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Flashcards in imaging in cancer Deck (20):
1

what are some imaging techniques that can be used in diagnosing and staging cancer?

plain radiographs
barium studies
CT
MRI
(not imaging strictly) -endoscopy and biopsy

2

what colour does barium appear on the radiograph?

white

3

what would a barium swallow and meal allow us to look at?

oesophagus, stomach and duodenum

4

what would a barium enema allow us to look at?

large bowel

5

what would a barium follow through allow us to look at?

small bowel

6

how would a patient prepare for a barium meal and follow through?

fast for 4-6 hours

7

how would a patient prepare for a barium enema?

low residue diet for 48 hours and bowel cleansing

8

what happens in computed tomography (CT)

xrays produce a digital image of a slice of tissue, usually in an axial plane using computing to create the image

9

what is a voxel?

volume of tissue represented by a pixel in a CT slice

10

what is a hounsfield unit'?

the attenuation value of a voxel relative to the attenuation value of water

11

what contrast agents can be used in CT?

iodine based contrast agents can be used orally and intravenously

12

what factors are taken into account when diagnosing and staging cancer?

position of tumour
depth of penetration of tumour
relationship to adjacent structures - SIZE (T)
involvement of regional lymph nodes (N)
presence of distant metastases (M)

13

what kinds of tumours are diagnoed using CT?

pancreatic
renal
adrenal
retroperitoneal
brain

14

what is the radiation dose for chest, abdomen and pelvic CTs respectively?

chest - 8mSv
abdomen and pelvis - 10mSv

15

what does ALARA stand for?

as low as reasonably acheivable - aims to reduce number of exposures

16

what are the advantages of MRI?

excellent bone and soft tissue detail
vessels can be demonstrated

17

when would MRI use be indicated?

brain
spine
musculoskeletal
abdomen
pelvis
cardiac imaging

18

what are some contraindications of MRI?

claustrophobic and noisy
hard to image lungs
cannot image patients with metal implants

19

what is an example of a contrast agent used in MRI?

gadolinium DTPA - some tumours and vascular lesions can be more easily seen

20

what should screening tests aim to acheive?

should detect disease at an early stage where treatment can alter outcome
test should cause no harm
test should have high sensitivity and specificity
benefit to individual and population should outweigh the cost