Inferior mediastinum Flashcards
What are the two main divisions of the mediastinum?
Superior mediastinum and inferior mediastinum
What anatomical landmark separates the superior mediastinum from the inferior mediastinum?
Transverse thoracic plane
What vertebral junction does the transverse thoracic plane correspond to posteriorly?
T4 and T5
What structures are located in the posterior mediastinum?
- Thoracic aorta
- Thoracic duct
- Lymphatic trunks
- Posterior mediastinal lymph nodes
- Azygos and hemiazygos veins
- Esophagus
- Esophageal nerve plexus
Where does the thoracic aorta begin?
Left side of the inferior border of the body of T4
At what level does the thoracic aorta continue as the abdominal aorta?
T12
What are the vascular branches of the thoracic aorta?
- Esophageal arteries
- Bronchial arteries
- 9 pairs of posterior intercostal arteries
- Subcostal arteries
- Superior phrenic arteries
- Pericardial branches
What anatomical structure does the inferior portion of the esophagus pass posterior to?
Aortic arch
At what level does the esophagus pass through the diaphragm?
T10
Fill in the blank: The inferior vena cava ascends through the diaphragm at level _______.
T8
What phrase can help remember the anatomical landmarks of the esophagus and aorta?
I ate 10 eggs at 12
What three structures cause constrictions of the esophagus in the posterior mediastinum?
- Aortic arch
- Left main bronchus
- Diaphragm
What is the largest lymphatic channel in the body?
Thoracic duct
Where does the thoracic duct typically empty into the venous system?
Left venous angle
What veins comprise the azygos venous system?
- Azygos vein
- Hemiazygos vein
- Accessory hemiazygos veins
What nerve primarily supplies sensory fibers to the pericardium?
Phrenic nerve
What are the two layers of the pericardium?
- Fibrous pericardium חיצוני
- Serous pericardium פנימי
What is the name of the potential space formed between the parietal and visceral pericardial layers?
Pericardial cavity
What arteries supply the pericardium?
- Pericardiophrenic artery
- Musculophrenic artery
- Bronchial arteries
- Esophageal arteries
- Superior phrenic arteries
- Coronary arteries
What is the anterior mediastinum primarily composed of?
- Loose connective tissue
- Fat
- Lymphatic vessels
- Few lymph nodes
- Branches of the internal thoracic vessels
What is contained within the middle mediastinum?
- Pericardium
- Heart
- Roots of great vessels (ascending aorta, pulmonary trunk, superior vena cava)
What are the limits of the posterior mediastinum?
Anterior to T5 through T12 vertebrae, posterior to the pericardium and diaphragm, inferior to the transverse thoracic plane, and between the parietal pleura of the lungs
What do the two rami communicantes of the sympathetic trunk consist of?
- Afferent white rami
- Efferent gray rami
True or False: The sympathetic trunk has one sympathetic ganglion for each thoracic vertebral level.
True
What is the role of the lower thoracic splanchnic nerves?
Supply abdominal viscera
What is the epicardium?
External layer of the heart formed by the visceral layer of the serous pericardium
