Session 1

Question 1

Recognise the gastrointestinal tract as an external environment & discuss the implications of this
Describe the overall processes of the GI tract / Outline the broad functions of the various regions of the GI tract LO

Q. Function of the mouth​

Answer 1

A. 1. Port of entry

2. Saliva: - Chemical breakdown (Amylase (secreted by salivary glands) & Lingual lipase (secreted by lingual glands)
   - kill pathogens immune proteins (e.g. IgA, lysozyme, lactoferrin)
   - Mucins help with lubrication – speaking & mastication
   - Bolus formation
3. Physical breakdown

Question 2

Q. Function of the oesophagus

Answer 2

A. 1. Rapid transport of bolus to stomach through thorax
2. UOS
• Prevents air from entering GI tract
3. LOS
• helps prevents reflux into oesophagus

Question 3

Q. Function of the stomach the stomach SITS on phil

Answer 3

A. 1. Physical breakdown - Vigorous contractions of the stomach cause the food to be liquefied(chyme). Necessary before being released into duodenum.

• Two areas based on motility/contractions
  • Upper area creates basal tone (slow/sustained contractions)
  • Lower area has powerful peristaltic contractions that effectively grind food (thicker muscle layer distally – Has additional inner oblique layer of muscle (of the muscularis externa)
  2. Storage facility: – We eat quicker than we can digest
  – Stomach can distend
  • When empty has folds (rugae) – Receptive relaxation
  • So intraluminal pressures don’t rocket
  3. Chemical digestion: • Acid • Pepsin (protein)
  4. Infection control– HCL
  5. To produce chyme
  6. Secrete intrinsic factor(Vit B12)

Question 4

Q. Function of the liver

Answer 4

A. 1. Kill pathogens: Liver (kupffer cells)
Detoxification
Metabolism

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Question 5

Q. Function of the Duodenum

Answer 5

A. 1. Start of small intestine
2. Neutralisation/osmotic stabilisation of chyme
• Brunner glands -> HCO3 rich secretions
3. Digestion wrapping up
• Pancreatic secretions
• Bile

Question 6

Q. Function of duodenum & jejunum

Answer 6

A. 1. Chemical digestion: • Bile • Exocrine pancreas

Question 7

Q. Function of the jejunum/ ileum

​

Answer 7

A. 1. Final digestion
2. Nutrient absorption
• Mainly jejunum
3. Water/electrolyte absorption
• Mainly ileum
4. Bile recirculation
• Ileum
5. B12 absorption
• Terminal ileum
6. Kill pathogens: Peyers patches (immune surveillance)
•Lymphoid follicles
• Submucosa/mucosa
• Mainly in terminal ileum

Question 8

Q. Function of the colon

Answer 8

A. 1. Storage facility: Contents are only evacuated several times a day (mass movements). Acts as temporary storage.

2. Final water absorption
3. Final electrolyte absorption

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Question 9

Q. Function of the rectum/ anus

Answer 9

A. Defaecation

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Question 10

Q. Why is it so easy for pathogens to invade the GI system?

Answer 10

A. Thin epithelia and large surface area

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Question 11

Q. Types of movement in the GI tract

Answer 11

A. Related to different regions
• Peristalsis
• Segmentation
• Haustral shuttling - pacemaker cells. These send signals to the smooth muscle cells on the walls of the large intestine causing them to contract at regular intervals.
• Mass movements - giant migrating contractions, this pattern of motility is like a very intense and prolonged peristaltic contraction which strips an area of large intestine clear of contents.

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Question 12

Q. Muscle amounts in the bowel

Answer 12

A. – Small amounts of skeletal muscle
– Mainly smooth muscle

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Question 13

Q. Structural features to aid absorption

Answer 13

A. – Length of gut
– Folds
– Villi/microvilli

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Question 14

Q. To eliminate the resulting waste
• Mass movement
– Colon as temporary ?
– Rectum normally ?
– what are the two sphincters in the anus?
Whilst haustral shuttling occurs continuously mass movement only occurs ?
This involves a sudden, uniform peristaltic contraction of smooth muscle of the gut which originates at the transverse colon and rapidly moves formed faeces into the rectum, which is normally empty. The result of this is feeling the urge to defecate.

