Download PART II • LARYNX • TRACHEA • PHARYNX • ESOPHAGUS

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PARTII
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LARYNX
TRACHEA
PHARYNX
ESOPHAGUS
THELARYNX
THELARYNX-GENERALINFORMATION
•  Larynx:connec%onbetweenthepharynxandthetrachea
•  Preventsforeignbodiesfromenteringtheairways
•  Designedfortheproduc%onofsound(phona%on)
•  Shorterinwomenandchildren
•  Formedby9car%lages:3pairedand3unpaired
•  LocatedinthemidlineoppositetheC3-C6cervicalvertebrae
Thesuperiorborderofthethyroidcar%lage:C3-C4junc<on
Theinferiorendofthelarynx:C6vertebra
THELARYNX
RELATIONSOFTHELARYNX
•Anterolateral-infrahyoidmuscles,platysma
•Lateral-lobesofthethyroidgland,caro%dsheath
•Posterior-itformstheanteriorwallofthelaryngopharynx
•Superior-baseoftongueandvallecula
•Inferior-trachea
Theinfrahyoidmuscles:
•  sternohyoidandomohyoidliesuperficiallyand
•  sternothyroidandthyrohyoidliemoredeeply
Thecaro<dsheath:
•  thecaro<darteriesmedially
•  theIJVlaterally
•  thevagusnerveposteriorly
THELARYNX
ThelarynxissuspendedfromthehyoidboneaboveandaLachedto
thetracheabelowbymembranesandligaments.
Thehyoidbonealsoprovidessupportforthethyrohyoidmembrane.
THELARYNGEALSKELETON
Theskeletalframeworkofthelarynxisformedbyaseriesofcar%lages
interconnectedbyligamentsandfibrousmembranes,andmovedbya
numberofmuscles
THELARYNX
ThereareTHREESINGLECARTILAGES:
•  thyroid
•  epigloOs
•  cricoidcar%lages
andTHREEPAIREDCARTILAGES:
•  arytenoid
•  corniculate
•  cuneiformcar%lages
THELARYNX–THESKELETON
THYROIDCARTILAGE
isthelargestofthelaryngealcar%lages.
ItisformedbyarightandalePlamina,whicharewidelyseparated
posteriorly,butconvergeandjoinanteriorly.
Themostsuperiorpointofthesiteoffusionbetweenthetwobroad
flatlaminaeprojectsforwardasthelaryngealprominence(Adam's
apple).
Theanglebetweenthetwolaminaeismoreacuteinmen(90°)
thaninwomen(120°)sothelaryngealprominenceismoreapparentin
menthanwomen.
Justsuperiortothelaryngealprominence,thesuperiorthyroidnotch
separatesthetwolaminaeastheydivergelaterally.
Thereisalessdis%nctinferiorthyroidnotchinthemidlinealongthe
baseofthethyroidcar%lage.
THELARYNX–THESKELETON
THYROIDCARTILAGE
Theposteriormarginofeachlaminaofthethyroidcar%lageis
elongatedtoformasuperiorhornandaninferiorhorn:
▪Themedialsurfaceoftheinferiorhornhasafacetforar%cula%on
withthecricoidcar<lage.
▪Thesuperiorhornisconnectedbyalateralthyrohyoidligamentto
theposteriorendofthegreaterhornofthehyoidbone.
THELARYNX–THESKELETON
EPIGLOTTIS
TheepigloOsisaleaf-shapedcar%lageaLachedbyitsstemtothe
posterioraspectofthethyroidcar%lageattheangle
projectsposterosuperiorlyfromitsaLachmenttothethyroidcar%lage
TheaLachmentisviathethyro-epigloUcligamentinthemidline
approximatelymidwaybetweenthelaryngealprominenceandthe
inferiorthyroidnotch.
Normally,theepigloOsdivertsfoodandliquidsawayfromthe
laryngealinletandintothelateralfoodchannels.
Itisnotessen%alforrespira%onorphona%on.
THELARYNX–THESKELETON
CRICOIDCARTILAGE
Thecricoidcar%lageisthemostinferiorofthelaryngealcar%lagesand
completelyencirclestheairway
Itisshapedlikeasignetringwithabroadlaminaofcricoidcar<lage
posteriortotheairwayandamuchnarrowerarchofcricoidcar<lage
circlinganteriorly.
Thecricoidcar%lagehastwoar<cularfacetsoneachsidefor
ar%cula%onwithotherlaryngealcar%lages:
▪Onefacetisontheslopingsuperolateralsurfaceofthelaminaand
ar%culateswiththebaseofanarytenoidcar%lage.
▪Theotherfacetisonthelateralsurfaceofthelaminanearitsbase
andisforar%cula%onwiththemedialsurfaceoftheinferiorhornof
thethyroidcar%lage.
