This article needs additional citations for
verification. (September 2014) |
Mediastinum | |
---|---|
Details | |
Identifiers | |
Latin | mediastinum [1] |
MeSH | D008482 |
TA98 | A07.1.02.101 |
TA2 | 3333 |
FMA | 9826 |
Anatomical terminology |
The mediastinum (from Medieval Latin: mediastinus, lit. 'midway'; [2] pl.: mediastina) is the central compartment of the thoracic cavity. Surrounded by loose connective tissue, it is an undelineated region that contains a group of structures within the thorax, namely the heart and its vessels, the esophagus, the trachea, the phrenic and cardiac nerves, the thoracic duct, the thymus and the lymph nodes of the central chest.
The mediastinum lies within the thorax and is enclosed on the right and left by pleurae. It is surrounded by the chest wall in front, the lungs to the sides and the spine at the back. It extends from the sternum in front to the vertebral column behind. [3] [4] It contains all the organs of the thorax except the lungs. [4] [5] It is continuous with the loose connective tissue of the neck.
The mediastinum can be divided into an upper (or superior) and lower (or inferior) part:
Anatomists, surgeons, and clinical radiologists compartmentalize the mediastinum differently. For instance, in the radiological scheme of Felson, there are only three compartments (anterior, middle, and posterior), and the heart is part of the middle (inferior) mediastinum. [7][ page needed]
The transverse thoracic plane, thoracic plane, plane of Louis or plane of Ludwig is an important anatomical plane at the level of the sternal angle and the T4/T5 intervertebral disc. [8] [9] [10] It serves as an imaginary boundary that separates the superior and inferior mediastinum. [8] [9] [10]
A number of important anatomical structures and transitions occur at the level of the thoracic plane, including:
The superior mediastinum is bounded:
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Is bounded:
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Bounded: pericardial sac – It contains the vital organs and is classified into the serous and fibrous pericardium. [4]
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Is bounded:
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The mediastinum is frequently the site of involvement of various tumors:
Mediastinitis is inflammation of the tissues in the mediastinum, usually bacterial and due to rupture of organs in the mediastinum. As the infection can progress very quickly, this is a serious condition.
Pneumomediastinum is the presence of air in the mediastinum, which in some cases can lead to pneumothorax, pneumoperitoneum, and pneumopericardium if left untreated. However, that does not always occur and sometimes those conditions are actually the cause, not the result, of pneumomediastinum. These conditions frequently accompany Boerhaave syndrome, or spontaneous esophageal rupture.
Widened mediastinum | |
---|---|
Other names | Mediastinal widening |
Widened mediastinum in a patient with achalasia |
Widened mediastinum/mediastinal widening is where the mediastinum has a width greater than 6 cm on an upright PA chest X-ray or 8 cm on supine AP chest film. [11]
A widened mediastinum can be indicative of several pathologies: [12] [13]
This article incorporates text in the public domain from page 1090 of the 20th edition of Gray's Anatomy (1918)
This article needs additional citations for
verification. (September 2014) |
Mediastinum | |
---|---|
Details | |
Identifiers | |
Latin | mediastinum [1] |
MeSH | D008482 |
TA98 | A07.1.02.101 |
TA2 | 3333 |
FMA | 9826 |
Anatomical terminology |
The mediastinum (from Medieval Latin: mediastinus, lit. 'midway'; [2] pl.: mediastina) is the central compartment of the thoracic cavity. Surrounded by loose connective tissue, it is an undelineated region that contains a group of structures within the thorax, namely the heart and its vessels, the esophagus, the trachea, the phrenic and cardiac nerves, the thoracic duct, the thymus and the lymph nodes of the central chest.
The mediastinum lies within the thorax and is enclosed on the right and left by pleurae. It is surrounded by the chest wall in front, the lungs to the sides and the spine at the back. It extends from the sternum in front to the vertebral column behind. [3] [4] It contains all the organs of the thorax except the lungs. [4] [5] It is continuous with the loose connective tissue of the neck.
The mediastinum can be divided into an upper (or superior) and lower (or inferior) part:
Anatomists, surgeons, and clinical radiologists compartmentalize the mediastinum differently. For instance, in the radiological scheme of Felson, there are only three compartments (anterior, middle, and posterior), and the heart is part of the middle (inferior) mediastinum. [7][ page needed]
The transverse thoracic plane, thoracic plane, plane of Louis or plane of Ludwig is an important anatomical plane at the level of the sternal angle and the T4/T5 intervertebral disc. [8] [9] [10] It serves as an imaginary boundary that separates the superior and inferior mediastinum. [8] [9] [10]
A number of important anatomical structures and transitions occur at the level of the thoracic plane, including:
The superior mediastinum is bounded:
Contents
|
---|
|
Is bounded:
Contents
|
---|
|
Bounded: pericardial sac – It contains the vital organs and is classified into the serous and fibrous pericardium. [4]
Contents
|
---|
|
Is bounded:
Contents
|
---|
|
The mediastinum is frequently the site of involvement of various tumors:
Mediastinitis is inflammation of the tissues in the mediastinum, usually bacterial and due to rupture of organs in the mediastinum. As the infection can progress very quickly, this is a serious condition.
Pneumomediastinum is the presence of air in the mediastinum, which in some cases can lead to pneumothorax, pneumoperitoneum, and pneumopericardium if left untreated. However, that does not always occur and sometimes those conditions are actually the cause, not the result, of pneumomediastinum. These conditions frequently accompany Boerhaave syndrome, or spontaneous esophageal rupture.
Widened mediastinum | |
---|---|
Other names | Mediastinal widening |
Widened mediastinum in a patient with achalasia |
Widened mediastinum/mediastinal widening is where the mediastinum has a width greater than 6 cm on an upright PA chest X-ray or 8 cm on supine AP chest film. [11]
A widened mediastinum can be indicative of several pathologies: [12] [13]
This article incorporates text in the public domain from page 1090 of the 20th edition of Gray's Anatomy (1918)