Chapter 22Lymphatic SystemSection1tion of immunity,clearing and repair.It is composedIntroductionof lymphoid organs,lymphoid tissues, lymphaticThe new research shows that Lymphatic system isvessels and fluids (Fig.I-2-1).Lymph organs includethe saving oneself system in human body and its func-lymph nodes, tonsils, thymus and spleen where largeOccipital lymphnodesMastoidlymphnodesSuperficial parotid lymphnodesSuperficial lateralcervical lymphnodesSubmandibularlymphnodesDeep lateral cervical lymphnodesRight brachiocephalic vSuperior vena cavgHemiazygosv.AxillarylymphnodesThoracicductCubital lymph nodesRight lympaticLumbar lymphnodesIntermal jugular y.ductSubclavianv.Extermal iliaclymphnodesDeepinguinallymphnodesThoracicductSuperficial inguinallymphnodesSuperficiallymphaticvesselfferentlymphatic vesselAfferent lymphaticPoplitealvessellymphnodesLymphnodeArteriole-DeeplymphnodesVenuleCapillaries-PostcapillaryTissue fluidFig. I-2-1 The structure and matchoflymphatic system of human body237扫描全能王创建
·238·PARTIIANGIOLOGYnumbers of lymphocytes gather.While the blood ispassing through the blood capillaries, certain fluidelements filter through the wall of capillaries into thetissue spaces and become the tissue fluid. Most ofthe tissue fluids formed by blood capillaries return toblod circulation,and 10%-20% of these fluids passintolymphvessels andbecomelymph.Lymphistransparentand colorlessexceptforlymphfluids fromintestines which aremilky.The composition of lymphiscloselyresemblesbloodplasma,butwithlowerconcentration of proteins.Lymph passes through oneormore lymph nodes before return to blood circulation,Soas an accessory system ofcardiovascular sys-tem.Iymphaticsystemcantransports andfilterstissuefluids,collects proteins fron tissues,clean up refusemajormolecules,forinstance,germs,virus,alloplasmand death cells etc,repair the tissues and cells whichwere injured,alsoparticipates immune responsesofFig. II-2-2 The comparison of lymphatic capillarylymphocytes.andblood capillaryAs weknow that the natural world is not alwaysso kind tothehuman body.Sometimes the changesThe open and overlapping junctions may be seenof theinternal and external environments often causeon the lymphatic capillary.And blood capillary is inthe various damages. The viruses, bacteria and otherthe right inferior corner.microorganisms may attack ourbody.The lymphaticsystem plays the primary roleto struggle withthese2.Lymphatic vesselsmicroorganisms,and interacts with other systems todefend the body against infection and disease.Lymphatic capillaries unite to form lymphaticvesselswhich resemble veins in structure, buthaveI.Lymphatic Vesselsthinner walls and more valves.In the path of thelymphatic vessels there are number of lymph nodesat various intervals. In general, the lymphatic vessels.Lymphatic capillariesof the skin travel in loose subcutaneous tissue fol-lowing the superficial veins,however, the deep lym-Lymphatic capillaries are microscopic vessels inphatic vessels of the trunk and viscera travel with thetissue space, and they are anastomoses each other todeep arteries.There are widespread communicatingform networks.Their structures have been revealedbranches between the superficial lymphatic vesselsthat the endothelial cells making up the capillariesand the deep lymphatic vessels. Speed of lymph cir-wall are not tightly joined:their edges loosely over-culation is slow,only as slow as one tenth ofblood inlap each otherand form the opening junctions.Theseveins. In order to maintain the circulation of lymph,arrangement permits fluid to enter easily into the lym-the quantity of lymphatic vessels and their valves arephatic capillariesbut prevents theflow out of the capmany times of these veins.illary much like a one-way valve would operate.Theyare slightly larger and more permeable than blood3.Lymphatic trunkscapillaries (Fig.II-2-2).So lymphatic capillaries arestructurally adapted to ensure the return of proteins toLymphatic trunks are formed by the union of thethe circulation when they leak out of blood capillar-larger lymphatic collecting vessels and named most-ies. Lymphatic capillaries exist throughout the body,ly for the regions from which they collect lymph.except thesplenic pulp,bonemarrow,epidermis,hairThe nine major trunks are the paired lumbar trunks,nails, cornea, lens, cartilages, and the central nervousbrmediastinaltrunk,ubclaviantrunkjuguarsystem.trunks and the single intestinal trunk (Fig, I-2-3).扫描全能王创建