THELARYNX–THESKELETON
ARYTENOIDCARTILAGES
Thetwoarytenoidcar%lagesarepyramid-shapedcar%lageswiththree
surfaces,abaseofarytenoidcar<lageandanapexofarytenoid
car<lage
Thebaseisconcaveandar%culateswiththeslopingar%cularfaceton
thesuperolateralsurfaceofthelaminaofcricoidcar%lage.
Theapexar%culateswithacorniculatecar%lage.
Themedialsurfaceofeachcar%lagefacestheother.
THELARYNX–THESKELETON
ARYTENOIDCARTILAGES
Theanterolateralsurfacehastwodepressions,separatedbyaridge,
formuscle(vocalis)andligament(ves%bularligament)aLachment.
ARYTENOIDCARTILAGES
Theanteriorangleofthebaseiselongatedintoavocalprocessto
whichthevocalligamentisaLached.
ARYTENOIDCARTILAGES
Thelateralangleissimilarlyelongatedintoamuscularprocessfor
aLachmentoftheposteriorandlateralcrico-arytenoidmuscles.
THELARYNX–THESKELETON
CORNICULATE
Thecorniculatecar%lagesaretwosmallconicalcar%lageswhosebases
ar%culatewiththeapicesofthearytenoidcar%lages.
Theirapicesprojectposteromediallytowardeachother.
CUNEIFORM
Thesetwosmallclub-shapedcar%lageslieanteriortothecorniculate
car%lagesandaresuspendedinthepartofthefibro-elas<cmembrane
ofthelarynxthataLachesthearytenoidcar%lagestothelateral
marginoftheepigloOs.
THELARYNX–THELIGAMENTS
EXTRINSICLIGAMENTS:
•  Thyrohyoidmembrane
•  Hyo-epigloOcligament
•  Cricotrachealligament
INTRINSICLIGAMENTS:
•  Fibro-elas%cmembraneofthelarynx
•  Cricothyroidligament(cricovocalmembrane,cricothyroid
membrane)
•  Quadrangularmembrane
THELARYNX–THELIGAMENTS
THYROHYOIDMEMBRANE
Thethyrohyoidmembraneisatoughfibro-elas%cligamentthatspans
betweenthesuperiormarginofthethyroidcar%lagebelowandthe
hyoidboneabove.
THYROHYOIDMEMBRANE
Anapertureinthelateralpartofthethyrohyoidmembraneoneach
sideisforthesuperiorlaryngealartery,theinternalbranchofthe
superiorlaryngealnerveandlympha%cs.
Theposteriorbordersofthethyrohyoidmembranearethickenedto
formthelateralthyrohyoidligaments
Themembraneisalsothickenedanteriorlyinthemidlinetoform
themedianthyrohyoidligament
THELARYNX–THELIGAMENTS
HYO-EPIGLOTTICLIGAMENT
Thehyo-epigloUcligamentextendsfromthemidlineoftheepigloOs,
anterosuperiorlytothebodyofthehyoidbone.
CRICOTRACHEALLIGAMENT
Thecricotrachealligamentrunsfromthelowerborderofthecricoid
car%lagetotheadjacentupperborderofthefirsttrachealcar%lage.
THELARYNX–THELIGAMENTS
FIBRO-ELASTICMEMBRANEOFTHELARYNX
Thefibro-elas<cmembraneofthelarynxlinkstogetherthelaryngeal
car%lagesandcompletesthearchitecturalframeworkofthelaryngeal
cavity.
FIBRO-ELASTICMEMBRANEOFTHELARYNX
Itiscomposedoftwoparts:
•  alowercricothyroidligament
•  anupperquadrangularmembrane.
THELARYNX–THELIGAMENTS
CRICOTHYROIDLIGAMENT(CRICOVOCALMEMBRANE,
CRICOTHYROIDMEMBRANE)
ThecricothyroidligamentisaLachedtothearchofcricoidcar%lage
andextendssuperiorlytoendinafreeuppermarginwithinthespace
enclosedbythethyroidcar%lage.
Oneachside,thisupperfreemarginaLaches:
▪anteriorlytothethyroidcar%lage,and
▪posteriorlytothevocalprocessesofthearytenoidcar%lages.
ThefreemarginbetweenthesetwopointsofaLachmentisthickened
toformthevocalligament,whichisunderthevocalfold(truevocal
cord)ofthelarynx.
Thecricothyroidligamentisalsothickenedanteriorlyinthemidlineto
formadis%nctmediancricothyroidligament
THELARYNX–THELIGAMENTS
CRICOTHYROIDLIGAMENT(CRICOVOCALMEMBRANE,
CRICOTHYROIDMEMBRANE)
Themediancricothyroidligamentspansthedistancebetweenthe
archofcricoidcar%lageandtheinferiorthyroidnotchandadjacent
deepsurfaceofthethyroidcar%lageuptotheaLachmentofthevocal
ligaments.
