Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: As compared to prior chest radiograph from ___ , there has been mild interval improvement of a right pneumothorax . Distance from the apical visceral pleural line to the bas of the first rib is 1 .2 cm , previously 1 .8 cm . A right basilar chest tube remains in adequate position . There is no leftward shift of the mediastinum . Cardiomediastinal and hilar contours are within normal limits . There is no pleural effusion . The left lung is clear . Subcutaneous emphysema in the right lateral chest wall is incompletely visualized .
    OUTPUT:
    
Mild interval decrease in size of the right - sided pneumothorax .