Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is interval placement of a pigtail pleural catheter in the mid left chest . The large left pleural effusion however has minimally changed . The right lung is clear . The is no right pleural effusion . The cardiac silhouette is partially obscured and difficult to evaluate . The visualized mediastinal contours are otherwise stable .
    OUTPUT:
    
Interval placement of a left pleural catheter with minimal improvement in large left pleural effusion .