Reference value range of the ratio of ascending aortic diameter to mid-sagittal diameter of thoracic vertebrae in healthy people based on low-dose chest CT

ZHANG Chunsheng; MA Chunmei; GUAN Chunshuang; WU Jianmin; XIAO Hainan; SUN Xiaoli

doi:10.20258/j.cnki.1006-9011.2025.10.017

Abstract：Objective To measure the ratio of the ascending aorta diameter to the mid-sagittal diameter of thoracic vertebrae(A/T)in healthy people using low-dose chest CT,and to establish reference ranges for A/T in different genders and age groups.Methods A total of 2 991 healthy subjects were selected,including 1 491 males and 1 500 females.They were divided into three age groups:young(20-44 years,1 040 cases),middle-aged(45-59 years,797 cases),and elderly(60-79 years,1 154 cases).All subjects underwent low-dose chest CT scans.The ascending aorta diameter and the mid-sagittal diameter of thoracic vertebrae were measured manually at the level of the main pulmonary artery trunk,and the ratio(A/T)was calculated.Compari-sons were made between different genders and age groups regarding height,body weight,BMI,ascending aorta diameter,mid-sagittal diameter of thoracic vertebrae,and A/T.Results The ascending aorta diameter ranged from 28.20 to 33.85 mm,with a mean of(31.07±3.99)mm;the mid-sagittal diameter of thoracic vertebrae ranged from 23.50 to 26.98 mm,with a mean of(25.10±2.63)mm;and the A/T ratio ranged from 0.71 to 1.57,with a mean of 1.23±0.12.For the comparison between gen-ders,in males,the A/T ratio ranged from 0.78 to 1.57,with a mean of 1.22±0.12;in females,it ranged from 0.71 to 1.61,with a mean of 1.24±0.12.Males had significantly higher values in height,body weight,BMI,ascending aorta diameter,and mid-sagittal diameter of thoracic vertebrae than females,but a lower A/T ratio(P<0.01).As for the comparison between age groups,the A/T ranges for young,middle-aged,and elderly groups were 0.76-1.45,0.71-1.54,and 0.93-1.61,respectively,with means of 1.15±0.12,1.25±0.11,and 1.28±0.10.Significant differences were found in height,body weight,BMI,ascending aorta diameter,mid-sagittal diameter of thoracic vertebrae,and A/T among different age groups(P<0.01).In both male and female subjects,significant differences were observed in height,body weight,BMI,ascending aorta diameter,mid-sagittal diameter of thoracic vertebrae,and A/T across different age groups(P<0.05 or<0.01).Conclusion Low-dose chest CT can clearly display and measure the ascending aorta diameter and the mid-sagittal diameter of thoracic vertebrae in the same plane,and provide a reference range for A/T in the normal population.This can serve as a radiological basis for the early clinical diagnosis of diseases that cause changes in the ascending aorta diameter.