The contraction maybe stimulated by eating. When this occurs it is called ?

Answer 14

A. storage site, empty, Internal/External anal sphincter,
once or twice per day
gastro-colic reflex

Question 15

Answer 15

Question 16

Answer 16

Question 17

Identify the common disease processes affecting each part of the gut, and the ways in which they may present LO

Q. Dysphagia, Acid Reflux, Barrett’s Oesophagus, Oesophageal Varices, Peptic Ulceration, Pancreatitis, Jaundice, Gallstones, Malabsorption, Appendicitis, Peritonitis, Inflammatory Bowel Disease, Acute blockage of small intestines, Haemorrhoids, Prolapse, Diverticula, Meckels’ Diverticulum, Colo-Rectal Cancer

Answer 17

A. Dysphagia – Difficultly swallowing. May be caused by problems with the oesophagus, e.g. musculature, obstruction by tumour or neurological, e.g. a stroke. Tumours of the oesophagus, high up are Squamous Cell Carcinoma, lower down are Adenocarcinomas.

Acid Reflux – Sphincter between the oesophagus and the stomach is weak (LOS), acid refluxes into the oesophagus & causes irritation and pain (heartburn).

​

Question 18

Q. Present ​

Answer 18

A. heartburn, bad breath, chest pain, vomiting, breathing problems, and wearing away of the teeth

Question 19

Q. Complications include

Answer 19

A. esophagitis, esophageal strictures, and Barrett’s esophagus

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Question 20

Q. Risk factors

Answer 20

A. obesity, pregnancy, smoking, hiatus hernia, and taking certain medicines

Barrett’s Oesophagus – Metaplasia of the lower oesophageal squamous epithelium to gastric columnar. This is to protect against acid reflux.

Oesophageal Varices – Portal venous system is overloaded due to cirrhosis, blood is diverted to the
oesophagus through connecting vessels. This leads to the dilation of sub mucosal veins in the lower part of the oesophagus.

Question 21

Q. Esophageal varices are unlikely to cause symptoms unless they have ruptured. When this happens, you may experience:

Answer 21

A. hematemesis (blood in your vomit)

stomach pain
lightheadedness or loss of consciousness
melena (black stools)
bloody stools (in severe cases)
shock (excessively low blood pressure due to blood loss that can lead to multiple organ damage)

Peptic Ulceration – Area of damage to the inner mucosa of the stomach or duodenum, usually due to irritation from gastric acid.

Pancreatitis – Inflamed pancreas, causes considerable pain. Characterised by the release of amylases into the blood stream.

Jaundice – Liver cannot excrete bilirubin, which accumulates in the blood. If build up of bilirubin is due to excess haemoglobin breakdown it is Pre-hepatic Jaundice. If build up of bilirubin is due to bile duct obstruction and back up of bile causing liver damage it is Post-hepatic or Obstructive Jaundice

Gallstones – Precipitation of bile acids and cholesterol in the bladder forms gall stones. Often asymptomatic, but may move within the gall bladder causing painful Biliary Colic, or move to obstruct biliary outflow. Tumours of the pancreas may also obstruct outflow.

Malabsorption – Several conditions affect how well the intestines can absorb things.

Appendicitis – Inflammation of the appendix, presents as a sharp pain in the side at the same level as T10, which then localises to the right lower quadrant.

Peritonitis – Inflammation of the peritoneum.

Inflammatory Bowel Disease – E.g. ulcerative colitis and Crohn’s disease

Acute blockage of small intestines – Present with Pain (in their back), vomiting and bloating.

Haemorrhoids – Vascular structures in the anal canal that aid with stool control. When they become
swollen and inflamed they are painful, itchy and blood may be present in stool.

Prolapse – Literally means to fall out of place. Prolapse is a condition where organs fall down or slip out of place. E.g. the rectum can prolapse.

Diverticula – Pressure is too high in the colon, producing an abnormal out pouching to form a hollow. The sigmoid colon is the area most prone as the blood supply causes an area of weakness (?)

