Esophageal Diverticula.docx
- 文档编号:29134349
- 上传时间:2023-07-20
- 格式:DOCX
- 页数:13
- 大小:46.24KB
Esophageal Diverticula.docx
《Esophageal Diverticula.docx》由会员分享,可在线阅读,更多相关《Esophageal Diverticula.docx(13页珍藏版)》请在冰豆网上搜索。
EsophagealDiverticula
EsophagealDiverticula
INTRODUCTION
Background:
Adiverticulumisasacorpoucharisingfromatubularorgan,suchastheesophagus.Thisarticlefocusesondiverticulaoftheesophagus.Asiscommonpractice,Zenkerdiverticulum,atypeofdiverticulumthatarisesfromtheposteriorhypopharynx,isalsodiscussedinthisarticle.
Pathophysiology:
Besidesanatomiclocation,severalotherwaystoclassifydiverticulaoftheesophagusandhypopharynxexist.Congenitaldiverticulaarediverticulathatarepresentatbirth,whileacquireddiverticuladeveloplaterinlife.Diverticulaoftheesophagealbodycansometimesbedifficulttoclassifyascongenitaloracquired.
Diverticulaalsomaybeclassifiedonthebasisofhistopathology.Truediverticulacontainalllayersoftheintestinaltractwall.Falsediverticula,alsoknownaspseudodiverticula,occurwhenherniationofmucosaandsubmucosathroughadefectinthemuscularwalloccurs(eg,Zenkerdiverticulum).Aspecialtypeofpseudodiverticula,believedtorepresentdilatedexcretoryductsofesophagealsubmucosalglands,isobservedintheconditionesophagealintramuralpseudodiverticulosis.
Finally,acquireddiverticulaoftheesophagusandhypopharynxalsomaybeclassifiedaccordingtotheirpathogenesisaspulsiondiverticulaortractiondiverticula.PulsiondiverticulaformasaresultofhighintraluminalpressuresagainstweaknessesintheGItractwall.Zenkerdiverticulumoccursduetoincreasedpressureintheoropharynxduringswallowingagainstaclosedupperesophagealsphincter.Anepiphrenicdiverticulumoccursfromincreasedpressureduringesophagealpropulsivecontractionsagainstaclosedloweresophagealsphincter.Incontrast,tractiondiverticulaoccurasaconsequenceofpullingforcesontheoutsideoftheesophagusfromanadjacentinflammatoryprocess(eg,involvementofinflamedmediastinallymphnodesintuberculosisorhistoplasmosis).
Age:
Mostesophagealdiverticulaoccurinmiddle-agedadultsandelderlypeople,althoughpresentationininfantsandchildrenisrarelyseen.Zenkerdiverticulatypicallypresentinpeopleolderthan50yearsandespeciallypresentduringtheseventhandeighthdecadesoflife.
CLINICAL
History:
∙Zenkerdiverticula(seeImages1-2)areformedbytheherniationofmucosathroughanareaofweaknessintheposteriorwallofthehypopharynx(theKilliantriangle).
oSometimesZenkerdiverticulaarecalledpharyngoesophagealdiverticulabecauseoftheircloseproximitytothecervicalesophagus;however,thisissomewhatofamisnomerbecausethediverticulaactuallyarisefromthehypopharynxratherthanfromtheesophagus.
oOfthediverticuladiscussedinthisarticle,Zenkerdiverticulaarethemostcommontypetocausesymptoms.
oZenkerdiverticulaareanacquiredpulsion-typeofdiverticulathatprobablydevelopbecauseoftheagingprocess.Theyformintheposteriorhypopharynxatapointwhereadefectinthemuscularwall,betweentheinferiorpharyngealconstrictormuscleandthecricopharyngealsphincter(Killiantriangle),usuallyexists.
oZenkerdiverticulaarebelievedtooccurbecauseofanoutflowobstructioncausedwhenlossofcoordinationofthebuccalsquirt(ie,swallowingmovementofthetongueposteriorlywithcontractionoftheoropharyngealmuscles)andopeningofthecricopharyngeus(ie,theupperesophagealsphincter)occurs.Thenoncompliantcricopharyngeusmusclebecomesfibroticovertime.
oZenkerdiverticulatypicallypresentinpeopleolderthan50yearsandespeciallypresentduringtheseventhandeighthdecadesoflife.
oOropharyngealdysphagia,usuallytosolidsandtoliquids,isthemostcommonsymptom.Retentionoffoodmaterialandsecretionsinthediverticulum,particularlywhendiverticulaarelarge,canresultinregurgitationofundigestedfood,halitosis,cough,andevenaspirationpneumonia.Thepatientmaynotefoodonthepillowuponawakeninginthemorning.Withverylargediverticula,amassintheneckoccasionallycanbedetected.CancerrarelyhasbeenreportedinassociationwithZenkerdiverticula.
