Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP single view of the chest has been obtained with patient in upright position . Comparison is made with the frontal view of the next preceding chest examination obtained two hours earlier during the same day . Chest tube is now on suction . The volume of the basal right - sided pneumothorax cavity has markedly decreased indicating effective suction accomplished through the tube . On this single AP chest view , there is no evidence of remaining pleural effusion in the lateral pleural sinus . If the volume of the small pleural fluid residual as noted on the lateral view of the preceding examination has been changed can of course not be decided .
    OUTPUT:
    
Effective suction reducing size of residual basal pneumothorax .