Anatomy of Prostate

ANATOMY'OF'PROSTATE' ' ' DEVELOPMENT:'' PROSTATE gland: Endodermal*outgrowth*of*the*prostatic*urethra.*   It$ is$ an$ accessory gland of$ male reproductive Stroma*and*smooth*muscle*from*the*smooth*muscle*around.* * system,$which$surrounds$the$prostatic urethra.$ • Accessory*male*reproductive*organ.* 1.  Site:! • Contributes*to*30%*seminal*fluid.*   It$lies$in$the$lower part of$the$lesser pelvis behind$the$ ' inferior$border$of$the$symphysis pubis, in$front$of$the$ SITE:' rectum$&$below$neck$of$the$bladder.$ • Lower*part*of*lesser*pelvis*behind*inferior*border*of*symphysis*pubis,*in*front*of* rectum*and*below*neck*of*bladder.'   It$ contributes$ to$ • ' 3 0 %$ o f $ t h e$ ' seminal fluid.! DIMENSIONS:' • AP:*2cm* • Vertical:*3cm* SP$ • Transverse:*4cm* R$ • 2cmx3cmx4cm* ' CAPSULES:' • INNER'True'capsule:*fibroImuscular* structure.' • OUTER'False'capsule*(prostatic*sheath):* condensed*visceral*pelvic*fascia.* • Between*these*two*capsules*lies*the*prostatic*venous*plexus.* * * *pierced*by*2* ejaculatory*ducts.' * ! FASCIA'OF'DENONVILLIERS:'   The$ prostate$ is$ easily$ palpated$ by$ a$ finger$ in$ the$ • rectum.$ retro% &pubic% space% of% Retzius$ &$ prostatic$venous$plexus.'&'RELATIONS:' pubo -prostatic ligaments.$ .$ Apex:*inferiorly.' • Posterior*surface*I**flat*and*related*to*ampulla*of*rectum*and*separted*from*it*by* rectoIvesical*pouch*(fascia*of*Denonvilliers).*retroI*pubic* space*of*Retzius*and*prostaticvenous*plexus.' • 2*Rt.*And*Lt.*Near*its*upper*border.  It$ is$ convex and$ lies$ behind$ the$ lower part of$ the$ symphysis pubis.$ –  The$autonomic innervation to$the$corpora$of$the$ penis$ are$ running$ close$ to$ the$ posterolateral$ aspect$of$the$prostatic capsule.*connected*to*pubic*bodies*by*puboI prostatic*ligaments.'DESCRIPTIONS.$ nodes).*inferoIlateral*surfaces*–*convex*and*related*to*levator*ani*(levator* prostate).$$ DRE • • ' ' ' ' ' Fascia&of&Denonvilliers! Prostatic*sheath*(red)*touches*fascia*of*Denonvilliers*(orange).' The*autonomic*innervation*of*the*corpora*of*penis*runs*close*to*posteroIlateral* "  The$recto -vesical fascia is$attached$above$to$the$floor$of$ aspect*of*the*prostatic*capsule*"*at*risk*for*damage*in*radical*prostatectomy* surgery*(removal*of*prostate*with*both*capsules*of*prostate*along*with*the*lymph* recto -vesical pouch and$below$to$the$perineal body.*–*rests*on*superior* fascia*of*urogenital*diaphragm*(roof*of*deep*perineal*pouch)' • Base:*superiorly*(below*neck*of*bladder)*–*contains*part*of*prostatic*venous* plexus.' –  The$prostatic sheath is$touching$with$the$fascia$of$ Denonvilliers.' • Anterior*surface*–*lies*behind*lower*part*of*the*symphysis*pubis.$$   Its$ upper$ part$ is$ connected$ to$ the$ pubic bodies by$ SHAPE. ' . (Benign prostatic • urethra Posterior:*rectum* • hyperplasia Inferior:*its*apex*is*rested*on*deep*perineal*pouch*(superficial*fascia*of*urogenital* (BPH) diaphragm)* When enlarged it produce uvula vesicae (elevated • Superior:*its*base*is*related*to*neck*of*bladder. Anterior: in front of prostatic urethra (fibro-muscular) dysfunction/!impotence!during! transurethral*prostatectomy* 2.*produces*UVULAE'VESICAE'(elevated'mucosa'of' lower'trigone)'"'obstruction'to'flow'of'urine.$ –  The$neural$bundle$is$located$posterior$to$the$prostate. (cancer) RELATIONS'OF'PROSTATE:' 4.*BELOW*ejaculatory*ducts*(pic*3)*"* CANCER. lateral lobes: lateral to urethra.' • Located*anterior*to*prostatic* capsule.