Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographs demonstrate clear lungs without effusion or pneumothorax . The heart size is normal , the mediastinal contours are normal . There is widening of the mediastinum into the neck , which could be vascular in etiology , or due to goiter .
    OUTPUT:
    
No acute chest pathology .