Meckels’ Diverticulum – A pouch in the lower part of the small intestine, a vestigial remnant of the yolk sac. It can produce ectopic gastric mucosa that may then produce gastric acid, causing irritation.

Colo-Rectal Cancer – The large intestine is a common site of malignancies, and colo-rectal cancer is a major cause of mortality.

Question 22

Describe the different endoscopic and laparoscopic tools available to investigate the GI tract LO

Q. Endoscopy allows

Answer 22

A. Visual examination, biopsy sampling & therapeutic treatment of the GI tract

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Question 23

Describe the different endoscopic and laparoscopic tools available to investigate the GI tract LO

Q. Endoscopy allows

Answer 23

A. Visual examination, biopsy sampling & therapeutic treatment of the GI tract

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Question 24

Q. What procedure allows visualisation of the nasopharynx, oropharynx and throat (pharynx and larynx)

​

Answer 24

A. Small caliber nasendoscopes

Question 25

Q. What procedure allows us to view the oesophagus, stomach and duodenum (ZoGD)

Answer 25

A. Upper GI endoscopy ​

Question 26

Q. Endoscopic retrograde cholangiography & pancreatography (ERCP) is performed via duodenoscopy, which allows?

Answer 26

A. Cannulation of the duodenal papilla. Technological advances are allowing clinicians to view the small bowel via capsular endoscopy. The whole of the colon can be examined using colonoscopy ​

Question 27

Q. Nasendoscopy allows visualisation of ?

Answer 27

A. Nose, mouth, pharynx ​

Question 28

Q. OesophagoGastriDuodenoscopy (OGD) 1. How long is the oesophagus? 2. Where does is originate and terminate at? 3. What anatomical structure marks the commencement of the oesophagus 4. Landmarks occasionally visible during OGD are 5. The main landmark visible within the oesophagus is the? 6. What can the endoscope do at this point? 7. Chronic acid exposure in the oesophagus can lead to? 8. Where does the diaphragm cuff the the oesophagus at or below? 9. Why might this relationship be disturbed 10. Where does the upper 2/3rd of the oesophagus receive its blood supply? & where does it drain

Answer 28

A. 1. 25 cm long 2. Origin: inferior border of the cricoid Cartilage Terminate: cardiac orifice of the stomach at the level of the 7th costal Cartilage 3. At endoscopy the cricopharyngeal sphincter 4. Indentation form the left main bronchus (T5) Or Pulsation of the left atrium (T6-7) 5. Has oesophagastric mucousal junction where the pale pink squamous oesophageal mucosa abits the dark red gastric mucosa 6. Can be measured using the endoscope and is usually 38-40 cm from the incisor teeth in the adult patient 7. Reflux oesophagitis -\> metaplasia of lower oesophageal squamous epithelium to gastric columnar epithelium (Barett’s oesophagus) 8. Oesophagogastric mucosal junction 9. Hiatus hernia where a weakness in the oesophageal hiatus allows the cardia and fungus of the stomach to herniate into the thorax. 10. Inferior thyroid artery and the aortic branches Drains directly into the systemic circulation by the inferior thyroid vein and azygous branches

Question 29

11. Where does the lower 1/3 of the oesophagus receive its blood supply from? 12. Oesophageal varicies may occur in patients with? What are varices and why is this? 13. What is dysphasia and odynophagia 14. What is achalasia 15. What is a benign oesophageal stricture? 16. Malignancy in the oesophagus 17. The oropharynx lies behind the ?, & forms the portion of the pharynx below the ? but above the ? It extends from? 18. Because both food and air pass through the ?, a flap of tissue called the ? closes over the glottis to prevent ? 19. The oesophagus is a muscular tube that passes food from the pharynx to the stomach. It is continuous with the lower part of the laryngopharynx. The oesophagus has several layers, from inside to out:

