Contrast radiography Flashcards
What is contrast radiography?
- Studying organs using X-rays and a contrast medium (dye)
- Enhances the differences between body tissues on images
What is a negative contrast agent and what does it look like?
- Air
- Black
What is a positive contrast and what does it look like?
- Barium compounds and iodine compounds
- White
Why should plain X-rays be done before a contrast X-ray?
- Might be visible anyway
- Foreign body might be radiodense
- Check exposure factors
- Check patient preparation
When should barium sulphate be used?
- Vomiting
- Diarrhoea
- Suspected mass of foreign body
How should the patient be prepared for barium compounds?
- Starve/enema
- Sedation
When should barium compounds not be used and why?
- Ruptured bowel as can cause granuloma or thrombus and risk aspiration pneumonia patients
- As not water soluble
What are the 2 ways to use contrast in urinary tract radiography?
- IV urography
- Retrograde cystography
What is IV urography?
- Ionic iodine compounds
- Starve, enema, IV canula and GA
What are the indications for IV urography?
- See kidney internal shape
- Pelvis size, shape and position
- Ureter and bladder anatomy
What is cystography?
- Ionic iodine solutions and air
- Enema, GA/sedation, catheterise to drain urine and insert contrast, roll patient to coat bladder and then insert air
What are the indications for cystography?
- Dysuria/haematuria
- Incontinence/urinary retention
- Suspected bladder rupture
What is positive contrast cystography good for and not good for?
- Good for bladder rupture
- Not good for uroliths
What is double contrast cystography good for?
- For detecting uroliths or examine bladder wall
What is myelography?
- Non-ionic iodine compounds
- Surgical prep of site, GA, contrast agent warmed to body temperature, remove cerebrospinal fluid and insert contrast via spinal needle
Which biological macromolecule is the most sensitive to ionisation radiation and what are the consequences to exposure
- DNA
- Carcinogenesis
- Mutagenesis
