Lymphatic system and spleen Flashcards
(17 cards)
Lymph node:
1 - 3 main structures
2 where are B cells located in a lymph node
3 where are T cells located in a lymph node
1 cortex, paracortex hilum
2 lymphoid follicles (clusters of lymphocytes) in cortex - B lymphocytes develop here.
In medulla, near hilum, are concentrated more B lymphocytes
3 thymus dependent T cells are located in paracortex
Spleen: 1, 3, 5, 7, 9, 11?
1x3x5 inches
weighs 7 ounces (198.5g)
lies between ribs 9 and 11
Lymphatic drainage of stomach: [follows arteries] general rule and 2 exceptions. where does drainage go?
nodes are named after arteries, exceptions:
1 pancreaticosplenic nodes along splenic artery
2 superior and inferior pyloric nodes above and below pylorus
lymphatic drainage follows posterior abdominal wall drainage
Drainage of anterior abdominal wall: [follows veins] above transabdominal wall (superior) and below transabdominal wall (inferior)
above: axillary nodes (follows thoraco-epigastric veins)
below: superficial inguinal nodes (follows superficial epigastric veins)
What is Waldeyer’s ring?
an interrupted circle of protective lymphoid tissue at the upper end of the respiratory and alimentary tract
comprised of:
- lingual tonsil
- palatine tonsil
- tubul tonsil
- pharyngeal tonsil
Histological structure of the spleen:
1- 3 main structures
2 - 2 components of spleen and role of each
3 - where are t cells located in the spleen
1 capsule (thick CT), hilum and trabeculae connecting the two
2
- red pulp: sinusoids that carry blood - old and damaged red cells are filtered out in the sinusoids
- white pulp: lymphoid follicles. Through each follicle pass central terminal arteries called penicillary arteries
3 T cells are located in the immediate periarteriolar region
Characteristics of breast cancer metastasis (5)
1 The breast is divided into 4 quadrants centered on the nipple. Generally, each quadrant metastasizes first to the nodes closest to it.
2 lymphatics of the have no valves. Therefore, can flow in reverse direction
3 axillary and infraclavicular nodes represent 75% of breast’s lymphatic drainage
4 cancers may metastasize through the linea alba into peritoneal cavity
5 tumour cells may be carried by posterior intercostal veins to azygous veins and then to internal vertebral venous plexus. Typically, this presents as secondaries in the thoracic spine (very often at T5) and also explains metastases to brain
Outline mechanism of lymph flow (2), general rules of lymphatic flow
1 interstitial pressure opens gaps between endothelial cells lining lymphatic capillaries
2 arterial pulsations, body movements, respiratory movements allow lymph to move - assisted by unidirectional valves
General rules:
- superficial lymphatics follow veins
- deep lymphatics follow arteries
- mainly unilateral
- CNS has no lymphatic drainage
What divides superior and inferior cervical chain of neck?
What node is commonly enlarged in tonsilitis and where does it sit?
What disease is normally associated with enlarged occipital nodes?
SCM
Jugulodigastric node - at carotid pulsation just above SCM muscle - drains the tonsils
rubella
Lymphatic drainage of breast: lymph follows veins (superficial)
Laterally: axillary
Medially: internal mammary
Inferiorly: abdominal and intra-abdominal lymphatics
Superiorly: infraclavicular and supraclavicular
Posteriorly: interpectoral nodes (between pectoralis major and minor)
4 roles of spleen
1 haemopoeisis in the fetus
2 RBC breakdown
3 immunological: contains both T and B lymphocytes
4 storage of platelets
Role of lymphatic vessels (4)
1 circulate lymphatic fluid
2 drainage of fluid from “third space”
3 removal of osmotically active molecules
4 transport of dietary fat
Differentiate lymphatic vessels from lymphatic plexuses
Lymphatic plexuses:
- network of lymphatic capillaries that originate blindly in extracellular spaces of most tissues
Lymphatic vessels:
- thin walled, valved vessels that are found wherever blood vessels are found
Lymphatic drainage of the pelvis: [follows arteries] where do ovaries drain? where does uterus drain?where does cervix drain? where does vagina drain? where does rectum drain? what about beneath dentate line?
ovaries darin to para-aortic nodes (following gonadal arteries), directly to ipsilateral external iliac nodes, across to contralateral and to medial superficial inguinal nodes (follows round ligament)
uterus drains directly to external iliac nodes, internal inguinal nodes (following uterine artery), medial superficial inguinal nodes (following round ligament)
cervix drains to internal iliac nodes (following uterine and vaginal arteries) and external iliac nodes
vagina drains with bladder to internal iliac nodes (vaginal artery) and external iliac nodes
rectum drains to pararectal nodes and presacral nodes, the internal iliac nodes (middle and inferior rectal arteries) and the inferior mesenteric nodes (superior rectal artery)
beneath dentate line, medial superficial inguinal nodes (following deep external pudendal veins)
Lymphatic drainage of the lungs (3 key points)
1 runs with arteries and bronchi. from visceral pleura to hilum. At the hilum lie the broncho-pulmonary (hilar) nodes
2 left superior lobe is drained by left broncho-mediastinal trunk. The rest of the lungs are drained by the right broncho-mediastinal trunk.
3 broncho-mediastinal trunks drain into respective subclavian veins
Blood supply and drainage of spleen and lymphatic drainage
Blood supply: sole supply from splenic artery - branch of coeliac
Drainage by splenic vein which joins SMV at origin of portal vein
Lymphatic drainage from nodes to retro-pancreatic nodes and then to coeliac nodes
Drainage of posterior abdominal wall: [follows arteries] follow path from abdominal aorta to L subclavian vein
1 anterior branches of abdominal aorta drain into pre-aortic nodes: coeliac, superior & inferior mesenteric and common iliac. then drain into lateral aortic nodes
2 lateral branches of abdominal aorta drain into lateral aortic nodes which then drain into lumbar lymphatic trunk
3 lumbar lymphatic trunk drains into cisterna chyli then to thoracic duct and finally L subclavian vein
