Abstract
Objectives
CT-derived assessment of regional ventilation is possible with paired inspiration and expiration scans. Normative reference values for CT-derived ventilation remain undefined. The aim of this study is to establish reference values for pulmonary ventilation using CT, with pulmonary function tests (PFTs) as the clinical standard.
Materials and methods
In this prospective, single-center study (December 2022-April 2024), 103 healthy adults underwent spirometry-guided inspiratory and expiratory CT. Lobes were segmented automatically using TotalSegmentator. Voxel-wise ventilation was quantified as the relative air volume change between inspiration and expiration via nonlinear registration, normalized to inspiratory lung volume. CT-derived lung volumes were compared with PFT-derived total lung capacity (TLC), residual volume (RV), and vital capacity (VC). Reference intervals were reported as mean +- standard deviation and 5th-95th percentiles. Multivariable analyses assessed the effects of sex, age, height, lung region, and gravitational orientation.
Results
Ninety-one participants (mean age, 53 +- 12 years; 49 men) were included. Mean ventilation was 59.5% +- 8.5% (5th-95th percentile, 42.1-72.5%). CT-derived volumes were systematically lower than PFT values but strongly correlated: CT-TLC (-13.8%