The basics<\/h3>\n<\/span>\n\n<\/span>\nComponents<\/h4>\n<\/span>\n\n\n- The fluid that flows through this system is known as lymph<\/strong> and consists of fluids filtered from the extracellular matrix \u2014 mostly from the blood.<\/li>
- Lymphoid organs<\/strong> are divided into primary <\/strong>and secondary<\/strong>:
- Primary lymphoid organs include those where immune cells divide and develop: the bone marrow<\/strong> and thymus<\/strong>.<\/li>
- Secondary lymphoid organs include those where most immune reactions occur: lymph nodes<\/strong>, spleen<\/strong>, tonsils <\/strong>(Waldeyer’s tonsillary ring<\/strong>), MALT <\/strong>(mucous-associated lymphatic tissue<\/strong>).<\/li><\/ul><\/li>
- Lymph nodes <\/strong>are small, bean-shaped structures located in very important locations throughout our bodies, they contain a filtration system consisting of specialized immune cells.<\/li><\/ul>\n\n\n\n
![\"\"](\"https:\/\/meddists.com\/wp-content\/uploads\/2018\/09\/lymphatics-600x468.jpg\")
<\/a>Figure 1. Venous angles and main lymphatic vessels<\/strong> (Credit: OpenStax, CC BY-SA 4.0<\/a>)<\/figcaption><\/figure>\n\n\n<\/span>\nThe lymphatic flow of the body<\/h4>\n<\/span>\n\n\nIn general, all the lymph from the right quadrant of the body drains to the lymphatic trunk<\/strong> (or duct<\/strong>), and the remaining \u00be are to the thoracic duct<\/strong>.<\/p>\n\n\n\n- The final destination for these two vessels are the venous angles <\/strong>(or angulus venosus<\/strong>) which are the joining point of the internal jugular vein and the subclavian vein<\/strong> on each side<\/li>
- As they drain to the venous angle, the lymph re-enters the general circulation<\/li><\/ul>\n\n\n<\/span>\n
Thorax<\/strong><\/h3>\n<\/span>\n\n<\/span>\nThe thoracic duct<\/h4>\n<\/span>\n\n\nThe thoracic duct is the largest lymphatic vessel in the body, originating from the cisterna<\/strong> chyli <\/strong>\u2014 another lymphatic vessel located in the abdomen which ascends via the aortic hiatus<\/strong> (opening for the aorta) of the diaphragm to become the thoracic duct.<\/p>\n\n\n\n- The thoracic duct lies adjacent to a number of structures:
- To its left<\/strong> \u2014 Thoracic aorta<\/li>
- To its right<\/strong> \u2014 Azygos vein<\/li>
- Anterior to it<\/strong> \u2014 Esophagus<\/li>
- Posterior to it<\/strong> \u2014 Thoracic vertebral bodies<\/li><\/ul><\/li>
- Before the thoracic duct ascends into the superior mediastinum, it crosses to the left \u2014 posterior to the esophagus at the level of T4-T5, and sometimes T6 vertebra<\/li>
- The main structures which drain into the thoracic duct are as follows:<\/li><\/ul>\n\n\n\n
- Middle and superior intercostal spaces<\/strong><\/li>
- Posterior mediastinal lymph nodes<\/strong> (read further below)<\/li>
- Superiorly to the mediastinum: Jugular, subclavian,<\/strong> and the bronchomediastinal lymphatic trunks<\/strong><\/li>
- Cisterna chyli<\/strong><\/li><\/ul>\n\n\n\n
- The thoracic duct terminates at the left venous angle <\/strong>near the subclavian and jugular veins point of union.<\/li>
- In some cases, however, it may drain directly into the subclavian vein<\/li><\/ul>\n\n\n<\/span>\n
Posterior mediastinal lymph nodes<\/h4>\n<\/span>\n\n\n- Located in the posterior mediastinum posterior to the pericardium, and surround the inferior part of the esophagus and thoracic aorta<\/li>
- There are about 8 nodes<\/strong> at each side of the esophagus which receive lymph from the following structures:<\/li><\/ul>\n\n\n\n
- Esophagus<\/strong><\/li>
- Middle posterior intercostal spaces<\/strong><\/li>
- The posterior surface of the pericardium<\/strong><\/li>
- Diaphragm<\/strong><\/li><\/ol>\n\n\n<\/span>\n
Lymphatic drainage of thoracic organs<\/h4>\n<\/span>\n\n\nThe lymphatic drainage of each organ is written in the lesson of that specific organ and must be reviewed for this topic:<\/p>\n\n\n\n
- The fluid that flows through this system is known as lymph<\/strong> and consists of fluids filtered from the extracellular matrix \u2014 mostly from the blood.<\/li>
- Lymphoid organs<\/strong> are divided into primary <\/strong>and secondary<\/strong>:
- Primary lymphoid organs include those where immune cells divide and develop: the bone marrow<\/strong> and thymus<\/strong>.<\/li>
