Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiomediastinal silhouette is mildly enlarged . Chronic height middle lobe and bibasilar atelectasis or scarring . No focal consolidation to suggest pneumonia . Mediastinal contour is unchanged . No overt pulmonary edema seen . There is a subtle area of cortical irregularity involving the lateral right fourth rib anteriorly , age indeterminate .
    OUTPUT:
    
1 . Chronic right middle lobe and bibasilar atelectasis or scarring . No focal consolidation . 2 . Subtle irregularity along the anterior lateral fourth rib representing fracture , age indeterminate , evaluate for pain in this region . 3 . Mild cardiomegaly , unchanged .