Lymph and lymphatic system
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The document provides an overview of the lymphatic system, including its history, development, components, and functions. It discusses how the lymphatic system developed from lymph sacs in the embryo and transformed into nodes. The key components are lymphatic capillaries that collect fluid from tissues, vessels that connect to nodes, ducts like the thoracic duct that return lymph to blood circulation, and lymphoid organs like the thymus, bone marrow, spleen and nodes that help fight infection. The lymphatic system works to remove excess fluid, distribute nutrients, and fight pathogens throughout the body.
Lymph and lymphatic system
- 1. AN OVERVIEW OF LYMPHATIC SYSTEM Dr.N.R.K.Anil Kumar, Dept.Of Oral and Maxillofacial Surgery, Vishnu Dental College, Bhimavaram LYMPHATICS OF HEAD AND NECK
- 2. CONTENTS • History • Development of lymphatic system • Lymphatic system • Lymph • Lymphatic Channels • Lymph node • Lymphoid organs • Lymph nodes of head and neck • Diseases of lymphatic system
- 3. HISTORY • Ancient greeks Hippocrates and Aristotle described lymph as white fluid. • Gasparo aselli an italian anatomist discovered lymphatic vessels in 1622. • Van hook in 1652 demonstrated the presence of cisterna chyli and thoracic duct in humans.
- 4. • William hunter in the late 18th century was the first to describe the functions of lymphatic system. • Olof Rudbeck of swedish university described that lymphatic system constitute a circulatory system separate from blood circulation and this fact was accepted by Royal society of London.
- 5. DEVELOPMENT • Develop at the end of 5th wk of embryonic life • Lymphatic vessels develop from lymph sacs which arise from developing veins and are derived from mesoderm • 1st lymph sac to appear paired jugular lymph sacs at junction of internal jugular & subclavian veins
- 6. DEVELOPMENT
- 7. • JUGULAR LYMPH SACS • Retains one connection with its Jugular vein • Spreads lymphatic capillary plexuses to Thorax , upper limbs , head &neck. • Left one develops into superior portion of thoracic duct. • RETROPERITONEAL LYMPH SAC • It is unpaired and develops from primitive vena cava & mesonephric veins. • Spreads capillary plexuses & lymphatic vessels to abdominal viscera & diaphragm. • Develops connections with cisterna chyli & loses connections with neighboring veins
- 8. CISTERNA CHYLI • develops inferior to diaphragm on post abdominal wall. • gives rise to inferior portion of thoracic duct. POSTERIOR LYMPH SACS • Develops from iliac veins. • Gives capillary plexuses & lymphatic vessels to abdominal wall , pelvic region & lower limbs. • Join cisterna chyli & loose connections with adjacent veins
- 9. Development • Lymph vessels grow out from the lymph sacs, along the major veins. • Except for the upper portion of the cisterna chyli, which persists, the lymph sacs are transformed into groups of lymph nodes during early fetal life, at about 3 months.
- 10. Development • PALATINE TONSILS – second pair of pharyngeal pouches • TUBAL (PHARYNGOTYMPANIC) TONSILS - aggregations of lymph nodules around the openings of the auditory tubes • PHARYNGEAL TONSILS (adenoids) - aggregation of lymph nodules in the nasopharyngeal wall • LINGUAL TONSILS - aggregations of lymph nodules in the root of the tongue • LYMPH NODULES also are seen in the mucosa of the digestive tract and respiratory tract • SPLEEN - aggregation of mesenchymal cells in the dorsal mesentery of the stomach
- 11. LYMPAHATIC SYSTEM • Lymphatic comes from the Latin word lymphaticus, meaning "connected to water," as lymph is clear. • Network of vessels & lymph nodes which are located in all major tissues of body. • Lymphatic system is absent in CNS, Cornea, Superficial layer of skin, Bones, Alveoli of lung. • CONSIST OF – Lymph – Lymphatic Channels – Lymph Nodes – Lymph Organs Capillaries Vessels Ducts
- 12. LYMPH Lymph is • Transudative fluid. • Transparent & slightly yellowish liquid. • Alkaline in nature. • Derived from tissue fluid. • When blood passes through tissues 9/10 of fluid - venous end 1/10 of fluid - lymph capillaries • “CHYLE” - Lymph from small intestine.
