Chapter4Urinary SystemThe urinary system consists of twokidneys,whichurine temporarily and one urethra, which carries urineproduce urine; two ureters, which convey urine to thefrom the urinary bladder to the outside of the bodyurinary bladder; one urinary bladder,which stores the(Fig. II-4-1) . The female urethra is an urinary duct,Minorrenal calicesMajorrenal calicesLeftkidneyRenal pelvisRight kidneyUreterUrinary bladderSeminal vesicleDuctus deferens-Ampullaductus deferentisProstateEjaculatoryductPenisBulbourethral glandUrethraEpididymisTestisFig. II-4-1 The male urogenital organs158.D扫描全能王创建a
扫描全能王 创建
krtwey121J-mtrocutonrmalo6- uretelChapter4UrinarySystem·159bladdeywhile the imale urethra serves urinary and genitaltremityandan inferiorextremity;twosurfaces,anan-functions.The urinary system functions to excreteterior surface and a posterior surface;two borders,amedial border and a lateral border (Fig.II-4-2).Thethe waste products, such as urea and uric acid,excesssuperiorextremity (upper pole)isbroaderand thinnerwater and some inorganic salts, so as to regulate thethan the inferior extremity (lower pole).The anteriorcomposition of the internal environment of the body,surface is slightly convex and the posterior surfacein terms of water content, osmotic relations and acidis plane and contacts the posterior abdominal wall.base balance. The female urethra is an urinary duct,The lateral border is convex and themedial border iswhile the male urethra serves urinary and genitalconcave.The central part of the medial border of thefunctions.kidney is a notch, called the renal hilum. The renalSection 1.Kidneysvein,renal artery,nerves, lymphatic vessels, and apart of pelvis enter and leave through it. The renal hi-lum leads into a central recess named therenal sinus.I.Features ofKidneysThe structures which pass through the renal hilum areenclosed togetherbythe connectivetissuetoformtherenal pedicle.The right renal pedicle is shorter thanThekidneys are a pair of bean shaped organs.Inthe left one because it is near the inferior vena cava.adult males,each kidney is about 10cm in length,The order of the structures in the renal pedicle from5cminbreadth,4cminanteroposteriorthicknessandsuperior to inferior is the renal artery, renal vein andthe average weight is 134-148g.In adult females, itrenal pelvis and from thefrontbackward, is therenalis a little smaller and lighter than the one in males.vein,renal artery and renal pelvis.Each kidney has two extremities, a superior ex-DiaphragmInferior vena cavaCeliactrunkSuprarenal glandLSuperiormesenterica.ARenal aRightkidneyRenal v.AbdominalaortaRight testicular aQuadratuslumborumInferiormesenterica.Right uretePsoasmajorIliacusCommon iliacaRectumFemoral n.Urinary bladderrlea2Thekidneyand ureterFig.II-4-2and against themuscles of the posterior abdominalII.Location of Kidneyswall. The superior and inferior extremities of the leftkidney are located at the level of the inferior borderThe kidneys lie behind the parietal peritoneum口扫描全能王创建D
扫描全能王 创建
·162PARTSPLANCHNOLOGYTwo or three minor renal calices join to form onemajor renal calyx.Altogether there are 2-3 majorIV.Coverings of Kidneysrenal calices in eachkidney.Finally the major renalcalices converge into the renal pelvis, which is flatThere are three layers of coverings surroundingfunnel-shaped.The renal pelvis becomes narrow ateach kidney from the outside to the inside,called thethe renal hilum,toform a musculartube, the ureter.renal fascia,the adipose capsule and the fbrous cap.sule (Fig. II-4-6)Adipose capsuleofkidneyAnteriorlayerof renal fasciaFibrous capsuleInferior.vena cavParietal peritoneumRenala10th ribRight crus of diap hragmFascia transversalisPsoasmajor1lthribDiaphragm12thribPosterior layer of renal fasciaA.transversesectionParietal peritoneumSuprarenal glandSagittal(longitudinal)section of rightkidneyAnterior layerof renalfasciaPosterior layer of renal fasciaAdiposecapsuleofkidneylliacusIliacfasciaB.sagittal sectionFig.II-4-6 The coverings of kidney扫描全能王创建a
扫描全能王 创建
Chapter4UrinarySystem163Nephroptosis is the downward displacement of thekidney.L.Renal fasciaV.Renal Blood Supply andThe renal fascia which comes from the extraperi-toneal tissue is divided into anterior and posterior lay-RenalSegmenters to enclose the kidneys and suprarenal glands. Theanterior layer of two sides fuses crossing the medianThe renal artery branches off the abdominal aortaplane in front of the inferior vena cava and abdominaland enters the renal sinus of each kidney. Segmentalaorta. Whereas the posterior layer of two sides merg-arteries diverge from the renal artery to form inter-es with the fascia of the quadratus lumborum and thelobar arteries,which ascend within the renal columnpsoas major.Both layers also merge with the connec-toward the renal cortex.Branches from the interlobartive tissue around the renal arteries and veins.Thearteries diverge near the base of