Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . Lungs are clear . Emphysema was more easily seen on previous exam . No focal consolidation , pleural effusion , or pneumothorax is seen .
    OUTPUT:
    
No evidence of intrathoracic malignancy , infection or heart failure . Emphysema was more easily seen on previous exam .