Week 10: Gastrointestinal Pathologies Part 2 Flashcards
1
Q
Crohn’s Disease
A
- chronic inflammatory disorder of unknown cause most often in young adults
- usually in terminal ileum of small bowel and/or proximal portion of the colon (Crohn’s colitis)
- involves all layers of the GI tract
- may have healthy and diseased areas interspersed
- diffuse inflammation causes bowel loops to bind together
- ulceration is common, as well as fistulas to bowel and other organs
2
Q
Crohn’s Disease Radiographic Appearance
A
- barium studies are done
- irregular thickened and distorted mucosal folds
- string sign = narrowed stretch of bowel with no mucosal pattern
- skip lesion = diseased segments separated by healthy segments
- transverse and longitudinal ulceration produces cobblestone appearance
- CT also demonstrates thick mucosal walls
2
Q
Small Bowel Obstruction
A
- blockage of the small intestine
- due to adhesions from previous surgeries, peritonitis, hernias, intussusception, volvulus, tumours or vascular insufficiency
- may produce ischema with subsequent necrosis of bowel segment, sepsis and peritonitis
3
Q
Adynamic (Paralytic) Ileus
A
- fluid and gas (and any bowel contents) do not progress normally through a non-obstructed small (or large) bowel
- can be post op, peritonitis, medication, trauma
- part or all of small/large bowel fills to being peristalsis
- localized ileus = small part of small or large bowel affected
- colonic ileus = large bowel affected
- treatment: NG tube, IV fluids
3
Q
Inguinal Hernia Radiographic Appearance
A
protruding parts may be visible on imaging, not contained within abdominal cavity
3
Q
Small Bowel Obstruction Radiographic Appearance
A
- seen best on upright or decubitus abdomen
- air fluid levels will be seen
- loops of bowel will be distended/dilated proximal to the obstruction and collapsed distally
- small bowl loops may distend so much they look like large bowel
- may look like a step ladder or cascade
4
Q
Localized Ileus
A
- isolated distended loop (sentinel loop)
- due to adjacent inflammatory process
- radiographic appearance: one very distended loop
5
Q
Colonic Ileus
A
- excessive gaseous distention of bowel
- often see massive distention of cecum
- can look like mechanical obstruction (BE to rule out obstruction)
- radiographic appearance: retention of large amounts of gas and fluid in dilated small and large bowel with no demonstrate point of obstruction
5
Q
Inguinal Hernia
A
- some of the abdominal contents, usually part of the small bowel, protrude through a weak are in the abdominal wall at the inguinal canals (one on either side of groin)
- peritoneal sac bulges out too and surrounds the protruded contents
- the hernia may persist outside or slide in and out of the abdomen
- can cause constriction and/or ishcemia of protruding part
6
Q
Intussusception
A
- telescoping of one part of the intestinal tract into another because of peristalsis
- can compromise the vascular supply = ischemic necrosis of the intussuscepted bowel
- most common site in children: ileocecal valve
- major cause of bowel obstruction in children
7
Q
Intussusception Radiographic Appearance
A
- xray: coiled spring appearance on contrast enema
- CT: three concentric circles forming of soft tissue mass; target sign
- us: donut shaped lesion
8
Q
Hemangiomas - Benign Vascular Tumours
A
- occur anywhere along the GI tract, most often in the small bowel, then large bowel and rectum
- may cause bleeding
- radiographic appearance: contrast displacing mass on contrast study
9
Q
Diverticulum/Diverticulosis Radiographic Appearance
A
- multiple round or oval outpouchings from bowel
- thickened circular muscle may show sawtooth configuration
10
Q
Diverticulum/Diverticulosis
A
- diverticulum (single)/diverticula (plural) are out pouchings (herniations) of mucosa and submucosa through the muscular layers at points of weakness in the bowel wall
- lack of fibre and water in the digestive track can lead to development
- many diverticula = diverticulosis, may cause lower GI bleed
- diverticula can occur in esophagus or duodenum
10
Q
Polyps
A
- benign neoplasms that project into the lumen of the bowel
- mostly asymptomatic but certain types can become cancerous
- colonoscopy can find and remove
- found mostly in descending and sigmoid colon
