Imaging and Interventionof

Vascular Emergencies

Masoud Pezeshki Rad, M.D. Assistant Professor of Radiology

Radiology Department of Imam Reza HospitalMUMS

Introduction• Emergency situation deriving from vessels:

1. Bleedinga. Traumatic transsectionb. Rupture of aneurysm, pseudoaneurysm, dissection

2. Thrombosisa. Traumatic vessel injurya. Traumatic vessel injuryb. Hypercoagulability syndromesc. Arteriosclerosis

3. Embolizationa. Foreign body embolizationb. Organ artery or peripheral artery embolizationc. Pulmonary artery embolization

4. Malperfusion syndromesa. Traumatic compression or spasmb. 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 CentralVenous Catheter Fragment

Stenting of Dissection