Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low with increased density at the lung bases , left greater than right , which could represent atelectasis , but infiltrate can not be excluded . Mild interstitial prominence is noted . No pleural effusion or pneumothorax is detected . Curvilinear density projecting over the left lung field does not follow an anatomic course and therefore is most likely external to the patient . Heart and mediastinal contours are within normal limits
    OUTPUT:
    
1 . Low lung volumes without lateral view , limiting evaluation of the lung bases . Increased density at bilateral lung bases may represent atelectasis , but is worse on the left and focal consolidation can not be excluded . 2 . Mild interstitial prominence , which could be secondary to small airways disease , viral infection , or mild edema .