Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is increased left basilar opacity laterally with mild blunting of the left costophrenic angle . The lungs are otherwise clear . Cardiac and mediastinal silhouettes are stable with heavy atherosclerotic calfications of the aortic arch . No acute fractures are identified .
    OUTPUT:
    
Left basilar opacity which may be seen with atelectasis . Overyling infection or aspiration must be excluded in the proper clinical setting .