심혈관 CT 검사 시 적응식 통계적 반복 재구성법(ASIR)에 대한 유용성

The Usefulness of the Adaptive Statistical Iterative Reconstruction in the Cardiovascular Computed Tomography

Purpose The goals of this study was to evaluate effect of reduced radiation dose, change of CT noise, and proper amount of ASIR under assessing image quality with different ASIR amounts during cardiovascular CT examinations. Materials and methods 15 patients who had undergone routine cardiac CT for evaluation of bean problem were enrolled and all examinations were performed on a 64-MDCT scanner (Light-Speed VCT XTe, GE Healthcare, Milwaukee, USA). The GE performance evaluation phantom was scanned triple and noise were measured at center(directions of 6 o’clock) and periphery (directions of 9, 12, 3 o’clock) of phantom image under fixed 100 kVp and during changing of ASIR 0~100%. The two radiologists estimated me subjective image qualities of right coronary artery(RCA), left circumflex artery(LCX), left anterior descending artery(LAD) in reconstructed four chamber images. To assess radiation dose, CTDIvols recorded from applied ASIR man non-applied ASIR were compared and analyzed. Results In applied ASIR to image in 10 % increments (0~100%), CT noise of center(directions of 6 o’clock) and periphery(directions of 9, 12, 3 o’clock) of phantom decreased in 9.7%~49.5%, 9.8%~52.1%, 9.6%~48.9%, 9.7%~51.1%. Observer A and B estimated image quality respectively as follows: 15 and 15 patients until 60% ASIR, 13 and 13 patients until 70% ASIR, 12 and 8 patients until 80% ASIR, 8 and 6 patients until 90% ASIR, 7 and 6 patients at 100% ASIR In assessing radiation dose, CIDIvol recorded from 60% ASIR decreased in 46.9% (21.11 mGy) than non-applied ASIR(39.73 mGy) Conclusion 60% ASIR helps reduce radiation dose and acquire consistent image quality without spoiling quality.