MODALITIES OF DIAGNOSTIC TECHNIIQUES Flashcards
What are reasons for why medical investigations occur? (4)
- To screen for things e.g routinemammary screening
- To diagnose
- To evaluate severity of a disorder so treatment can be planned
- Monitoring response to treatment
Give 6 examples of diagnostic modalities
- Endoscopies - through anal canal or urethra up
- ECG - measure heart waves/ rate
- EEG - measures brain waves
- Histopathology - studying tissues
- Imaging - X-rays, MRI, CT, PET
- Basic tests like blood, urine, stool
What factors should you consider when choosing an imaging technique? (4)
- Weigh up advantages and disadvantages
- Look at the patient safety e.g pregnant women can’t have x-rays
- Which one gives the best demonstration of a region
- Cost effectiveness - choose the cheaper option
Give two examples of NON ionising imaging techniques.
- Ultrasound
- MRI
Give 3 examples of ionising imaging techniques where the radiation goes into the body from outside
- CT scan
- Fluroscopy
- X rays Radiography
Give 2 examples of ionising imaging techniques where the radiation goes from the body to outside
- Nuclear imaging
- PET scan
Which technique is best for bones and what colour do they show up as (include specific terminology for colour)
- Standard x ray
- Bones show up as a white colour, soft tissues are a grey colour
- Radial opacity
Explain what a contrast X-ray is
The patient swallows a contrast medium such as barium. This medium stains the structure e.g the oesophagus and this allows any abnormalities to be outlined. An X ray is used as the medium is being swallowed.
Explain what an ultrasound is used for and how it works
An ultrasound is used for soft tissue and glandular tissue. Sound waves from the ultrasound are reflected by the soft tissue. Different types of tissue reflect the waves at different rates. The reflected sound wave will be captured by the probe and show up as an image
What colour does air appear as on an ultrasound?
Black
What can you see in a doppler ultrasound?
Can see blood flow
What can a CT scan be used for?
- Bones and skull fractures
- Has different frames some allow for soft tissue to be seen better and some allow for bones to be seen better
What is an MRI used for?
- Issues in the brain that doesn’t involve bones
- Has good soft tissue discrimination
What colour does air appear as on an x ray?
Black
Difference between standard x ray and CT scan
- X ray looks at dense tissues and CT looks and bones, soft tissues and blood vessels and can see them in more detail
