Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is mildly enlarged . The aorta is mildly tortuous . Mediastinal and hilar contours are unremarkable , and the pulmonary vascularity is normal . There is minimal patchy opacity within the left lung base . This could reflect atelectasis as the lung volumes are slightly low . No pleural effusion or pneumothorax is present . Mild degenerative changes of the thoracic spine are present .
    OUTPUT:
    
Low lung volumes with left basilar patchy opacity which could represent atelectasis . Infection is not completely excluded .