Multidetector computed tomographic assessment of the normal diameters for the thoracic aorta and pulmonary arteries in infants and children.

<bold>Background: </bold>Knowledge of the normal size of the thoracic aorta and pulmonary arteries is important regarding the detection of the abnormal and valuable in the treatment of patients with congenital and acquired cardiovascular diseases. <bold>Purpose: </bold>To determine the normal diameters of the thoracic vascular structures of pediatric participants on contrast-enhanced multidetector computer tomography (MDCT) scans. <bold>Material and Methods: </bold>Between July 2010 and July 2014, the MDCT examinations obtained from 520 participants (age range, 0-18 years; mean age, 8.49 years ± 5.54 [standard deviation]; male:female ratio, 1.6:1) with normal cardiovascular examinations were retrospectively evaluated. Patients were divided into six groups according to their age. Diameters of the ascending aorta (AA), descending aorta (DA), main pulmonary artery (MPA), right pulmonary artery (RPA), and left pulmonary artery (LPA) were measured. <bold>Results: </bold>The diameters of the thoracic vascular structures increased with age and the statistical difference among the age groups and genders were significant. The vascular structures in male patients tended to have higher dimensions than female patients. The LPA demonstrated higher mean values than the RPA in each age group. The mean ratio PA (MPA/AA) is 0.93 ± 0.08 for pediatric participants and it is slightly higher in girls compared to boys (0.93 ± 0.07 and 0.92 ± 0.07, respectively). The level of pulmonary artery bifurcation moves caudally with increasing age with thoracal 6 vertebra being the most common for all age groups (53.3%). <bold>Conclusion: </bold>We believe that the results of our study can serve as a potential reference in differentiating the normal from the abnormal size of the aorta and pulmonary arteries on chest MDCT studies in the pediatric population. [ABSTRACT FROM AUTHOR]