Three-dimensional image analysis of the skull using variable CT scanning protocols-effect of slice thickness on measurement in the three-dimensional CT images.
- Author:
Ho Gul JEONG
1
;
Kee Deog KIM
;
Hyok PARK
;
Dong Ook KIM
;
Haijo JEONG
;
Hee Joung KIM
;
Sun Kook YOO
;
Yong Oock KIM
;
Chang Seo PARK
Author Information
1. Department of Oral & Maxillofacial Radiology, Oral Science Research Center, College of Dentistry, Yonsei University, Korea. kdkim@yumc.yonsei.ac.kr
- Publication Type:Original Article
- Keywords:
Imaging, Three-Dimensional;
Tomography, X-Ray Computed;
Image Analysis;
Cephalometry
- MeSH:
Cephalometry;
Humans;
Imaging, Three-Dimensional*;
Seoul;
Skull*;
Tomography, Spiral Computed;
Tomography, X-Ray Computed*
- From:Korean Journal of Oral and Maxillofacial Radiology
2004;34(3):151-157
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: To evaluate the quantitative accuracy of three-dimensional (3D) images by means of comparing distance measurements on the 3D images with direct measurements of dry human skull according to slice thickness and scanning modes. MATERIALS AND METHODS: An observer directly measured the distance of 21 line items between 12 orthodontic landmarks on the skull surface using a digital vernier caliper and each was repeated five times. The dry human skull was scanned with a Helical CT with various slice thickness (3, 5, 7 mm) and acquisition modes (Conventional and Helical). The same observer measured corresponding distance of the same items on reconstructed 3D images with the internal program of V-works 4.0 TM (Cybermed Inc., Seoul, Korea). The quantitative accuracy of distance measurements were statistically evaluated with Wilcoxons' two-sample test. RESULTS: 11 line items in Conventional 3 mm, 8 in Helical 3 mm, 11 in Conventional 5 mm, 10 in Helical 5 mm, 5 in Conventional 7 mm and 9 in Helical 7 mm showed no statistically significant difference. Average difference between direct measurements and measurements on 3D CT images was within 2 mm in 19 line items of Conventional 3 mm, 20 of Helical 3 mm, 15 of Conventional 5 mm, 18 of Helical 5 mm, 11 of Conventional 7 mm and 16 of Helical 7 mm. CONCLUSION: Considering image quality and patient's exposure time, scanning protocol of Helical 5 mm is recommended for 3D image analysis of the skull in CT.
