Is chest radiography a valid alternative to computed tomography in evaluation of pectus excavatum?

Current pectus excavatum management includes a computed tomography scan to evaluate the correction index, whose superiority to the Haller Index in terms of specificity and sensibility is still under debate. Furthermore, several studies report interchangeability between the Haller Index as measured by computed tomography and as measured by X-radiograph; however, it is not clear whether this correlation also exists for the correction index. The aim of our study was to evaluate the correlation between measurements of the Haller Index and the correction index obtained by Computed Tomography and by X-radiograph.

This prospective study included 31 patients with pectus excavatum (who underwent preoperative chest computed tomography and X-radiograph) and a control group of 31 patients (who presented no chest deformity and underwent the same exams for other unrelated causes). We measured Haller Index and correction index on both exams for both groups. To demonstrate any correlation between computed tomography scans and X-radiographs for the two indexes, the Pearson R correlation test, Bland-Altman analysis, and ANOVA nested test were performed.

Pearson's coefficient (0.829 with P<0.0001) and ANOVA nested test showed a significant correlation and similar results between the Haller Index and the correction index on computed tomography and on X-radiograph.

Significant correlation and similar results are shown in our study in the measurement of CI and HI on computed tomography and X-radiograph. Further studies including a larger number of patients may be warranted.