ANATOMY

35

--~

Lecturer : Maher Hadidi lecture#: Date :

I

Portal vein

Hepatod•Jodcnal ligament

?iica circularis ----.:I'D!-

Major duodenal papilla:.

Hepetopancreatic ampulla

Pancreatic cluctl

Periton 3um1

I I I I

I

. ..____ --ugarre:.tuf Tr·jil.<:

-, _____ D:1denojejunzl junction '·"'"'- .1~"-lJ.' 1'1! !fr ......,......, -l .......

F<claticn ;, escr, ~ t:tr+ has : _s OWr'l relations tJ ar~;act-:nt st""'J:._·turP-s.

L ____ ----·--·-- ------·----------------------- ----- ------------

-..,

I I

' ·-­-----

T12 t ....---

l

Uncinate process

I _____ _j

•

•

•

•

Duodenum Capital G-shaped tube rv 10 inches long, extending from pyloroduodenal junction to duodenojejunal junction. Surrounds :,ead c.­pancreas. _Location: Epigastric and umbil;cal regions. Retrop~r_itonea I t:xce_ot its_ J ~.t___-3 n d_ja s.t__ i r ch es.

L___ __________ ----

Plica

Major .:lucdena! papilla~~O<:'I

Pancr8at1c duct

Pentoneum·

Sup. rnesPnt 'J /,'

Sc1p. mese 1tr /'>, ___ ·/ "-

IVC -· Aorta

',...._, ~~gnr;~ent of-:-rei~

·., ~ Dudenojejunal junction · . .lejw Jm

Relaticns: e~ch part has ns 0\' r it:~ations ts adja::enl

sr. Jc::u;es

DuodentJm- Parts

[ 4 parts J Fi~2st part:

• Runs upward and backward.

• Cross Ll vertebra. • 2 inch !ong

• 1st inch ~ntraperi~orreai.

~ 2nd inch retroper;toneal

l

I

I I ____ _j

I I

j

------------------------

IVC

F<L sLprarenai ------,

1st pa

2nd para._~

3rd part _______ ~ Rt. ureter_ .6.scend1-n IO---HF-''­

~olon

.__ __ --- ----

_f=sophagus

d13ph~a::'"'<~

-- Sp!een

.Left kidney __ /

____ f>upeiior rnE::se.:

artery and vsi::

__ Descending :-"Jio;--:

4th part

I

I

____________ ~" _j

1 s t p a rt ---------,-

~..,. I t ' t

~.~;·c~nar ro;ns _____ , Accesscry

pancreatic duct

2nd part __ '---1

Ma1n par.creatic duct

M1jor ~apiila

/

Submucosa

Pyloroduodenar junction Pyloric sphincter

_____ Pancreas '

_ ____,_ __ Duodenojejuna I junction

~J Fe;~ u n ~ n1 I Sp,--,,5;1 3rd part

'"'' ~

---------- ·------~--_j

~------------------

Duodenum- Second part

• D'3scending p3rt. • Retropt.::ritonea:. • About 3 inches long . • On right side of L1-L3. • Developed from foregut

and midgut. • Medial structur~s:

• Hei1d of pancreas. • Receive common

bile duct. • Receive pancreatic

ducts.

Acceso.ory oar.cre~tic dt..ct ..

~~::d pa-l Ma;·,

Pyloroduod{:nal jllnction Py!or1c ~r;/ •i:.c·~r

,._

-- ·-----£ .. ---Sup. r.1esent.

, .t.&V

Jrd or:.:.:

l

I

I

I I I

I

I

i

I

L--------------------- -----·- ---·--------·----___ j

Duodertum~~ Third part

• Transverse part.

~' Retroperitoneal. • 3 inches long.

• Cross L3 vert.

IVC _Escpho~J3

Lt crus .:;f

4th part

---·-------- ---·- --_j

------· --I I

I

I I

Duodenum~ Fourth part

• Ascending part.