Answer 29

11. Left gastric branch of the celiac trunk and the left inferior phrenic artery. Thus oesophagus has a mixed venous drainage: portal system -\> left gastric vein Systemic circulation -\> =azygous vein creating a PORTO-SYSTEMIC anastomosis. 12. Portal hypertension 13. Dysphagia – The symptom of difficulty in swallowing Odynophagia – The symptom of pain whilst swallowing 14. failure of smooth muscle fibers to relax 15. 16. 17. oral cavity, nasopharynx, laryngopharynx, the uvula, which is the end of the palate, to the level of the hyoid bone 18. oropharynx, epiglottis, aspiration 19. o Mucosa composed of non-keratinized stratified squamous epithelium, lamina propria and a layer of smooth muscle (Muscularis Mucosa) o Submucosa containing the mucous secreting glands o Mucularis externa. Upper third of oesophagus is striated, skeletal muscle under conscious control for swallowing. The lower two thirds are smooth muscle under autonomic control (peristalsis).

Question 30

20. Once food has been masticated and mixed with saliva to form a bolus, it must be swallowed. Swallowing is in three phases:

Answer 30

20. Oral preparatory phase (0-7.4) • Voluntary • Tongue pushes bolus towards pharynx • Once bolus touches pharyngeal wall, pharyngeal phase begins Pharyngeal phase (7.4-7.6) • Involuntary • Soft palate seals off nasopharynx • Pharyngeal constrictors push bolus downwards • Larynx elevates, closing epiglottis • Vocal cords adduct (protecting airway) and breathing temporarily ceases • Opening of the upper oesophageal sphincter Oesophageal phase (7.6 onwards) • Involuntary • Closure of the upper oesophageal sphincter • Peristaltic wave carries bolus downwards into oesophagus o The muscle in the upper third of the oesophagus is voluntary striated muscle under somatic control o The muscle of the lower two thirds is smooth muscle under control of the parasympathetic nervous system. o A wave of peristalsis sweeps down the oesophagus, propelling the bolus to the stomach in ~9 seconds. o Coordinated by extrinsic nerves from the swallowing centre of the brain o Lower oesophageal sphincter opens

Question 31

21. What is oesophageal achalasia 22. Dysphagia may result as a (2) 23. Broadly speaking, dysphagia can be split into two categories 24. The stomach produces strong acids (HCl) and enzymes (pepsin) to aid in the digestion of food. The mucosa of the stomach provides protection from its harmful content, but the mucosa of the oesophagus does not have this protection. The oesophagus is protected from these acids by? 25. The reflux of the stomachs contents into the oesophagus and pharynx causes several symptoms, including a ?

Answer 31

21. an esophageal motility disorder involving the smooth muscle layer of the esophagus and the lower esophageal sphincter (LES).[1] It is characterized by incomplete LES relaxation, increased LES tone, and lack of peristalsis of the esophagus (inability of smooth muscle to move food down the esophagus) in the absence of other explanations like cancer or fibrosis. 22. - consequence of a primary oesophageal disorder, e.g. motility problems of the smooth muscle preventing peristalsis. The name for this condition is achalasia. - secondary consequence of another issue, E.g. obstruction or compression of the oesophagus due to a tumour. 23. o Dysphagia for Solids Oesophageal Dysphagia Investigate with a barium swallow/endoscopy o Dysphagia for liquids Oropharyngeal Dysphagia Investigate with a flexible endoscopy evaluation of swallowing. This will allow you to view the entire trachea/oesophagus. 24. - The lower oesophageal sphincter - angle of His - The crus of the diaphragm helps with the sphincteric action. 25. cough, hoarseness and asthma

Question 32

Q. The stomach is entered as the endoscope passes through the lower oesophageal sphincter, which is a physiological sphincter which helps keep chyme within the stomach & reducing reflux. The other mechanisms aiding this process are: ​

Answer 32

A. o Acute angle of entry of the oesophagus into the stomach produces a valve like effect o The mucosal folds at the oesophagogastric junction act as a valve o The right crus of the diaphragm acts as a ‘pinch cock’ o The positive intra-abdominal pressure compresses the walls of the intra-abdominal oesophagus

Question 33

Q. The stomach is divided into?

Answer 33

A. cardia, fundus, body and pyloric antrum

Question 34

Q. The stomach has a greater and lesser curve. What marks the division between the body and pyloric antrum?

Answer 34

A. The incisura angularis (lies in the lesser curve) ​

Question 35

Q. The lining of the stomach has longitudinal ridges known as ? These gastric folds have vary in size. Q. The pyloric antrum narrows to produce the pyloric canal. What lies distal to this canal and what is its function?