- 13. FORMATION OF LYMPH Starling’s hypothesis
- 15. COMPOSITION OF LYMPH PROTEINS : 2 to 6 % of solids. Depending upon the part of body from which it is collected Albumin, globulin, clotting factors (fibrinogen, prothrombin) , all antibodies and enzymes. LIPIDS : 5-15 % - mainly chylomicrons and lipoproteins. CARBOHYDRATES : Sugar - 132 mg per 100 ml (Mainly glucose). Non protein nitrogenous substances : Urea, A.A & Creatinine. ELECTROLYTES : sodium, calcium, potassium, Chloride & bicarbonate. CELLULAR CONTENT : mainly lymphocytes 1000-2000 per cu mm 96% water 4% solids
- 16. RATE OF LYMPH FLOW • Total estimated lymph flow is 120 ml / hr • About 100 ml flows through Thoracic duct in resting man per hour • Approx 20 ml flow into circulation through other channels • 3 – 4 liters / day
- 17. • Lymph carries protein and large particulate matter away from the tissue space. • End products of digestion are absorbed mainly by lymph channels. • Important role in redistribution of fluid in the body. • Bacteria, toxins and other foreign bodies are removed from the tissues. • Maintenance of structural and functional integrity of tissue. • In immune response of the body. • Production and maturation of lymphocytes. FUNCTIONS OF LYMPHATIC SYSTEM
- 19. LYMPHATIC CAPILLARIES • Smallest lymphatic vessels • They begin in the tissue spaces as blind-ended sacs. • These capillaries form plexuses which collect lymph from the interstitial space mark the beginning of lymphatic system
- 20. • They are lined by a single layer of endothelial cells. • These are attached to C.T by anchoring filaments. • The edge of one endothelial cell overlaps the adjacent cell. • Overlapping edge is free to flap inward minute valve. • Permits passage of high molecular weight substance. LYMPHATIC CAPILLARIES
- 21. LYMPHATIC VESSELS • Lymph capillaries merge to form lymphatic vessels. • Resemble veins but – Thin walls (Diameter - 0.2 – 0.3 mm) – More valves (formed from folds of tunica intima) – Lymph Nodes are located at interval along its course Have 3 coats (Tunica intima, Tunica media, Tunica adventitia) BEADED in appearance (semilunar valves). Collagenous fibers attaches the endothelium to the outer tissues ( fibrous sheath of muscle)
- 22. LYMPHATIC DUCTS RIGHT LYMPHATIC DUCT THORACIC DUCT
- 23. THORACIC / LEFT LYMPHATIC DUCT • 38 – 45 cm long • Begins as a dilation called cisterna chyli anterior to 2nd lumber vertebra. • Main duct for return of lymph to blood • Receives lymph from left side of head, neck, Left upper limb, chest & entire body inferior to ribs • Joins the venous system at the junction of Left Sub clavian & Left internal jugular veins & drains lymph via Lt subclavian vein.
- 24. Origin, course, relations, and termination • Arises in the abdomen from cisterna chyli under cover of diaphragm. • Enters the thorax through the aortic opening. • It continues upward through the posterior mediastinum, on the left, first with the aortic arch and then with the left pleura. • It enters the root of the neck, where it arches laterally behind the left carotid sheath, to terminate in the upper end of the left innominate vein, in the angle of junction of the internal jugular and subclavian veins. • Chyle leak. • Virchows or scalene nodes or signal nodes – supra clavicular nodes.
- 25. RIGHT LYMPHATIC DUCT • 1.2 cm long • 3 lymphatic trunks drain into Rt lymphatic duct – Rt Jugular trunk-drains Rt side of head & neck – Rt subclavian trunk-Rt upper limb – Rt bronchomediastinal trunk-Rt side of thorax, Rt lung, Rt side of heart , & part of liver • Rt lymphatic duct joins the venous system at the junction of Rt Sub clavian & Rt internal jugular veins
- 26. LYMPHOID ORGANS
- 27. Primary or Central lymphocytes are produced and undergo development and are supplied to secondary organs. • Thymus • Bone marrow Secondary or peripheral organs : lymphocytes are activated to participate in specific immune response. • Lymph nodes • Spleen • Tonsils LYMPHOID ORGANS
- 28. BONE MARROW • Bone marrow contains two types of cells multipotent stem cells • NON – LYMPHOID STEM CELLS differentiate in bone marrow. • Erythrocytes , granulocytes , monocytes & platelets. • LYMPHOID STEM CELLS differentiate in bone marrow & then migrate to lymphoid tissue. • B & T lymphocytes.
