Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is top normal in size and appears minimally increased in size from the prior study , which may in part be due to differences in inspiration . The mediastinal contours are mildly widened when compared to prior study . Lung volumes are slightly lower than on the prior study . The pulmonary vasculature is normal . Lungs are clear . No pleural effusion or pneumothorax is seen .
    OUTPUT:
    
Slightly low lung volumes . Clear lungs . Cardiac size appears minimally increased from the prior examination , which may be due to decreases in inspiration however if there is clinical concern for mediastinal pathology or pericardial effusion , consider CT .