Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is at the upper limits of normal size . The aorta shows mild unfolding and calcification along the arch . The lung volumes are low . Streaky left basilar opacity suggests minor atelectasis . There is no pleural effusion or pneumothorax . Mild degenerative changes are similar along the thoracic spine .
    OUTPUT:
    
Streaky left basilar opacity , unchanged , probably atelectasis , without clear evidence for pneumonia .