Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are somewhat low . There is streaky density bilaterally most consistent with subsegmental atelectasis or scarring as before . There is evidence of a small right pleural effusion as well . The patient is status post median sternotomy and valvular plasty . A PICC remains in place . It can be followed to the upper superior vena cava . This is slightly higher than the apparent position on the prior study . There is no significant change .
    OUTPUT:
    
No significant change .