Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Mediastinal and hilar contours are unremarkable . Pulmonary vasculature is not engorged . Patchy and linear opacities within the lower lobes bilaterally likely reflect areas of atelectasis , but early infection is not completely excluded . No focal consolidation , pleural effusion or pneumothorax is identified . Mild degenerative spurring is noted in the thoracic spine .
    OUTPUT:
    
Bilateral lower lobe patchy opacities , likely atelectasis , but pneumonia is not excluded in the correct clinical setting .