Yonsei Med J.  2009 Jun;50(3):385-390. 10.3349/ymj.2009.50.3.385.

Development of New Cardiac Deformity Indexes for Pectus Excavatum on Computed Tomography: Feasibility for Pre- and Post-Operative Evaluation

• Kim M
• Lee KY
• Park HJ
• Kim HY
• Kang EY
• Oh YW
• Seo BK
• Je BK
• Choi EJ

• KMID: 1758567
• DOI: http://doi.org/10.3349/ymj.2009.50.3.385

Abstract

PURPOSE: The aim of this study was to evaluate new cardiac deformity indexes (CDIs) for diagnosis of pectus excavatum as well as morphological assessment of heart on computed tomography (CT).
MATERIALS AND METHODS
We retrospectively evaluated the CT images of the control group (n=200), and the pectus excavatum before and after correction groups (n=178), and calculated the CDIs; cardiac compression index (CCI), and cardiac asymmetry index (CAI). We also calculated chest wall compression index (CWCI) and asymmetry index (CWAI) on the axial images. We performed logistic regression analysis using each index and age as predictor variables.
RESULTS
The CDIs (CCI and CAI) were significant (p < 0.05) in the diagnosis of pectus excavatum, regardless of age (p = 0.4033, p = 0.8113). The CWCI and CWAI were significant (p < 0.05) and significantly affected by age (p < 0.05). If we selected 1.82 as the cutoff of the CCI, the sensitivity and specificity were 99.4% and 98%, respectively. The following cutoffs and the sensitivity and specificity were obtained: 1.15 for the CAI gave 94.4% and 94.5%, 3.05 for the CWCI gave 92.1% and 92%, and 1 for the CWAI gave 62.4% and 65%, respectively. The CCI after repair improved from 2.83 +/- 0.84 to 1.84 +/- 0.33, while the CWCI improved from 4.49 +/- 1.61 to 2.57 +/- 0.44.
CONCLUSION
CDIs such as the CCI and CAI may be potentially useful to detect and estimate repair for pectus excavatum.

Keyword

Pectus excavatum; minimally invasive repair of pectus excavatum (MIRPE); CT scan; cardiac deformity index

MeSH Terms

Adolescent
Age Factors
Child
Child, Preschool
Female
Funnel Chest/*radiography
Heart Defects, Congenital/*radiography
Humans
Logistic Models
Male
Postoperative Period
Retrospective Studies
Tomography, X-Ray Computed/*methods
Young Adult

Figure

• 

  Fig. 1 Pre-enhanced transverse CT images in a 20-year-old man with pectus excavatum. (A) CT image obtained at the upper xiphoid process shows 4 variables for the thoracic index before correction. The line T (transverse diameter of the chest wall) indicates the widest inner transverse diameter of the thoracic cage. The line D (AP diameter of the chest wall) indicates the narrowest inner diameter from the xiphoid process to the anterior surface of the vertebral body. The lines R and L indicate the widest AP diameter in both, respectively. (B) CT image obtained at one upper level of (A) shows the 3 variables for the CDIs before correction. The line H (transverse diameter of heart) indicates the widest transverse diameter of the heart. The line M (AP diameter of the heart) indicates the narrowest diameter of the heart at the xiphoid process. The line P (paramedian diameter of the heart) indicates the widest paramedian AP diameter of the heart. (C) The CT image obtained at one upper level of the upper xiphoid process shows 3 variables for the CDIs after correction.

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  Fig. 2 Receiver operating characteristic (ROC) curves show the ability of cardiac compression (CCI), cardiac asymmetry (CAI), chest wall compression (CWCI), and chest wall asymmetry (CWAI) to reveal pectus excavatum as defined (A) without and with (B) age applied as a variable. AUC, area under the curve.

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