By Dr. Amarendra Salapu

1. LYMPHATIC
PATHOPHYSIOLOGY
Dr. Amarendra babu S.S
Narayana Hrudayalaya hospital

2. Contents:
• EMBRYOLOGY
• ANATOMY
• PHYSIOLOGY
• MOLECULAR LYMPHOLOGY
• PATHOLOGY
• LANDMARKS IN LYMPHOLOGY
• LYMPHANGIOSCINTIGRAPHY

3. Introduction
• It is a closed system
• Latin word lympha
• Part of immune system
• Unidirectional vascular system that transports
surplus tissue fluid back to the blood stream.
• Stabilizes parenchymal cellular integrity &
function.

4. Embryological Development -
• At the end of 5 th week
• In 6-9 weeks, local dilatations of the lymphatic
channels form 6 primary lymph sacs occurs.
• 2 jugular lymph sacs
• 2 iliac lymph sacs
• 1 retroperitoneal lymph sac
• 1 cisterna chyli

6. • Development, at about 3rd month.
• Except for the anterior part of the sac that produces the
cisterna chyli, all lymphatic capillary plexuses become
invaded by mesenchymal cells that proliferate and
aggregate to form groups of lymph nodes.
• lymphocyte production do not appear in the nodes until
just before or after birth
Lymph node :

7. Thoracic Duct :

8. Overview of the Lymphatic System
• Lymph fluid
• Lymph vessels
• Lymphatic organs
Lymph nodes
Tonsils
Spleen
Thymus
Components :

9. Lymph :
• The word lymph is derived from the name of the ancient Roman deity of fresh
water, Lympha
• A clear, colorless fluid, similar to blood plasma but low in protein.
• Composition:
Lymph contains white blood cells.
In particular, the lymph that leaves a lymph node is richer
in lymphocytes.
The lymph formed in intestine – chyle, is rich in triglycerides (fat), and
looks milky white because of its lipid content.

11. • formation:

12. Formation of lymph Pressures acting across
Capillary walls :
Outward Cap. Hydrostatic pressure - 17mmHg
Negative interstitial pressure - 7mmHg
Inter fluid osmotic pressure - 4.5mmHg
total outward - 28.5mmHg
Inward Cap. Fluid osmotic pressure - 28.0mmHg
Net difference - 0.5mmHg

13. Macroscopic anatomy :
Lymphatic vessels :
• Lymphatic capillaries
• Lymphatic collecting vessels
• Lymphatic trunks
• Lymphatic ducts
• Accompany and parallel veins in most of
the body
• Not found in nails, hair
• Analogous circulations in brain and retina

14. Lymphatics of the upper limb

15. Lymphatics of the lowerlimb
• Lymph nodes: superficial & deep
Superficial- superficial inguinal LN
Deep- Deep inguinal LN
Popliteal LN
Anterior tibial LN
• Lymphatics : superficial , deep

17. Lymphatic Capillaries :
• Found in most places that contain
capillaries
• Except Bone marrow, Cartilage, CNS,
Cornea, Nails, Spleen
• More permeable than blood capillaries
• Nature of lymphatic capillaries allows
WBC, pathogens, and Cancer cells to enter
easily

18. • Microscopic vessels that collect ISF
• Closed at one end with flap like valve
• One way valve regulated by pressure changes
• Diameter is 10-60 micrometers

19. • lymph capillaries display both open and closed endothelial junctions with prominent
convolutions and can adjust their size and shape
• Basement membrane is tenuous or lacking
• Anchoring filaments
• Terminal lymphatics :
are devoid of smooth muscle and endothelial lining rich in actin contractile protein
Lymphangions :
• Intraluminal bicuspid valves serve to partition the lymphatic vessels into contractile
segments
Ultrastructure:

20. Lymphatic collecting vessels :
• Terminal lymphatics join together to form lymphatic collecting vessels,
diameter is 50-200 micrometers
• Morphologically similar to veins, except contain more valves
• Pass through lymph nodes
• Can be superficial or deep

21. Lymphatic ducts :
• Right lymphatic duct:
• Right side of thoracic cavity
• Drains lymph from right upper limb and right
side of head & thorax
• Drains into right subclavian & internal jugular
vein junction
• Thoracic/left lymphatic duct: largest duct
• Left side of thoracic cavity
• Drains lymph from everywhere else in the body
• Drains into left subclavian & internal jugular
vein junction

22. Functions of the Lymphatic System :
• Returns needed substances to blood
• Excess water & molecules (electrolytes, proteins, fats, etc.)
• Maintains blood volume
• Transportation of potentially harmful substances (pathogens, cancer cell, debris,
etc.) to lymph nodes, to be destroyed & removed and Initiate immune response
when pathogens present
• Exchange of O2,CO2 in the local milieu interieur
Fluid
recovery
Immunity
Lipid
absorption

23. PHYSIOLOGY:
Blood lymph circulatory loop:
• Lymph flow rate at rest is -1.5 to
2.5 L/24 h
• Propulsion of lymph by
1. Spontaneous segmental
contractions
2. Extrinsic haphazard forces
3. Arterial pulsations

