The Research on the Volume of Artificial Structure by the Change of Scan Parameter in CT Inspection

Background/Objectives: The globular and rectangular artificial structures were prepared in order to compare the actually measured volume with the CT image volume obtained by using modified scan parameters, and to compare the errors of these volumes. Methods/Statistical Analysis: A plastic with 57.3 Mℓ globular artificial structures and a rectangular artificial structure filled with a 1.9 ℓ contrast medium mixed with distilled water at a ratio of 1:20 were placed on a table. The image data of the following conditions were obtained, namely, 5 mm, 3.75 mm, 2.5 mm, 1.25 mm, and 0.625 mm slice thicknesses; 100 kv and 120 kv tube voltages; 100 mA and 200 mA tube currents; 0% and 50% overlapped slice spaces; standard algorithm; and bone scan parameters. Findings: The volume changes in the rectangular artificial structure were less than those in the globular artificial structure. Other than the slice thickness, the effects of slice space, tube voltage, tube current, bone algorithm or standard algorithm on the image quality, and the volumes of the actual model and obtained image were insignificant. The thinner slice of the scan parameter enhanced the volume accuracy of the obtained image, while the thicker slice reduced the image distortion and accuracy. Application/Improvements: CT image accuracy and optimization are significantly dependent on the slice space. Therefore, a thin slice is absolutely required to obtain accurate CT images that are used for facial and cranial measurement in forensic medicine and dentistry, tests for restoration, liver transplant, and artificial joint tests.