Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable view of the chest is compared to previous exam from ___ . Low lung volumes are seen on the current exam . There is retrocardiac opacity which silhouettes the hemidiaphragm . This could be accounted for by atelectasis given lower lung volumes on the current exam noting that effusion or consolidation can not be excluded . Elsewhere , the lungs are grossly clear . Cardiomediastinal silhouette is stable as are the osseous and soft tissue structures .
    OUTPUT:
    
Limited exam due to low inspiratory effort . Retrocardiac opacity may be due to atelectasis ; however , effusion or consolidation also possible . Repeat with PA and lateral could offer additional detail if patient is amenable .