Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low but unchanged since previous exam . The lungs are clear without focal opacities to suggest pneumonia . Mild cardiomegaly is unchanged . Mediastinal silhouette and hilar contours are normal . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
1 . Mild cardiomegaly is unchanged since previous exam . 2 . There are no new focal airspace opacities to suggest pneumonia .