Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographs demonstrate clear lungs bilaterally . There is no focal consolidation , pleural effusion , or pneumothorax . Slight atelectatic changes at the right base are unchanged since prior examination . There is persistent elevation of left hemidiaphragm consistent with patient 's known history of hiatal hernia . Mild cardiomegaly is stable . A tortuous atherosclerotic descending aorta is noted .
    OUTPUT:
    
No evidence of pneumonia .