From: A novel finding related to bulla and bleb formation in patients with primary spontaneous pneumothorax
PDI sign
Total
≤ 34 years of age, nonsmokers
≤ 34 years of age, smokers
≥ 55 years of age
Control group
Number
138
64
21
26
27
Inflation time, mean, seconds
± SD
30.8 ± 48.7
42.3 ± 47.8
55.6 ± 62.5
1.9 ± 6.7
12.2 ± 43.3