Clinically applied GI I

Question 1

from esophagus to rectum the GI tube is composed of how many layers?

Answer 1

4

Question 2

what type of epithelium makes up the esophagus?

Answer 2

stratified squamous keratinized

Question 3

the epithelium lies on top of what layer?

Answer 3

basal lamina

Question 4

the basal lamina lies on what layer?

Answer 4

lamina propria

Question 5

what are the four layers of the GI tract?

Answer 5

1. mucosa
2. submucosa
3. muscularis externa
4. serosa

Question 6

what is the histological makeup of the mucosal epithelium?

Answer 6

proximal and distal - stratified squamous nonkeratinized

rest of the tract is simplu columnar

Question 7

in which sections of the GI tract are there glands in the submucosa?

Answer 7

esophagus and duodenum

Question 8

what layers make up the mucosa?

Answer 8

epithelium, lamina propria, muscularis mucosae

Question 9

what are the enteric nerve plexuses?

Answer 9

submucosal (meissner’s) and myenteric (auerbach’s)

Question 10

the submucosal (meissner’s) plexus carries what fibers?

Answer 10

parasympathetic postganglionic and sympathetic postglanglionic fibers

Question 11

what is the function of the submucosal (meissner’s) plexus?

Answer 11

regulates activity of muscularis mucosae, gland secretion, blood flow

Question 12

the myenteric (auerbach’s) plexus carries what fibers?

Answer 12

parasympathetic postganglionic neurons and sympathetic postganglionic fibers

Question 13

what is the function of the myenteric (auerbach’s) plexus?

Answer 13

regulates activity of muscularis externa

Question 14

what is the z line?

Answer 14

region in esophagus where stratified squamous nonkeratinized epithelium meets stratified columnar

Question 15

what is barrett’s esophagus?

Answer 15

metaplastic simple columnar epithelium with goblet cells and adenocarcinoma

Question 16

what is necessary for the diagnosis of barrett’s esophagus? what stain is used and what component does it stain?

Answer 16

1. presence of goblet cells

2. alcian blue - stains acidic mucosubstances secreted by goblet cells

Question 17

what third of the esophagus will harbor an adenocarcinoma?

Answer 17

distal third

Question 18

what type of cancer would most likely cause hoarseness?

Answer 18

squamous cell carcinoma

Question 19

where are the four esophageal constrictions?

Answer 19

1. UES
2. aortic arch
3. primary bronchus
4. diaphragm

Question 20

men are how many times more likely to have stratified squamous cell carcinoma of the esophagus than women?

Answer 20

4x

Question 21

african americans are how many times more likely to have stratified squamous cell carcinoma of the esophagus?

Answer 21

8x

Question 22

what muscle constitute the inferior pharyngeal constrictor?

Answer 22

cricopharyngeus and thyropharyngeus

Question 23

what muscle makes up the superior portion of the inferior constrictor?

Answer 23

thyropharyngeus

Question 24

what muscle makes up the inferior portion of the inferior constrictor?

Answer 24

cricopharyngeus

Question 25

what is the clinical relevance of the orientation of the cricopharyngeus and thyropharyngeus?

Answer 25

potential site of weakness between transition in fiber orientation - Killian's triangle diverticulum may form perforation

Question 26

where does ligation of inferior thyroid artery occur during a thyroidectomy?

Answer 26

distal to esophageal branch

Question 27

what is the clinical relevance of venous drainage of the esophagus?

Answer 27

portal hypertension with attendant esophageal varices and hematogenous spread of cancer

Question 28

what is the cause of achalasia?

Answer 28

loss of inhibitory neurons secreting NO and VIP that populate the myenteric plexus possibly damage to dorsal motor nucleus of vagus nerve or extraesophageal nerve plexus

Question 29

in which layer of the esophagus does lymph flow most easily? why? what is the clinical significance?

Answer 29

submucosal - longitudinally arrayed channels easier for metastatic spread

Question 30

what is the direction of esophageal lymph flow above and below the bifurcation of the trachea?

Answer 30

above - upward below - downward

Question 31

what is the incisura angularis?

Answer 31

external landmark to assist in indentifying the antrum from the body of the stomach

Question 32

where do the majority of peptic ulcers occur?

Answer 32

in the vicinity of the incisura angularis (lesser curvature near gastric notch)

Question 33

parietal cells are influenced by what other cell type in the stomach?

Answer 33

gastrin producing cells

Question 34

what is zollinger ellison sydrome? where are these tumors usually located?

Answer 34

1. gastrin producing tumor | 2. gastrinoma triangle

Question 35

what are the borders of the gastrinoma triangle? what is within in?

Answer 35

1. junction of cystic duct and common hepatic duct 2. junction of neck and body of pancreas 3. junction of 2nd and 3rd parts of duodenum pancreas, duodenum

Question 36

what are the target cells of a gastrinoma?

Answer 36

parietal cells

Question 37

what is the physical manifestation of gastrinomas in zollinger ellison syndrome?

Answer 37

prominent rugae due to increased parietal cell mass

Question 38

what are the 6 primary arterial feeders to the stomach?

Answer 38

1. right gastric 2. left gastric 3. right gastro-omental 4. left gastro-omental 5. gastroduodenal 6. splenic

Question 39

what should be considered when ligating gastric arteries?

Answer 39

anatomical variation - left hepatic artery arising from left gastric

Question 40

each vagal trunk gives rise to what nerve innervating the stomach?

Answer 40

left and right gastric nerves

Question 41

what are the nerves of Laterjet?

Answer 41

anterior and posterior gastric nerves

Question 42

which nerves are preserved in surgery for refractory PUD?

Answer 42

crows feet nerves supplying pylorus

Question 43

what is the reason for vagotomy of the stomach? what nerves are resected?

Answer 43

denervation regions containing acid secreting parietal cells

Question 44

how may gastric cancer progress to pancreatic duct obstruction?

Answer 44

lymph drainage along greater curvature into those at head of pancreas or, mass effect of tumor growing into pancreas

Question 45

what are the four signature histologic changes of celiac sprue?

Answer 45

arrayed enterocytes villus atrophy crypt hyperplasia inflammation of lamina propria