Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . The aorta is unfolded . The cardiac silhouette is not enlarged . There is left base atelectasis . Retrocardiac opacity projecting over the spine on the lateral view is not well substantiated on the frontal view , underlying consolidation due to infection can not be entirely excluded . There is no pleural effusion or pneumothorax . No overt pulmonary edema is seen .
    OUTPUT:
    
Lower lobe opacity projecting over the lower spine on the lateral view , not well substantiated on the frontal view , may represent atelectasis vs consolidation .