Carotid imaging modalities
This presentation is the property of its rightful owner.
Sponsored Links
1 / 20

Carotid Imaging Modalities PowerPoint PPT Presentation


  • 161 Views
  • Uploaded on
  • Presentation posted in: General

Carotid Imaging Modalities. Kyle Boyce August 3, 2007. Leading Causes of Death in U.S. 1. Heart Disease 2. Cancer 3. Stroke (2 nd leading cause Worldwide) Carotid Artery Atherosclerosis – 7% of patients presenting with initial stroke. Non-modifiable Age Race Gender Family History

Download Presentation

Carotid Imaging Modalities

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Carotid imaging modalities

Carotid Imaging Modalities

Kyle Boyce

August 3, 2007


Leading causes of death in u s

Leading Causes of Death in U.S.

  • 1. Heart Disease

  • 2. Cancer

  • 3. Stroke (2nd leading cause Worldwide)

    • Carotid Artery Atherosclerosis – 7% of patients presenting with initial stroke


Risk factors

Non-modifiable

Age

Race

Gender

Family History

Genetics

Modifiable

*HTN*

Hyperlipidemia

Diabetes

Smoking

EtOH

High Homocysteine

Low Folate

Risk Factors


Brief review pathophysiology

Brief Review - Pathophysiology

  • Fatty streaks

    • Intimal thickening

  • Fibrous Plaque

    • Increased Smooth muscle cells

    • Accumulation of connective tissue

    • Lipid pool

  • Advanced lesions

    • Re-vascularized

    • Necrotic lipid-rich core


Carotid atherosclerosis progession of dz

Carotid Atherosclerosis – Progession of Dz


Cerebrovascular symptoms

Cerebrovascular Symptoms

  • Ipsilateral Partial or Complete Blindness

  • Absent Pupillary Light Response

  • Contralateral Hemianopsia

  • Contralateral Hemiparesis

  • Contralateral Sensory Loss

  • Aphasia (Left Hemisphere Ischemia)

  • Left visuospatial Neglect (Right Hemisphere)

  • Atypical findings include Limb shaking and Syncope (not generally considered a result of carotid stenosis)


Measuring degree of stenosis

Measuring Degree of Stenosis

Currently, three methods (NASCET, ECST and CC) predominate worldwide.


Imaging

Imaging

  • Carotid Duplex Ultrasound

  • CT angiography

  • MR angiography

  • Cerebral Angiography (gold standard)


Carotid duplex u s

Carotid Duplex U/S

  • Uses B-mode ultrasound imaging and Doppler ultrasound to detect focal increases in blood flow velocity

  • The peak systolic velocity is the most frequently used measurement to gauge the severity of the stenosis

  • end-diastolic velocity, spectral configuration, and the carotid index provide additional information


Carotid duplex u s1

Advantages

Non-invasive

Safe

Inexpensive

High Sensitivity and Specificity for significant stenosis (70-99%)

Disadvantages

Overestimates the degree of stenosis

May miss hairline lumens

Limitations

Carotid Duplex U/S


Ct angiography

CT Angiography

  • Use of x-rays to visualize arterial and venous blood flow

  • Create cross-sectional images which then are assembled by computer into a three-dimensionalpicture

  • Provides an anatomic depiction of the carotid artery lumen and allows imaging of adjacent soft tissue and bony structures.


Ct angiography1

Advantages

anatomical detail of blood vessels more precisely than MRA or U/S

Disadvantages

CI in pt’s with renal insufficiency or severe DM

Risk of Allergic rxn

Radiation exposure

CT Angiography


Magnetic resonance angiography

Magnetic Resonance Angiography

The electromagnetic energy that is released when exposing a patient to radiofrequency waves in a strong magnetic field is measured and analyzed by a computer

Most often used for evaluating the extracranial carotid arteries.

Utilize either three dimensional time-of-flight MRA or gadolinium-enhanced MRA (contrast enhanced MRA).


Magnetic resonance angiography1

Advantages

Great imaging w/o use of contrast or radiation

CEMRA – higher quality image with less artifact

No catheter in area of interest

May be most accurate non-invasive method

Disadvantages

May overestimate degree & length of stenosis? Use NASCET

CI for pt’s with metallic implants

CI in patients with renal insufficiency

Magnetic Resonance Angiography


Cerebral angiography

Cerebral Angiography

  • Cerebral angiography is the gold standard for imaging the carotid arteries.

  • The development of intraarterial Digital Subtraction Angiography (DSA) has largely replaced conventional angiograpy

    • Lower dose of contrast

    • Small catheters

    • Shorter procedure


Cerebral angiography1

Advantages

Evaluates entire carotid a. system

Information about the disease process

Assess collaterals

Disadvantages

Invasive

Expensive

Radiation exposure

Potential for stroke

Limited views of carotid & bifurcation

Cerebral Angiography


Carotid imaging modalities

<50 %

> 50%

CEA more beneficial for asymp men

with 60-99% stenosis who are

good surgical candidates


Carotid imaging modalities

May be benefit with 50 to 69% symptomatic stenosis (clearly shown in men but not women)


References

References

  • Up to date Online. Pathophysiology of Symptoms from Carotid Artery Atherosclerosis. Last revised May 1, 2006.

  • Up to Date Online. Evaluation of Carotid Artery Stenosis. Last revised June 22, 2006.

  • Rothwell, PM, Gibson, RJ, Slattery, J, et al. Equivalence of measurements of carotid stenosis. A comparison of three methods on 1001 angiograms. Stroke 1994; 25:2435.

  • Zwiebel, WJ. Duplex sonography of the cerebral arteries: Efficacy, limitations, and indications. AJR Am J Roentgenol 1992; 158:29.

  • Bowen, BC, Quencer, RM, Margosian, P, Pattany, PM. MR angiography of occlusive disease of the arteries in the head and neck: Current concepts. AJR Am J Roentgenol 1994; 162:9.


  • Login