- Secondary lymphoid organs include those where most immune reactions occur: lymph nodes<\/strong>, spleen<\/strong>, tonsils <\/strong>(Waldeyer’s tonsillary ring<\/strong>), MALT <\/strong>(mucous-associated lymphatic tissue<\/strong>).<\/li><\/ul><\/li>
- Lymph nodes <\/strong>are small, bean-shaped structures located in very important locations throughout our bodies, they contain a filtration system consisting of specialized immune cells.<\/li><\/ul>\n\n\n\n
<\/a>Figure 1. Venous angles and main lymphatic vessels<\/strong> (Credit: OpenStax, CC BY-SA 4.0<\/a>)<\/figcaption><\/figure>\n\n\n<\/span>\n The lymphatic flow of the body<\/h4>\n<\/span>\n\n\n
In general, all the lymph from the right quadrant of the body drains to the lymphatic trunk<\/strong> (or duct<\/strong>), and the remaining \u00be are to the thoracic duct<\/strong>.<\/p>\n\n\n\n
- The final destination for these two vessels are the venous angles <\/strong>(or angulus venosus<\/strong>) which are the joining point of the internal jugular vein and the subclavian vein<\/strong> on each side<\/li>
- As they drain to the venous angle, the lymph re-enters the general circulation<\/li><\/ul>\n\n\n<\/span>\n
Thorax<\/strong><\/h3>\n<\/span>\n\n<\/span>\n
The thoracic duct<\/h4>\n<\/span>\n\n\n
The thoracic duct is the largest lymphatic vessel in the body, originating from the cisterna<\/strong> chyli <\/strong>\u2014 another lymphatic vessel located in the abdomen which ascends via the aortic hiatus<\/strong> (opening for the aorta) of the diaphragm to become the thoracic duct.<\/p>\n\n\n\n
- The thoracic duct lies adjacent to a number of structures:
- To its left<\/strong> \u2014 Thoracic aorta<\/li>
- To its right<\/strong> \u2014 Azygos vein<\/li>
- Anterior to it<\/strong> \u2014 Esophagus<\/li>
- Posterior to it<\/strong> \u2014 Thoracic vertebral bodies<\/li><\/ul><\/li>
- Before the thoracic duct ascends into the superior mediastinum, it crosses to the left \u2014 posterior to the esophagus at the level of T4-T5, and sometimes T6 vertebra<\/li>
- The main structures which drain into the thoracic duct are as follows:<\/li><\/ul>\n\n\n\n
- Middle and superior intercostal spaces<\/strong><\/li>
- Posterior mediastinal lymph nodes<\/strong> (read further below)<\/li>
- Superiorly to the mediastinum: Jugular, subclavian,<\/strong> and the bronchomediastinal lymphatic trunks<\/strong><\/li>
- Cisterna chyli<\/strong><\/li><\/ul>\n\n\n\n
- The thoracic duct terminates at the left venous angle <\/strong>near the subclavian and jugular veins point of union.<\/li>
- In some cases, however, it may drain directly into the subclavian vein<\/li><\/ul>\n\n\n<\/span>\n
Posterior mediastinal lymph nodes<\/h4>\n<\/span>\n\n\n
- Located in the posterior mediastinum posterior to the pericardium, and surround the inferior part of the esophagus and thoracic aorta<\/li>
- There are about 8 nodes<\/strong> at each side of the esophagus which receive lymph from the following structures:<\/li><\/ul>\n\n\n\n
- Esophagus<\/strong><\/li>
- Middle posterior intercostal spaces<\/strong><\/li>
- The posterior surface of the pericardium<\/strong><\/li>
- Diaphragm<\/strong><\/li><\/ol>\n\n\n<\/span>\n
Lymphatic drainage of thoracic organs<\/h4>\n<\/span>\n\n\n
The lymphatic drainage of each organ is written in the lesson of that specific organ and must be reviewed for this topic:<\/p>\n\n\n\n
- Middle posterior intercostal spaces<\/strong><\/li>
- Esophagus<\/strong><\/li>
- In some cases, however, it may drain directly into the subclavian vein<\/li><\/ul>\n\n\n<\/span>\n
- Posterior mediastinal lymph nodes<\/strong> (read further below)<\/li>
- To its right<\/strong> \u2014 Azygos vein<\/li>
- To its left<\/strong> \u2014 Thoracic aorta<\/li>
- As they drain to the venous angle, the lymph re-enters the general circulation<\/li><\/ul>\n\n\n<\/span>\n
- Secondary lymphoid organs include those where most immune reactions occur: lymph nodes<\/strong>, spleen<\/strong>, tonsils <\/strong>(Waldeyer’s tonsillary ring<\/strong>), MALT <\/strong>(mucous-associated lymphatic tissue<\/strong>).<\/li><\/ul><\/li>
- Lymphoid organs<\/strong> are divided into primary <\/strong>and secondary<\/strong>:
![\"\"](\"https:\/\/meddists.com\/wp-content\/uploads\/2018\/09\/lymphatics.jpg\")
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