• Left to L3-L2.

• 2 inches long, proximal inch is retro pe rita n t:a I and distal inch is intra per :tonenl.

' r-\; ,·_·:: JVC .- f:sophagJs

3r:i ;-:e:i. _ .~I •:-£'t'=~-

'- ·---- ---- -·---- ---·----- ------------ -------------- --

Lt .::t .. l5 .Jf

. .. s~.ec"'

Des::enu·11g ::-ole

4th pai·t

3?

--, I I

,-----------------------------

1

Duodenum~ J .. \rteriad supply

L_

• Divides into 2 halves by the entrance of the common bile duct. • Prox. 1/2 c; foregut • Distal 1/2q midgut

~ Arteries: • Proximal 1/2 : Frnm

celiac artery.

• Distal 1h: Fi-om Sup. M 05~ 'l"-e ~;,.. ~ r'"""~ ~y· I , , - C: L I ; \._ 0 -t": I ,

----------------- ------ --------------'

r !

I

DLJOdenttmf"l4 Veins

Porto-syst'=!rnic .1nastom~si~ .. , :-.;~ t·... \

Left gastric V. .

R1ght gastric V

Portal Vein . T:> ~ive· .

?an::reatico- ~­

duoaer.;. veins

::., Porta! vein: f·orm behind neck of panreas by union

Shr,rt . gastric

1·eins

Splenic vein

·. -::t1ght gastro-omema! ·,-e:n

· lniericr mesc:1te1 ic v~·ll

• Sy 2 veinsqto pottal VEin.

--------~

I I

I I

L--- -- -----------------------------·----- ------------------__ _j

-----------------------------,

Small it1testine Part of the midgut: supplied by SMA.

IJ

•

Mobile intraperitoneal tube rv 6m long,

Extending from duodenojejunal junctiort at Lt. side to ileocecal juncti011 at Rt. side. Located around umbilicus.

• .L\:-rchored to posterior abdomina! wall by a fan­sha~ed mes~ntery.

~ Forrr. of (WO ;Jarl~

" ~~r'Jx1mal q Jejunum ' • Distal Q ileum

-------------------I

, __ _j

I

' '

Small intes-ti~e---Pa-rts --~

i I

• Proximal 3/5 . • Red in color .

• Wider in diameter . • ·rhick wall.

.. Scanty fat with in its mesentery

arc 3.jes

I Dr. r:,~he' T. ·:ac;,c:,, L,,ve/Sic" o' Ju1d~c: :·d /

i L--- ----------------- ---------- ____ __j

'

I

,-~·

Iii

Distal 2/5.

Pale in color. Srnaller in d1ameter. ,- ' 1 ; n ' " .- :::..~ 11 Dll I I r I VV u 1,

\I 1 \ 1- , 1 t.:::l r-n U S f- "":\ t-, \' 1...< r - l ,_, I .... I'-

vJithin its ... --c·.,··or:tf-l.r \! ,,1\... .. )\..-.l_ ...... ,.

tvles•::!ntr;~ ~---

',.. F::.t 1

/ \

\

------1

~--- r\:~.e:·~:J:

I i

L _____________ --------- - ---· -- -------------·---- ______________________ _j

ANATDMY

36

Lecturer : Maher Hadidi lecture # : Date :

Large intestine Extending from ileum to anus

(Intraperitoneal) TranSVbrSe colon

Hepati . 3ngle

As~ending j colon-!

I

(Rertoperrtoneal) 1

<:;: ~ c::. ·~ • ,....... j .. (lntraperitonP.al)

Appendi

M~soapoendix

-~ ;pJ<?-nic angle

-Highest point of cofc·n .

