Imaging and Intervention
of
Vascular Emergencies
Masoud Pezeshki Rad, M.D.
Assistant Professor of Radiology
Radiology Department of Imam Reza Hospital
MUMS
Introduction
• Emergency situation deriving from vessels:
1. Bleeding
a. Traumatic transsection
b. Rupture of aneurysm, pseudoaneurysm, dissection
2. Thrombosis
a. Traumatic vessel injurya. Traumatic vessel injury
b. Hypercoagulability syndromes
c. Arteriosclerosis
3. Embolization
a. Foreign body embolization
b. Organ artery or peripheral artery embolization
c. Pulmonary artery embolization
4. Malperfusion syndromes
a. Traumatic compression or spasm
b. Static or dynamic true lumen compression in dissection
What Modalities Are Available?
• Modalities using X-ray
• Angiography
• Computed Tomography – CTA
• Doppler Ultrasound • Doppler Ultrasound
• Magnetic Resonance Imaging – MRA
Angiography
• Conventional
• DSA
Advantages and Disadvantages of
Angiography
• Advantages:
• Fluoroscopy is an excellent tool for image based
interventional procedures
• Disadvantages:• Disadvantages:
• Invasive
• Radiation exposure
• Risks associated with use of contrast agents
Some Risks Associated With Use of Vascular
Contrast Agents
• Contrast allergies
• Death from idiosyncratic anaphylactoid reactions: 1/100,000
• Increased in asthmatics, prior reactions
− Premedication with steroids, H1 (diphenhydramine) and H2 blockers (ranitidine)
• Induced renal failure
• Diabetics, Myeloma, dehydration, renal failure, sickle cell disease. • Diabetics, Myeloma, dehydration, renal failure, sickle cell disease.
• Nephrotoxic meds – aminoglycosides, NSAIDS
• Hydrate, stop nephrotoxic meds, minimize dose of contrast used
• Metabolic acidosis – diabetics on metformin
• Stop metformin after scan X 48 hrs and monitor renal function
• Catecholamine release in pheochromocytoma
Computed Tomography- CT
Spiral or Helical CT
CT Angiography
Strengths and Weaknesses of Computed
Tomography
• Strengths
• Good soft tissue contrast
• 3D image rendering
• Weaknesses• Weaknesses
• Availability
• Radiation
• Contrast complications
• Artifact with metals
Doppler Ultrasound
Doppler
Strengths and Weaknesses of US
• Strengths
• Real time imaging
• able to direct interventions
• Inexpensive and quick
• No radiation
• Portable• Portable
• Weaknesses
• Technical difficulty
• Operator dependence
• Need a good acoustic window
Magnetic Resonance Imaging – MRI
MR Angiography
Strengths and Weaknesses of MRI
• Strengths
• Excellent soft tissue contrast
• Multi-planar
• Not invasive
• No radiation
• Gadolinium IV contrast is not nephrotoxic and may be used in setting of
renal failurerenal failure
• Weaknesses
• Availability/cost
• Time
• Poor bone detail
• Claustrophobia
• Metal and other artifacts
• Risk of complications related to magnetic metal implants (pacemakers,
aneurysm clips etc,)
• Rare serious contrast reactions
Which One Is The Best?
• Doppler Ultrasound
• Computed Tomography – CTA
• Angiography • Angiography
Interventional Procedures
Embolization of Bleeding Vessels
Once arteriography has
demonstrated the bleeding
site, the offending vessel
can then be embolized. can then be embolized.
Stent Grafting of Aneurysms
Thrombolysis
Endovascular Retrieval of a Central
Venous Catheter Fragment
Stenting of Dissection
