Imaging of Circulatory Disturbances Flashcards
What are the different types of functional vascular imaging?
Radionuclide imaging
MRI functional imaging
Ultrasound
What issues have to be considered when using vascular imaging techniques?
Soft tissue contrast
Functional significance of the lesions
If the treatment is effective
What is the problem with radiographic and natural contrast?
Cant see blood vessels or the lumen of hollow viscera very well
What are some problems with Iodinated contrast?
Major reactions Renal dysfunction Disturbance of thyroid metabolism Disturbance of clotting Seizures Pulmonary oedema
What are the different types of anatomical vascular imaging?
X rays
Contrast angiography
Ultrasound
CT/MRI
With radiographic contrast what appears black and what appears white?
Air appears black
Fat appears grey
Soft tissue appears white
What are the benefits of using iodinated contrast?
Stable in selected body compartments
Painless
Easy to use
Cheap
What are somethings that have to be considered before administering parenteral iodinated contrast?
Previous contrast allergy
Asthma/atopy
Poor renal function
Metformin
How is catheter angiography done?
- Vessel punctured and catheterised
- Contrast injected using pump injector
- Rapid series of images acquired
What is done using interventional radiology?
Angioplasty/angiography Embolisation Catheter thrombolysis Drainage of abscesses Nephrostomy Vertebroplasty
When should angioplasty be used?
Short stenoses
Occlusions
Sessile/concentric plaques
What type of contrast agent is carbon dioxide?
A negative constant agent
When is carbon dioxide a useful contrast agent?
In patients with poor renal function and in patients sensitive to iodinated contrast agents
What are the possible problems with angioplasty?
Occlusion Dissection Embolisation Rupture Infection
What are the benefits of ultrasound?
No radiation
Quick
Non invasive
What is the problem with ultrasound?
Operator dependant
In terms of ultrasound what is the difference between a normal vein and DVT vein?
Normal vein has low pressure and is compressible
DVT vein is full of thrombus and not compressible
What are the applications of radionuclide imaging?
Perfusion
Blood loss
What are the benefits of nuclear medicine?
IV injection only
Good patient compliance
Easy to arrange
What are the negatives of nuclear medicine?
Radiation dose
Very insensitive
Very non-specific
What are the benefits of a CT angiogram?
Sensitive
IV injection only
Gives info about other structures
What are the negatives of a CT angiogram?
Radiation dose
High contrast dose
Expensive
What is the benefit of magnetic resonance angiography?
Sensitive
Specific
No radiation
No nephrotoxic contrast
What are the negatives of magnetic resonance angiography?
Very expensive
High contrast cost
Needs state of the art machinery
What is involved in getting consent in radiology?
A process in which a patient learns key facts about an investigation/ treatment, including potential risks and benefits, before deciding whether or not to proceed and then informed consent continuous throughout the procedure
