Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were obtained . There are low lung volumes . Previously seen left rib deformity is unchanged since the prior study . Fiducial marker is seen in the left lung . Moderate cardiomegaly is unchanged since the prior study . Bibasilar atelectasis is noted with a possible small left pleural effusion . There is no pneumothorax .
    OUTPUT:
    
Bibasilar atelectasis with possible small left pleural effusion . Otherwise , not significantly changed since the prior study .