- 30. • T- lymphocytes ( 75-80 %) - based on coreceptor divided into T - helper cells (with CD 4 coreceptors) T - cytotoxic cells(with CD 8 coreceptors) • B- lymphocytes plasma cells memory cells LYMPHOCYTES
- 31. THYMUS • Primary organ of Lymphatic System. • Unpaired organ. • Consists of 2 pyramidal lobes. • Delicate & finely lobulated surface. • Located in mediastinum. • Extending • Upwards - into neck as far as lower edge of thyroid gland • Downwards - as far as fourth costal cartilage • Largest at puberty and weighs 35 to 40 gms - Pinkish grey. • Gradually atrophies in old age- yellowish in colour ( fat).
- 32. FUNCTIONS OF THYMUS - Thymus contains lobes divided into lobules. - Each lobule – cortex ( immature T lymphocytes, Macrophages) – medulla ( T lymphocytes, thymic corpuscels) 1) Processing the “T’’ Lymphocytes 2) Endocrine functions Of Thymus They Secretes Hormones namely A) Thymosin B) Thymin C) Thymic Humoral Factor D) Thymulin
- 33. SPLEEN • Located in left hypochondrium, directly below diaphragm, above left kidney & descending colon & behind fundus of stomach. STRUCTURE Roughly ovoid shape Varies in size in diff individuals Same individuals differs in size from time to time Hypertrophy in infections Atrophies in old age Surrounded by fibrous capsule Its extensions run inwardly roughly dividing the organ into compartments WHITE PULP and RED PULP ( Splenic cords & sinusoids).
- 34. FUNCTIONS OF SPLEEN • DEFENSE : as the blood passes through sinusoids of spleen, microorganism from the blood are destroyed • HEMOTOPOIESIS : monocytes & lymphocytes complete development in spleen • Worn – out RBC & platelets are destroyed • Acts as a RESERVOIR of blood (200-350 ml ) • Main source of circulating antibody in the body.
- 35. LYMPHATIC NODULES • Egg shaped masses of lymphatic tissue not surrounded by capsule. • They are scattered through out the GIT, urinary & reproductive tracts and respiratory airways and are referred to as Mucosa – Associated Lymphatic tissue ( MALT ) • Many lymphatic nodules are small & solitary • Peyers patches • Some occur in multiple aggregation in specific parts of body TONSIL
- 36. In relation to oropharyngeal isthmus , they are several aggregates of lymphoid tissue • Rt & Lf palatine tonsil • Pharyngeal tonsil • Tubal tonsil • Lingual tonsil WALDEYER’S RING
- 37. • Tonsil are located under mucous membrane and back of throat • There are depression of surface epithelium around which aggregate of lymph nodule are grouped called CRYPTS. • Intratonsillar crypt • Peritonsillar abscess begins in this cleft • It is a collection of pus between fibrous capsule of the tonsil usually at its upper pole and the superior constrictor muscle of pharynx. TONSILS
- 38. LINGUAL TONSILS • Hyperplasia is the most common abnormality of the lingual tonsil. • Lingual tonsils sit on the base of the tongue and extend to the vallecula and do not have a capsule. • Can be visualized by indirect mirror or flexible laryngoscopy • Clinically, infection is marked by erythema and enlargement of tonsillar tissue. • Although the lymphoid tissue in Waldeyer's ring tends to decrease with advancing age, the lingual tonsil may increase in size. Important cause of lingual tonsil hypertrophy is the occurrence of compensatory hyperplasia following adenotonsillectomy.