Descsndir!g 1 colon I

l iOP(?' -..c.·;(" , ::.-o I) t.• '~ ~>Jt"'·"·l ·-·.;.....-~1

Teniae ccii

Circuiar folas

Appendicis epiploica

\Sigmoid {Intraperitoneal)

-~ -----~--~--- --··---- -------------- -· --------- '--- .. -;.:'.~.<:-:·,;-:·:::!".:""A;-';",..":" ~~?C'.:.Z:b~ •• :;>....:;.~·,~~-.::· :;· ~-;:,:-- .;..-.:;~.;;;.r::;;;4!_""1 7"~ \ . ; · •. ': - ~ · .•

Appendix .. Intraperitoneal blind

tube.

.. Located in the right iliac fossa. 5 Ascending colo

• Has small lumen, contains masses of lymphoid tissue .

• Long in children & short in adults.

~ Has its own mesentery.

Spring 2013 Dr. Maher T. Hadidi, University of Jordan

ileum I ! i

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Appendix=:

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42

Appendix -·--------·A--·-------~------------·-----·-··----- A-•-. _,,- ••• • Has fixed base. :;.;;"~~;"'f"~:-..::..~..:f;'.~-~"'").~~~'f~~-=-~o:::r.:..~!:.:\:.~:-.:::.-f:"" •. ~::.~·,~r-.

• Tip is variable in position.

• Arterial supgJ_y~ Appendicular A. from SMA.·

:< As:ending colon

'l: ;f fixed i~~:-;--~:~~~":'~?':.~~-~.t"~,.~~-~-~~:·!'~'?::~:==-~~?:~: ·_··~- --:_~-.·--·""--::.tl! . ..; ,, ~·

Spnng 2013 Dr. Maher T. H~didi, University of Jordan 43

~: t:

L____ ____________________ ----------'

Liver • The largest gland in

the body . • Weighs about 1.5 Kg

in adults. "'· • Represent about 2°/o

of adult's body weight. Ill Location: In the right

hypochondriac and epigastric regions, may extends into the left hypochondriac reg1on.

Sub~ostai line (l 3)

Li'V~r

Spring 2013 Dr. Maher T. Hadidi, University of Jordan

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(

45

I[~·,.:::~:,_. :::::::-"£~:::::·~:::-c•::·~'C':c:c::-~~s~:::-· =c=·~'"""'"""·:;;·.::.~''"'-.=.~..0'...£-:.""-~::"~',:;..-'-"'~~~~~'~~~~-•'7:"···.•_,· ,-.~~···'-'""'.:-".:~.1

Right lobe Left lobe Diaphragm

--Ligamentum teres

Borders & Surfaces: superior __ _j_ __ ~

[..... -:~

Poste · f / ... Right- l ;vo /

I / ~< '~/,.. 'Inferior

l

Liver- Anterior view

~ T r i a n g u I a r i n s h a p e ~~~:::=-. .'! ::~~~""'"'-"~"':.?.iP".o":''!':'!'.:::·::.x::·.:,·f:~'':!:'' with 3 borders:

~ Superior

II Right

lii Inferior

. . ·~

);> The inferior border

divides liver into 2

rna j or surfaces :

111 Diaphragmatic.

Jlj Visceral.

Right lobe

~~~":-~""'-"'·~··•J.;..-..;.,-i-k~~

::;pring 2() 13 Dr. Maher T. Hadidi, University of Jordan

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Diaphragm I , .

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47

-- ----'--"---'----'--

Liver- Lateral view

Diaphragmatic

surface:

Convex, Parietal. ,, Visceral surface: -

Posterior , ~

;~ Bare

Concave.

L Spciog 20>3

Subphrr-. Jic r&ee..;s

l

Left triangular ligament

Leftlcbe

Lesser omentum Pnrra hcn~tl's Vi l vjJU v

caudate lobe JVC / Bare area

Anterior coronary layer

Posterior coronary layer '·

Right triangular Jig.

uctl

~~~~ ~Gallbladder I

undusj

Ligamentum !ere , ....

