Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Some areas of peripheral scarring are noted , and are unchanged since prior study . Small amount of atelectasis is present at the left lung base , however , there is no evidence of pulmonary edema , focal consolidation concerning for pneumonia , or significant pleural effusion . The heart size is stable . Aortic valve prosthesis is in place .
    OUTPUT:
    
No evidence of pulmonary edema or pneumonia .