Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is increased retrocardiac opacity ; however , this may be technical or external in nature given the configuration and its inferior extension to a level below the expected lower margin of the lung into the upper abdomen . Elsewhere , the lungs are clear . The cardiac silhouette is enlarged , but stable in configuration given differences in technique . Hypertrophic changes are noted in the spine .
    OUTPUT:
    
Retrocardiac opacity which is likely artifactual / technical . Consider PA and lateral to further characterize . Otherwise unremarkable .