Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is possible subtle opacity in the right midlung . The lungs are otherwise clear without focal consolidation , pleural effusion , pneumothorax . No pulmonary edema is seen . The heart size is normal . The mediastinal and hilar contours are normal . No signs of intra-abdominal free air are seen .
    OUTPUT:
    
Subtle right midlung opacity , nonspecific . No evidence of intra-abdominal free air .