Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Heart size is top normal . Mild tortuosity of thoracic aorta is again noted . Mediastinal and hilar contours are otherwise unremarkable . Pulmonary vasculature is not engorged . Patchy opacities in the left lung base likely reflect areas of atelectasis , without focal consolidation . No pleural effusion or pneumothorax is present . Screw projects over the right humeral head . Mild degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
Low lung volumes with patchy left basilar opacity , likely atelectasis .