Mediastinum Flashcards
Define the mediastinum
Broad central partition separating the 2 laterally placed pleural sacs/spaces
What is the anterior boundary of the mediastinum
- sternum
- costal cartilages of rib 1-5
What is the posterior boundary/boarder of the mediastinum
-Bodies of thoracic vertebrae
What is the superior boundary/boarder of the mediastinum?
- Thoracic Inlet
(1st rib - laterally)
(Body of T1 vertebrae - posteriorly)
(Sternum - anteriorly)
What is the inferior boarder of the mediastinum?
-Superior surface of diaphragm
What is the lateral boarder of all mediastinal surfaces
Mediastinal pleura (part of parietal pleura)
Describe the MAJOR divisions of the mediastinum and what divides them
- superior
- inferior
Separated by transverse plane from sternal angel to the intervertebral disc between T4 and T5
What are the subdivisions of the Inferior mediastinum
- anterior
- middle
- posterior
Describe the boarders of the superior mediastinum
Anterior:
- Manubrium
Posterior:
- bodies of T1-T4 vertebrae
Superior:
- thoracic I let
Inferior:
- transverse plane separating superior from inferior mediastinum
What STRUCTURES can be found in the Superior Mediastinum? (TOTT)
- Thymus
- Oesophagus
- Trachea
- Thoracic Duct
What MUSCLES are found in the superior mediastinum
- sternohyoid
- sternothyroid
What VESSELS are found in the superior mediastinum?
Arteries:
- aortic arch
- left and right subclavian
- left common carotid
Veins:
- Superior vena cava
- brachiocephalic veins
- left superior intercostal veins
What NERVES are found in the superior mediastinum
- vagus
- phrenic
- left recurrent laryngeal nerves
How is the Anterior Mediastinum identified on a chest X-ray
As the Retrosternal space
By what space of the neck is the anterior mediastinum continuous with the superior mediastinum
Pretracheal space of the neck
Describe the boarders of the Anterior Mediastinum
Anterior:
- body of sternum
Posterior:
- anterior part of pericardium
Superior:
- transverse plane
Inferior:
- Superior surface of diaphragm (T9)
What are the contents of the anterior mediastinum
- lowest part of thymus
- areolar tissue
- sternopericardial ligament
- mediastinal branches of the internal thoracic vessels
