Session 3: Lymphatic Drainage Of The Head And Neck Flashcards
What happens to fluid if hydrostatic pressure is greater than oncotic pressure?
Fluid moves from the capillary to the interstitium
T/F: net filtration of fluid is equal to net reabsorption of fluid at the capillaries
False
What is the significance of lymphatic vessels having more porous walls than blood capillaries?
It’s easier for proteins to pass into lymphatics than it is for them to pass back into blood
How much lymph is produced by the body a day?
3-4Litres
What is the importance of lymphatic vessels?
They remove remaining tissue fluid from the interstitium and deliver it back to blood circulation
Why does fluid move from the lymphatics to the venous system?
Venous blood has a lower pressure than the lymph (fluid moves down a concentration gradient)
Why will the flow of lymph slow at the nodes?
Allows for filtration
What are the two lymphatic ducts called?
Thoracic (left) and right
How is unidirectional flow maintained in the lymphatic system?
Valves
Passive and intrinsic constriction
What major vessels do the lymphatic ducts drain into?
Subclavian veins
What causes lymphoedema?
The abnormal collection of protein rich fluid in the interstitium
How can you differentiate lymphoedema from other oedema?
It will pit and is usually unilateral and very large
Describe the structure of a lymph node in regards to CT structures
Tough fibrous outer capsule with reticular connective tissue inside
Give three ways in which lymph nodes provide defence against infection
Physical filter
Phagocytise foreign material
Contain lymphocytes - activated on exposure to foreign antigens
For what two reasons may a lymph node be enlarged?
During an infection
Malignancy
What will an enlarged lymph node in infection feel like?
Tender and mobile
What are the two classifications of lymph nodes?
Regional
Terminal
Give three regions where you can normally palpate lymph nodes
Neck
Armpit
Groin
What separates the regional and terminal lymph nodes in the neck?
The investing layer
Which lymph node drains parts of the eye?
Pre auricular
Where are the terminal lymph nodes of the neck found?
Within the carotid sheath
Name the five superficial lymph nodes of the head
Sub-mental Sub-mandibular Pre-auricular Mastoid (or post-auricular) Occipital
Name three deep cervical lymph nodes
Jugulo-digastric
Jugulo-omohyoid
Supraclavicular
What region do the supraclavicular lymph nodes drain?
The abdominal cavity
