Lymphatic drainage routes Flashcards
How many lymph nodes does the body contain?
500 Lymph nodes
What is the classic rule of lymph drainage?
Lymph drainage mostly follows the route of arterial supply
lymphoid tissue forms aggregations at body entrances.
What are the constituents of lymphatic fluid?
Protein, fat (chyle from intestine) salts, glucose, white blood cells
Similar to compostion of blood plasma
what do lymphatic vessels contain?
Valves, there is a unidirectional flow of fluid
What are lymph nodes?
Lymph nodes are encapsulated filters; areas of antigen presentation and centres of lymphocyte activation, differentiation and proliferation.
Describe the structure of a lymph node
Lymphatic fluid comes in at the top via afferent lymphatic vessels, flows down through the node, passing through the upper part of the lobe, particularly where lymphocytes sit in a primary lymphoid follicle.
Lymphatic fluid passes through a cortex, paracortex, and medulla before exiting at the hilum into the efferent lymphatic vessel.
Lymph node is both encapsulated by a capsule and segmented by trabeculae.
Why do lymphatic vessels follow the arterial supply?
How do lymphatic vessels develop?
Lymphatic vessels follow arterial supply as the pulsation of the arteries aids the return.
Lymphatic vessels develop with the vascular system and are similar to veins (thin walled and most contain valves).
Where do lymphatic networks drain into? (Two main points)
Describe the distribution of lymphatic drainage of the body noting the key lymph vessels and what regions drain to where
What structures drain to both L and R sides? Why is this clinically important?
The lymphatic networks drain into the venous system in the left and right inferior neck (only two points in the entire body where lymph re-enters the venous system).
- Majority of the body and some of the lungs drain into the left subclavian vein via the thoracic duct.
- Thoracic duct runs up through the thorax and drains to the left subclavian vein.
- Regions drained are: Left side of head, left neck, left upper thorax, left arm, all of abdomen and below.
- The rest of the lymphatics drain into the right lymphatic duct
- Note: Lungs and spinal structures drain to both the L and R
- Clinically important: lung cancer first presentation can be nodes on both L and R
What do lymph nodes form?
What do node groupings define?
Lymph nodes form a continuous network within the body
Node groupings define common points of location of multiple nodes.
What are some important lymph node groupings?
- Pericranial ring at the base of the head
- The cervical nodes along the course of the internal jugular veins
- Axillary nodes within axilla
- Tracheal nodes related to both trachea and bronchi
- Deep nodes related to the aorta and the celiac trunk/ SMA/IMA
- Inguinal nodes along course of inguinal ligament
- Femoral nodes along femoral vein
- Note these are not anatomical groupings but are where they most likely sit.
Where is there an extensive lymphatic network in the skin and why?
There are multiple cutaneous lymph channels within the skin, makes sense as this is the first immune barrier.
Where do lymphatic vessels of the skin and subcutaenous tissue pass to?
What are the 4 key groups where lymph from the limbs drain?
Lymphatic vessels of the skin and subcutaneous tissues pass to nodes located within the groin/ axilla/ elbow/ knee
Often represent regions where the superficial veins drain deep and often drain to where a limb joins the body.
Where do the cubital lymph nodes sit around?
Name the structures shown
When might the lymph nodes shown enlarge?
The cubital lymph nodes sit around the medial epicondyle. Flow of lymph drainage is towards the brachial and axillary lymph nodes. Cubital lymph nodes receive lymph from the forearm and hand on the ulnar side.
Structures shown from R to L: 1) Cubital lymph nodes 2) Basilic vein 3) median cubital vein 4) cephalic vein
Enlargement of cubital lymph nodes usually due to generalised lymphadenopathy, sometimes due to pathology in the hand and forearm.
Which parts of the body drain to the left subclavian vein?
Most of the body and left upper lobe of the lungs drain to left subclavian vein via thoracic duct
Which parts of the body drain to the right lymphatic duct?
Right upper limb
lungs except left upper lobe
right half of face and head
right half of thorax and back
What is lymphangitis?
What should you check when lymphangitis is present?
Lymphangitis is an inflammation/ infection of lymphatic channels due to infection distal to the channel.
Always check distal to the lymphatic channel
Where do lymphatic vessels of the skin run?
Lymphatic vessels from the skin run with cutaneous veins that run to nodes located at the point at which the cutaneous vein joins deep fascia.
What can lymphanigitis be confused with?
Lymphangitis can be confused for thrombophlebitis
Thrombophlebitis is an inflammatory process that causes a blood clot to form and block one or more veins often in legs. Can be a superficial vein or deeper vein (DVT)
What do lymph vessels in the legs run with?
Lymph vessels in the legs run with the great and short saphenous veins to nodes located in the popliteal fossa (short saphenous vein) or inguinal region (great saphenous vein).
What is shown?
Hookworm infection
What are the two groups of superficial inguinal lymph nodes?
superficial inguinal lymph nodes arranged in two groups: Horizontal and vertical
Which perineal structures drain to the superficial inguinal lymph nodes?
Perineal skin
Glans of penis/ clitoris
lower anal/ vaginal canal
anterior labia majora/ scrotal skin
Describe the cutaneous lymph drainage of the abdominal wall
Abdominal wall lymphatic drainage passes to lymph node groups located at the proximal part of the limbs –> Axillary and superficial inguinal nodes
Region roughly split into R and L upper and lower quadrants from umbilicus which acts as a watershed point
describe the route of lymphatic drainage from the iliac vessels
Lymph drains from the ext and int iliac trunks into the R and L lumbar trunks.
