Date post: | 13-Jan-2016 |
Category: |
Documents |
Upload: | cora-lillian-atkins |
View: | 217 times |
Download: | 0 times |
1
Lymphatic SystemLymphatic System
2
Lymphatic SystemLymphatic System
• Functions
• Return fluid to general circulation
• Production of WBCs
• Immunity
3
Lymphatic VesselsLymphatic Vessels
• Open circulatory system
• Originate blindly in tissue interstices throughout the body except CNS and those without blood supply
• Thin walled - endothelium only
• Permeable
4
Lymphatic VesselsLymphatic Vessels
5
Lymphatic VesselsLymphatic Vessels
• Parallel venous flow
• Asymmetrical distribution
• Two major junctions with cardiovascular system– Thoracic duct into left subclavian vein– Right lymphatic duct into right subclavian
vein
6
DuctsDucts
7
Lymphatic Lymphatic VesselsVessels
8
Lymphatic PhysiologyLymphatic Physiology
• Movement into lymphatic capillaries function of osmotic pressure
• Valves and muscular activity assist return flow
9
Lymphatic OrgansLymphatic Organs
• Lymph nodes
• Spleen
• Tonsils
• Thymus
• Diffuse tissue
10
Lymph NodesLymph Nodes
• Distributed along vascular pathway
• Filter lymph
• Encapsulated by dense CT
• stroma/framework of reticular fibers, trabeculae
• Parenchyma of cortex and medulla
• Lymphocytes/t cells
11
Lymph Lymph NodesNodes
12
Lymph NodesLymph Nodes
• Macrophages• B lymphocytes/b cells• Multiple afferent lymphatics• Usually a single efferent exiting at
hilus/hilum• Size variable 1-25 mm, change with
infection• Secondary tumor sites via metastasis
13
SpleenSpleen
• Functions
• Fetal blood development
• Store and release blood during stress
• Recycle old blood cells
• B cell maturation into plasma cells
14
Spleen StructureSpleen Structure
• 12 cm oval body in left hypochondriac region
• Splenic artery and vein enter at hilus
• Covered with peritoneum
• Structure similar to lymph node
• Parenchyma of two types
15
Spleen StructureSpleen Structure
• Red pulp
• Blood filled venous sinuses
• Splenic cords/Billroth’s cords
• White pulp
• Lymphocyte production
16
TonsilsTonsils
• Aggregated lymph nodes
• Concentrated in Waldeyer’s tonsilar ring– Lingual– Palatine– Pharyngeal/adenoid
17
ThymusThymus
• In superior mediastinum• Two lobes• Surrounded by CT capsule• Cortex = reticular fibers + lymphocytes• Medulla - epithelial cells produce thymosin
stimulating maturation of T cells, form Hassall’s corpuscles
• Maximum size 10-12 yrs old ~ 40 grams, degenerates with age
18
Diffuse Lymphatic TissueDiffuse Lymphatic Tissue
• Not encapsulated
• Widely distributed throughout body
• Found in lamina propria of digestive tract, respiratory, urinary and reproductive systems
19
PathologyPathology
• Lymphangitis
• Lymphadenopathy
• Edema