Form Reappearance of the Section Sensitivity Profile on Z-axis in Multi-detector Spiral Computed Tomography

The filter is hung in the direction of slice thickness (Z-axis) in the reconstruction of multi-detector spiral CT. Because of this, performing several time scans is considered useful from the standpoint of reappearance of the section sensitivity profile curves. However, when examination is done at full width half maximum (FWHM) and the position of the center of FWHM, there is non-symmetry and the level of hem extent of the section sensitivity profile curves. Change in FWHM and the position of the center of FWHM increases as pitch increases. Although the change in FWHM was less when the reconstruction slice thickness was increased, the change became larger in the center of FWHM as well. As for the non-symmetry of the section sensitivity profile curves and the level of hem extent, the change decreased when the reconstruction slice thickness was increased, although it increased when pitch was enlarged. It is considered that the cause of these changes is change in table movement speed during scanning.