•· r .. :7;:.~>~:=.::?~:::.::~~~·~:~:~~:~~ ~,-~~~~~·~=;:~~~~~;~~:::!~~:·~l~·~_::;~:.:.: •: •::: Spring 2013 49

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~.;."'<-{ :i'"' "".~~, • ~ 7?~7";::'"&"-:""$!~X~~~rrt:::,

"• -, ~)~)~~...~· '

---J J ..:....../ ---' :::,) ...1 ~ ~ ~- -· ::._:_:::._:z ____ _::_ _ _:_ __ • -- ~--=-- ' -~--::_;;

··y:':-•2;

l%

1~

An atom ica I lobes:

By falciform ligament.

. ~- ~~=--·::.~-;-:::.~· --- ·-- ---·~:-:=.:::-::::;::~:-;:::-

---·----~-- ---~ ·--~-- ~ -----·-·-·- .. :_<,.;.-w.'-':'! ,;:,·.~...;:..·.·., ." .. i.~\."; "'"-;:,;_,,.;.__ ,·.·:$~~ ;-~}"Olo••••;. ,. • .._/

Caudate lobe

• Caudate lobe

• Quadrate lobe

Spring 2013

• The 4 lobes of the liver are defined on ;

,f.

the visceral surface ;f by the letter H. r

• Right limb: formed

Fissure~

Fissure~

Fissure for by 2 fossa.

• Left limb: by 2 fissures.

:~ ligamentum ' ;i

• Cross ·bar:

Porta hepatis.

venosum

Fissure for ligamentum teres

Portal Vein Hepatic Artery

-IVC Porta

hepatis ~B

·~ Q:ic -iu·,~• }·

ll""'"""""'~~~-~-:~'!E!.'?!:f:C..'-'!:.::.:?'E!E':f£"""'·'''7:-~~-,--=J; Spring 2013 Dr. Maher T. Hadidi, University of Jordan ~1

(

(

,-------- ---------

Porta hepatis , __ ." ·-·~··•• ~.~ ·--···-- ---~-,·--·.v---~-~-~-·"·•--· • .--- • •• -..~--· ~--··--- • • Hilun1 of the liver. !~:r~~">'!.·C~~:·;·,.-?."K<~J:.TA"i>,~t-:f'.,'W;'""~::.;."!5-~~.~'f~.1."1~l'li<'~...:.:·~.·,_,;:,;.. -::-h.;' -.;...-'.·/~"""'.e-~~-,.,.~. ~ · .

Caudate lobe

11 Between caudate & quadrate lobes.

.. Contents: .. Hepatic-ducts

• Hepatic artery

• Portal vein • Lymph nodes -. Nerves

:i -I<

'~ Left triangu:a ~~ ligament m !{:

Dr. l''ahe,- T. Hadidi. University of Jordan

IVC area

Gallbladder

52

l

! I

I l: __ :<01_3_ -------____ _j

L'ver- Peritoneum

Covered by peritoneum except at:

1. Bare area.

2. Behind gall bladder.~ \

3. Porta hepatis ..

>· Liver is in direct contact with diaphragm~

Caudate lobe

Falciform bgament !

Spring 2013 Dr. Maher T. Hadidi, University of Jordan

(

)VC Bare area Amenor coror:arf layer

. Poster or coro~ary !aver •

(

I

Liver- Arteries, Veins, Lymph • Hepatic artery_;_

Bring about 30°/o of blood to supply the liver itself.

r~;~zoo~¥~-;,_,-. .-~-i,~..;;:;_~,~fiii:m:::;;~~~e~~;;~~·=:.~~ .. ~ :..:;~:: ~'

• Portal Vein: Bring about 70°/o of blood ·· loaded with products of digestion for filtration.

r Act as checking point between GIT and blood. ; Vel·ns.· ;t • :i

• 2 short, right and left. :~

• Directly into IVC.

