Uji linearitas CT Number dan Resolusi Spasial Menggunakan ACR 464 Phantom Pada Kualitas Citra Pesawat CT-Scan 16 Slice”

Abstract

Research has been carried out on the CT Number linearity test and spatial resolution on CT-Scan images using the American College of Radiology (ACR) Phantom. The aim is to determine the correlation coefficient formed from the linearity of the relationship between the CT number value and electron density and to determine the spatial resolution value and to determine the effect of slice thickness on CT-scan images by varying the slice thickness (1.0 mm, 2.0 mm and 4.0 mm). The CT Number value is indicated by the placement of a circle-shaped ROI with a size of 20 mm and using a tube voltage exposure factor of 120 kV and a tube current of 300 mA. From the measurement results, the linearity correlation coefficient value of CT Number with electron density at a slice thickness of 1.0 mm is 0.9997; slice thickness of 2.0 mm is 0.9996; and the slice thickness of 4.0 is 0.9995 with a passing value of R2≥0.99. In the results of the spatial resolution measurements, the values for each slice thickness were 0.5 lp/mm; 0.6 lp/mm; and 0.7 lp/mm with a test pass value of ≥0.5 lp/mm, then these values are not less than the pass test value and are still in accordance with BAPETEN regulatory standards No. 2 of 2018 concerning the value of passing the test for conformity test parameters for CT-Scan X-ray aircraft.