5. Lymph Nodes Of The Head And Neck Flashcards
What 3 things make up the lymphatic system?
Lymph nodes.
Lymphatics.
Lymph.
Where is the lymph system not found?
Eyeball, inner ear, cartilage.
Why doesn’t all the fluid that enters the interstitial space from the arterioles get reabsorbed at the venule side, as the pressures change from high hydrostatic pressure to higher oncotic pressure?
Some small proteins, cell debris and bacteria leak out of capillaries into interstitial space, increasing oncotic pressure here slightly, meaning so fluid is retained.
When does tissue fluid become lymph?
When it moves from the interstitium into a lymphatic capillary.
How much lymph does the body produce a day?
3-4L.
What structures does lymph pass through in it’s uni-directional flow from tissue fluid to the venous system?
Tissue fluid. Lymphatic capillary. Lymphatic vessel. Lymph node. Larger lymphatic vessel. Lymph node. Larger lymphatic vessel. Lymphatic trunks (right and left). Lymphatic ducts (right and left). Venous system.
How does the lymph system ensure unidirectional slow despite the fact it is a low pressure system with no central pump?
Valves.
Passive contraction - due to external compression from pulsation of arteries and muscle contraction.
Intrinsic constriction - constrict in response to stretch.
What veins do the right lymphatic duct and thoracic duct of the lymphatic system drain into?
Right lymphatic duct - into right subclavian vein.
Thoracic duct - into left subclavian vein.
What is lymphoedema?
Abnormal collection of protein-rich fluid causing tissue swelling due to compromised lymphatic system.
Name 3 things that can cause chronic lymphoedema
Removal or enlargement of lymph nodes.
Infections.
Damage to lymphatic system eg cancer treatments.
Lack of limb movement.
Congenital conditions eg Milroy’s syndrome.
Name 3 lymph organs
Spleen.
Tonsils
Thymus.
What types of immune cells do lymph nodes contain?
B and T lymphocytes.
Macrophages.
What type of connective tissue is the outer capsule and inside of a lymph node formed from?
Tough fibrous outer capsule.
Reticular connective tissue inside.
How do lymph nodes act as defect even against infection?
Physical filter.
Phagocytic filter.
Lymphocytes activate and proliferate in response to antigens.
How does an enlarged lymph node due to an infection tend to feel when palpated?
Tender and mobile.
How does an enlarged lymph node due to a malignancy tend to feel when palpated?
Hard, matted, non-tender.
What should you do as a doctor is a lymph node is found to be enlarged in a patient?
Take a comprehensive history.
Examine the area of tissue it drains.
If systemic disease/malignancy suspected examine other lymph nodes and body systems.
What are regional lymph nodes?
Superficial nodes that drain specific areas.
What are terminal lymph nodes?
Deep nodes that receive drainage from a number of regional nodes.
What is a lymphadenopathy?
Enlarged lymph node.
What is the most common cause of swelling in the neck?
Enlarged cervical lymph nodes.
In what layer of fascia are the regional lymph nodes of the neck found?
Superficial cervical fascia.
In what layer of fascia are the terminal lymph nodes of the neck found? What structures are they closely associated with?
Investing layer of deep cervical fascia.
Associated with internal jugular vein, deep to the sternocleidomastoid, within the carotid sheath.
What are the 5 locations of the regional lymph nodes in the head?
Submental. Submandibular. Preauricular. Postauricular. Occipital.