Answer 35

A. Rugae A. At the end of the canal lies the pyloric sphincter (muscular thickening of the distal pylorus), which controls passage of stomach contents in the duodenum

Question 36

Q. Gastric ulceration is commonly benign and is found most commonly on which curvature of the stomach?

Answer 36

A. Lesser curve at the angulus ​

Question 37

Q. When should malignancy be expected?

Answer 37

A. Irregular margins, but early cancers may appear like small benign cancers, thus a biopsy is mandatory at endoscopy. ​

Question 38

Q. 1. What is the first part of the SI called? 2. From its origin at the pyloric sphincter it passes in a C-shape around the head of the pancreas to Form? When? Which is supported by? 3. It commences at the L1 to the right of the midline curving around to the right of the midline at L2/3 and the duodenojejunal flexure. It starts intraperitoneally but becomes a retroperitoneal (what does this mean?) organ along its course. 4. How does the endothelium ( shouldn’t it be epithelium) differ from the stomach epithelium? 5. How many divisions does the duodenum have 6. 1st or superior part is 5cm long and is overlapped by? 7. Clinical significance 8. Where are duodenal ulcers commonly found? 9. State is the outcome if the duodenum has and anterior or posterior ulcer 10. Relationship of second part of the duodenum to the peritoneum?

Answer 38

1. The duodenum 2. The jejunum Duodenojejunal flexure (DJ flexure) Ligament of Treitz 3. It starts intraperitoneally but becomes a retroperitoneal (what does this mean?) organ along its course. 4. Macroscopically the endothelium differs from stomach endothelium, this can be seen on passing through the pylorus (read about coeliac disease) 5. 4 6. The liver and gallbladder 7. Occasionally, gallstones may cause erosion from the gallbladder to the 1st part of the duodenum leading to a choledocoduodenal fistula, which can subsequently give rise to gallstone ileus as the gallstones travel through the small bowel & eventually obstructs the lumen. 8. Duodenal ulcers are commonly located in the 1st part of the duodenum (more common then peptic ulcers) 9. Anterior ulcer may perforate causing peritonitis Posterior ulcer may erode into the gastroduodenal artery (which is closely related to the posterior wall) resulting in massive haemorrhage (WHY IS THIS?) or into the pancreas causing severe pain radiating to the lumbar region. 10. 2nd or descending part is retroperitoneal, 7.5cm long and descends in a curve around the head of the pancreas

Question 39

11. The major duodenal papilla lays half way along the posteromedial aspect of the 2nd part of the duodenum. It signifies the opening of the main pancreatic duct (of Wirsung). The opening at the duodenal papilla is guarded by the ? The accessory pancreatic duct of Santorini open a little above the duodenal papilla. 12. Label the diagram 13. Where does the transition from the embryonic forgut to the midgut occur? 14. 3rd or horizontal part is 10cm long & runs transversely at the level of L2/3 crossing? 15. Ulceration in the 2nd part of the duodenum is less common than the 1st & suggests?

Answer 39

11. sphincter of Oddi, 12. Image 13. At the duodenal papilla. As such the duodenum as a blood supply originating from both the celiac access (foregut) and the superior mesenteric artery (midgut). 14. the aorta below the origin of the superior mesenteric artery. 15. either pancreatic disease or Zollinger-Ellison syndrome (what is this?) (Zollinger-Ellison syndrome is a collection of findings in individuals with gastrinoma, a tumor of the gastrin-producing cells of the pancreas. Unbridled gastrin secretion results in elevated levels of the hormone, and increased hydrochloric acid secretion from parietal cells of the stomach. It can lead to ulceration and scarring of the stomach and intestinal mucosa.)

