Department of Dental Radiorogy, School of Dentistry, Health Sciences University of Hokkaido
Abstract
In order to evaluate image precision of a computed tomography (CT), acrylic and glass cubes soaked in the water were scaned and length was measured on a constructed image. The following conclusions were obtained from the above-mentioned results: 1. Length is different from that of the actual size according to software used for measurement in some cases. 2. Length of glass cubes with a high CT number tends to be measured longer than the actual one in comparison with acrylic cubes. 3. An error is apt to occur in the peripheral part due to the partial volume effect. 4. Difference in precision in the Z axis direction caused by the scan method is not observed. 5. Increase of errors towards the Z axis direction accompanying movement of the table is within the allowable range but should be considered clinically
