Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A density projecting over the cervical spine and the lower neck is compatible with recent anterior cervical spine fusion hardware . The inspiratory lung volumes are decreased . There is retrocardiac opacification of the left lung base predominantly which may reflect atelectasis or consolidation . No significant pleural effusion or pneumothorax is detected . The pulmonary vasculature is not engorged . The cardiomediastinal silhouette is accentuated due to low lung volumes but is likely related in part to technique .
    OUTPUT:
    
Retrocardiac opacification in the setting of low lung volumes postoperatively most likely reflects bibasilar atelectasis on the left greater than right .