Question 40

Q. 1. The close relation of the duodenum to the abdominal aorta may lead to the development of a? 2. The duodenum is located between the superior mesenteric artery (anterior) and aorta (posterior). When patient have dramatic weight loss they may develop? 3. State the relationship of the 4th or ascending portion to the peritoneum? 4. Ascends to the ? of the midline to L1 where it turns left to form the ? 5. At this point the jejunum has a mesentery and becomes ? 6. It is thought that contraction of the ligament of Treitz aids ? Why? 7. What marks the duodenojejunal flexure? 8. What is the ligament of Treitz?

Answer 40

A. 1. Aorto-duodenal fistula in patients with disease of the duodenum or aorta. This usually presents as upper GI haemorrhage (this is rare) 2. SMA syndrome where duodenal obstruction (partial or complete) is caused by external compression of the duodenum by the aorta & SMA. 3. retroperitoneal 4. left, duodenojejunal flexure, also known as the DJ flexure 5. intraperitoneal 6. the peristaltic movement of its contents by widening the angle of the flexure. 7. A well-marked duodenal fold, the suspensory ligament of Treitz that, descends from the right crus of the diaphragm marks the duodenojejunal flexure. 8. Is fibrous and anchors the start of the jejunum and in a deceleration injury may lead to a traction injury in the jejunum and subsequent perforation.

Question 41

Q. Endoscopic Retrograde CholangioPancreatography ERCP allows endoscopic and radiological examination of the?

Answer 41

A. biliary tree & pancreatic duct, biopsy sampling and therapeutic procedures to relieve obstructive jaundice. ​

Question 42

Q. The biliary tree is examined in a retrograde fashion by?

Answer 42

A. Cannulating the duodenal papilla, through the sphincter of Oddi into the small widening at the distal end of the common bile duct (Ampulla of Vater). ​

Question 43

Q. The biliary tree commences within the liver from the intrahepatic ducts, which form the? Q. The left and right hepatic ducts then converge to form?where? It is approx. . Cm in length?

Answer 43

A. left & right hepatic ducts A. The common hepatic duct, porta hepatis, 4 cm

Question 44

Q. What duct joins the common hepatic duct? Forming?

Answer 44

A. The cystic duct arising from the gallbladder joins the common hepatic duct Forming the common bile duct. ​

Question 45

Q. State the length of the common bile duct and it’s route into the duodenum

Answer 45

A. 10cm in length and up to 7mm in diameter. - passes behind the duodenum - runs in a groove in the posterior aspect of the head of pancreas or within the pancreas substance. - opens into the duodenum midway along the 2nd part ​

Question 46

Q. Blockage of the common bile duct will lead to obstruction of the bile flow and subsequent ?

Answer 46

A. Jaundice & disruption to the enterohepatic circulation of bile salts ​

Question 47

Q. Patients will a blockage will have what symptoms?

Answer 47

A. Yellow discolouration, dark urine (conjugated bilirubin)??? & pale stool ​

Question 48

Q. obstructive jaundice is commonly secondary to a

Answer 48

A. tumour ​

Question 49

Q. The most common tumour to cause obstructive jaundice is ? ​

Answer 49

A. A carcinoma of the head of the pancreas, which obstructs the CBD as it passes either through or in close relation to the head of pancreas.

Question 50

Q. Other tumours, which cause obstructive jaundice, include?

Answer 50

A. cholangiocarcinoma (bile duct cancer), adenocarcinoma of the duodenum or extrinsic compression of the bile duct from a tumour in the liver

Question 51

Q. 1. Painful obstructive jaundice is more likely to suggest ? 2. What can measure the diameter of the CBD? Why is this important? 3. Care had to be taken when evaluating patients who have had a previous ERCP as it is likely they will have had a ? 4. Superior to the duodenum the common bile duct runs where? 5. This free edge of omentum is the anterior border of the? 6. What is the Pringle manouver? ​

Answer 51

A. 1. gallstone disease (remember that nothing is ever 100 %). 2. On ultrasound scanning the sonographer will measure the diameter of the CBD to ascertain whether there is any sign of obstruction jaundice, thus it is important to remember that the maximum diameter of the bile duct is 7mm. 3. sphincterotomy & subsequent dilatation 4. In the free edge of the lesser omentum along with the portal vein and hepatic artery. 5. epiploic foramen of Winslow, the entrance to the lesser sac (ask your demonstrator to show you this!). 6. When you apply pressure to the free edge of the lesser sac occluding the portal vein and hepatic artery controlling hepatic haemorrhage. This is utilised in hepatobiliary surgery (this is a very useful manouver).