THELARYNX–THELIGAMENTS
QUADRANGULARMEMBRANE
Thequadrangularmembraneoneachsiderunsbetweenthelateral
marginoftheepigloOsandtheanterolateralsurfaceofthearytenoid
car%lageonthesameside.
ItisalsoaLachedtothecorniculatecar%lage,whichar%culateswith
theapexofarytenoidcar%lage.
Eachquadrangularmembranehasafreeuppermargin,betweenthe
topoftheepigloOsandthecorniculatecar%lage,andafreelower
margin.
Thefreelowermarginisthickenedtoformtheves<bularligament
undertheves<bularfold(falsevocalcord)ofthelarynx.
Oneachside,theves%bularligamentofthequadrangularmembraneisseparated
fromthevocalligamentofthecricothyroidligament
belowbyagap.
THELARYNX–THELARYNGEALJOINTS
CRICOTHYROIDJOINTS
Thejointbetweentheinferiorhornsofthethyroidcar%lageandthe
cricoidcar%lageissynovialjoint.
Eachissurroundedbyacapsuleandisreinforcedbyassociated
ligaments.Thecricothyroidjointsenablethethyroidcar%lagetomove
forwardand%ltdownwardonthecricoidcar%lage
Thecricothyroidjointsenablethethyroidcar%lagetomoveforward
and%ltdownwardonthecricoidcar%lage
THELARYNX–THELARYNGEALJOINTS
CRICO-ARYTENOIDJOINTS
Thecrico-arytenoidjointsbetweenar%cularfacetsonthesuperolateral
surfacesofthecricoidcar%lageandthebasesofthearytenoid
car%lagesenablethearytenoidcar%lagestoslideawayortowardeach
otherandtorotatesothatthevocalprocessespivoteithertowardor
awayfromthemidline.Thesemovementsabductandadductthevocal
ligaments.
THELARYNX
CAVITYOFTHELARYNX
Thecentralcavityofthelarynxistubularandlinedbymucosa.
Thesuperiorapertureofthecavity(laryngealinlet)opensintothe
anterioraspectofthepharynxjustbelowandposteriortothetongue:
▪Itsanteriorborderisformedbymucosacoveringthesuperiormargin
oftheepigloOs.
▪Itslateralbordersareformedbymucosalfolds(aryepigloUcfolds),
whichenclosethesuperiormarginsofthequadrangularmembranes
andadjacentsoP%ssues.
▪Itsposteriorborderinthemidlineisformedbyamucosalfoldthat
formsadepression(interarytenoidnotch)betweenthetwo
corniculatetubercles.
THELARYNX
DIVISIONINTOTHREEMAJORREGIONS
Twopairsofmucosalfolds,theves%bularandvocalfolds,which
projectmediallyfromthelateralwallsofthelaryngealcavity,constrict
itanddivideitintothreemajorregions:
•  theves<bule
•  amiddlechamber
•  theinfragloUccavity
▪Theves<buleistheupperchamberofthelaryngealcavitybetween
thelaryngealinletandtheves%bularfolds,whichenclosethe
ves%bularligamentsandassociatedsoP%ssues.
▪Themiddlepartofthelaryngealcavityisverythinandisbetweenthe
ves%bularfoldsaboveandthevocalfoldsbelow.
▪TheinfragloUcspaceisthemostinferiorchamberofthelaryngeal
cavityandisbetweenthevocalfolds(whichenclosethevocal
ligamentsandrelatedsoP%ssues)andtheinferioropeningofthe
larynx.
THELARYNX
Laryngealventricle:
recessesextendinglaterallyfromthemiddlepartofthelaryngeal
cavitybetweenves%bularandvocalfolds.
Laryngealsaccule
Thelaryngealsacculeisablindpocketopeningintoeachventriclethat
islinedwithmucosalglands.Mucussecretedintothesaccules
lubricatesthevocalfolds.
THELARYNX
THERIMAVESTIBULI
Whenviewedfromabovethereisatriangularopening(therima
ves<buli)betweenthetwoadjacentves%bularfoldsattheentranceto
themiddlechamberofthelaryngealcavity.
THERIMAGLOTTIDIS
Inferiortotheves%bularfolds,thevocalfolds(truevocalcords)and
adjacentmucosa-coveredpartsofthearytenoidcar%lagesformthe
lateralwallsofasimilar,butnarrowertriangularopening(therima
gloUdisbetweenthetwoadjacentvocalfolds)
THEGLOTTIS
ThegloUs(thevocalapparatusofthelarynx)makesupthevocalfolds
andprocesses,togetherwiththerimagloOdis,theaperturebetween
thevocalfolds
THELARYNX–THEMUSCLES
THELARYNGEALMUSCLES
Thelaryngealmusclesaredividedinto:
•  Extrinsiclaryngealmuscles
•  Intrinsiclaryngealmuscles
THELARYNX–THEMUSCLES
THELARYNGEALMUSCLES-EXTRINSIC
Extrinsiclaryngealmusclesmovethelarynxasawhole.
