Small Intestine Flashcards
Extent of small intestine
Pylorus-Ileocecal junction
What plicae circularis/ Valvesd of kerching
Complete/incomplete circles that slow down the contents of intestine for more absorbtion
Where are plicae circularis mostly present
Most in jejunum, decrease progressively and disappear distally
Consist of intestinal mucosa and core of submucosa
Crypts of leihburken
Simple tubular glands open between villi Lie on mucous membrane Upper half had goblet cells lower half has paneth cells They dsecrete digestive enzymes and mucus highly mitotic
Brunners glands
Lie in submucosa
Small compund tubuloacinar
Mostly in Duodenum
What are the two types of Lymphatic follicles in small intestine
Solitary-present throughout
Aggregated (Peyers patches)- Present in lamina propria of ileum [Get ulcerated in typhoid]
Blood supply of jejenum and ileum
Jejunal and ileal branches via Superior mesentric
Vasa recta supplies the muscular coat
Nerve supply of jejenum and ileum
T9-T11
Vagi
> Myenteric plexus of Aurbach
Lymphatics of small intestine are called
Lacteals that drain intro mesentry and aortic nodes
Types of cells present in the small intestine
- Enterocytes-Absorbtive
- Goblet cells- mucus secreting
- Paneth cells-Antimicorbial/phagocytic contain defensins
- M cells- antigen transporting cells
- Enteroendocrine cells- secrete peptides and amines
Whats the coating of microvilli
Glycocalyx- Lactase, maltase, peptidase, enterokinase
Absence of lactase- Lactose intolerance
Epithelium of intestinal mucosa
Simple columnar
Specialized cells present in Muscularis externa of small intestine are?
Intestinal cells of Cajal- Specialized for GI motility
Pacemaker cells
`Duodenum is present at the level
L1-L3 , retroperitoneal
Relations of 1st par of Duodenum
Anteriorly- liver, gallbladder
Posteriorly- Portal vein, bile duct
Superiorly- Epiploic foramen
Inferiorly- Pancreas
Relations of 2nd part
Anteriorly- Liver, transverse colon
Posteriorly- Right kidney, renal vessles, psoas major
Medially- pancreas and bile duct
Laterally-Right colic flexure
Blood supply of 1st part of duodenum
Right gastric, artery of wilke . retroduodenal arteries
Relations of 3rd part
Anteriorly- superior mesentric vessels. mesentry
Posteriorly- Ureter. psoas major, genital vessels, inf vena cava
Superiorly- Uncinate process
Inferiorly- jejenum
Relations of 4th part
Anteriorly- transverse colon and mesocolon, lesser sac
Posteriorly- Left sympathetic chain, gonadal arteries
Right- root of mesentry
Left- left kidney and ureter
Ligament of triez
Fibromuscular band that suspends and supports duodenal flexure
Extends : Right crus of diaphram till duodenal flexure
Stiped fibres- upper part
Elastic fibres- middle part
Plain fibers- lower part
Blood supply of Duodenum
- superior pancreaticoduodenal via celiac trunk - upto the opening
- inferior pancreaticoduodenal artery via superior mesentric- below the opening
Nerve supply of duodenum
sns- T9+ 10th spinal nerve
Most common site for peptic ulcer
1st part
Moat common site of diverticula
Concave border
Stenosis/Obstruction is common in
2nd part
Lymphatics of duodenum drain to
Pancreaiticoduodenal nodes
>Hepatics>Celiac nodes
>Superior mesentric>cisterna chyli
Common site for peptic ulcer
1st part of duodenum
Duodenal ulcer
relieved by meals and reappears on empty stomach
what may become adherent to duodenum in case of ulcer
liver and gallbladder
Duodenal obstruction may be due to
- entry of bile duct
- annular pancreas
- pressure of superior mesentric artery
- contraction of suspensory muscle
- carcinoma
Acute inflammation of Meckles diverticulum produces symptoms resembling
appendicitis
Intestinal obstructuion is due to which type of ulcers
Tuberculer
