Physics and Safety

Part of the Contemporary Cardiology book series (CONCARD)
  1. 1.
    The magnetic field strength (1.5 T) routinely used for cardiovascular magnetic resonance imaging (CMR) is:
    1. A.

      Roughly equal to the earth's magnetic field

    2. B.

      One hundred times stronger than the earth's magnetic field

    3. C.

      One thousand times stronger than the earth's magnetic field

    4. D.

      Thirty thousand times stronger than the earth's magnetic field

    5. E.

      One hundred and twenty thousand times stronger than the earth's magnetic field


    Correct answer is D.

    The strength of a magnetic field may be measured in tesla (T) or gauss. One tesla is equal to 10,000 gauss. The earth's magnetic field at the earth's surface varies between 0.3 and 0.6 gauss. Most clinical CMR scanners use a magnetic field of 1.5 T, or 15,000 gauss, i.e., approximately 30,000 times stronger than the earth's magnetic field. [1, 2]

  2. 2.
    For magnetic resonance imaging (MRI), the signal that is used to create the image is emitted from:
    1. A.

      The carbon-12 nuclei (C12)

    2. B.

      The oxygen-16 nuclei (O16)

    3. C.

      The nitrogen-14...


Cardiovascular Magnetic Resonance Correct Answer Magnetic Field Strength Implantable Cardiac Defibrillator Inversion Recovery Sequence 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Humana Press, a part of Springer Science + Business Media, LLC 2008

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