Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP chest radiograph . The lungs are hyperexpanded . Blunting of the bilateral costophrenic sulci may represent either small pleural effusions or pleural thickening . There is no evidence of pulmonary edema . The heart size is normal . There is no pneumothorax .
    OUTPUT:
    
No evidence of pulmonary edema .