Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is re- demonstration of pneumomediastinum with air tracking into the subcutaneous tissues in the neck . The lungs are clear . The cardiomediastinal silhouette and hilar contours are normal . There is no pleural effusion or pneumothorax . No pneumoperitoneum is identified . Osseous structures are grossly intact .
    OUTPUT:
    
Re-demonstration of pneumomediastinum extending into the subcutaneous tissues in the neck . Overall the extent appears unchanged compared to prior CT given differences in imaging modality .