COLOR DOPPLER ULTRASONOGRAPHY FOR EVALUATION OF INTERNAL MAMMARY ARTERY THE POSSIBLE ROLE OF ARTERIAL SUPPLY TO THE COSTOSTERNAL JUNCTION IN THE ETIOLOGY OF RIGHT-CONVEX IDIOPATHIC SCOLIOSIS IN FEMALE ADOLESCENTS

Abstract

Previous investigations have postulated that the asymmetry of the breasts in female adolescents may be linked with the development of right convex thoracic scoliosis, although there is no correlation between breast asymmetry and curve type or scoliosis magnitude. This breast asymmetry is supposed to be linked with anatomic and functional asymmetry of the internal mammary artery that is the main supplier to the mammary gland. However, no measurements of anatomic and haemodynamic parameters of internal mammary artery have been made to justify or to reject the hypothesis of asymmetric blood flow volume to the breasts and costosternal junction in female adolescent scoliotics.

Twenty female adolescents with right thoracic scoliosis and 16 comparable female individuals without spine deformity were included in this study. Standing roentgenograms of the whole spine were made in all scoliotics to measure scoliosis curve, vertebral rotation and concave and convex rib-vertebra-angle at three vertebrae (apical, one level above and one below the apical vertebra). The Color Doppler Ultrasonography was used to measure at the origin of internal mammary artery its lumen diameter, cross sectional area, time average mean flow and flow volume per minute in scoliotics and controls and were compared each other. The roentgenographic parameters were compared with the ultrasonographic parameters in the scoliotics to disclose any relationship.

The reliability of color Doppler ultrasonography was high and the intraobserver variability low (ANOVA, P=0.92–0.94). There was no statistically significant difference in the ultrasonographic parameters of the internal mammary artery between right and left side in each individual as well as between scoliotics and controls. In scoliotics the right mammary artery time average mean velocity increases with the convex and concave rib-vertebra-angle one level above the apical vertebrae (P< 0.01), convex rib-vertebra angle one level below the apical vertebra (P< 0.05), and concave apical rib-vertebra angle (P< 0.01). The left internal mammary artery time average increases with only the convex rib-vertebra angle one level above the apical vertebra (P< 0.05). The right and left internal mammary artery flow volume increases with the convex rib-vertebra-angle one level above the apical vertebra (P< 0.05), while the right internal mammary artery flow volume increases furthermore with the apical concave rib-vertebra-angle (P< 0.01) and concave rib-vertebra angle one level above the apical vertebra (P< 0.01). The concave apical rib-vertebra-angle (P< 0.01) and concave rib-vertebra-angle one level above the apical vertebra (P< 0.01) increases with left internal mammary artery cross sectional area.

We concluded that anatomic and haemodynamic flow parameters measured at the origin of internal mammary artery are significantly correlated with apical rib-vertebra-angle in female adolescents suffering from right convex idiopathic thoracic scoliosis. This study did not find any evidence for side-difference in vascularity of the anterior thorax wall thus could not justify previous theories for development of right thoracic scoliosis in female adolescents.