Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: When compared to prior , there has been interval development of a right basilar opacity . Retrocardiac opacity is somewhat improved although there is a probable small residual left pleural effusion . Superiorly the lungs are clear . The cardiac silhouette is enlarged but stable . Mitral valve replacements and left chest wall pacing device are unchanged .
    OUTPUT:
    
Right basilar opacity potentially atelectasis noting that infection is not excluded . Otherwise no significant interval change of probable residual left pleural effusion .