Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a catheter the left lung base , though it is difficult to trace beyond the chest wall due to increased opacification . However , there has been interval considerable interval decrease the size of the large left pleural effusion . The left upper zone is no aerated . A relatively large effusion remains present , with underlying collapse and / or consolidation . No pneumothorax is detected . On the right , a small right pleural effusion is again seen , but the right lung remains grossly clear . No right - sided consolidation . No CHF .
    OUTPUT:
    
1 . Interval placement of catheter the left lung base , with considerable interval decrease in size of left pleural effusion . 2 . A moderate to moderately large left pleural effusion remains present , with underlying collapse and / or consolidation .