Pulmonary scintigraphic findings in children with pectus excavatum by the comparison of chest radiograph indices.

Pulmonary scintigraphy, including Xe-133 ventilation combined with Tc-99m MAA perfusion scans, was performed in 23 children (3 girls, 20 boys, ages: 2-9 years) with pectus excavatum, and the indices from lateral chest radiography were used for comparison. The findings of pulmonary scintigraphy were analyzed as 1) ventilation fractions (VF), and 2) perfusion fractions (PF) between bilateral lungs; and 3) ventilation-perfusion ratios (V/Q ratio) of both lungs. The results showed that 6 of 23 cases had impaired VF, 11 of 23 cases had impaired PF, and 7 of 23 cases had an impaired V/Q ratio in the right and left lung, respectively. The severity of sternal depression in pectus excavatum was shown as certain indices that were obtained on routine lateral chest radiographs. However, no significant correlations existed between the differences in the fractions and the indices. Our results suggest that pulmonary scintigraphy is not necessary for children with pectus excavatum to predict the severity of sternal depression and pulmonary function, because 1) pulmonary scintigraphy is very difficult to perform in children; 2) unnecessary radiation exposure should be avoided; and 3) it is not well correlated with the severity of the depressed sternum.