Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable upright AP view of the chest provided . There is mild left basilar atelectasis . Otherwise , the lungs are clear . No pneumothorax or pleural effusion . Cardiomediastinal silhouette is normal . Bony structures are intact . No signs of pneumomediastinum or free air below the right hemidiaphragm .
    OUTPUT:
    
Mild left basal atelectasis , otherwise normal .