Ct Colonography Flashcards
Which cancer is The second most common in europeeurope
Colorectal cancer
Around 447,000 new cases in 2012
Which are the 4 most common cancers in the UK
- Breast
- Lung
3 prostate - Colorectal
why is colorectal cancer under diagnosed? Leaning to death
Embarrassment, misdiagnosis, difficulty with treatment due to location, age at diagnosis
where are the 5 areas that referrals come from?
- GI
- Colorectal
- GP
- Failed colonoscopy
- BCSP - bowel cancer screening program
What is included in the referral/ prep pack?
- Colon prep pack
- appointment letter
- 100 ml gastrografin with instructions
- Diet sheet
- sachet of picolax
What do patients need to do 2 days before the exam?
Low fibre and fat diet
What do patients need to do 1 day before the exam?
Drink 1/3rd of the gastrografin at 3 intervals during the day
What are patients advised not to do on the day of the exam?
Not to eat - they can drink clear fluids
When wouldn’t we give contrast?
- Poor eGFR
- Poor eGFR and on Metformin
- allergy to iodine or the contrast
- severe uncontrolled asthma
- Innterleukin treatment (immunotherapy)
- thyroid condition
- BSCP
When wouldn’t we give Buscopan?
~ allergy to Buscopan or any of the ingredients
~ heart conditions - eg: AP, angina etc
~ Hypertension
~ particularly frail patients
~ any blood thinners
~ poor historian
What are the normal side effects of Buscopan?
Dry mouth
Blurred vision
Constipation
An increased HR
Why is it important for the patient to have followed the diet?
Fat and fibre can show up on the scan.
What slice thickness is used for the cT colon scan?
1.25mm
What phase is the CT colon scan in?
Portal venous
What position is the patient in for the scan?
Ideally prone
Why do we do second and third scans?
To ensure the full lumen is visualised
In what positions the second and third projections completed
Lateral decubitus and supine
Why are second and third scans are lower dose?
Because we dont need to see any soft tissue detail as it has already been seen on the first scan.
Generally 1/3 of the dose of a regular Abdopelvis scan
What properties do the 2nd and 3rd scans have?
Higher noise index
What’s special about the post processing of CT colons?
The radiographer submit a provisional report
What are common findings on CT colonography?
Diverticulitis
Diverticulosis
Polyps
Colorectal cancer
Extracolonic pathology
What is diverticulitis?
Inflammation in the bowel
What is diverticulosis?
Pockets in the bowel wall
What are polyps?
Mucosal outgrowths of the bowel wall
Can lead to colon cancer
What presents with symptoms similar to diverticulitis?
Colon cancer - A disease of the elderly
What do we need to do if colorectal cancer is initially found?
Include a CT chest
