Abstract
A comparison of the image quality of a high resolution scan (HR scan) and a standard scan (ST scan) of a 7020 CT scanner was made by means of physical evaluation and psychological visual evaluation. According to the physical evaluation, it has been found that the HR scan was superior in modulation transfer function, but inferior in noise and contrast scale to the CT scan. Both the HR scan and the ST scan were satisfactory in uniformity and linearity. The ST scan was superior to the HR scan according to the psychological visual evaluation. This was probably due to the increase of noise in the HR scan. It may be concluded from the results of this comparison that the HR scan is suited to differentiate the fine structures in a high contrast area, while the ST scan is suited for a scan in a low contrast area.
