The earliest chest X-ray change in cystic fibrosis is:
The earliest chest x-ray finding in CF lungs is hyperinflation, reflecting small-airways obstruction. Later, signs of luminal mucus impaction, bronchial cuffing, and finally bronchiectasis, e.g., ring shadows, are noticed. Ref: Harrisons Principles of Internal Medicine, 18th Edition, Page 2149.
Hyperinflation
Ring shadows
Marked increase in the bronchovascular markings
Prominent right descending pulmonary aery