- 39. ADENOIDS • Pathological hypertrophy of nasopharyngeal tonsils. • Mostly between 3 to 5 years of age. CLINICAL PRESENTATION • Nasal obstruction ( mouth breathing, snoring, nasal tone, difficulty while suckling and eating) • Adenoid facies ( elongated, flat, expressionless, without nasolabial folds, open mouth, dry lips, high palate, receded chin
- 40. • Mucopurulent anterior and posterior nasal discharge. • Sleep disturbances (snoring, night enuresis due to hypercapnia ) • Feeding problems ( indigestion, loss of appetite ) • Decreased mental performance • Recurrent ear problems • Respiratory problems
- 41. LYMPH NODES • A normal young adult body contains some 400-450 lymph nodes. •Head and neck -- 60-70 • Arms/superficial thorax – 40 • Legs/superficial buttocks – 30 •Thorax – 100 •Abdomen/pelvis – 230
- 42. LYMPH NODES • Small oval or bean shaped body • Range from 10 to 20 mm in diameter. • Positioned along the course of lymph vessel. • Slight depression called HILUS (blood vessels enter & leave through it)
- 43. MICROSCOPIC STRUCTURE OF LYMPH NODES Each lymph node is enclosed by a fibrous capsule It consist of Capsule, Cortex, Medulla. Fibrous septa or trabeculae extend from covering capsule toward centre of node. Cortical nodule packed lymphocytes surrounded by less dense area Germinal Center Cortical nodules within cortex separated from each other by trabeculae MEDULLA is composed of Sinuses & Medullary Cords
- 44. CELL ZONES IN LYMPH NODES ZONE 1 - is a region of loosely packed cells, predominantly small lymphocytes, macrophages and occasional plasma cells. ZONE 2 - is a denser region internal to zone 1,composed mainly of small lymphocytes and macrophages ZONE 3 - comprises the germinal centers of follicles, its cells include large lymphoblast, dendritic cells and macrophages.
- 45. FUNCTIONS OF LYMPH NODES DEFENSE As lymph passes through lymph Node reticuloendothelial cells remove microorganisms & other injurious particles HEMATOPOIESIS Site for final stage of maturation of lymphocytes & monocytes that have migrated from bone marrow
- 46. CLASSIFICATION OF LYMPH NODES HORIZONTAL CHAIN - Outer circle - Inner circle VERTICAL CHAIN level 1 consist of sub mental, submandibular nodes level 2 consist of upper jugular nodes level 3 consist of middle jugular group level 4 lower jugular group level 5 posterior triangle group level 6 anterior compartment group level 7 superior mediastinal group level 8 supraclavicular nodes level 9 retropharyngeal nodes
- 47. Base of skull Bifurcation of carotid or hyoid bone Inferior border of cricoid cartilage or omohyoid muscle clavicle
- 48. The Lymphatic Drainage of the Tissue of the Head and Neck 1. The superficial tissues 2. The deeper structures and viscera The two layers are separated by deep cervical fascia.
- 49. 1. Lymphatic Drainage of the Superficial Tissues of the Head and Neck Regional lymph nodesSuperficial tissues Deep cervical nodes
- 50. NeckRegional drainage Lymph nodes of Head of superficial tissues and - Occipital - Retroauricular - Parotid - Buccal (facial) - Submandibular - Submental - Anterior cervical
- 51. Occipital lymph nodes Afferent – Back of scalp Efferent – Deep cervical lymph nodes At the apex of posterior triangle, superficial to trapezius
- 52. Retroauricular (mastoid) Lymph Nodes Afferent - Strip of scalp above auricle - Posterior external auditory meatus Efferent - Deep cervical nodes superficial to sternocleidomastoid and mastoid process and deep to auricularis posterior muscle
- 53. Parotid Lymph Nodes - Superficial parotid nodes - Deep parotid nodes Afferent of superficial parotid nodes - Strip of scalp above the parotid salivary gland - Lateral surface of auricle - Anterior wall of external auditory meatus - Lateral part of the eyelid Afferent of deep parotid nodes - Middle ear Efferent - Deep cervical nodes 5 to 6 in number
- 54. Buccal Lymph Nodes Afferent – lower eye lid, part of cheek buccinator muscle, facial vein Efferent - Submandibular lymph node On the surface of buccinator muscle in Relation to facial vein
- 55. Submandibular Lymph Nodes Afferent - Front of scalp - Nose and adjacent cheek - Upper lip - Lower lip ( except center part ) - Frontal, maxillary, ethmoidal air sinus - Upper and lower teeth ( except lower incisor ) - Anterior 2/3 of tongue ( except tip) - Floor of mouth, vestibule, gums - Deep cervical lymph nodesEfferent
- 56. Submental Lymph Nodes Afferent - Tip of tongue - Floor of mouth beneath the tip of tongue - Incisor teeth and associated gum - Center part of lower lip - Skin over chiin Efferent – Submandibular node - Deep cervical lymph nodes (Jugulo-omohyoid nodes)
- 57. Superficial Cervical Lymph Nodes Afferent - Skin over the angle of jaw - Skin over apex of parotid salivary gland and lobule of ear Efferent - Deep cervical lymph nodes
- 58. 2. Lymphatic Drainage of the Deeper Tissues of Head and Neck Deeper tissues of head and neck Regional lymph nodes Deep cervical lymph nodes
- 59. Regional Lymph Node - Retropharyngeal - Paratracheal - Infrahyoid - Prelaryngeal - Pretracheal - Lingual Infrahyoid node Prelaryngeal node Pretracheal node
- 60. Retropharyngeal lymph nodes – Located between pharynx & atlas. – Afferents Pharynx , Auditory tube , Soft palate , post part of hard palate, Nose.
