140 kV), amperage (27–45, 166, 330–400 mA), and slice thickness (0.625, 1, 2.5, 3 mm).

Results. Density and Agatston indexes were obtained at different scanning parameters (voltage, amperage, slice thickness) for different factors of calcification density in both phantoms. The results are presented as a table with mean density values, standard deviation (SD), Agatston score of coronary calcium, and scanning parameters.

Conclusion. The study demonstrates the influence of various scanning parameters on coronary artery calcium scoring results. The obtained information can be used in practice for more accurate quantification of coronary artery calcium, regardless of the scanning parameters.

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