Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Focal ill - defined opacity is seen at the right lung base which could represent atelectasis , less likely pneumonia . No effusions or pneumothorax . Cardiomediastinal silhouette stable . Bony structures intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
Minimal opacity at the right lung base most likely atelectasis , though can not exclude a tiny focus of pneumonia .