Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Stable cardiomegaly and tortuosity of the thoracic aorta . Minimal linear atelectasis at the left lung base , but no focal areas of consolidation to suggest the presence of pneumonia . Relative flattening of hemidiaphragms suggests the possibility of COPD in the appropriate clinical setting . Bones are diffusely demineralized , and degenerative changes are present within the spine .
    OUTPUT:
    
Linear left basilar atelectasis . No evidence of pneumonia .