Question 52

Q. The small intestine varies from 3 to 10 meters in length. It is divided into the ? Is there a demarcation between the sections?

Answer 52

A. jejunum (~2/5) & ileum (~3/5). There is no sharp demarcation between the 2 ​

Question 53

Q. The SI has a mesentery what is its length? Function? Extends to and from?

Answer 53

A. 15cm Attaches the entire small bowel to the posterior abdominal wall from the DJ flexure to the left of L2 passing obliquely to the right sacro-iliac joint. ​

Question 54

Q. Small bowel endoscopy It is relative difficult to examine endoscopically. The traditional methods are push enteroscopy, sonde enteroscopy or intraoperative enteroscopy. Recently technological advances have allowed the development of ?

Answer 54

A. capsule endoscopy ​

Question 55

Q. 1.Why does the Jejunum have a thicker wall? 2. Darker in appearance? 3. How does celiac disease effect the ileum? 4. How does lymphoma effect the small intestine 5. What is Meckel’s diverticulum? Where is it found? 6. What may Meckel’s diverticulum contain? Why is this bad? 7. Signs and symptoms of celiacs disease?

Answer 55

A. 1. Increased no, larger and taller plicae circulares (circular folds of mucosa) than in the ileum. 2. The jejunum also appears a deeper red in colouration due to its greater blood supply from a small number (1 or 2) of large vascular arcades. 3. The juejunal wall has tall villi with deep crypts. In celiac disease these villi and crypts atrophy 4. The small bowel has aggregates of lymphoid tissue within its wall known as Peyer’s patches. The ileum in particular has a large number of Peyer’s patches. These can enlarge particularly in lymphoma and cause intestinal luminal obstruction. 5. May be found in the distal ileum It is a remnant of the embryonic vitellointestinal duct. It is said to be found 2 feet from the ileocaecal valve, occur in 2 % of the population and be 2 inches long (rule of 2’s). 6. It may contain gastric mucosa, which secretes acid. This may cause bleeding or inflammation and should be considered as a differential diagnosis with unexplained GI blood loss or acute abdominal pain 7. The most common signs for adults are diarrhea, fatigue and weight loss. Adults may also experience bloating and gas, abdominal pain, nausea, constipation, and vomiting. - anaemia - tingling in hands and feet

Question 56

Q. Colonoscopy 1. Describe how the large intestine is examined 2. How can the left side of the colon be examined in isolation 3. The entire colon is between 100-180cm and is classically said to be longer in ? despite their smaller stature. 4. The colon is distinguished by? 5. The taenia coli often cause the internal lumen of the colon to appear ? 6. Label the diagram 7. The lengths of muscle are shorter than the colon itself. So how does it run the length of the whole colon? 8. On a plain radiograph of distended colon the sacculations appear as incomplete lines occurs the lumen of the colonic wall. In contrast distended small bowel has?

Answer 56

A. 1. In a retrograde fashion from the anus to the caecum using a colonoscope 2. sigmoidoscope 3. females 4. 3 longitudinal bands of muscle along its length, which form taenia coli and converge at the base of the appendix. 5. triangular. This is especially apparent in the transverse colon. 6. 7. Bunch the colonic wall to form haustrations (sacculations) 8. mucosal folds (valvulae conniventes) project across the entire width of the bowel wall (have a look at some abdominal x-rays on google)

Question 57

Q. The large intestine is subdivided into?

Answer 57

A. Caecum & appendix, ascending, transverse, descending, sigmoid, rectum and anus. ​

Question 58

Q. The ileocaecal junction is marked by a valve, which signifies the start of the large intestine. This valve is formed by?

