Normalized mean shapes and reference index values for computerized quantitative assessment indices of chest wall deformities

• Published in: Journal of the Korean Physical Society Vol. 67; no. 10; pp. 1868 - 1875
• Main Authors: Kim, Ho Chul, Park, Man Sik, Lee, Seong Keon, Nam, Ki Chang, Park, Hyung Joo, Kim, Min Gi, Song, Jae-Jun, Choi, Hyuk
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Physical Society 01.11.2015; 한국물리학회
• Subjects: Mathematical and Computational Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Theoretical; 물리학; Mean shape; Pectus excavatum; Chest wall deformity; Eccentricity index; Haller index; Reference index values
• ISSN: 0374-4884; 1976-8524
• DOI: 10.3938/jkps.67.1868

We previously proposed a computerized index (eccentricity index [EI]) for chest-wall deformity measurements, such as pectus excavatum. We sought to define mean shapes based on normal chest walls and to propose for computerized index reference values of that are used in the quantitative analysis of the severity of chest-wall deformities. A total of 584 patients were classified into 18 groups, and a database of their chest-wall computed tomography (CT) scan images was constructed. The boundaries of the chest wall were extracted by using a segmentation algorithm, and the mean shapes were subsequently developed. The reference index values were calculated from the developed mean shapes. Reference index values for the EI were compared with a conventional index, the Haller index (HI). A close association has been shown between the two indices in multiple subjects (r = 0.974, P < 0.001). The newly developed mean shapes and reference index values supply both reliability and objectivity to the diagnosis, analysis, and treatment of chest-wall deformities. They promise to be highly useful in clinical settings.