CT quantitative analysis on the pulmonary function of healthy volunteers at middle and high altitudes / 医学研究生学报

ABSTRACT

Objective The aim of this study was to investigate the pulmonary function of healthy humans at middle and high altitudes using a 256-slice multidetector CT (MDCT) scanner.Methods We enrolled 40 healthy male volunteers aged 18－45 years in this study, 20 from the middle-altitude area (at a mean altitude of 2 260 m, the MA group) and the other 20 from the high-altitude area (at a mean altitude of 4 000 m, the HA group). Using 256-slice MDCT, we performed inspiratory and expiratory CT scanning of the lungs, analyzed the images with the GE (AW 4.6) Workstation software and collected such pulmonary function parameters as the mean lung density in the full inspiratory phase (MLDin) and expiratory phase (MLDex), lung volume in the full inspiratory phase (Vin) and expiratory phase (Vex), difference between Vin and Vex (Vin-Vex), and ratio of Vin to Vex (Vin/Vex), followed by comparison of the parameters between the two groups of subjects.Results Statistically significant differences were observed between the MA and HA groups in MLDex (\[-705.90±25.63] vs \[-745.50±12.76\] HU, P=0.000) but not in MLDin (\[-869.80±20.66\] vs \[-865.85±22.57\] HU, P=0.567). The Vex was markedly higher in the HA than in the MA group (\[2 279.59±520.25\] vs \[1 566.48±350.97\] mL, P<0.05) while both Vin-Vex and Vin/Vex were remarkably lower in the former than in the latter group (P<0.05).Conclusion CT quantitative technology may offer a deeper insight into human pulmonary function at a high altitude and provide some imaging evidence for the high-altitude medical explanation of the mechanisms underlying the adaptive capacity of human pulmonary function to hypoxic environment.