Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiomediastinal contours are normal . Left lower lobe opacities likely atelectasis have improved , otherwise The lungs are clear . There is no pneumothorax or pleural effusion . There are moderate degenerative changes in the thoracic spine . The right healed rib fractures are again noted
    OUTPUT:
    
No evidence of pulmonary edema or pneumonia