Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with ___ at 09 : 20 , the overall appearance is similar . The patchy focal opacity at the right lung base may be very slightly more confluent and dense , but this may also be accounted for by differences in positioning . Small left effusion and left base atelectasis is again noted . Cardiomediastinal silhouette and mild upper zone redistribution is probably unchanged . Oro gastric type tube and left subclavian PICC line again noted . No definite pneumothorax , though due to rotated positioning , a tiny pneumothorax in the right upper zone might not be apparent .
    OUTPUT:
    
Right upper zone opacity again seen , question slightly more confluent and denser . There remains possible that this is an artifact of positioning . Continued close attention to this area is recommended .