Vector-field dynamic x-ray (VF-DXR) using optical flow method in patients with chronic obstructive pulmonary disease

European Radiology Experimental

Table 1 Demographic data and PFTs among normal, COPD mild, and COPD severe groups

Variables	Normal (n = 47)	COPD mild (n = 14)	COPD severe (n = 22)	p value
Variables	Median [IQR]	Median [IQR]	Median [IQR]	p value
Age (years)	55 [49, 61]	77.5 [71.5, 79]	67.5 [63.5, 76.3]	< 0.001
Sex, females/males	27/20	2/12	3/19	< 0.001
Height (cm)	162.3 [155, 169.6]	164.5 [161.5, 167]	164.5 [158.3, 167.5]	0.907
Weight (kg)	61.2 [51.6, 66.3]	57.9 [54.6, 62.5]	50.0 [47.0, 60.8]	0.210
BMI (kg/m²)	22.7 [20.4, 23.7]	22.6 [20.5, 23.4]	19.7 [18.0, 22.5]	0.083
Smoking History	Never	Current or former	Current or former
GOLD, 1/2/3/4	Not applicable	4/10/0/0	0/0/17/5
PFT
TV (L)	0.60 [0.50, 0.98]	1.09 [0.75, 1.23]	0.84 [0.72, 0.97]	0.006
VC (L)	3.25 [2.64, 3.80]	3.11 [2.85, 3.50]	2.47 [1.94, 2.79]	< 0.001
%VC	106.1 [99.9, 117.5]	104.3 [91.5, 115.2]	79.9 [68.9, 90.4]	< 0.001
FEV₁ (L)	2.58 [2.18, 3.19]	1.72 [1.56, 1.98]	0.93 [0.82, 1.03]	< 0.001
FEV₁%	81.6 [79.0, 85.7]	58.8 [53.6, 60.7]	41.2 [36.6, 44.8]	< 0.001
%FEV₁	105.2 [98.7, 113.8]	70.2 [59.1, 79.4]	37.2 [31.2, 42.4]	< 0.001

Demographic data including age, height, weight, and BMI were assessed with one-way analysis of variance. Sex distribution was evaluated with Fisher’s exact test. Each pulmonary functional data was examined with one-way analysis of variance on ranks. BMI Body mass index, COPD Chronic obstructive pulmonary disease, FEV₁ Forced expiratory volume in one second; FEV₁% Forced expiratory volume percent in one second divided by forced vital capacity, %FEV₁ Percent predicted forced expiratory volume in one second; GOLD Global initiative for chronic obstructive lung disease; IQR Interquartile range, PFT Pulmonary function tests; TV Tidal volume, VC Vital capacity, %VC Percent predicted vital capacity