Answer 58

A. oblique entrance and partial invagination of the ileum into the caecum forming folds ​

Question 59

Q. Function of the valve?

Answer 59

A. The valve prevents back flow of colonic contents during peristalsis ​

Question 60

Q. What may happen to the cecum in large bowel obstruction?

Answer 60

A. The caecum may dilate to the point of necrosis or perforation if the ileocaecal valve is competent as it prevents back flow of excess air and colonic contents which may not pass distally (remember this!). ​

Question 61

Q. The caecum is the first part of the large intestine. It lies in the ?

Answer 61

A. right iliac fossa ​

Question 62

Q. The appendix is a blind ending structure which arises from ? ​

Answer 62

A. the postero-medial aspect of the caecum approximately 3cm below the ileocaecal valve

Question 63

Q. Its position is highly variable due to its embryonic origin as a direct out- pouching on the lateral side of the caecum. The differential overgrowth of the caecal wall causes its medial and often inferior displacement. The appendix orifice can be located endoscopically by?

Answer 63

A. Visualising the convergence of the three taeniae coli at the pole of the caecum (how common is appendicitis?)

Question 64

Q. 20% of colonic tumours occur in the caecum & right side of the colon and often present ?

Answer 64

A. With a mass, change in bowel habit, iron deficiency anaemia or pain ​

Question 65

Q. Ascending colon is 12-20cm long, it passes superiorly from the caecum to the ? where the transverse colon commences.

Answer 65

A. hepatic flexure ​

Question 66

Q. Transverse colon is approximately 45cm in length and is highly mobile. It commences at the ? and traverses the abdomen to the ?

Answer 66

A. hepatic flexure, splenic flexure ​

Question 67

Q. The transverse colon is **highly mobile** and often difficult to **navigate endoscopically**. It is classically said to lie at the level of the?

Answer 67

A. Umbilicus but may hang down into the pelvis

Question 68

Q. This is more common in ? and a possible reason why ~70% of difficult colonoscopies appear to be in the ? population.

Answer 68

A. females x2 ​

Question 69

Q. The sigmoid colon has the largest number of?

Answer 69

A. appendices epiploicae on its outer surface ​

Question 70

What are appendices epiploicae & draw a diagram of one

Answer 70

A. These are fat-filled peritoneal tags found on the colon (except for the caecum or rectum) ​

Question 71

1. Sigmoid (sigmoid shape) colon has an average length of ? but may be as long as 70cm 2. Due to the length of the sigmoid colon and its loose mesenteric attachment it can result in? What symptoms would the patient present with? Treated using? 3. ?% of colon cancers occur in the sigmoid colon

Answer 71

1. 37cm 2. Sigmoid may twist on its self-\> sigmoid volvulus Symptoms of large bowel obstruction & has a classical radiological appearance. It is commonly treated using flexible sigmoidoscopy. 3. 25

Question 72

1. In the western world the sigmoid colon is the most common location of colonic diverticulum (are colonic diverticulum true diverticulum? These are out-pouchings of the bowel wall. Where do they commonly occur? 2. 10% of the population aged 40 have ? compared to 60% of 80 year olds. They may cause diverticular disease, diverticulosis or diverticulosis.

Answer 72

1. They commonly occur at the point where the artery pierces the muscular wall causing a weakness 2. diverticulosis,

Question 73

Q. Rectum (from the Latin straight) is approximately 12cm and commences anterior to the sacrum at ? & leads to the anal canal. Unlike other mammals the human rectum is not straight. It curves anteriorly following the sacrum and then turns at approximately 90degrees through the pelvic diaphragm. It also as 3 lateral curves corresponding with ?

Answer 73

A. S3, mucosal folds or the valves of Houston. ​

Question 74

Q. The rectum appears circular on endoscopic examination despite it having the 3 taenia coli due to ?

Answer 74

A. It’s thick circular muscle layer needed to cope with formed stool. ​

Question 75

Q. The tubular appearance is broken by?

Answer 75

A. Haustral folds ​

Question 76

1. ?% of colon cancers are found within the rectum 2. Inflammation of the colon maybe caused by 2. infection, autoimmune conditions which includes Ulcerative Colitis and Crohn’s and iatrogenic causes such as radiotherapy

Answer 76

1. 50