The lymphatic system
What lymph nodes drain below the umbilicus and the lower limb
The inguinal nodes
When does the thymus start to atrophy
After puberty
Where are the lymphatics that drain the posterior abdominal wall found
Along the aorta Inferior vena cava Iliac vessels External and internal iliac
Function of the peyer's patch
Destroy bacteria and so prevent pathogens from breaching intestinal wall Generate many memory lymphocytes for long term immunity
What does the thoracic duct drain
Drains the rest of the body. Begins in the abdomen as the cisterna chyle
What makes up the superficial component of the lymphatic system
Drains the skin Cervical nodes - drain above the clavicle Axillary nodes - drain below the clavicle up to the umbilicus Inguinal nodes - drain below the umbilicus
Where does the lymph from the deep plexus drain into
drain into the pulmonary nodes within the lung substance. Then into bronchopulmonary nodes in the hilum of lung. Then into the tracheo-bronchial nodes at the bifurcation of trachea , and finally into broncho-mediastinal lymph trunks to end in thoracic duct (left) or in right lymphatic duct (right).
Where does the lymph from the superficial plexus drain into
drain to bronchopulmonary nodes in the hilum of lung.
Where does the right lymphatic duct drain into
Right venous angle - where the right subclavian vein joins with the right internal jugular vein
What is the function of the lymphatic system
Drains the surplus tissue fluid as not all the fluid goes from the arterioles goes back into the venules Draines leaked plasma proteins as well as bacterial and cellular debris An intergral part of the immune sytem - provides defence against microorganisms by producing antibodies and performing phagocytosis Play and unwanted role in providing at least one pathway for the spread of malignancy
What is the function of the lymph nodes
Filter lymph - Macrophages remove and destroy microorganisms and debris Activate the immune system - lymphocytes strategically located to monitor for the presence of antigens
Function of the tonsils
Gather and remove some pathogens entering the pharynx in food or inhaled air
What are the 2 groups of inguinal nodes
Horizontal - runs superficially over the inguinal ligament Vertical - lie along the termination of the greater saphenous vein i.e. in the femoral triangle
What are the axillary lymph nodes
Humeral nodes (lateral) Pectoral nodes (anterior) Subscapular nodes (posterior) Central nodes Apical nodes
Where is the thymus found
Inferior neck and superior thorax deep to the sternum
What does the right lymphatic duct drain
It drains the right upper quadrant of the body - right side of the head, neck, thorax and right arm
What are Peyer's patches
Large isolated clusters of lymphoid tissue located in wall of distal small intestine
Where does the lymphatic drainage of the breast go to
Most of it goes to the pectoral nodes However some can go to the sternal lymph nodes
Different tonsils in the body
Palatine Lingual Pharyngeal (adenoids if enlarged) Tubal tonsils
Are lymph nodes primary or secondary lymph organs
Primary
Function of the spleen
Provides site for lymphocyte proliferation, immune surveillance and response. Blood cleansing functions -->Extracts aged and defective blood cells and platelets -->Macrophages remove debris and foreign matter Stores/release breakdown products of rbc Erythrocyte production (foetus) Stores platelets
Function of the thymus
Secretes thymopoietin and thymosins - cause T lymphocytes to become immunocompetent
Other lymphoid organs include
Spleen Thymus Peyer's patches of the intestine Tonsils/adenoids Myeloid tissue in the bone marrow
What are some of the superficial cervical lymph nodes
Submental Submandibular Tonsilar Pre-auricular Posterior auricular Occipital Posterior cervical Posterior clavicular Superficial cervical
What are the 2 lymphatic plexuses of the lung
Superficial plexus (subpleural): lies under the visceral pleura Deep plexus: Lies along the bronchial tree & pulmonary blood vessels
What is the structural relationsip between the capillary bed of the vascular system and the lyphatic capillaries
The capillaries are anchored to the interstitium using anchoring filament and then form a plexus around the capillary bed
Where does the thoracic duct drain into
The left venous angle
What lymph nodes drain the posterior abdominal wall and where do they drain into
The lumbar lymph nodes They drain into right and left lumbar trunks ( found along side the aorta. These then drain into the cisterna chyle
What lymph nodes drain the abdominal organs and where do they drain into
The pre-aortic lymph nodes which are just anterior to the aorta They drain into the intestinal lymph trunk, this then drains into the cisterna chyle
How is lymph transported through the lymphatic system
There are low pressure conduits Milking action of active skeletal muscles which push the lymph upwards. Valves which stop the backward flow of lymph Pressure changes in the thorax during respiration which causes a negative pressure that draws the lymph upwards Deep lymphatics are bundled in sheaths of connective tissue with arteries and the pulsations promote flow Smooth muscle in walls of trunks and ducts contract rhythmically
What are kerley B lines
These are lines that are seen in chest x-rays as a result of pulmonary oedema. The pulmonary oedema means the lymphatic enlarge as they try to drain away the excess fluid.
What course do the deep cervical vessels take
These drain into the deep cervical nodes which run along the internal jugular vein. The efferent vessels form the right jugular trunk
What is virchows nodes
This is an enlargement of the supraclavicular lymph nodes and develops due to the growth of cancer within the node as a result of lymphatic spread of cancer of the bowel
What course do the superficial cervical vessels take
Vessels enter superficial cervical lymph nodes along the course of the external jugular vein (over the sternocleidomastoid) The efferent vessels from the cervical lymph nodes then drain into the deep lymph nodes
Hierarchy of the lymphatic systems
lymphatic plexuses lymphatic capillaries Lymphatic collecting vessels Lymph nodes Lymph trunks Lymph ducts