Theinfrahyoidmusclesaredepressorsofthehyoidandlarynx,
whereasthesuprahyoidmusclesareelevatorsofthehyoidandlarynx.
Thelarynxiselevatedbythe:
•  thyrohyoid
•  stylohyoid
•  mylohyoid
•  digastric
•  stylopharyngeus
•  palatopharyngeusmuscles
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Thelarynxisdepressedbythe:
omohyoid
sternohyoid
sternothyroidmuscles
THELARYNX–THEMUSCLES
THELARYNGEALMUSCLES-INTRINSIC
Theintrinsicmusclesofthelarynx:
•  adjusttensioninthevocalligaments,
•  openandclosetherimagloOdis,
•  controltheinnerdimensionsoftheves%bule,
•  closetherimaves%buli,and
•  facilitateclosingofthelaryngealinlet.
Allbutoneoftheintrinsicmusclesaresuppliedbytheinferior
laryngealnerve,branchoftherecurrentlaryngealnerve,(CNX).
Thecricothyroidmuscleisinnervatedbythesuperiorlaryngealnerve.
Thecricothyroidissuppliedbytheexternallaryngealnerve,oneofthe
twoterminalbranchesofthesuperiorlaryngealnerve(frominferior
vagalganglionoftheCNX).
THELARYNX–THEMUSCLES
THELARYNGEALMUSCLES-INTRINSIC
Theac%onsoftheintrinsiclaryngealmusclesare:
•  adductorsandabductors,
•  sphincters,
•  tensorsandrelaxers.
Adductorsandabductors:Thesemusclesmovethevocalfoldstoopen
andclosetherimagloOdis.
Theprincipaladductorsarethelateralcrico-arytenoidmuscles,which
pullthemuscularprocessesanteriorly,rota%ngthearytenoidcar%lages
sothattheirvocalprocessesswingmedially.
Theabductorsaretheposteriorcrico-arytenoidmuscles,whichpullthe
muscularprocessesposteriorly,rota%ngthevocalprocesseslaterally
andthuswideningtherimagloOdis.
THELARYNX–THEMUSCLES
THELARYNGEALMUSCLES-INTRINSIC
Sphincters:Thecombinedac%onsofmostofthemusclesofthe
laryngealinletresultinasphinctericac%onthatclosesthelaryngeal
inletasaprotec%vemechanismduringswallowing.
Tensors:Theprincipaltensorsarethecricothyroidmuscles,which%lt
orpulltheprominenceorangleofthethyroidcar%lageanteriorlyand
inferiorlytowardthearchofthecricoidcar%lage.
Relaxers:Theprincipalmusclesinthisgrouparethethyroarytenoid
muscles,whichpullthearytenoidcar%lagesanteriorly,towardthe
thyroidangle(prominence),therebyrelaxingthevocalligamentsto
lowerthepitchofthevoice.
THELARYNX–THEMUSCLES
INNERVATION:THE
RECURRENTLARYNGEAL
NERVE
THELARYNGEALMUSCLES-INTRINSIC
Thevocalismuscleslie:
•  medialtothethyro-arytenoidmuscles
•  lateraltothevocalligamentswithinthevocalfolds.
Thevocalismusclesproduceminuteadjustmentsofthevocal
ligaments,selec%velytensingandrelaxingtheanteriorandposterior
parts,respec%vely,ofthevocalfoldsduringanimatedspeechand
singing.
THELARYNX
ARTERIESOFLARYNX
Thelaryngealarteries,branchesofthesuperiorandinferiorthyroid
arteries,supplythelarynx.
Thesuperiorlaryngealartery(branchofthesuperiorthyroidartery
fromexternalcaro%dartery)accompaniestheinternalbranchofthe
superiorlaryngealnervethroughthethyrohyoidmembraneand
branchestosupplytheinternalsurfaceofthelarynx.
Thecricothyroidartery,asmallbranchofthesuperiorthyroidartery,
suppliesthecricothyroidmuscle.
Theinferiorlaryngealartery(branchoftheinferiorthyroidartery
fromthyrocervicaltrunkofthesubclavianartery)accompaniesthe
inferiorlaryngealnerve(terminalpartoftherecurrentlaryngeal
nerve)andsuppliesthemucousmembraneandmusclesintheinferior
partofthelarynx
THELARYNX
IMA(inferiormiddleartery)THYROIDARTERY
Athyroidimaarteryarisesfromtheaor%carchorbrachiocephalic
arteryandcoursestotheinferiorpor%onoftheisthmusorinferior
thyroidpoles.