Left lumbar trunk also receives lymph from intestinal lymph trunk
R and L lumbar trunks drain into the cisterna chyli in the abdominal cavity
Cisterna chyli becomes thoracic duct within thorax and receives lymph from intercostal lymph trunks.
Thoracic duct drains into the LEFT subclavian vein
Right side of the body from right thorax/ neck/ head etc drains into the right lymphatic duct and into the right subclavian vein.
Label the image
What is shown?
PET CT of the abdomen showing cancer metastases.
Lymph nodes affected near the descending abdominal aorta and lower down in the mesentery surrounding ileocaecal artery supplying the cecum.
What is the blood supply to the gut tube?
How does this relate to lymph node groups?
Where are lymph nodes receiving GI tract drainage located?
GI tract lymph drainage follows the arterial supply; lymph nodes are also located within the mesentery.
Mesenteric nodes sit in the mesentery around arteries suppling the gut tube
Lymph drains to cisterna chylli to reach the thoracic duct and drain into the left subclavian vein.
Label the image
Label the three nerve plexi
Coeliac ganglia and plexus
Superior mesenteric ganglia and plexus
Inferior mesenteric ganglia and plexus
What is the inferior hypogastric plexus?
What does it supply?
What could damage during surgical resection cause?
The inferior hypogastric plexus is a nerve plexus that lies in the pelvis either side of the internal iliac arteries, formed of parasympathetic pelvic splanchnic nerves(s2-s4) and sympathetic sacral splanchnic nerves. (From symp chain).
In males it supplies: ductus deferens, seminal vesicles, prostate (forms prostatic plexus), penis
In females it supplies: Ovaries, uterine tubes, uterus, cervix, vagina
In both it supplies the bladder.
Damage during surgical resection of lymph nodes (e.g. surgical resection in hindgut neoplasma metastasis):
Can affect the secretory phase of male ejaculation by affecting the sympathetic sacral nerves.
Sympathetic sacral nerves L1/L2 involved in secretion from glands, ductus deferens peristalsis and internal urethral sphincter closure.
What is shown on the image?
What structures may be compressed by this pathology?
Mediastinal lymph adenopathy
What is the rule of thumb for lymph drainage of the lungs?
Describe the lymph drainage of the lungs
Lymph drainage of the lungs passes to nodes situated along the tracheobronchial tree.
Hilar (bronchopulmonary) nodes –> Subcarinal nodes –> paratracheal nodes
On the left –> thoracic duct –> drains to left subclavian vein, may primarily take lymph from left upper lobe
On the right –> drains to right subclavian vein –> takes the rest of lymph from the lung
What structure has been compressed in this patient?
The superior vena cava (venous drainage from the upper body and upper limbs has been prevented).
The superior VC although seemingly a large structure can be compressed by lymphadenopathy, cancer, or abruptly in thrombotic cases.
What is the relevance of the pectinate line of the anal canal in terms of lymph drainage?
Where do ovaries/ testicles drain lymph to?
Pectinate line formed by ectoderm (skin) meeting endoderm.
Lymph below pectinate line drains to superficial inguinal lymph nodes
Pelvic organs (and lymph above pectinate line) drain lymph to internal iliac nodes.
Ovaries/ testicles drain lymph to paraortic lymph nodes (L2) following arterial supply (by testicular/ ovarian arteries that come off aorta around L2).
Axillary and breast lymphatics:
What is the lymphatic drainage of the breast?
- Nipple, areolar and breast tissue drains mainly to the axillary and parasternal nodes.
- Anterior (pectoral) and central axillary nodes mainly receive breast lymphatic drainage. (From lateral portion of breast)
- Small proportion from medial breast to the parasternal lymph nodes.
- Numerous additional routes of lymphatic drainage exist:
- Interpectoral (rotter) nodes (between pectoral muscles)
- Contralateral parasternal nodes (most drainage to ipsilateral side)
- Contralateral breast
- subdiaphragmatic / hepatic nodes
- Inguinal lymph nodes
Describe lymph drainage to the axillary lymph node groups
Where does breast skin drain to?
Breast SKIN drains to axillary, infraclavicular (deltopectoral) and deep cervical nodes.
What can be a consequence of gross enlargement of axillary nodes?
Brachial plexus sits in close proximity to the axillary lymph nodes, enlargement can cause brachialplexopathy.
What can result from blockage or removal of lymph tissue?
Lymphoedema can result from blockage or removal of lymph drainage route.
Head and neck lymphatics:
Give 4 causes of neck lumps
1) Tumour metastasis or primary
2) Infection
3) Lymphadenopathy
4) Branchial cyst
Why should you always check systemically for regional lymph node enlargement?
You should always check systemically for regional lymph node enlargement as it may indicate systemic problems
E.g. case of acute lymphoblastic leukaemia, young boy presenting with neck and groin lymphadenopathy.
Label the image
What can occur if they increase in size?
Waldeyer’s ring:
Lymphoid collections found at entries in the body:
1) Adenoid/ Pharyngeal
2) Tubal
3) Palatine
4) lingual
Problems: Swallowing difficult, tubal increase will block eustachian tube affecting middle ear drainage.
