Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with the prior study , the previously seen right lung base pigtail catheter is no longer visualized . A moderate to moderately large right pneumothorax is newly visible . Possible small amount of fluid in the right costophrenic sulcus , unchanged . Prominence of the right hilum is again noted . The cardiomediastinal silhouette remains grossly midline . Prominence of the superior mediastinum is also again noted . On the left , there is minimal upper zone redistribution , without overt CHF . No focal infiltrate or effusion is identified in the left chest .
    OUTPUT:
    
Previously seen right pigtail catheter no longer visualized . New moderately large right pneumothorax identified . Probable small right effusion . Prominence of superior mediastinum and right hilum is similar to prior . ( Note is made that the patient underwent a chest CT on ___ ) . Aside from minimal upper zone redistribution , left lung and pleural sulcus are grossly clear . No overt CHF .