Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph provided . The chest tube projects over the right lateral hemithorax with lateralizing right pleural effusion again seen . There is right perihilar opacity which appears similar to the prior exam allowing for slight changes in patient positioning . The left lung is mostly clear , though there may be mild atelectasis at the left lung base . The heart size is unchanged . Bony structures are intact .
    OUTPUT:
    
No significant change given slight differences in technique .