• Lymph:

Portal

• About 1f2 of all body lymph :t Majordo'ldenal ;~ Ampulla

• End into celiac lymph :~ nodes then to thoracic t duct. t

li !; i1~

duct

~:~ ~~~~~-;:::~o/.".:::~"'?.'i .. ;'~7·.~~-:~~:z._;::?'?.2·:.-~o:;;~::?::'?~~~~~:--' Spring 2013 Dr. Maher T. Hadidi, University of Jordan

---------------

; ' r ~;

•·. ·_..,--.,.J'"X"-' ,.~--<· .?·: - . . ....

I i

I j

I I I !

l

Gallbladder •

•

Pear-shaped sac sheltered at the visceral surface of the right lobe of the liver. Capacity about 30m!.

• Store and concentrate bile about 10 times.

= Parts: • Fundus • Body • Neck • Cystic duct

~ t

Body

Fundus·

'~ Major duodena "' papilla

<~. ', ~

Spring 2013 Dr. Maher T_ Hadidi, University of Jordan

Left hepatic duct

-Common hepatic duct

1st part of --duodenum

',-~ . ---"i--- __.."

in pancreat:c duct

3rd part of

55

(

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I I Gallbladder

Peritoneum • Fundus:

• Intra peritonea I. • Projects beyond

inferior border of

Right hepatic. duct

liver. ·' Body_ i~

, Located below the il tip of the Right 9thlf Fundus costal cartilage. ~~

·~

• Body and neck: :i ·- • R~troperitoneal. ~~. Major duoden

1, papilla

• f~~~o~~~~ ~/~~r~ ~~ r;

Common hepatic duct

i st part of -·-duodenum

__ accessory pancr duct

1111'ain pancreat1c ' duct

?rd part of -.duodenum

;_~~~~~:::!.. :_:_:::~.:_l!!.'"~: ::-:~:::·~::T~-?~::·:.~::-}-:~~~~·.:~?-::::""~~::~,·-- .. -

Spring 2013 Dr. Maher T. Hadidi, University of Jordan

Ga·llbladder

• Common hepatic duct: • About 4cm long.

• Union of right and left hepatic ducts.

• Cystic duct: • s-shaped, about

4cm .long. • Within porta.

hepatis.

r:;:::;·~~~,,~:~::::~:::;""i~#7ii~~~;;:· ;t ',

~~ -Common hePalic duct ~. ;s

1st part of ,,_,,-;-c_,.,.--------duodenum

'--. --·;

3rd part of ~.

• Common bile duct: :~ -duodenum '·

Spring 20 13 .. Dr. Maher T. Hadidi, University of Jordan 57

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Common bile duct • About 8 em long.

• Form by union of common hepatic duct vvith cystic duct.

