Difference in Local Lung Movement During Tidal Breathing Between COPD Patients and Asthma Patients Assessed by Four-dimensional Dynamic-ventilation CT Scan

Figures & data

Figure 1 The measurement point of lung movement in our study.

Table 1 Characteristics of COPD Patients and Patients with Asthma

	COPD (n=33)	Asthma (n=11)	p-value
Age (years)	74 (44–89)	55 (32–75)	<0.01
Gender (male/female)	30/3	5/6	<0.01
BMI (kg/m^2)	21.1 (15.6–31.3)	22.6 (15.6–27.9)	0.43
Alb (g/dL)	4.1 (2.7–4.6)	4.3 (3.7–4.7)	0.09
Smoking index (pack-years)	43 (0–150)	0 (0–51)	<0.01
Smoking status (current/ex/never)	(5/27/1)	(2/2/7)	<0.01
Goddard score	6 (0–12)	6 (5–6)	0.03
GOLD (I/II/III/IV)	12/12/9/0	0/1/0/0^a
FEV1 (L)	1.43 (0.71–3.28)	2.24 (1.43–4.91)	0.03
FEV1/FVC (%)	55.9 (29.7–68.9)	73.2 (55.0–79.4)	<0.01
TV (L)	0.91 (0.31–2.27)	0.97 (0.69–1.25)	0.87
LAV% (%)	13.7 (0.4–33.9)	0.9 (0.3–19.8)	0.01

Notes: ^aEight did not have obstructive impairment. Two did not perform spirometry. Data presented as median and IQR or categorical variables were presented as numbers (n) and percentages (%).

Table 2 Displacement of COPD Patients and Patients with Asthma

	COPD (n=33)	Asthma (n=11)	p-value
Right
Apex	1.9 (0.7–4.1)	3.1 (0.6–6.0)	0.06
CPA	20.2 (6.5–37.8)	21.0 (13.5–32.5)	0.41
Top of the diaphragm	13.3 (6.9–27.1)	15.5 (11.2–29.5)	0.04
Ventral part	5.5 (1.5–13.4)	10.7 (4.6–25.2)	<0.01
Midpoint between apex and CPA	9.2 (2.2–27.3)	11.9 (3.8–15.3)	0.36
Midpoint between ventral part and apex	4.5 (1.5–9.0)	7.4 (2.5–17.1)	0.13
Left
Apex	1.89 (0.7–4.1)	3.41 (0.9–6.8)	0.23
CPA	20.2 (6.5–37.8)	19.9 (12.3–34.3)	0.54
Top of the diaphragm	13.3 (6.9–27.1)	15.4 (10.7–33.9)	0.19
Ventral part	5.5 (1.5–13.4)	13.3 (4.8–20.8)	<0.01
Midpoint between apex and CPA	9.2 (2.2–27.3)	14.8 (5.4–16.3)	0.03
Midpoint between ventral part and apex	5.18 (1.5–10.7)	7.1 (3.7–16.1)	0.07

Note: Data presented as median and IQR.

Table 3 Velocity During Inhalation of COPD Patients and Patients with Asthma

	COPD (n=33)	Asthma (n=11)	p-value
Right
Apex	6.8 (0.4–16.7)	10.7 (1.6–24.7)	0.06
CPA	64.4 (32.4–147.7)	79.9 (48.7–116.3)	0.35
Top of the diaphragm	45.8 (20.9–90.4)	55.9 (35.6–105.0)	0.03
Ventral part	21.1 (6.8–46.6)	48.7 (19.0–74.4)	<0.01
Midpoint between apex and CPA	34.5 (8.8–74.5)	35.6 (11.9–70.5)	0.61
Midpoint between ventral part and apex	17.7 (5.1–40.9)	29.2 (10.4–46.3)	0.07
Left
Apex	9.9 (3.0–18.6)	12.0 (2.5–20.5)	0.42
CPA	64.9 (31.8–143.1)	70.9 (33.0–97.5)	0.31
Top of the diaphragm	45.9 (27.8–86.0)	61.7 (34.9–101.0)	0.24
Ventral part	17.7 (8.8–55.9)	47.7 (20.2–69.2)	<0.01
Midpoint between apex and CPA	32.2 (13.2–58.9)	42.9 (15.2–56.5)	0.16
Midpoint between ventral part and apex	17.1 (5.4–45.5)	31.8 (13.0–53.0)	0.04

Note: Data presented as median and IQR.

