Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is mild hyperexpansion likely due to underlying obstructive lung disease . Minimal left base atelectasis is evident . No focal consolidation or superimposed edema is noted . Mediastinum is unremarkable . The cardiac silhouette is within normal limits for size . No effusion or pneumothorax is noted . Degenerative changes are seen throughout the thoracic spine and in bilateral shoulders . Clips are evident posteriorly in the medial left upper quadrant .
    OUTPUT:
    
Likely underlying obstructive lung disease . No superimposed acute process identified .