• Opens in the 2nd P?rt of duodenum at major duodenal papilla, theE$ narrowest part of ducts~ (stone impaction site).

~~~;,;.;:.:;.;::;u::;::.;:;;~:-~~-:;.~~·'7~~~~~::-,.;~'t"':'~·~·--;;.m;;:._:;:.,.,-:..~--;~.:~r:: __ .,;,;;~:,:

ij Right hepatic Left hepatic duct l~

!t Common hepatic duct

j

1st part of --·---duodenum

:;· ~--accessory

pancr. duct

Main pancreatic · duct

;,·

3rd part of t;

-duodenun'

lf;......,;,.:::':"'-"~=~'"'O"~:C:~."2""C:~~::'~~'.·?':"":~·.·~~-: ·-;·~"'""""'"''~ •

Spring 2013 Dr. Maher T. Hadidi, University of Jordan 58

(

( \

ANATOMY

37

----

Lecturer : Maher Hadidi lecture# : Date :

Esophageal branches Common hepatic A.

Diaphragm (Below its right dome) Proper hepatic

Left hepatic A. Left gastric artery

Right hepatic A Shor' gastric As.

Ga~;,roduodenal />..

Speni.._ artery

Celiac artery _ ____/ 11th Rib

~ ·-·· ···--·--. - ---··· ·----• ·,-· < -...,.-,- > ""- • • < ~~ ~..--~. !-.0:;.1'-- .,.- ·- .• ~::;- ->' •• ':: .0<,· ,_ ". ' ~- .".,.-.,"~ • "; ..... _. :•· '1~-~¥; ·""""~·· ;;'.T'.\"".ir.:::o;~."%'".:"-.".···r.t.::-7--;:,-;; ... '!t".V'.-.."l",<'<::•Y'" '· ;. .·;,:·::"·""

. f

Spring 2013 Dr. Maher T. Hadidi, University of Jordan 6C

Spleen • The largest lymphoid

gland in the body.

• Located below the r-ight dome of the diaphragm.

a Its axis is along the Left 10th rib.

R1ght hepatic

Gastroduodenal A,

• Completely _ RightgastncA

intraperitoneal except~~ lts hilurn. ~:

Esophageal branches Common hepatic A. ,

,Diaphragm ' (Below 11~ righ: oome)

Left gasmc artery

Spleen

9th Rib

Oth Kib

11th Rib

Dr. i"laher T. HadiJI, University of ;::>rdar,

Spleen- Parts

2 poles: • Upper pole. • Lower pole.

2 surfaces: • Diaphragmatic

• Convex • Par-ietal

• Visceral • Concave

2 borders: . • Superior ~otched. ~' • Inferior c.=) smooth &

rounded.

Upper pole

Inferior oorder

Splenic vessel

Visceral surface

Spnng 2013 Dr. Ma.,E r T_ Hadidi, University of Jordan

Diaphragmatic suriace I !

_j

c:uporin~ hnro'Clr .; v \JI ,J! ~~V. Vt .- '

(f~mcheci;

Lower pole

62

r s pI ee n- Arterial supply

By splenic artery from celiac artery.

; ..

Ao:

r

Socmg 2013

Aorta

Celiac Trunk Common hep

Gastroduodenal

Superior pancreaticoduodenal

lenic Artery

~_.,lnf pancreatico­duodenal A.

Dr. Maher T. Hadidi, University of Jordan 63

Spleen- venous drainage By splenic vein to portal vein

;;..~.·::-'..~;;;·~~-'" ·: ;,A..;;;-..;,;~~·.:;~~,;,;;.:-'_,.;;;~'*'":;;~--;.:~~~·,~~~v...::~~~~~~~::;m.·;r.:;:~;;,;:;;.::, -~ .. :~n.~~~;~;.~:;;A _i, ':,":.<. .• • . With systemic veins of middle 1/3

Porto-systemic anastomosis

Left gastric V. ,

Right gastric V \

Portal Vein_~o Liver'

Pancreatico- -<: -duodenal veins

• .., Portal vein: Form behind neck vf panreas by union of SMV with Splenic V.

Superior rr.esenteric V

Short gastric veins

'"- Left g2stro-cmental V

-,,-,,Splenic vein

---, Right gastro-omental vein

nferior me~enteric vein

S;>ring 2013 Dr. Maher T. Haciidi, u ... versit'l of Jordan 64

~r;:~~~~~"'-~~-~~~~~~-:.:::~:~~~~~~~~':~:!~·:-!:":~;·~:"'~','_, .. ,-_,_k"0.·····-~--~:-:-:~·;

'· ,, Common bile duct

{ Accessory pancreatic duct

-.· ~·

Minor doudenaL--­papilla

Major doudenal papilla

. I Hepatopancreat1c duct

H9ad of ;.>~ncreas . . . . ..

' - _.,.._, '"'.~ .., •. , _ _.lf ,.~~-~~ ...... .,~~''""» -"'" ,;;:,n-"t'.A:.,...~"?". ~- ~-"'!0-.<:. :<---~:.-..,«.-..:-"'~ .~. : ~-~.;>- ~ ··• -_;.;..,- ... , . .•• :"·• .>;;.'C>l:.:. ""!.~. ·; ··:·:.

