The Relationship between Subjective and Objective Parameters in CT Phantom Image Evaluation.
10.3348/kjr.2009.10.5.490
- Author:
Hye Jung PARK
1
;
Seung Eun JUNG
;
Young Joon LEE
;
Woo Il CHO
;
Kyung Hyun DO
;
Seung Hyup KIM
;
Ki Hwang KIM
Author Information
1. Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea. sejung@catholic.ac.kr
- Publication Type:Original Article ; Comparative Study
- Keywords:
Computed tomography (CT), image quality;
Phantoms
- MeSH:
Artifacts;
Korea;
*Phantoms, Imaging;
*Tomography, X-Ray Computed
- From:Korean Journal of Radiology
2009;10(5):490-495
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: To evaluate whether there is a relationship between subjective parameters determined by a reviewer (spatial resolution, low contrast resolution, and artifacts) and objective parameters (the CT number of water, noise, and image uniformity) in CT phantom image evaluations. MATERIALS AND METHODS: We reviewed the CT results of phantom image evaluations conducted by Korean Institute for Accreditation of Medical Image (KIAMI) from May 2007 to June 2007. We compared the objective parameters against the pass or fail groups for the subjective parameters. We also evaluated whether there is a relationship between the artifact types and the other subjective parameters. RESULTS: The mean noise value was significantly higher in the fail groups for the subjective parameters compared to the pass groups (p = 0.006). Specifically, noise and low contrast resolution were found to have a statistically significant positive correlation (r = 0.183, p < 0.001). In the fail group for low contrast resolution, the failure due to artifacts was significantly higher than the pass group (p < 0.001). In contrast, no statistically significant differences were found for the mean CT number of water, noise, or image uniformity based on the types of artifacts. CONCLUSION: Subjective CT image parameters evaluated by a reviewer correlate with objectively measured parameters, especially noise. Therefore, a stricter noise standard might be able to improve the subjective parameters results, such as low contrast resolution.
