Lymph Nodes Flashcards
What drives movement of tissue fluid?
Breathing and muscle contraction
Functional importance of lymphatic system?
Assists capillaries in return if plasma proteins that leak into extracellular space
Transport of cellular debris that doesn’t use the circulatory system
Absorbs/transports fats from the digestive system
Fluid balance of the body
Regulation of cell volume
Clinical importance of the lymphatic system?
Conduit for spread of infections and malignancies
Plasma protein return - major constituent of immune system
Site for primary tumours
Blockage leads to lymphoedema
Properties of lymph?
Transudative fluid Transparent and yellowish Alkaline Water makes up 96% Has solute such as proteins, lipids, glucose, electrolytes, cells
How much lymph is produced a day?
3-4L of lymph produced a day at rest
Name the lymph organs
Bone marrow Spleen Thymus gland Lymph nodes Tonsils
What are the main cells in lymph nodes?
Phagocytes and macrophages
Describe the course of lymph fluid
Blind ended lymph channels (microscopic)
Become vessels
Large lymph vessels
Lymphatic trunks
Unite to form either right lymph duct or thoracic lymph duct
Ducts into the venous system at subclavian vein
Which lymphatic duct takes the most lymph?
Thoracic duct - 100ml
Right lymphatic duct only takes 20ml
Which parts of the body does the right lymphatic duct drain?
Right upper part including
- right head
- right neck
- right thorax
- right upper limb
Where does lymph from the right lymphatic duct enter the venous system at?
Right venous angle - at the union of the right internal jugular vein and right subclavian vein
Where is the lymphatic system absent?
CNS Eyeball Inner ear Cartilage Bone
What are the superficial and deep lymph nodes separated by in the head and neck?
Depp fascia of the neck
How are the lymph nodes of the head and neck arranged clinically?
Regional which drain specific anatomical regions
Terminal where the regional ones merge
Regional nodes -> terminal nodes -> trunks -> right/thoracic ducts
Where are the vertical lymph nodes found?
Vertical lane that closely follows course of the internal jugular vein
-difficult to palpate because they are deep in the tissues of the neck
How are the superficial lymph nodes arranged?
Outer circle - collar around the lower margins of the neck. Called peri-cervicular collar nodes from the chin to occipital
Inner circle - lie within outer circle. Surround upper airway passages and openings of alimentary passages. Aka innermost circle
Which lymph nodes are found in the carotid sheath?
Deep/terminal lymph nodes
They surround the whole length of the internal jugular
Start from base of skull to the clavicle
Ultimately drain all lymph from head and neck
Most lymph reaching them has been drained by the inner and outer circles
Where does lymph from the thoracic duct enter the venous system?
Left venous angle - at the union of the internal jugular vein and subclavian vein
How are the lymph nodes of the head and neck grouped?
12 regional groups
1 terminal group aka deep cervical nodes
Name the regional lymph nodes
Occipital Retroauricular aka mastoid Parotid Buccal aka facial Submandibular Submental Anterior Cervical Superficial cervical Retropharyngeal Laryngeal Tracheal
Where are the superficial cervical lymph nodes found?
Along the course of the external jugular vein
Name the lymph nodes in the terminal group
Jugulo-digastric - receives from tonsil and tongue
Jugulo-omohyoid - receives from tongue, oral cavity, trachea, oesophagus and thyroid
What structure do the deep cervical nodes in the posterior triangle of the neck lie close to?
Accessory nerve - may have to be removed in the case of malignancy
Where does lymph from the regional lymph nodes drain to?
Deep cervical lymph nodes - jugular lymph trunks
- > left side joins the thoracic duct -> left brachiocephalic vein
- > right side joins right lymphatic duct -> venous system at junction between the subclavian and internal jugular veins
Where does the thoracic duct begin?
Cisterna chyli at L3
What is lymphadenopathy?
Enlargement of the lymph nodes
What can cause lymphadenopathy?
Malignancy
Infection
On palpation, how can you tell if it’s a malignancy or an infection?
Malignancy
-craggy and not tender
Infection
-tender and smooth
What is glandular fever caused by?
Epstein-Barr virus
-produces atypical lymphocytes
Symptoms of glandular fever?
Swollen, tender lymph nodes
Fever
Fatigue
Sore throat
What is lymphoma?
Solid tumour of lymphoid cells
-B or T cell
Originates in the lymph node
What type of cancer is seen in the majority of head and neck cancers?
Squamous cell carcinoma
What are head and neck cancers associated with?
Smoking
Alcohol
HPV
How does head and neck cancer present?
Lymphadenopathy Mass in the neck Sore throat Dysphagia Hoarseness
Function of lymph nodes?
Phagocytic cells filter out particulate matter and micro-organisms
Antigens are presented to the immune system
What happens in the cortex of lymph nodes?
B cells enter. If activated, they proliferate and become follicle-centres cells.
Take up the antigen, process it and present it to T cells. T cells cause development of B cells by release of cytokines (IL-4) and B cells become centrocytes or centroblasts.
Centroblasts leave the follicle and pass to the paracortex.
Become immunoblasts
What is in the paracortex of the lymph nodes?
Lymphocytes - primary site for T cells. Also accessory cells and supporting cells.
What is in the medulla of the lymph nodes?
Many macrophages
Blood vessels
Medullary cords which are rich in plasma cells
Medullary sinuses
