2) Imaging the Urinary System Flashcards
What is a radiograph?
Image of internal structure by sending X-rays through the body, which are absorbed in different amounts depending on tissue density
What are the advantages of using X-rays?
Cheap
Non-invasive
Painless
Used for renal stones (calcium oxidate)
What are the disadvantages of using X-rays?
Small increased risk of cancer
What is an intravenous urogram?
Injection of radiopaque contrast dye into vein in arm and following the time course of excretion through urinary system
Contrast dye dense, so white on X-ray
What are the advantages of using IVU?
Clearly see points where flow isn’t good
Visualise narrowings or stones
Cheap
What are the disadvantages of using IVU?
Replaced by CT/MRI
What is ultrasound?
Use of high frequency sound waves to create images inside the body, converts returning echoes to picture
What are the advantages of using ultrasound?
Non-ionising radiation
Non-invasive
Accessible and cheap
What are the disadvantages of using ultrasound?
Operator dependent
Special preparations required
What is computed tomography?
Combines multiple X-ray projections from different angles to produce detailed cross-sectional images of inside the body
What are the advantages of using CT?
Quick Painless Good for stones, tumour, infection, trauma Used to check for recurrence Can do angiogram
What are the disadvantages of using CT?
Risks greater than X-ray
Injection of contrast may cause kidney problems
What is magnetic resonance imaging?
Use of magnetic fields and radiowaves to show cross-sectional images of organs, soft tissues and bones
What are the advantages of using MRI?
Non-invasive
No ionising radiation
Helps diagnosis
What are the disadvantages of using MRI?
Lengthy and noisy
Movement ruins image
Can’t be undertaken in some situations e.g. pacemaker
Claustrophobic dye may cause kidney problems