24. • Starlings law : increase in lymph formation is accompanied by more
frequent and powerful lymphangion contractions
• Lymphatic trunkal contractions mediated by :
1. Sympathomimetic agents – both alpha and beta adrenergic agonists
2. Arachidonic acid byproducts – thromboxane, prostaglandins
3. Neurogenic
4. Pacemaker stimuli

25. • Resistance to flow in lymphatic vessels is high in comparison to
venous system, to overcome this impedance, pumping capacity of the
lymphatics should generate intraluminal pressure upto 30-50 mm hg.
• Lymphatic ejection force is modulated not only by filling pressure but
also by temperature, sympathomimetics, neurogenic stimuli,
circulating hormones and locally released cytokines

26. • Normally Venous return is directly enhanced by truncal compression
from skeletal muscle and other adjacent structures, but no effect on
lymph return
• Muscular contraction and external massage clearly accelerates lymph
return in the presence of oedema
• During exercise, muscles are in contraction phase, lymph will be
pushed to an alternative lymphnode through the lymph vessels

27. • Exercise routine should include combination of aerobic, strength and
flexibility types – active, repetitive, non resistive motion of involved
body part
• In manual lymphatic drainage, massaging an intact section adjacent
to the section that includes the affected limb or body part – redirect
lymph fluid toward functioning lymphatic territories

28. • Column of liquid is incomplete in peripheral lymphatics unlike
peripheral veins.
• Effect of external compression on peripheral lymphatics :
1. Normal lymphatic pressure – ineffective in propelling lymph
2. In obstruction – acts as effective pumping mechanism

29. • External compression- 1. compression bandaging 2.compression
garments 3.compression devices
• Goal is to create a internal pump like action
• two types of pressures, low resting pressure(20-30mmHg) and high
working pressure during muscle contraction
• Highest compression that can be tolerated by the patient is likely to
be the most beneficial : 30-40 mm Hg

30. • Intermittent pneumatic compression:
Ideal alternative to replace MLD
Multi-compartment sequential compression achieves best limb
reduction

31. • Effect of gravity on peripheral lymphatics :
erect position – in normal conditions- sharply raises distal venous
pressure but peripheral intra-lymphatic pressure is unaffected, but
lymphatic trunkal pulsation increases in both frequency and amplitude.
This favours removal of tissue fluid during dependency

33. Pathology
• Lymphedema :
Imbalance between the uptake and the transport capacity of the
lymphatic system
Pathology is mainly linked to lipid and protein malabsorption, defected
immunological response and inability to return lymph back to systemic
circulation

35. • Primary :
Sporadic
Genetic disorders- Milroy’s disease (VEGFR3, VEGF-C)
Meige’s disease
lymphedema-distichiasis syndrome(FOXC2)
Cholestasis-lymphedema(LSC1)
Chromosomal aneuploidies- Turner, Klinfelters, Trisomies 13,18,21
Others- Noonans, KTS, PWS,NF-1, Yellow nail syndrome

38. Pathogenesis and sequelae of primary
lymphedema

39. • Progressive truncal tortuosity and dilatation – massive lymphangiectasis –
valvular incompetence – retrograde dermal backflow
• Characteristic trophic skin changes – thickened toe skin folds or stemmer
sign, warty growth, brawny induration, square toes, buffalo hump, woody
texture
• Microscopy discloses mononuclear cell infiltration, intra mural destruction
of lymphatic collectors and collagen deposition in the soft tissues

41. Chylous reflux: rupture/exudation , trauma/malignant disease
• chylothorax, chylous ascites, chyluria, chylometrorrhagia and protein losing enteropathy
• Iatrogenic trauma- after aortic reconstructions and after procedures on IVC
short period of conservative management, if it reaccumulates – reoperation and ligation
of the fistula is the most effective treatment
• chylous vesicles, chyledema of lower extremities and genitalia – primary pathology is in
mesenteric or retroperitoneal lymphatics

42. Infection:
• recurrent cellulitis, Erysipelas, recurrent dermatolymphangitis
• Reasons :Defective compliment activation and immunodysregulation,
dampened monocyte function, replacement of lymphnodes by fat
and scar
• Advised bacterial and fungal prophylaxis in endemic filarial regions

43. Fibrosis :
• Sequelae of superimposed infection
• Pathogenetic sequence is still unclear
• Altered cytokine production and immunoreactivity, accumulation of
complexed plasma protein moieties, exerts chemotactic effects –
chronic inflammatory cell infiltration, migration of fibroblasts and
deposition of collagen

44. Adipogenesis:
• Lymph itself stimulatory to fat cells, it causes upregulation of fat
differentiation genes
• Poor prognostic factor for physical treatment
• liposuction

45. lymphatic tumors:
• Lymphedema process itself is the prime cause
• Immunodysregulation underlies a wide range of vasoproliferative
syndromes
• Lymphangiosarcoma/Angiosarcoma – stewart Treves syndrome
• Others : SCC, Kaposis sarcoma, Melanoma, Malignant lymphoma

47. • Current gold standard for lymphatic system imaging
lymphangioscintigraphy
• Before reconstructive lymphatic surgery : direct contrast
lymphangiography

50. Thank you