Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes are present . The heart is mildly enlarged . Superior mediastinum is widened , though this partially may be due to supine positioning and low inspiratory volumes . Crowding of the bronchovascular structures is noted , but no pulmonary edema is seen . Hazy rounded opacity is seen within the left mid lung field , which is nonspecific but could reflect an area of contusion . No focal consolidation , pleural effusion or pneumothorax is present . No displaced fractures are visualized .
    OUTPUT:
    
1 . Widening of the superior mediastinum may be due to low lung volumes and supine positioning . However , if there is continued clinical concern for mediastinal injury , then a dedicated chest CTA is suggested . 2 . Nonspecific ill - defined opacity within the left mid lung field . This could reflect an area of contusion . 3 . No displaced rib fractures are identified .