Table 4 Velocity During Exhalation of COPD Patients and Patients with Asthma

	COPD (n=33)	Asthma (n=11)	p-value
Right
Apex	6.2 (1.8–16.2)	8.2 (2.6–21.8)	0.35
CPA	82.7 (35.3–141.0)	83.6 (44.1–123.6)	0.75
Top of the diaphragm	46.2 (22.2–91.5)	66.2 (36.2–89.7)	0.03
Ventral part	15.9 (5.6–50.9)	41.1 (11.3–80.2)	<0.01
Midpoint between apex and CPA	32.4 (6.9–67.4)	38.4 (14.5–78.8)	0.71
Midpoint between ventral part and apex	17.6 (5.2–39.3)	24.0 (7.5–60.8)	0.20
Left
Apex	7.8 (3.5–16.7)	10.2 (3.2–21.4)	0.96
CPA	78.8 (33.7–124.3)	62.4 (36.5–99.7)	0.32
Top of the diaphragm	51.1 (22.2–85.8)	49.8 (32.1–95.5)	0.81
Ventral part	17.2 (7.0–34.3)	40.0 (13.5–67.2)	<0.01
Midpoint between apex and CPA	33.8 (11.1–63.4)	41.1 (19.1–57.0)	0.18
Midpoint between ventral part and apex	15.8 (6.9–33.7)	18.5 (13.2–47.5)	0.10

Note: Data presented as median and IQR.

Table 5 Characteristics of COPD Patients with Mild Emphysema and Patients with Asthma

	COPD with Mild Emphysema (n=20)	Asthma (n=11)	p-value
Age (years)	74 (44–89)	55 (32–75)	<0.01
Gender (male/female)	17/3	5/6	0.03
BMI (kg/m^2)	22.1 (15.6–31.3)	22.6 (15.6–27.9)	0.93
Alb (g/dL)	4.2 (3.0–4.6)	4.3 (3.7–4.7)	0.24
Smoking index (pack-years)	41.8 (0–88)	0 (0–51)	<0.01
Smoking status (current/ex/never)	(5/14/1)	(2/2/7)	<0.01
Goddard score	6 (0–7)	6 (5–6)	0.91
GOLD (I/II/III/IV)	8/10/2/0	0/1/0/0^a
FEV1 (L)	1.79 (0.78–3.28)	2.24 (1.43–4.91)	0.11
FEV1/FVC (%)	61.3 (39.6–68.9)	73.2 (55.0–79.4)	<0.01
TV (L)	0.78 (0.31–2.27)	0.97 (0.69–1.25)	0.21
LAV% (%)	5.4 (0.4–18.4)	0.9 (0.3–19.8)	0.28

Notes: ^aEight did not have obstructive impairment. Two did not perform spirometry. Data presented as median and IQR or categorical variables were presented as numbers (n) and percentages (%).

Table 6 Displacement of COPD Patients with Mild Emphysema and Patients with Asthma

	COPD with Mild Emphysema (n=20)	Asthma (n=11)	p-value
Right
Apex	2.17 (0.7–2.7)	3.1 (0.6–6.0)	0.11
CPA	18.5 (10.2–32.4)	21.0 (13.5–32.5)	0.16
Top of the diaphragm	12.7 (7.4–24.4)	15.5 (11.2–29.5)	0.01
Ventral part	5.5 (1.5–13.4)	10.7 (4.6–25.2)	<0.01
Midpoint between apex and CPA	8.7 (2.2–18.8)	11.9 (3.8–15.3)	0.38
Midpoint between ventral part and apex	4.3 (1.5–9.0)	7.4 (2.5–17.1)	0.10
Left
Apex	2.56 (0.71–4.57)	3.41 (0.9–6.8)	0.24
CPA	17.4 (7.8–28.2)	19.9 (12.3–34.3)	0.38
Top of the diaphragm	12.3 (8.4–25.9)	15.4 (10.7–33.9)	0.11
Ventral part	4.9 (3.4–10.2)	13.3 (4.8–20.8)	<0.01
Midpoint between apex and CPA	9.5 (3.1–16.7)	14.8 (5.4–16.3)	0.10
Midpoint between ventral part and apex	5.2 (2.4–10.7)	7.1 (3.7–16.1)	0.10

Note: Data presented as median and IQR.

