1. trachea
2. esophagus
3. right common carotid artery
4. left common carotid artery
5. left vertebral artery
6. right vertebral artery
7. left vertebral vein
8. right vertebral vein
9. left internal jugular vein
10. right lobe of thyroid gland
11. left lobe of thyroid gland
12. anterior scalene
13. sternocleidomastoid
