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LYMPHATIC SYSTEM

Lymph

Tissue fluid (interstitial fluid) that enters the lymphatic vessels

FORMATION AND TRANSPORT OF TISSUE FLUID

  • Essentially a drainage system accessory to venous system

  • Larger particles that escape into tissue fluid can only be removed via lymphatic system

Functions

  • Network that filters antigens from the interstitial fluid

  • Primary site of immune response from tissue antigens

  • Lymphatic drainage in all organs of the body except brain, eyes, marrow and cartilage

  • Flaccid thin walled channels → progressive caliber

  • 600 lymph nodes in body

  • Slow flow, low pressure system returns interstitial fluid to the blood system

Components of lymphatics

  • Lymph

  • Lymphatic Vessels

  • Lymphatic Organs

  • Lymphatic cells

Lymphatic Capillaries

Features of structure:

  • Blind end

  • Single layer of overlapping endothelial cells

  • More permeable than that of blood capillary

  • Absent from avascular structures, brain, spinal cord splenic pulp and bone marrow

Lymphatic Vessels

  • Three layered wall but thinner than vein

  • More numerous valves than in vein

  • Interposed by lymph nodes at intervals

  • Arranged in superficial and deep sets

Lymph Trunks

  • Right and left jugular trunks

  • Right and left subclavian trunks

  • Right and left broncho mediastinal trunk

  • Right and left lumbar trunks

  • Intestinal trunk

Lymphatic Ducts

  • Right lymphatic duct

  • Thoracic duct

Lymphatic Cells

  • Also called lymphoid cells

  • Located in both the lymphatic system and the cardiovascular system.

  • Work together to elicit an immune response.

Types of lymphatic cells are:

  • Macrophages

  • Epithelial cells

  • Dendritic cells

  • Lymphocytes

Lymphatic Organs

  • Primary organs

    • Red bone marrow

    • Thymus gland

  • Secondary organs

    • Lymph nodes

    • Lymph nodules

    • Spleen

Lymph nodes:

  • Capsular shell

  • Fibroblasts and reticulin fibers

  • Macrophages

  • Dendritic cells

  • T cells

  • B cells

Head & Neck Nodes

Axillary Nodes

Inguinal Lymph nodes

Lymphangitis

  • Inflammation of the lymph vessels

  • Commonest cause bacteria called streptococcus pyogenes(most common).

  • Lymph vessels appear as red streaks through the skin  Lymphangitis

FIlariasis

Lymphedema

  • Occurs due to accumulation of lymphatic fluid in the interstitial tissue

  • Sometimes can be appreciated after wearing tight clothing or jewelry on affected limb

Lymphedema

Lymphadenopathy

  • Means a disease of the lymph nodes

  • Lymph nodes become swollen/ enlarged and may be painful to touch

    Lymphadenopathy

Lymphomas

  • Cancers originating either from the lymphocytes in the lymph nodes or the lymphatic tissue in organs

Lymphomas

Tonsillitis

  • Infection of the pharyngeal tonsils

  • Tonsils are swollen, Fever and pain during swallowing usually present

Tonsillitis

M

LYMPHATIC SYSTEM

Lymph

Tissue fluid (interstitial fluid) that enters the lymphatic vessels

FORMATION AND TRANSPORT OF TISSUE FLUID

  • Essentially a drainage system accessory to venous system

  • Larger particles that escape into tissue fluid can only be removed via lymphatic system

Functions

  • Network that filters antigens from the interstitial fluid

  • Primary site of immune response from tissue antigens

  • Lymphatic drainage in all organs of the body except brain, eyes, marrow and cartilage

  • Flaccid thin walled channels → progressive caliber

  • 600 lymph nodes in body

  • Slow flow, low pressure system returns interstitial fluid to the blood system

Components of lymphatics

  • Lymph

  • Lymphatic Vessels

  • Lymphatic Organs

  • Lymphatic cells

Lymphatic Capillaries

Features of structure:

  • Blind end

  • Single layer of overlapping endothelial cells

  • More permeable than that of blood capillary

  • Absent from avascular structures, brain, spinal cord splenic pulp and bone marrow

Lymphatic Vessels

  • Three layered wall but thinner than vein

  • More numerous valves than in vein

  • Interposed by lymph nodes at intervals

  • Arranged in superficial and deep sets

Lymph Trunks

  • Right and left jugular trunks

  • Right and left subclavian trunks

  • Right and left broncho mediastinal trunk

  • Right and left lumbar trunks

  • Intestinal trunk

Lymphatic Ducts

  • Right lymphatic duct

  • Thoracic duct

Lymphatic Cells

  • Also called lymphoid cells

  • Located in both the lymphatic system and the cardiovascular system.

  • Work together to elicit an immune response.

Types of lymphatic cells are:

  • Macrophages

  • Epithelial cells

  • Dendritic cells

  • Lymphocytes

Lymphatic Organs

  • Primary organs

    • Red bone marrow

    • Thymus gland

  • Secondary organs

    • Lymph nodes

    • Lymph nodules

    • Spleen

Lymph nodes:

  • Capsular shell

  • Fibroblasts and reticulin fibers

  • Macrophages

  • Dendritic cells

  • T cells

  • B cells

Head & Neck Nodes

Axillary Nodes

Inguinal Lymph nodes

Lymphangitis

  • Inflammation of the lymph vessels

  • Commonest cause bacteria called streptococcus pyogenes(most common).

  • Lymph vessels appear as red streaks through the skin  Lymphangitis

FIlariasis

Lymphedema

  • Occurs due to accumulation of lymphatic fluid in the interstitial tissue

  • Sometimes can be appreciated after wearing tight clothing or jewelry on affected limb

Lymphedema

Lymphadenopathy

  • Means a disease of the lymph nodes

  • Lymph nodes become swollen/ enlarged and may be painful to touch

    Lymphadenopathy

Lymphomas

  • Cancers originating either from the lymphocytes in the lymph nodes or the lymphatic tissue in organs

Lymphomas

Tonsillitis

  • Infection of the pharyngeal tonsils

  • Tonsils are swollen, Fever and pain during swallowing usually present

Tonsillitis