Table 7 Velocity During Inhalation of COPD Patients with Mild Emphysema and Patients with Asthma

	COPD with Mild Emphysema (n=20)	Asthma (n=11)	pvalue
Right
Apex	7.3 (0.4–13.1)	10.7 (1.6–24.7)	0.09
CPA	63.4 (32.4–112.1)	79.9 (48.7–116.3)	0.16
Top of the diaphragm	42.3 (20.9–84.4)	55.9 (35.6–105.0)	<0.01
Ventral part	20.8 (1.5–13.4)	48.7 (19.0–74.4)	<0.01
Midpoint between apex and CPA	31.5 (8.8–61.9)	35.6 (11.9–70.5)	0.48
Midpoint between ventral part and apex	16.0 (5.12–40.6)	29.2 (10.4–46.3)	0.03
Left
Apex	10.0 (3.6–16.0)	12.0 (2.5–20.5)	0.50
CPA	60.5 (31.8–85.2)	70.9 (33.0–97.5)	0.18
Top of the diaphragm	44.3 (27.8–86.0)	61.7 (34.9–101.0)	0.13
Ventral part	17.6 (8.7–55.9)	47.7 (20.2–69.2)	<0.01
Midpoint between apex and CPA	32.6 (13.2–58.9)	42.9 (15.2–56.5)	0.22
Midpoint between ventral part and apex	16.7 (8.5–39.5)	31.8 (13.0–53.0)	0.05

Note: Data presented as median and IQR.

Table 8 Velocity During Exhalation of COPD Patients with Mild Emphysema and Patients with Asthma

	COPD with Mild Emphysema (n=20)	Asthma (n=11)	p-value
Right
Apex	6.6 (1.8–14.3)	8.2 (2.6–21.8)	0.56
CPA	72.0 (35.3–141.0)	83.6 (44.1–123.6)	0.70
Top of the diaphragm	40.5 (24.3–91.5)	66.2 (36.2–89.7)	0.02
Ventral part	14.9 (5.6–50.9)	41.1 (11.3–80.2)	<0.01
Midpoint between apex and CPA	31.2 (6.9–67.4)	38.4 (14.5–78.8)	0.61
Midpoint between ventral part and apex	15.4 (5.2–38.2)	24.0 (7.5–60.8)	0.13
Left
Apex	8.6 (3.5–16.7)	10.2 (3.2–21.4)	0.86
CPA	72.4 (33.7–112.4)	62.4 (36.5–99.7)	0.76
Top of the diaphragm	50.6 (25.9–85.8)	49.8 (32.1–95.5)	0.95
Ventral part	17.8 (8.9–34.3)	40.0 (13.5–67.2)	<0.01
Midpoint between apex and CPA	36.2 (11.1–51.3)	41.1 (19.1–57.0)	0.61
Midpoint between ventral part and apex	15.4 (7.4–33.7)	18.5 (13.2–47.5)	0.08

Note: Data presented as median and IQR.

Figure 2 A series of box-plots showing displacement of the ventral point of the right lung. (A) A box-plot of COPD. (B) A box-plot of asthma. It demonstrates greater alteration for displacement in asthma patients, compared with COPD patients. Box plots of measurement of displacement and velocity value in abdominal part of the lung. “Displacement” means the amount of movement of the interest target voxel which move from the initial phase. “Velocity” means the amount of velocity of the interest target voxel which move from the previous phase. X axis is the one respiratory phase starting from the level of peak inspiratory phase. The X-axis represents one respiratory cycle, and this is a reconstruction of one breath into 28 phases bin starting from the peak inspiratory phase. The Y-axis represents “displacement” and “velocity”, and is a measurement at each respiratory phase for each patient group.

Notes: Boxes: upper to lower quartile, thin line: maximum and minimum (excluding outliers and extreme values).

Figure 3 A series of box-plots showing velocity of the ventral point of the right lung. (A) A box-plot of COPD. (B) A box-plot of asthma. It demonstrates greater alteration for velocity in asthma patients, compared with COPD patients.

Figure 4 A series of box-plots showing displacement of the ventral point of the left lung. (A) A box-plot of COPD. (B) A box-plot of asthma. It also demonstrates greater alteration for displacement in asthma patients, compared with COPD patients.

Figure 5 A series of box-plots showing velocity of the ventral point of the left lung. (A) A box-plot of COPD. (B) A box-plot of asthma. It also demonstrates greater alteration for velocity in asthma patients, compared with COPD patients.

Figure 6 Typical movement of the lung. The amount of local lung movement was quantified and displayed as “displacement map”. The local lung movement in COPD patients were significantly smaller than those in asthma patients especially in the ventral part of the lung. Color wash range: displacement: 0–10. (A) A typical movement of COPD. (B) A typical movement of asthma.