Determining the Feasibility of Dose Reduction Strategies on Radiation Dose: An Experimental Phantom Study

ABSTRACT

@#Introduction: Radiation exposure during the CT examination has always been a concern due to its associated cancer risk. The guidelines suggest the optimization of radiation dose reduction. Therefore, this study aims to determine the feasibility of dose reduction strategies on radiation dose reduction using a phantom. Methods: Head and body phantoms of 16 cm and 32 cm, respectively, were used to calculate the radiation dose and measure the quantitative image quality. The phantoms were positioned and scanned with the standard protocol and low dose protocol. For dose reduction strategies, scan length was reduced in head phantom, and tube voltage and tube current were manipulated individually and by combining both and tested in both head and body phantoms. Also, the influence of rotation time was investigated in body phantom. Quantitative image quality was determined by drawing a region of interest on the obtained image. Results: Reducing scan length showed 41% reduction of radiation dose and reducing tube current, and tube voltage showed up to 75% reduction of radiation dose in head phantom and 70% reduction of radiation dose in body phantom compared to the standard protocol. The reduction of the rotation time, however, reduced the scan time and the radiation dose but the maximum mAs or tube current allowed was limited. Quantitative image quality was reduced when using a lower dose protocol. Conclusion: The dose reduction strategies showed a reduced dose, but the quantitative image quality score was reduced when scanned with low dose protocol. Further manipulation can be performed to maintain image quality.