Dr. Ahmed Fathalla Dr. Ahmed Fathalla IbrahimIbrahimDr. Ahmed Fathalla Dr. Ahmed Fathalla IbrahimIbrahim

Dr. Jamila El-Dr. Jamila El-MedanyMedanyDr. Jamila El-Dr. Jamila El-MedanyMedany

OBJECTIVESOBJECTIVESAt the end of the lecture, students should:At the end of the lecture, students should:List the different parts parts of large intestine.List the characteristic features of colon.Describe the anatomy of different parts of different parts of

large intestine large intestine regarding: the surface anatomy, peritoneal covering, relations, arterial & nerve supply.

Parts of Large IntestineParts of Large Intestine

CECUMAPPENDIXASCENDING COLONTRANSVERSE COLONDESCENDING COLONSIGMOID COLON RECTUMANAL CANAL

ABDOMENABDOMEN

PELVISPELVIS

PERINEUMPERINEUM

Abdomen

Pelvis

Perineum

Characteristics of COLONCharacteristics of COLON(NOT FOUND IN RECTUM & ANAL CANAL(NOT FOUND IN RECTUM & ANAL CANAL

1.1. Taeniae coli:Taeniae coli: (3) longitudinal muscle

bands 2.2. Sacculations Sacculations

(Haustra):(Haustra): Because the Taeniae coli

are shorter than large intestine

3. Epiploic Appendices :3. Epiploic Appendices : Short peritoneal folds filled with fat

Peritoneal CoveringPeritoneal Covering

PARTS WITH PARTS WITH MESENTERY:MESENTERY:

1. Transverse colon2. Sigmoid colon3. Appendix4. Cecum RETROPERITONEAL RETROPERITONEAL

PARTS:PARTS:1. Ascending colon2. Descending colon3. Upper 2/3 of

rectum

Peritoneal CoveringPeritoneal Covering

PARTS DEVOID OF PARTS DEVOID OF PERITONEAL PERITONEAL COVERING:COVERING:

1. Lower 1/3 of rectum

2. Anal canal

Rectum

Analcanal

Anterior Relations of (CECUM – Anterior Relations of (CECUM – ASCENDING & DESCENDING COLONS)ASCENDING & DESCENDING COLONS)

Greater omentum

Coils of small intestine

Greater omentum

Coils of small intestine

Anterior abdominal wallAnterior abdominal wall

Posterior Relations (CECUM – ASCENDING Posterior Relations (CECUM – ASCENDING & DESCENDING COLONS)& DESCENDING COLONS)Cecum:Cecum:1.Psoas major2.IliacusAscending colon:Ascending colon:1.Iliacus2.Quadratus lumborum3.Right kidney.Descending colon:Descending colon:1.Left kidney2.Quadratus lumborum3.Iliacus

Quadratus lumborum

COLIC FLEXURES

Hepatic flexure Splenic flexure

Position: higherAngle: more acute

Relations of Transverse ColonRelations of Transverse ColonAnteriorAnterior: : greater omentum, anterior abdominal wallAnteriorAnterior: : greater omentum, anterior abdominal wall

PosteriorPosterior:: 2nd part of duodenum , pancreas & superior mesenteric vessels.

PosteriorPosterior:: 2nd part of duodenum , pancreas & superior mesenteric vessels.

Relations of Transverse ColonRelations of Transverse Colon

Superior:Superior: liver, gall bladder, stomachSuperior:Superior: liver, gall bladder, stomach

Inferior: Inferior: coils of small intestineInferior: Inferior: coils of small intestine

APPENDIXAPPENDIX

• Surface anatomy:Surface anatomy:• the base of appendix is

marked by Mc’Burney’s Mc’Burney’s pointpoint: :

• A point at the junction of lateral 1/3 & medial 2/3 of a line traced from right anterior superior iliac spine to umbilicus

APPENDIXAPPENDIX Opening:Opening: At posteromedial

aspect of cecum, 1 inch below ileo-cecal junction

Positions:Positions:1.Retrocecal :1.Retrocecal :(most

common) 2.Pelvic2.Pelvic3.Subcecal3.Subcecal4.Preilieal4.Preilieal5.Postileal:5.Postileal: least common

(5)

(3)

(1)

(4)

(2)

RECTUMRECTUMBeginning:Beginning: as a continuation of sigmoid colon at level of at level of S3.S3.Termination: Termination: continues as anal canal, one inch one inch below & in front of tip of below & in front of tip of coccyx.coccyx. Its end is dilated to form the rectal ampulla.Length: Length: 13 cm(5 inches)

Relations of Rectum in PelvisRelations of Rectum in PelvisMALE PELVISMALE PELVIS

Anterior:Anterior: seminal vesicles, posterior surfaces of urinary bladder & prostate glandPosterior:Posterior: sacrum, sacral plexus & coccyx

FEMALE PELVISFEMALE PELVISAnterior:Anterior: posterior wall of vaginaPosterior:Posterior: sacrum , sacral plexus & coccyx

RR RR

Relation Between Relation Between Embryological Origin Embryological Origin of GIT& its of GIT& its Arterial SupplyArterial Supply

VENOUS DRAINAGE OF GIT

• The veins of the gut form the tributaries of the portal vein which enters the liver and drains into the portal circulation.

Lymph drainage of GIT• The lymph vessels follow

the arteries.• Ultimately, all the lymph

is collected at the Preaortic lymph nodes (Superior & Inferior mesenteric).

RELATION BETWEEN RELATION BETWEEN EMBRYOLOGICAL ORIGIN & NERVE EMBRYOLOGICAL ORIGIN & NERVE

SUPPLYSUPPLY Origin: Midgut (endoderm) Nerve supply: (Autonomic):• Sympathetic + Vagus Origin: Hindgut (endoderm) Nerve supply: (Autonomic): • Sympathetic + pelvic

splanchnic nerves Origin: Origin: ectoderm (lower 1/3 of ectoderm (lower 1/3 of

anal canal)anal canal) Nerve Supply: Nerve Supply: SomaticSomatic (inferior (inferior

rectal)rectal)

THANK YOUTHANK YOU