Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is normal . The aortic knob is mildly calcified . Mediastinal and hilar contours are unremarkable . The pulmonary vascularity is normal . Minimal atelectasis is noted in the left lung base . No focal consolidation , pleural effusion or pneumothorax is present . There are no acute osseous abnormalities .
    OUTPUT:
    
Mild left basilar atelectasis .