- 61. Paratracheal Lymph Nodes Afferent - Neighboring structures - Thyroid gland Efferent - Deep cervical lymph nodes Paratracheal node
- 62. Infrahyoid,Prelaryngeal,Pretracheal Lymph Afferent – Anterior cervical nodes Efferent – Deep cervical lymph nodes Infrahyoid node Prelaryngeal node Pretracheal node Nodes
- 63. Superior Deep Cervical Lymph Nodes -Jugulodigastric lymph nodes -Located - below posterior belly of digastric , between angle of the mandible & ant border of sternocleidomastoid -One larger node and few small nodes Afferent – Tongue, tonsil Efferent - Lower deep cervical lymph nodes and Jugular trunk
- 64. Inferiordeepcervical lymph nodes Jugular Omohyoid Located - angle between the Int J V and superior belly of omohyoid Afferent – Tongue & Superficial and superior deep cervical nodes. Efferent - Jugular trunk lymph nodes
- 65. LYMPHATIC DRAINAGE OF FACE – Upper part Parotid Lymph nodes – Middle part Submandibular lymph nodes – Lower part Submental lymph nodes
- 66. Gingiva Submandibular lymph nodes Hard palate Superficial deep cervical and retropharyngeal Soft palate Retropharyngeal Floor of the mouth Submandibular and Submental Teeth Submandibular and deep cervical submental Tonsil Jugulodigastric nodes LYMPHATIC DRAINAGE OF MOUTH, TEETH, TONSIL
- 67. Tip Submental Anterior 2/3rds Submandibular & deep cervical Posterior 1/3rd Jugulodigastric lymph nodes LYMPHATIC DRAINAGE OF TONGUE
- 69. LYMPHATIC DRAINAGE OF PARANASAL AIR SINUSES • FRONTAL SINUS SUBMANDIBULAR NODES • MAXILLARY SINUS SUBMANDIBULAR NODES • ETHMOIDAL SINUSES SUBMANDIBULAR NODES • SPHENOIDAL NODES RETROPHARYNGEAL NODES
- 70. DISEASES OF LYMPHATIC SYSTEM • Diseases of Lymphatics • Diseases of Lymph Nodes
- 71. DISORDERS OF LYMPHATICS • Caused --- Haemolytic sreptococci, Staphylococcal infections • Infection occurs - distal limb - spreads to regional lymph. N • Lymph N - enlarged , tender & later abscess may occur – Treatment --- conservative Penicillin --- drug of choice • Caused -repeated attack of Acute Lymphangitis LYMPHANGITIS inflammation of peripheral lymphatics •Appear as red streaks progressing towards regional lymph N Acute Chronic
- 72. LYMPHOEDEMA • Condition in which swelling of tissue in the extremities occurs due to obstruction of the lymphatics & accumulation of lymph • Etiology – Primary lymphoedema – Secondary lymphoedema
- 73. CLASSIFICATION • According to the distribution of edematous fluid: (a) Local edema:(brain edema, pulmonary edema, etc). (b) Generalized edema:(cardiac edema, renal edema). • According to the causes of edema: a) cardiac edema b) renal edema c) hepatic edema d) idiopathic edema • According to the gravity of edema: a) recessive (non-pitting) edema; b) frank (pitting) edema.
