Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A right - sided chest tube has been placed . There is persistent moderate - to - large right - sided pneumothorax , but substantially decreased . Of note , however , the contours of the right upper lobe are poorly defined with an area of substantial concavity . This may indicate a substantial defect in the visceral pleura , bullous changes , atelectasis or some combination of these . Persistent short - term radiographic followup is recommended . The left lung remains clear . The cardiac , mediastinal and hilar contours appear unchanged . There is no mediastinal shift .
    OUTPUT:
    
Some decrease in large pneumothorax following right - sided chest tube placement . Irregularity and concavity of the contour of the right upper lobe suggesting a possible source for air leakage and possibly an ongoing defect ; short - term follow - up reassessment is recommended .