18 Questions
What is the function of the thymus?
Production of T-cells
Where is the thymus located?
Posterior to the manubrium of the sternum
What is the main artery in the superior mediastinum?
Brachiocephalic artery
Which nerves are found in the superior mediastinum?
Phrenic nerves and vagus nerves
What happens to the thymus after puberty?
It starts to decrease in size
Which structure is located immediately posterior to the thymus?
Brachiocephalic Veins
At which vertebral level does the trachea divide into the right and left main bronchi?
T4/T5
Which nerves provide innervation to the diaphragm and its associated membranes?
Phrenic Nerves
Which nerves give rise to the right and left recurrent laryngeal nerves?
Vagus Nerves
Which structure is highly susceptible to compression by a pathologic mass, leading to vocal cord paralysis and hoarseness of the voice?
left laryngeal nerve
Which part of the esophagus is compressed by the left main bronchus?
Where the arch of aorta crosses esophagus
Which arteries supply the bronchi and lungs?
Bronchial arteries
Which veins form the azygos system of veins?
Azygos vein and accessory hemiazygos vein
Which veins drain into the superior vena cava?
Right superior intercostal vein and left brachiocephalic vein
During blockage of the inferior vena cava, venous return from the lower extremities is accomplished through:
Anastomosis between the superior and inferior epigastric veins and the superficial epigastric vein and the lateral thoracic vein
Where does the thoracic duct empty into?
Left subclavian and left internal jugular veins
What is the function of the azygos vein in case of an obstruction of the inferior vena cava?
To reroute blood to the thoracic duct
What is the purpose of the collateral venous circulation?
To facilitate venous return from the lower extremities during blockage of the inferior vena cava
Study Notes
Thymus and Mediastinum
- The thymus is located in the superior mediastinum, anterior to the trachea and great vessels.
- The main artery in the superior mediastinum is the brachiocephalic artery.
- The phrenic nerves and vagus nerves are found in the superior mediastinum.
Thymus Development and Function
- The thymus atrophies and decreases in size after puberty.
- The thymus is located immediately anterior to the trachea.
Trachea and Bronchi
- The trachea divides into the right and left main bronchi at the level of the fifth thoracic vertebra (T5).
- The right and left recurrent laryngeal nerves branch from the vagus nerve and provide innervation to the intrinsic muscles of the larynx.
Esophagus and Bronchi
- The left main bronchus compresses the esophagus.
Blood Supply and Venous Drainage
- The bronchi and lungs are supplied by the bronchial arteries, which arise from the thoracic aorta.
- The azygos vein, hemiazygos vein, and accessory hemiazygos vein form the azygos system of veins, which drain into the superior vena cava.
- The azygos vein provides a collateral pathway for venous return in case of inferior vena cava obstruction.
- In case of inferior vena cava blockage, venous return from the lower extremities is accomplished through the collateral venous circulation, which drains into the azygos vein.
Lymphatic System
- The thoracic duct empties into the junction of the left subclavian and internal jugular veins.
Test your knowledge of the mediastinum and its contents with this quiz. Learn about the regions, vasculature, branches of the thoracic aorta, phrenic and vagus nerves, and the azygos system. Put your understanding to the test now!
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