Thyroidimaarteryisofsurgicalimportance;itcancause
complica%onssuchasseverebleedinginsurgeryofthethorax,
trachea,thyroidorparathyroidglands.Knowledgeofoccurrenceof
thearteryisespeciallyimportantduringtracheostomyand
thyroidectomy.
THELARYNX
VEINSOFLARYNX
Veinsdrainingthelarynxaccompanythearteries:
▪Superiorlaryngealveinsdrainintosuperiorthyroidveins,whichin
turndrainintotheinternaljugularveins
▪Inferiorlaryngealveinsdrainintoinferiorthyroidveins,whichdrain
intothelePbrachiocephalicvein.
THELARYNX
LYMPHATICSOFLARYNX
Lympha%csdrainregionsaboveandbelowthevocalfolds:
▪Thoseabovethevocalfoldsfollowthesuperiorlaryngealarteryand
terminateinsuperiordeepcervicalnodesassociatedwiththe
bifurca%onofthecommoncaro%dartery.
▪Thosebelowthevocalfoldsdrainintoinferiordeepcervicalnodes
associatedwiththeinferiorthyroidarteryorwithnodesassociated
withthefrontofthecricothyroidligamentoruppertrachea.
ThegloOsisverypoorlyendowedwithlympha%cvessels;some95%of
malignanttumoursconfinedtothegloOswillpresentonlywitha
changeinvoiceorairwayobstruc%on,butwillnotshowsignsofspread
toadjacentlymphnodesatpresenta%on.
THELARYNX
NERVESOFLARYNX
Thenervesofthelarynxare:
•  thesuperiorlaryngealnerveand
•  theinferiorlaryngealnerve
branchesofthevagusnerves(CNX).
Thelarynxisinnervatedby:
•  theinternalandexternalbranchesofthesuperiorlaryngealnerve,
•  therecurrentlaryngealnerveand
•  sympathe<cnerves
THELARYNX
NERVESOFLARYNX
Thesuperiorlaryngealnervearisesfromtheinferiorvagalganglionat
thesuperiorendofthecaro%dtriangle.
Branchesofthesuperiorlaryngealnerve:
•  internal
•  external
laryngealnerves.
Conven%onally,theinternallaryngealnerveisdescribedassensory,
theexternallaryngealnerveasmotor,
andtherecurrentlaryngealnerveasmixed.
THELARYNX
NERVESOFLARYNX
Theinternallaryngealnerve,thelargeroftheterminalbranchesof
thesuperiorlaryngealnerve,piercesthethyrohyoidmembranewith
thesuperiorlaryngealartery,supplyingsensoryfiberstothe
laryngealmucousmembraneofthe
laryngealves%buleandmiddlelaryngealcavity,includingthe
superiorsurfaceofthevocalfolds.
Theexternallaryngealnerve,thesmallerterminalbranchofthe
superiorlaryngealnerve,descendsposteriortothesternothyroid
muscleincompanywiththesuperiorthyroidartery.
Theinferiorlaryngealnerve,thecon%nua%onoftherecurrent
laryngealnerve(abranchofthevagusnerve)entersthelarynxby
passingdeeptotheinferiorborderoftheinferiorpharyngeal
constrictorandmedialtothelaminaofthethyroidcar%lage.
THELARYNX
NERVESOFLARYNX
Becausetheinferiorlaryngealnervesuppliesalltheintrinsicmuscles
exceptthecricothyroid,theinferiorlaryngealnerveistheprimary
motornerveofthelarynx.
Thesuperiorlaryngealnerve(branchoftheinferiorvagalganglion)
innervatesthecricothyroidmuscle,whichtensesthevocalcord,and
innervatesmucosaabovethevocalfold.
Theinferiorlaryngealnerve(branchoftherecurrentlaryngealnerve)
innervatesallofthemusclesofthelarynxexceptforthecricothyroid
andmucosabelowthevocalfold.
AUTONOMICINNERVATIONOFLARYNX
Parasympathe<csecretomotorfibresrunwithboththesuperiorand
therecurrentlaryngealnervestomucousglands.
Postganglionicsympathe<cfibresruntothelarynxwithexternal
caro%dplexus;theyoriginateinthesuperiorandmiddlecervical
ganglia.
THETRACHEA
Thetrachea,extendingfromthelarynxintothethorax,terminates
inferiorlyasitdividesintorightandlePmainbronchi.
Thetrachealcar<lageskeepthetracheapatent;theyaredeficient
posteriorlywherethetracheaisadjacenttotheesophagus.
Theposteriorgapsinthetrachealringsarespannedbytheinvoluntary
trachealismuscle,smoothmuscleconnec%ngtheendsoftherings.
