Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . Lungs are clear . There is blunting of the right costophrenic angle , which could represent pleural thickening or a residual small pleural effusion . No pneumothorax is seen .
    OUTPUT:
    
Blunting of the right costophrenic angle , representing either pleural thickening or small pleural effusion .