- 74. • Frank (pitting) edema: • 99% of interstitial fluid is fixed to collagen, mucopolysaccharide and hyaluronic acid (gel), (connective tissue), which called fixed water. • 1% of interstitial fluid is free water (moving freely).
- 75. Mechanism of edema caused by increased CHP capillary hydrostatic pressure(CHP)↑ effect hydrostatic pressure(EHP)↑ effective filtration pressure(EFP)↑ interstitial fluid ↑.
- 76. Mechanism of decreased COP leading to edema plasma colloidal OP↓ effective COP↓ Effective filtration pressure ↑ Interstitial fluid ↑
- 77. Mechanism of leading to edema in increased permeability of capillary wall permeability of capillary wall ↑ protein and fluid leak to interstitial space tissue COP↑ plasma COP ↓ effective COP↓ effective filtration pressure↑ interstitial fluid ↑
- 78. mechanism of lymph edema obstructed lymphatic vessels backflow of protein in interstitial fluid is blocked, the interstitial COP will increase effective COP decrease effective FP increase more fluid accumulates in interstitial space.
- 79. 3. Characteristics of edema (1) Properties of edematous fluid ------------------------------------------------------------------------------------------ Edematous causes protein appearance specific fluid concentration gravity ------------------------------------------------------------------------------------------ transudate ↑effective filtration 1～2g % clear low pressure exudates ↑permeability of 4g % muddy high vascular wall lymph obstruction of 4～5 % chyliform higher lymphatic vessel -----------------------------------------------------------------------------------------
- 80. • Lymphoedema Congenita – Oedma present at birth – Occurs ---- 10 % of cases • Lymphoedema Parecox – Starts at adolescents ( 15 – 25 age ) – Occurs ---- 75 % of cases • Lymphoedema Tarda – Occurs after 35 yrs – Seen in 15 % of pts PRIMARY LYMPHOEDEMA Developmental error of lymphatic system 3 types
- 81. SECONDARY LYMPHOEDEMA • Caused - Neoplastic / inflammatory process • Surgical excision / Radiotherapy • Parasitic infection with Filariasis
- 82. DISORDERS OF LYMPH NODES • Lymphadenities ---- due to primary inflammatory reactions • Lymphadenopathy ---- due to primary immune reactions • LYMPHADENITIES – Acute – Chronic
- 83. ACUTE LYMPHADENITIES – All kinds of acute inflammation – Common causes • Microbiological infections • Foreign body in wound – Nodes ---- enlarged , tender , may be fluctuant , over lying skin is red hot. CHRONIC LYMPHADENITIES – Commonly called --- Reactive lymphoid hyperplasia – Cause --- repeated attacks of acute lymphadenities lymph from malignant tumours
- 84. EXAMINATION OF LYMPHNODES • Normal lymph node --- Non palpable • Inspection : – Swelling --- Number, position ,size – Skin over swelling --- • Acute lymphadenites --- inflamed , red , edema • Chronic lymphadenites --- no change • T B & Cold abscess --- skin is cold • Lymphosarcoma --- tense , shining with dilated subcutaneous veins
- 85. PALPATION : – Number, size , tenderness , local temp , surface margins , consistency , fixation to underlying tissues • Acute infection --- large, soft, painful, mobile, • Chronic infection --- large, firm, less tender, mobile • Lymphoma --- rubbery hard, matted, painless and multiple • Metastatic cancer --- stony hard, fixed to the underlying tissues, painless. • Syphilis --- Firm discrete shotty • Tuberculosis- Stage I: Lymph nodes enlarged without matting Stage II: Lymph nodes enlarged with matting Stage III: Cold abscess
- 86. LYMPH NODE EXAMINATION • Pt relaxed & unstrained position with out head support • Depending on site – Bilateral ---- behind pt – Unilateral ---- front of pt • Palpation is done by placing flat surface of finger tips at same position on both sides • Commencing with most superior nodes & working down to the clavicle
- 87. • Lymphography • valuable tool for detection of lymphatic fistulas and lymphatic leakage • Ethidiol • Lymphangioscintigraphy • Tc-99m albumin –intradermally, and after 1 minute and again after 10–30 minutes, • High-resolution scintiscan camera • Ultrasonography • Computed Tomography • PET • MRI (MR lymphography) • Fluorescein Microlymphangiography (isothiocynate) • BIOPSY INVESTIGATIONS
- 88. Thank you .