Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is not enlarged . No CHF , focal consolidation , effusion , or pneumothorax is detected . Minimal patchy opacity at the right lung base most likely represents minimal atelectasis . An ovoid area of lucency is seen abutting the left side of the trachea , immediately above the aortic arch , measuring ___ .7 x ___ .6 mm . This is not fully characterized , but may represent a bulla or bleb in the medial portion of the left lung . A 5 .6 mm focal density overlying the anterior left third and posterior left fifth ribs may represent artifact due to overlying rib shadows . No free air seen beneath the diaphragm .
    OUTPUT:
    
Patchy opacity right lung base , likely representing minimal atelectasis . An early pneumonic infiltrate area of aspiration is considered less likely . Vertical ovoid lucency along the left trachea -- ___ full or bleb in the medial left lung . 5 .6 mm density overlying left lung laterally --? Artifact due to overlapping rib shadows . If clinically indicated , oblique views of the chest could help for further assessment .