Imaging of Circulatory Disturbances Flashcards Preview

Cardiovascular System > Imaging of Circulatory Disturbances > Flashcards

Flashcards in Imaging of Circulatory Disturbances Deck (22):

What are anatomical vascular imaging methods?

- Plain films
- Contrast angiography
- Ultrasound


What are functional vascular imaging methods?

- Radionuclide imaging
- MRI functional imaging
- Ultrasound


What are problems with vascular imaging?

- Soft tissue contrast
- Functional significance of lesions
- Is treatment effective


What is the problem with using contrasts?

We can't see some important structures very well:
- Blood vessels
- Lumen of hollow viscera


What are the ideal properties of a man-made contrast agent in radiology?

- Inert: won't react with body of tissues
- Painless
- Easy to use


Features of Iodinated contrasts?

- Differential Xray attentuation
- Inert
- Stable in selected body compartments
- Painless
- Easy to use
- Cheap


What are problems with Iodinated contrasts?

- Major reactions
- Renal dysfunction
- Disurbance of thyroid metabolism
- Disturbance of clotting
- Seizures
- Pulmonary oedema


Features of Parental Iodinated contrast

- Metallic taste
- Feeling of warmth
- Arterial injections: Micturition, discomfort
- Rarely nausea


Metformin and contrast agents

Metformin is a drug used to treat type II diabetes
- This can cross react with contrast agents!


Features of catheter angiography

- Vessel punctures and catherised
- Sterile procedure
- Contrast injected using pump injector
- Rapid series of images acquired


Interventional Radiology: minimal invasive treatment techniques

- Angiography/Angioplasty
- Embolisation
- Catheter thrombolysis
- Drainage of abscesses
- Nephrostomy
- Vertebroplasty


When would you use Angioplasty?

- Short stenoses or occlusions
- Sessile/concentric plaques
- Iliac > sfa > popliteal > crural
- "not as long lasting as surgery but not as dangerous"


What else is used apart from Iodine containing contrast agents?

Carbon Dioxide
- A negative contrast agent!
- Useful in patients with poor renal function or sensitivity to iodinated contrast agents.
- CO2 gets absorbed really quickly in vessels.


What are problems with Angioplasty?

- Occlusion
- Dissection
- Embolisation
- Rupture
- Infection


Features of Ultrasound

- No radiation dose
- Quick
- Non-invasive
- Resolution vs Penetration
- May be physiological
- Operator dependant


A man presents with a swollen leg. An ultrasound test confirms a Deep Venous Thrombosis.
What does the ultrasound show?

The vein is distended and non-compressible on gentle pressure of the ultrasound probe


Features of normal vein on ultrasound

Normal vein has low pressure and is compressible

DVT - vein is full of thrombus and is not compressible


What can Radionuclide imaging be used for?

- Perfusion
- Blood loss
- Perfusion of transplant kidneys
- Blood loss into gastrointestinal tract


Features of V/Q (ventilation perfusion scan)

It is useful in the evaluation of pulmonary embolism


Features of Nuclear Medicine

- IV injection only
- Good patient compliance
- Radiation dose
- Very insensitive
- Very non-specific
- Easy to arrange


Features of Computed Tomography Angiogram

- Gives information about other structures
- Sensitive
- IV injection only
- Radiation dose
- High contrast dose
- Expensive


Features of Magnetic Resonance Angiography

- Sensitive
- Specific
- no radiation
- No nephrotoxic contrast
- Very expensive
- Needs state of the art machinery
- High contrast cost