Theposteriorwallofthetracheaisflat
Thetracheaextendsfromtheinferiorendofthelarynxatthelevelof
theC6vertebra.ItendsatthelevelofthesternalangleortheT4–T5
disc.
THETRACHEA
Lateraltothetracheaarethe
commoncaro%darteriesand
thelobesofthethyroidgland.
Thebrachiocephalictrunk
isrelatedtotherightside
ofthetracheaintheroot
oftheneck.
Devia%onofthetracheafromthemidline,apparentsuperficiallyor
radiographically,oPensignalsthepresenceofapathologicalprocess.
THEPHARYNX
Thepharynxisafibromusculartubethatconnectsthenasalcavity,
oralcavity,andlarynx.
Thepharynxissubdividedintothe:
•  nasopharynx
•  oropharynx
•  laryngopharynx
Responsibleforproperlyconduc%ngfoodtotheesophagusandairto
thelungs
Composedof:
•Threeconstrictormuscles
•Threelongitudinalmuscles
•Car%laginouspartofthe
pharyngotympanictube
•SoPpalate
THEPHARYNX
Basedontheseanteriorrela%onshipsthepharynxissubdividedinto
threeregions,thenasopharynx,oropharynx,andlaryngopharynx:
▪Theposteriorapertures(choanae)ofthenasalcavi%esopeninto
thenasopharynx.
▪Theposterioropeningoftheoralcavity(oropharyngealisthmus)
opensintotheoropharynx.
▪Thesuperiorapertureofthelarynx(laryngealinlet)opensinto
thelaryngopharynx.
THEPHARYNX
THENASOPHARYNX–THEBOUNDARIES
•  Roof-fornix
•  Floor-soPpalate
•  Anterior-choanaeofthenasalcavity
•  Posterior-mucosacoveringsuperiorconstrictor
•  Lateral-mucosacoveringsuperiorconstrictor
Os<umoftheauditorytubeopensintothenasopharynx.
Theauditorytubeallowsspreadofinfec%onsbetweenthemiddleear
andthenasopharynx.
Thepharyngealtonsil(adenoid)isonthesuperiorwallofthe
nasopharynx.
THEPHARYNX
THEOROPHARYNX
TheoropharynxliesbetweenthesoPpalateandthe%pofthe
epigloOs.
THEOROPHARYNX–THEBOUNDARIES
•  Superior-nasopharynx
•  Inferior-posterior1/3ofthetongue
•  Anterior-palatoglossalfoldoftheoralcavity
•  Posterior-mucosacoveringthesuperiorandmiddleconstrictor
mm.
•  Lateral-mucosacoveringthesuperiorandmiddleconstrictors
Pala<netonsilsarelocatedintheoropharynxbetweenthe
palatoglossalandpalatopharyngealfolds
EpigloUcvalleculaisthedepressionimmediatelyposteriortotheroot
ofthetongue
THEPHARYNX
THELARYNGOPHARYNX–THEBOUNDARIES
•  Superior-oropharynx
•  Anterior-larynxandepigloOs
•  Posterior-mucosacoveringmiddleandinferiorconstrictormm.
•  Lateral-mucosacoveringmiddleandinferiorconstrictors
Thepiriformfossa(recess)isasmalldepressionlocatedonthelateral
wallofthelaryngopharyngealcavityoneithersideoftheentranceto
thelarynx
Thepiriformfossa(recess)isapoten%alloca%onforobjectsto
becomelodged
Branchesoftheinternallaryngealandrecurrentlaryngealnerveslie
deeptothemucousmembraneofthepiriformfossaandare
vulnerabletoinjurywhenaforeignbodylodgesinthefossa.
THEPHARYNX
THELARYNGOPHARYNX
Anteriorly,itcommunicateswiththelarynxthroughthelaryngealinlet
(aditus).
Thepharynxisseparatedfromtheposteriorlyposi%onedvertebral
columnbyathinretropharyngealspacecontaininglooseconnec%ve
%ssue.
THEPHARYNX
THEMUSCLESOFTHEPHARYNX
Themusclesofthepharynxareorganizedintotwogroupsbasedon
theorienta%onofmusclefibers.
Theconstrictormuscleshavefibersorientedinacirculardirec%on
rela%vetothepharyngealwall,whereasthelongitudinalmuscleshave
fibersorientedver%cally.
THEMUSCLESOFTHEPHARYNX:
•  theconstrictormuscles
•  thelongitudinalmuscles
THEPHARYNX
THECONSTRICTORMUSCLESOFTHEPHARYNX
Theexternalcircularlayerofpharyngealmusclesconsistsofthree
pharyngealconstrictors:
•  superior,
•  middle,
•  inferior.