Dr. Maher T. nadidi. L'n;Jers1ty of J0rdar.

am pancreatic duct

·37

Pancreas • A complex retroperitoneal

Endocrine and Exocrine gland.

= Located in the hypogastric and left hypochondriac reg1ons.

• About 15 em long. a Comma-shaped extending

from the 2nd part of duodenum to hilum of the spleen.

• Obliquely crossing midline ~· to reach the spleen. ~

t: ~'

Major doudenal papilla

Hepatopancreatic duct' Head of pancre3s

lL ... :.3:i:i~;,.._,:v .• , .,:·.~A;.•<: .. ~Y.e·,~-,.;.:::~.:; ... ::.~ .... >:~ ... :;_.:::.>.,< ~~·:....;·; ._ .;.;.~,_' ·,,;·,;;. ~

Spring 2013 Dr. Maher T. Hadidi, University o: Jordan 68

Pancreas- Parts

• Head: Embraced by duodenum.

!! Neck: Portal vein forms behind it.

• Body: Longest part. EM Tail: Reach hilum of

the spleen. • Ducts: Exocrine

secretion convey to 2nd part of duodenum via two ducts: • Main duct. ~~ Accessory duct.

· Common bile duct

' Accessory panc;eatic duct

Minor doudena/ papilla

MaJor doudenai_ papilla

Hepatopancreatic duct

5"nng 2C13 Dr. Mah~r T. Hadid1, Univ•:cs1ty of Jordan

Head of pancreas

pa::Ci82i:C

dus:

6S

Liver

Portal vein

Pancreas -----

IVC-----o:11

SPLEEN

\\ · .. · Splenic vein

·. \~:L __ inf. mesenteric V.

Form behind neck of pancreas by union of splenic vein and SMV.

ANATOMY

38

if-} \0

--

Lecturer : Maher Hadidi lecture# : Date :

Placenta

Spnng 2.013 Dr. Maher T. Hadidi, University of Jordan 81

1

.. ,, ,,,,, Primary villi Tropho~lastic lacu11oe

. Maternal sinusoid

Connect1ng staik •:• By the beginning of the 3rd week, proliferating cytotrophoblasts invades the syncytiotrophopblasts by forming columns, with cytotrophoblastic core covered by syncytiotrophopblasts

__ Amniotic cavity

called 1 ry chorionic '--' --> vi IIi .

__ 2ry yolk sac

Syncytiotrophoblast ~~~ ecover)

Primary villus (core)

Spnng 2013 Dr. Maher T. Hadidi, University of Jordan 83

• Afterward, the extraembryonic mesodermal cells invade the core of the 1 ry villi to give the 2ry villi that grow toward the decidua, covering the entire q surface of the chorion (with 3 layers).

• By the end of the 3rd week, the core mesodermal cells of the 2ry villi differentiates into blood vessels, forming the villous capillary system. The villi are called 3ry villi (stem villi) with capillary E¢ system.

Syncytiotrophoblast Mesodermal core

Cytotrophoblast

Secondary villus

Villus capillary

Tertiary villus

Spring 2013 Dr. Maher T. Had1di, University of Jordan 84

2

Tertiary stem villi lntervillo space syncytium

Capillaries within mesoderm of chorionic plate and connecting

stalk.

Spnng 2013

Connecting stalk

.._____ _____ Amniotic cavit~

Dr. Maher T. Hadidi, University of Jordan

Maternal artery _____ 2ry yolk sac

85

Development of placenta • Consequently, capillaries in

the 3ry villi contacted with capillaries developing in the extraembryonic mesoderm and in the connecting stalk.

Tertia~ slem villi. lntervillo~s space lyncytiurn

• By the end of the 3rd week, embryonic blood begins to circulate through capillaries of the chorionic villi, establishing a union between intraembryonic circulatory system and placenta before heart beat in the 4th week. Therefore, the villous system is ready to provide the embryo with necessary nutrients and oxygen.

Capillaries wtthtn, mesoderm of i chorionic plate !

