Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Improved lung volumes compared with prior exam with mild residual left basal atelectasis . No pulmonary edema , pneumothorax or large effusion . The cardiomediastinal silhouette is normal . Imaged osseous structures are intact . No free air below the right hemidiaphragm is seen .
    OUTPUT:
    
Mild left basilar atelectasis .