$ The*neural*bundle*(star*in* diagram)*located*posterior*to* prostate.!' b.*fascia*of*Denonvilliers* posteriorly. Rt.' 3.*levator*fascia* Inferiorly. Lobes: 5 • "!common!cause!of!erectile! 1. LOBES'OF'PROSTATE:''5'LOBES'(anatomically)' • * • • • • ' ' ' ' ' ' ' Anterior*lobe*–*front*of*prostatic*urethra*(pic*3).* Posterior*–*behind*prostatic*urethra.$ fascia$ of$ Denonvilliers$ posteriorly$ &$ levator fascia inferiorly.* mucosa of the lower trigone  obstruction to flow of * urine. And Lt.* Lateral*LOBES*I**lateral*to*urethra*(pic*2).* Middle*–*between*upper*part*of*prostatic*urethra*and*ejaculatory*ducts*"*BPH. • Middle lobe: between the upper part of prostatic Anterior:*symphysis*pubis* and the ejaculatory ducts.$ –  They$ are$ between$ the$ prostatic capsule (pelvic$ fascia)$ anteriorly.* • Laterally:*levator*ani. (done*in*BPH). ' Posterior lobe: lies behind the prostatic urethra.* ! When*enlarged.prostatic$capsules%&$lymph$nodes). but ' below the ejaculatory ducts. ! * * * * * * * * * * \\* * ' ' ' ' ' ' PERIPHERAL'ZONE:'*bulk*of*apical.$$ ZONES'OF'PROSTATE:*used*in*pathology* e$carcinoma.' ! Main'site'for'BPH.' ! 5%'carcinomas.* ! Surrounds*ejaculatory*ducts.' • Middle*rectal' • Internal*pudenal' *' VENOUS'SUPPLY:' • Prostatic*venous*plexus*–*SANTORINI'PLEXUS.** ! 70%*glandular*tissue*of*prostate.*lateral*aspects*of*prostate.*nonIglandular*tissue.* ! 75%'carcinomas*(does*not*undergo*benign*hyperplasia)* CENTRAL'ZONE:'* ! 25%*glandular*tissue.*posterior.' TRANSTIONAL'ZONE:'='MIDDLE'LOBE.  It$contains$70%$$glandular$pros e$ constitutes$ the$ bulk$ of$ apical.' ! Surrounds*urethra*and*above*ejaculatory*ducts.' ' BLOOD'SUPPLY:' • Inferior*vesical*–*anterior*division*of*internal*iliac*artery.' • Present*only*in*front*and*sides*of*the*prostate.' .$ eral aspects$of$the$prostate.$   75%$of$all$prostate$carcinoma.' ! Extends*from*neck*of*bladder*to*external*urethral*sphincter.$ not gn Superior$view$ • • • • This$ zone$ does not u n* d e r g o$ b e n i g n * hyperplasia.' ANTERIOR'ZONE:'='Anterior'lobe' ! Fibromuscular.' • Drains*into*internal*iliac*veins"which*communicates*with*internal*vertebral* venous*plexus*through*lateral*sacral*veins*(valveless).$ ' –  glandular$prostate$gland.* ! 10%'of'carcinomas. ' _____________________________________________________________________' .*L1.3.4*"*SECRETION*(active* gland).* • SYMPATHETIC:*T11.*I*sacral*sympathetic*chain*+*hypogastric*nerves*"* EXPULSION*OF*PROSTATIC*FLUID.' ! Their*numbers*increase*with*age.' LYMPATIC'DRAINAGE:' • • Internal*iliac*#*ParaIaortic*nodes.' #'HISTOLOGY:' • • Numerous*branched*glands*supported*with*a*dense*SM*and*CT*stroma.*preventing*retrograde'ejaculation'(semen*enters* bladder.' PSEUDOZCOLUMNAR'EPITHELIUM'of*varying*height:' ! Contain*apical*secretory*granules.*can*also*be*caused*by*injury*to*nerves*in*retroperitoneal* lymphadenectomy*in*PCa).2.* • Ejaculation'is*controlled*by*the*SYMPATHETIC*NS*#*contraction*of*SM*stroma* of*the*bladder*neck*(sphincter'vesicae)*#*expulsion*of*prostate*content*and* closure*of*bladder*neck.' ! BASAL*CELLS*found*between*columnar*cells*for*regeneration*of*epithelium.* • PARASYMPATHETIC:*pelvic*splanchnic*nerves*–*S2.12.' Also*to*sacral*and*external*iliac*#*paraIaortic*LN.• Responsible'for'spread'of'cancer'to'lumbar'vertebrae'and'cranium.' NERVE'SUPPLY:' • Inferior*hypogastric*(pelvic)*plexus.* • Lateral*to*rectum.' ! Prostatic*concretion*formed*by*condensed*prostatic*secretions.