320 



THE VASCULAR SYSTEM 



aneurisms of this part of the aorta and its compression is 

 followed, in the first instance, by an abductor paralysis of 

 the left vocal fold (true vocal cord, p. 338), which produces 



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FIG. 113. Transverse Section through the Thorax at the level of 

 the fourth thoracic vertebra. 



1. Left vagus nerve. 



2. Cardiac branch of sympathetic. 



3. Cardiac branch of vagus. 



4. Left phrenic nerve. 



5. Descending aorta. 



6. Aortic arch. 



7. Ascending aorta. 



8. Superior vena cava. 



9. Right phrenic nerve. 



10. Trachea. 



11. Right vagus nerve. 



12. Right bronchus. 



13. Ridge indicating bifurcation of 



trachea. 



14. Left recurrent (laryngeal) nerve. 



1 5. Vena azygos. 



16. (Esophagus. 



17. Thoracic duct. 



strident breathing and a loud "brassy" note on coughing. 

 At a later stage the fold may be completely paralysed. This 

 condition is characterised by the toneless character of the voice 

 (vox anserind) and by inability to cough in an efficient manner. 



