Large Bowel Flashcards
Different imaging techniques in the large bowel?
Abdomen x-ray
Barium Emma
CT - colonography
MRI - cholonography
Endorectal ultrasound
Ateriography
Other diagnostic tests of the large bowel:
Faecal occult blood test
Rigid sigmoidoscopy
Flexible sigmoidoscopy
Colonoscopy
 when is an abdomen x-ray useful?
Acute abdominal pain warranting hospital admission – can demonstrate obstruction but not site/cause
Helpful in cases of bowel dilation – sigmoid volvulus or inflammatory bowel disease with suspected toxic megacolon
What is a barium enema?
It is perform did the fluoroscopy sweet
Examination in decline due to CT
Enema kit
Bag with barium sulphate suspension
Enema tube with ballon at end to hold it in position - only blown up post entrance
Barium and air
Ct colongraophy
Replaced barium enema as primary diagnostic tool for colon pathologies
Depends on CT availability
Minimal patient distress
Complete colon examination
Low risk of complications - such as perforation
No sedation required
2D + 3D images of the colon
Barium enema cancer detection - 80-90%
CT colongraphy cancer detection - 95%
Cholongraphy technique:
Prior to appointment:
Low residue diet and picolax - bowel cleansing
Gastografin - bowel tagging
During examination:
Buscopan/glucagon - muscle relaxant
Lubricated catheter inserted and balloon distended
CO2 or air introduced by means of insufflator - bowel distension
Scout view - check distension
Supine and probe CT
Patient care during CT cholongraphy procedure:
Patient changed into radiolucent gown
Total explanation of procedure – LMP if appropriate
Check laxative has been taken and has worked
Extra care when intubating
Infection control – IV cannulation to procedure takes for IV contrast
Possible Tommy camps from air/CO2 – warm feeling/metallic taste - if IV contrast
3D virtual cholongraphy aftercare:
Wait in department for 20 mins
Return to normal eating and drinking patterns
Recommend patient drinks plenty of fluid the next 2-3 days
Warn - possible abdo cramps
Blurring of vision following buscopan - 30 mins
Where/when for results
Severe abdominal pain or unwell seek medical help
MRI what is it used for in bowel imaging:
Good for staging/diagnosis of rectal carcinoma
Good for assessing size of colorectal tumours and also spread
Used for surgical planning
MR cholongraphy advantages in large bowel scanning:
No ionising radiation
Left invasive than colonoscopy
Good for young patients
Diagnosis not limited to bow
Sensitive for abnormality detection
Although it’s  not readily available/economically viable
MR cholongraphy prep:
Same as CT
Very similar to CT
Co2 distension
Good for young patients
Gadolinium IV contrast used for enhancement
Endorectal ultrasound advantages:
Excellent modality for diagnosis and staging of rectal carcinoma
Well tolerated by patients
Arteriography what does it do and how?
Investigates bleeding from lower GI system
Contrast injected into mesenteric artery
If bleed/clot found this can be treated
What does F.O.B. stand for?
Faecal occult blood test
