Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is mild to moderately enlarged . Aorta is diffusely calcified and mildly unfolded . The mediastinal and hilar contours are unremarkable . Pulmonary vasculature is not engorged . The lungs are hyperinflated . Streaky opacities in the left lung base likely reflect areas of atelectasis . No pleural effusion , focal consolidation or pneumothorax is present . Hypertrophic degenerative changes are seen within the thoracic spine .
    OUTPUT:
    
Left basilar atelectasis .