Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiomediastinal silhouette and pulmonary vasculature are unremarkable . The lungs are grossly clear aside from vague opacity in the right infrahilar region . This is not significantly changed since the prior examination . There is no pleural effusion or pneumothorax . Minimal interstitial abnormality is seen , which is most commonly present in smokers .
    OUTPUT:
    
No acute intrathoracic abnormality .