Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were provided . Lung volumes are somewhat low , though the lungs appear clear . There are no convincing signs of pneumonia or CHF . No large effusion or pneumothorax is seen . Linear density is seen at the left lung base abutting the left heart border which could represent small focus of scarring . Bony structures are intact . No free air below the right hemidiaphragm is seen . Degenerative changes and DISH is noted in the T - spine .
    OUTPUT:
    
No evidence of pneumonia . Probable scarring at the left lung base .