Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Hyperexpansion of the lungs and flattening the hemidiaphragms suggest severe chronic obstructive pulmonary disease . Lungs are clear without confluent consolidation . There is no overt interstitial edema or large pleural effusion . Cardiomediastinal and hilar contours are within normal limits . There is no pneumothorax .
    OUTPUT:
    
Severe chronic obstructive pulmonary disease , though no acute cardiopulmonary process .