∙Diverticulaoftheesophagealbodyarerelativelyrare.Theyprimarilyoccurinthemiddleanddistalesophagus(seeImage3).
oDiverticulathatoccurinthedistalesophagus,inthelower6-10cm,aretermedepiphrenicdiverticula(seeImage4).
oDiverticulaofthemidanddistalesophagusmayhavevariousetiologies.Forinstance,somediverticulainthemidesophagusarecongenitalinorigin;othersareofthetractionvariety.Withthelatter,diverticuladevelopbytractionfromcontiguousmediastinalinflammationandadenopathy,eg,pulmonarytuberculosisandhistoplasmosis.Thediverticulathatdevelopbytractionandadenopathyusuallyareasymptomatic.
oRetentionofundigestedfoodinlargediverticulaoccasionallyresultsinregurgitation,nocturnalcough,andaspirationpneumonia.
oOccasionalepiphrenicdiverticulaoccurinthesettingoflong-standingpepticesophagitisandstrictures,andtheyrarelyaresymptomatic.OtherrarecausesofdiverticulaofthemidanddistalesophagusincludeiatrogenicsurgicalinjurytotheesophagusandEhlers-Danlossyndrome(weaknessofcollagen).Perhapsthemostcommoncausesofmidesophagealandepiphrenicdiverticulaaremotilitydisordersoftheesophagealbody,includingachalasia,diffuseesophagealspasm,andhypertensiveloweresophagealsphincter.
oDysphagiaisthemostcommonsymptomassociatedwithmidesophagealandepiphrenicdiverticula,althoughitusuallyisrelatedmoretotheunderlyingmotilitydisturbancethantothediverticulumperse.However,onoccasion,thediverticulummayberesponsibleforthedysphagia,particularlyifitisverylargeandfilledwithfoodorabezoar.Regurgitationandaspirationmayberelatedtolargemidesophagealandepiphrenicdiverticula;however,inpatientswithachalasia,regurgitationandaspirationaremorelikelytoberelatedtopooresophagealemptyingfromtheunderlyingmotilitydisturbance(eg,hypertensiveloweresophagealsphincterthatfailstorelax,absenceofesophagealbodyperistalsis).
∙Esophagealintramuralpseudodiverticulosisisaveryrareconditioninwhichnumerous1-to4-mm,saccular,flask-shapedoutpouchingsforminthewalloftheesophagus(seeImages5-6).Pseudodiverticulacannumberfromafewtoahundredormore.Thisconditioncanbesegmentalordiffuse.About200caseshavebeenreportedintheliterature.
oPseudodiverticulaareformedbydilatationoftheesophagealsubmucosalglandsthatcommunicatewiththeesophageallumen.
oEsophagealintraluminalpseudodiverticulosisgenerallyisbelievedtobeanacquiredcondition.Whiletheprecisepathogenesisisuncertain,inflammationandstasisappeartobefactors.Onehypothesisstatesthatblockageofintramuralductsbyinflammatorydebrisresultsindilationofthesubmucosalglands.
oMostpatientswithesophagealintraluminalpseudodiverticulosishaveunderlyingesophagealstricturesordysmotilityoftheesophagealbody.Esophagealintraluminalpseudodiverticulosisalsohasbeenreportedasaconsequenceofcorrosiveinjurytotheesophagus,althoughmostpatientshaveassociatedstrictures.
oDysphagiaisthemostcommonsymptomassociatedwithesophagealintramuralpseudodiverticulosis.Inmostcases,esophagealintraluminalpseudodiverticulosisisrelatedtotheassociatedesophagealstrictureordysmotility.
Physical:
∙Findingsonphysicalexaminationoftenarenormalinpatientswithsymptomaticesophagealdiverticula.However,manypatientsrelateahistoryofdysphagia,chestpain,orregurgitation.
∙Althoughthephysicalexaminationfindingsareoftennormal,alargeZenkerdiverticulummaypresentasaneckmassonphysicalexamination.Halitosisalsomaybepresentandissecondarytoaccumulatedfooddebrisormedicineswithinthediverticulum.
∙Signsandsymptomsofaspirationpneumoniamayaccompanythepresenceoflargesymptomaticdiverticula.
Causes:
∙Mostdiverticulaarecausedbyanunderlyingmotilitydisorderoftheesophagus.
∙Structurallesions,includinganoncompliantcricopharyngeusmuscle(ie,Zenkerdiverticulum),incompleteoruncoordinatedrelaxationoftheloweresophagealsphincter,orstrictures,mayplayaroleaswell.
∙Anunderlyinginflammatoryprocesswithinthemediastinumhasbeenassociatedwithmidesophagealdiverticula.
DIFFERENTIALS
Achalasia
EsophagealCancer
EsophagealMotilityDisorders
EsophagealSpasm
EsophagealStricture
GastroesophagealRefluxDisease
ZenkerDiverticulum
WORKUP
LabStudies:
∙Mostlaboratorystudiesarenothelpfulinthediagnosis.(Upperesophagealwebshavebeenassociatedwithirondeficiencyanemia.)
ImagingStudies:
∙RadiographicstudiesorupperGIendoscopydetectsmanyesophagealdiverticulaincidentallybecauseesophagealdiverticulaoftenareasymptomatic.
∙OnstandardchestradiographsandCTscans,largediverticulaoftheesophagusandhypopharynxalsomaymanifestasair-filledand/orfluid-filledstructurescommunicatingwiththeesophagus.
∙Bariumradiography(ie,bariumesophagography,bariumswallow)generallyisthediagnosticprocedureofchoice.Inadditiontobeingexcellentatdefiningthestructuralappearanceofdiverticula,bariumswallowalsomayprovidecluestounderlyingmotilitydisturbancesthatmaybeinvolvedindiverticularformation.However,ifthepatienthasdysphagiaorodynophagiaorhasalarmsymptoms,thenupperendoscopyisindicated.
oBariumswallowisausefulstudyinpatientswhoaresymptomaticandhavemidesophagealandepiphrenicdiverticula.
oDiagnosisofesophagealintramuralpseudodiverticulosisismadebestusingbariumradiography.
oDiagnosisofZenkerdiverticulumismadebestusingbarium
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- Esophageal Diverticula