i and connecling '_

sta!k

Sprong 2013 Dr. Maher T. Hadid1, University of Jordan

' /

__ Connect1n~ stalK

__ Amniotic cavil1 MJtern21 3rtery

_ 2ry yolk sac

lC

____ Endometrium

86

4

~ Cytotrophoblastic extensions from the chorionic villi spread out overlying the syncytium to reach the maternal endometrium. These chorionic extensions unite to form the outer Cytotrophoblastic shellthatanchorthe stem villi and the chorionic sac to the endometrium.

Tertiary stem villi lntervillo~s space /syncytium I /

Spring 2013

Capillaries within mesoderm of cronon1c plate and connectmg

stalk.

Dr. Maher T. Hadidi, University of Jordan

f.

_Connecl'n~ stalK

Amniotic cavit~ Maternal artery

-:-----J;411L-.. . _ 2ry yolk sac

.·_Endometrium .-·,-

87

~This rapid development increase the surface area of the chorion for the exchange of substances.

Spring 2013

Tertiary stem villi lntervillo~s space Capillaries within

mesoderm of \ chorionic plate

. I and connectmg 1

stalk

:.:;.;._-~:::::~~~h .. ~-..-: .. :~:::-:~·::.r::."P..:_L.._;_··~·" ·-=· ... ,.~~--

..

Syncytillfn

____ Connecting stalk

Amniotic cavity Maternal artery

__ 2ry yolk sac

.... ,~--Endometrium ·'·;/·

Dr. Maher T. Had1di, University of Jordan 88

6

~Placenta is fully developed by the 4th month.

Tertiary stem villi lntervillo~s space Syncytium

Capillaries within mesoderm of I chorionic plate I and connecting !

stalk.

Spnng 2013

Connecting stalk

,,._- ____ Amniotic cavity . Maternal artery

. ____ 2ry yolk sac

Or. Maher T. Hadid1, University of Jordan 89

>- Stem chorionic villi arising from the chorionic plate will enlarge and erode the decidua basalis to enlarge the intervillous space, leaving several decidual septa projecting toward the chorionic plate.

Amniochorionic membrane

p

septum

l Umbilical vei

Decidua basalis

Fetal circulation

omet:rium

Umbilical arteries Decidua parietalis

::~rn~>~::L~ :·.:!;·:.: ~c:

Amnion,'~,--~ J. '-....., . ..., } ·.

'7 '

Anchonng villus

·~--Cytoblasiic ~h2ii

Spnng 2013 Dr. Maher T. Hadidi, University of Jordan 91

1

? Intervillous spaces now, divided by placental septa into freely communicated compartments that located between chorionic plate and decidua basalis. Spiral arteries bring maternal blood to the Intervillous space while endometrial veins drains it.

Spring 2013

Amniotic .. membrane

I

Endometrial veins I

Endometrial spiral arteries

Dr. Maher T. Hadidi, University of Jordan 92

Formation of the placenta

Branches of the stem villi are continuously showered with well­oxygenated maternal blood that circulate through the intervillous space. The free (terminal) villi form the placental membrane barrier separating the fetal and maternal circulation that form the main exchange barrier of material between mother and fetus.

Fetal

circulation Umbilical arteries Umbilical vein_ ''

Amniotic - - • membrane

Dec1dua basalis __ i

_Intervillous space

Endometrial veins Endometrial spiral arteries

Spnng 2013 Or. Maher T. Hadidi, University of Jordan 93

3

Placental membrane barrier

Consists:

1. Syncytiotrophopblasts

2. Cytotrophoblasts

3. CT of villus.

4. Endothelium of fetal capillaries.

Endometrium-

Intervillous-­space

Connecting stalk-

Spnng 2013 Dr. Maher T. Had1di, Un1vers1ty of Jordan

Spiral artery ',.-,

· ·--Chorionic plate

_Chorionic cavity

94