each pyramid andtwo layers of the renal fascia fuse with the infradi-arch over the base ofthe pyramids to form the arcuateaphagmatic fascia above the suprarenal gland. Inferi-arteries.Interlobular arteries projectfrom the arcuateorly, the ureters pass through between the two layers.arteries into the cortex, and the afferent arterioles areThe connective trabeculae from the renal fascia crossderived fromtheinterlobulararteriesortheirbranch-es. The renal arteries supply the renal capsule, renalthe adipose capsule and arrive at the fibrous capsuleto fix thekidney.The three overings of kidney, neigh-pelvis and proximal part of the ureter.The capillaries of thekidneys drain the blood intoboring organs,renal vessels,peritoneum and pres-sure in the abdominal cavity play an important rolethe interlobular veins, which drain into the arcuatein maintaining thenormal location of thekidney.Ifveins. Arcuate veins drain into interlobar veins, whichthese supporting structures are abnormal, thekidneyanastomose and converge to form the renal vein.Themaydescendtoanabnormallowlevel.Nephroptosisrenal veins drain into inferior vena cava.is the downward displacement of the kidney.The renal segment is a part of renal tissues whichis supplied by one segmental artery.There are fiverenal segments(Fig.1-4-7):@The superiorsegmentAdipose capsuleoccupies the anteromedial region of the superiorpole; ② The superior anterior segment includes theThe adipose capsule is inside the renal fascia andrest of superior pole and central anterosuperiorre-continues with the adipose tissue within the renalgion; The inferior segment encompasses the wholesinus. Generally there are more adipose tissue alonglowerpole;The inferior anterior segmentoccupiestheborderofthe kidney.Theadipose capsule asthe region between the superior anterior and inferi-a"spring cushion"protects and supports the kid-or segments:Theposterior segment includestheneyswholeposteriorregion among the superior,superioranterior,inferior,and inferior anterior segments.3.Fibrous capsuleVI.TheRenal AnomaliesThe fibrous capsule is a smooth, transparent, fi-(Fig- II-4-8)brous membrane and closely invests the kidney.Nor-mally it is easily stripped from thekidney,but it isTwo kidneys are connected by a transverse bridgedifficult from a diseased kidneyoftherenal tissue,this is called the Horseshoekidney.The connective trabeculae from the renal fasciaBecause the collecting and excretorytubules fail tocross the adipose capsule and arrive at the fibrousjoin and accumulation of urineoccursin theconvocapsule to fix the kidney. The three overings of kid-luted tubules,it causes them to dilate and graduallyney,neighboring organs,renal vessels,peritoneumto form cycts.This is named the Polycystickidneyand pressure in the abdominal cavity play an import-Because theearlypelvicposition of twokidneysmayant role in maintaining the normal location of thepersist, twokidneys may also bekept on the samekidney. If these supporting structures are abnormal,side.This is called the Ectopic kidneythe kidney may descend to an abnormal low level.-3扫描全能王创建
扫描全能王 创建
.164.PARTIISPLANCHNOLOGYSuperior anterior segmentSuperioranteriorsegmentSuperior segmentArtery ofArtery of superiorPosterior segmentanteriorsegmentsuperior segment-Renal artery-Inferior anterior segmentArtery of posterior segmentRenal peivisArteryof inferioranteriorsegmentInferioranterior segmentUreterInferior segmentInferior segmentArtery of inferior segmentArteryof inferior segmentB.posteriorviewA.anteriorviewFig. I1-4-7 The renal segmental arteries and renal segmentsSuprarenal glandSuprarenal glandKidneyPelvicpositionofthekidneyA.horseshoekidneyB. polycystic kidneyChectopic kidneyFig. II-4-8 Renal anomaliesbeginning of the right external iliac artery.The ureterSection 2 Uretersis continuous superiorly with the funnel-shaped re-nal pelvis. A slight constriction may mark the site ofThe ureters (Fig.Il-4-1) are two muscular tubes,transitionThis part runs downwards and slightly me-onefor eachkidney,which convey the urinefromthedially in front of the psoas major and behind the peri-renal pelvis to the urinary bladder.Each measurestoneum. At the superior pelvic aperture, the left ureterfrom20-30cminlength,0.5-0.7cmindiameterandcrosses through theterminal partof theleft commonconsistsof outerfibrous,middlemuscular,and inneriliac artery anteriorly, and the right ureter passes themucous layers.According to the course,each ureter isbeginning of the right external iliac artery anteriorly,divided into three parts.to continue with the pelvic part.I.AbdominalPartII.Pelvic PartThis part is from the junction of the ureter and theThe pelvic part begins from the point where therenal pelvis to the point where the ureter crosses theureter crosses the iliac artery and ends at the wall ofterminal part of the left common iliac artery or thethe urinary bladder. The ureter descends along the口口扫描全能王创建D
扫描全能王 创建