Chapter2LymphaticSystem·239Left jugular trunkRight lymphatic ductLeft subclavian trunkLefbronchomediastinaltrunkThoracicductCisterma chyli一Leftlumbartrunk1Right lumbartrunkIntestinal trunkFig. II-2-3 Lymphatic trunks and ductssurface of lymph nodes through afferent lymphatic4.Lymphatic ductsvessels, and leaves by efferent lymphatic vessels athilus.There arefewer efferent lymphatic vessels thanafferent lymphatic vessels, so the rate of lymph flowLymph is finally delivered to one of two largethrough the nodes is slowed and the diameter of ef-ducts in thoracic and cervical region.These two ductsferent lymphatic vessels is wider than that of afferentare named thoracic duct and right lymphatic duct. De-lymphaticvessels.However,theefferentlymphatictails will be considered in section2 (Fig.II-2-3)vesselsof onelymph nodemaybeafferentlymphaticvessels of the another lymph node.Lymph nodes of-II.LymphNodesten get together and are classed by deep fascia intoLymph nodes are small round or bean-shapedsuperficial group and deep group. Superficial groupsstructures located along lymphatic vessels.In gener-can be easily touched, but deep groups often locatedal, they are grayish pink with length rangefrom 5tonear the hilus of viscera or the branch of blood ves-25mm.Lymphnodes contain slight depressionon onesels in abdomen and pelvis. They are often namedsidecalledhilus wherebloodessels,nerveandffby their location or nearby blood vessels (Fig.IⅢI-2-4)entlymphaticvesselspass.Lymphenterstheconvex扫描全能王创建
240·PARTIⅢIANGIOLOGYCapsuleTrabeculeCortexAfferent lymphaticvesselParacortexzoneCortical sinusLymphaticnoduleArteryNerve-Efferent lymphaticvesselVeinFig.II-2-4 Lymph nodediameter (Fig. II-2-3).This duct begins as dilation,Clinic notescisterna chili,which lies in front of the first lumberIn addition,to act as filter of lymph,lymphvertebra, Cisterna chyli receives intestinal trunk andnodes alsoproduct lymphocytes andplasmocytes,a pair of lumbar trunks. Begins from cistern chyli,and play a role in activatingtheimmunesystem.thoracic duct then passes the aortic hiatus of the dia-Lymph of an organ or region will flowto somephragm behind theaorta and enters theposteriorme-lymphnodeswhichiscalledregional nodesofthisdiastinum in whereit liesbetween vertebral columnorganorregion.Knowledgeofregionalnodesmayand oesophagus.At the level of the fifth thoracic ver-be helpful in diagnosing the site of an infection iftebra it crosses to the left of the vertebral column. Atthere are infected lymph nodes.The location ofthe root of the neck, the duct forms arch of thoraciclymphnodes anddirectionof lymph filowarealsoduct, and enters the left venous angle. At the root ofimportant in the diagnosis and prognosis of cancerthe neck, it also receives subclavian trunk,left jugularwithmetastasis.trunks, left bronchomediastinal trunk.Through thesesix lymphatic trunks, thoracic duct receives lymphSection 2 Lymphaticfrom the left side of the head, neck and chest, theleftupper limb, abdomen, pelvis and two lower limbs,Ductsabout 3/4partsof thewholebody.The principal trunks pass their lymph into twoII .Right Lymphatic Ductlarge ducts,thoracic duct and right lymphatic duct.Each duct empties lymph into venous circulation atRight lymphatic duct is a short duct about I to 1.the venous angle (junction of the internal jugular vein5cm long, and 2mm in diameter. It is united by rightand subclavianvein)on its own side.Thus,lymph isjugular trunk,right subclavian trunk,and right bron-drained back intoblood.chomediastinal trunk.Sometimes the three lymphatictrunks may open separately into right internal jugularI.ThoracicDuctor subclavian veins. Right lymphatic duct receiveslymph from the right side of head, neck,chest, andThoracic duct is the largest lymphatic vessel ofthe right upper limb, about 1/4 of the whole body (Fig.human with about 30 to 40cm in length and 3mm inIⅢI-2-3)扫描全能王创建
Chapter2LymphaticSystem·241Section 3 Lymphnodes,submandibular lymph nodes,submental lymphnodes from posterior to anterior.These lymph nodesNodes and Lymphreceivethe lymph from thehead and face, and thenempty to lateral cervical lymphnodes (Fig.II-2-5)Drainage of Whole Body(1)Occipital lymph nodesI.Lymph Nodes and LymphTheylocate on the surfaceof the insertion of traDrainage of Head and Neckpezius, and receive lymph from occipital portion andnape.1.Lymph nodes and lymph(2) Mastoid lymph nodesdrainage of headThey liebehind ear and on surface of the attachmentofsternocleidomastoid,andreceivelymph fromMost of the lymph nodes of the head are locatedthe parietal, temporal region and retroauricular rein the junction ofhead and neck.They are the occipigion.tal lymph nodes,mastoid lymph nodes,parotid lymphidlymphnodeMastoid lymph.nodeOccipital lymphnodeubmentallvmphnodesSuperficiallaterSubmandibularcervical lymph nodeslymph.nodesFig. II-2-5 The lymph nodes of head and neck(4)Submandibularlymphnodes(3) Parotid lymph nodesThey locate in submandibular triangle near sub-They can beclassed intothe superificial anddeepmandibulargland,receivelymphfrom face,orbitgroups, whichlocate onthe surfaceofparotidglandnasal part, and oral cavity.and intesustanceothegland respectively,andreceive lymphfrom forehead, temple,auricle,extemal(5)Submental lymph nodesybThey lie in submental triangle,receive lymphid gland.扫描全能王创建