Posteriorly,theconstrictormusclesfromeachsidearejoinedtogether
bythepharyngealraphe
Anteriorly,thesemusclesaLachtobonesandligamentsrelatedtothe
lateralmarginsofthenasalandoralcavi%esandthelarynx.
Whentheconstrictormusclescontractsequen%allyfromtopto
boLom,asinswallowing,theymoveabolusoffoodthroughthe
pharynxandintotheesophagus.
Alloftheconstrictorsareinnervatedbythepharyngealbranch
ofthevagusnerve[CNX].
THEPHARYNX
THELONGITUDINALMUSCLESOFTHEPHARYNX
Theinternallongitudinalmusclesarenamedaccordingtotheir
origins:
•  palatopharyngeus
•  stylopharyngeus
•  salpingopharyngeus
Thestylopharyngeusfromthestyloidprocessofthetemporalbone
Thesalpingopharyngeus,fromthecar%laginouspartofthe
pharyngotympanictube(salpinxisGreekfor“tube”)
ThepalatopharyngeusfromthesoPpalate(thepalatopharyngeal
archposteriortothepala%netonsil).
THEPHARYNX
THELONGITUDINALMUSCLESOFTHEPHARYNX
•  Stylopharyngeus-glossopharyngealnerve[IX]
•  Salpingopharyngeus-vagusnerve[X]
•  Palatopharyngeus-vagusnerve[X]
Thelongitudinalmuscleselevatethepharyngealwall,orduring
swallowing,pullthepharyngealwallupandoverabolusoffood
beingmovedthroughthepharynxandintotheesophagus.
THEPHARYNX
THEFASCIAOFTHEPHARYNX
Thepharyngealfasciaisseparatedintotwolayers,whichsandwich
thepharyngealmusclesbetweenthem:
▪Athinlayer(buccopharyngealfascia)coatstheoutsideofthe
muscularpartofthewallandisacomponentofthepretracheal
layerofcervicalfascia
▪Amuchthickerlayer(pharyngobasilarfascia)linestheinner
surface.
THEPHARYNX
GAPSINTHEPHARYNGEALWALL
Gapsbetweenmusclesofthepharyngealwallprovideimportant
routesformusclesandneurovascular%ssues
GAPSINTHEPHARYNGEALWALL
Oneofthelargestandmostimportantaperturesinthepharyngeal
wallisbetweenthesuperiorandmiddleconstrictormusclesofthe
pharynxandtheposteriorborderofthemylohyoidmuscle,which
formsthefloorofthemouth
Theoropharyngealtriangle
allowsmuscles,nerves,andvesselstopassbetweenregionslateral
tothepharyngealwallandtheoralcavity,par%cularlytothe
tongue.
THEPHARYNX
GAPSINTHEPHARYNGEALWALL
Thegapbetweenthemiddleandinferiorconstrictormusclesallows
theinternallaryngealvesselsandnerveaccesstotheapertureinthe
thyrohyoidmembranetoenterthelarynx.
Therecurrentlaryngealnervesandaccompanyinginferiorlaryngeal
vesselsenterthelarynxposteriortotheinferiorhornofthethyroid
car%lagedeeptotheinferiormarginoftheinferiorconstrictor
muscle.
THEPHARYNX
THECONTENTSOFTHEGAPSINTHEPHARYNGEALWALL
Superiortothesuperiorpharyngealconstrictor:
•  thelevatorvelipala<ni,
•  pharyngotympanictube,and
•  ascendingpala<neartery
passthroughagapbetweenthesuperiorpharyngealconstrictor
andthecranium.Itisherethatthepharyngobasilarfasciablends
withthebuccopharyngealfasciatoform,withthemucous
membrane,thethinwallofthepharyngealrecess.
THEPHARYNX
THECONTENTSOFTHEGAPSINTHEPHARYNGEALWALL
Agapbetweenthesuperiorandmiddlepharyngealconstrictors
formsapassagewaythatallows:
•  thestylopharyngeus,
•  glossopharyngealnerve,and
•  stylohyoidligament
topasstotheinternalaspectofthepharyngealwall
THEPHARYNX
THECONTENTSOFTHEGAPSINTHEPHARYNGEALWALL
Agapbetweenthemiddleandinferiorpharyngealconstrictors
allows:
•  theinternallaryngealnerveand
•  superiorlaryngealarteryandvein
topasstothelarynx.
THEPHARYNX
THECONTENTSOFTHEGAPSINTHEPHARYNGEALWALL
Agapinferiortotheinferiorpharyngealconstrictorallows:
•  therecurrentlaryngealnerveand
•  inferiorlaryngealartery
topasssuperiorlyintothelarynx.
THEPHARYNX
ARTERIES
Bloodsupplytothepharynxisbybranchesoftheexternalcaro%d
artery:
•  ascendingpharyngeal,
•  superiorthyroid,
•  lingual,
•  facial,
•  maxillaryarteries.
