Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac , mediastinal and hilar contours are normal . Linear opacity within the left upper lobe likely reflects an area of scarring . No focal consolidation , pleural effusion or pneumothorax is present . Pulmonary vasculature is normal . There are mild degenerative changes of the thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary abnormality .