VEINS
Venousdrainageofthepharynxisthroughthepharyngealplexuson
theposterioraspectofthepharynx.
Blooddrainsfromheretotheinternaljugularvein.
THEPHARYNX
LYMPHATICS
Lympha%cdrainageistotheretropharyngealanddeepcervicalnodes.
NERVES
Sensoryandmotorinnerva%ontothepharynxoriginatesfromthe
pharyngealplexusontheposterioraspectofthepharyngeal
constrictors.
Thisplexusisformedbypharyngealbranchesofthevagus[X]and
glossopharyngeal[IX]nervesandbypostganglionicsympathe<c
nervefibersfromthesuperiorcervicalganglion.
THEPHARYNX
Thepharyngealplexusisformedby:
▪thepharyngealbranchofthevagusnerve[X],
▪branchesfromtheexternallaryngealnervefromthesuperior
laryngealbranchofthevagusnerve[X],and
▪pharyngealbranchesoftheglossopharyngealnerve[IX].
Motorfibersintheplexusarederivedfromthecranialpartofthe
accessorynerve[XI],whichrunswiththevagusnerve[X]andsupplies
allmusclesofthepharynx,larynx,andsoPpalateexceptforthe
tensorvelipala%niandstylopharyngeusmuscles,whichare
innervatedbythetrigeminal[V]andglossopharyngeal[IX]nerves,
respec%vely.
THEPHARYNX
NERVES
Sensoryinnerva<onofthepharynxisfromtheglossopharyngeal
nerve[IX].
Themaxillary[V2]andvagus[X]nervesalsocarrysensa%onfroma
smallpartofthepharynx.
THEPHARYNX
SENSORYINNERVATIONOFTHEPHARYNX
Eachsubdivisionofthepharynxhasadifferentsensoryinnerva%on:
▪Thenasopharynxisinnervatedbyapharyngealbranchofthe
maxillarynerve[V2]thatoriginatesinthepterygopala%nefossaand
passesthroughthepalatovaginalcanalinthesphenoidbonetoreach
theroofofthepharynx.
▪Theoropharynxisinnervatedbytheglossopharyngealnerve[IX]via
thepharyngealplexus.
▪Thelaryngopharynxisinnervatedbythevagusnerve[X]viathe
internalbranchofthesuperiorlaryngealartery.
THEESOPHAGUS
Theesophagusisamusculartubethatconnectsthepharynx
tothestomach.Itbeginsintheneckwhereitiscon%nuous
withthelaryngopharynxatthepharyngo-esophagealjunc<on.
Theesophagusconsistsofstriated(voluntary)muscleinitsupper
third,smooth(involuntary)muscleinitslowerthird,andamixtureof
striatedandsmoothmuscleinbetween.
Ontherightoftheesophagusistherightlobeofthethyroidglandand
therightcaro%dsheathanditscontents.
Therecurrentlaryngealnerveslieinornearthetracheo-esophageal
groovesbetweenthetracheaandtheesophagus
Thecervicalpartoftheesophagusissuppliedbythebranchesofthe
inferiorthyroidarteries.
THEESOPHAGUS
Thecervicalesophagusreceives:
•  soma<cfibersviabranchesfromtherecurrentlaryngealnerves
•  vasomotorfibersfromthecervicalsympathe%ctrunksthroughthe
plexusaroundtheinferiorthyroidartery
Themotorfibersofthephrenicnervesupplythediaphragm
THELYMPHATICOFTHENECK
Mostsuperficial%ssuesintheneckaredrainedbylympha%cvessels
thatenterthesuperficialcervicallymphnodes,whicharelocated
alongthecourseoftheEJV.
Lymphfromthesenodes,likelymphfromalloftheheadandneck,
drainsintoinferiordeepcervicallymphnodes.
Mostlymphfromthesixtoeightlymphnodesthendrainsintothe
supraclaviculargroupofnodes,whichaccompanythecervicodorsal
trunk.
ThemaingroupofdeepcervicalnodesformsachainalongtheIJV,
mostlyundercoveroftheSCM
THELYMPHATICOFTHENECK
Efferentlympha%cvesselsfromthedeepcervicalnodesjointoform
thejugularlympha<ctrunks,whichusuallyjointhethoracicduct
Thethoracicductpassessuperiorlythroughthesuperiorthoracic
aperturealongthelePborderoftheesophagus.
Itarcheslaterallyintherootoftheneck,posteriortothecaro%d
sheathandanteriortothesympathe%ctrunkandvertebraland
subclavianarteries
Thethoracicductentersthelebbrachiocephalicveinatthejunc%on
ofthesubclavianandIJVs(lebvenousangle).