L2-Safety - Zhong-Lin Lu Laboratory of Brain...

Info icon This preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Zhong-Lin Lu Laboratory of Brain Processes (LOBES) Dana and David Dornsife Cognitive Neuroscience Imaging Center University of Southern California
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
1) Put subject in big static magnetic field [e.g., 3 T] 2) Transmit radio waves into subject [about 3 ms] 3) Turn off radio wave transmitter 4) Receive radio waves re-transmitted by subject Manipulate re-transmission with magnetic fields during this readout interval [10-100 ms: MRI is not a snapshot] 5) Store measured radio wave data vs. time Now go back to 2) to get some more data 6) Process raw data to reconstruct images The basic MRI procedure
Image of page 4
MRI/fMRI utilizes a very strong static magnetic field, time varying smaller magnetic fields (‘gradients’) and an electromagnetic, radio frequency field to create images. The static field is time invariant and is always on. The radio frequency electromagentic field (B1) used to excite the spins, and the gradient magnetic fields used to spatially encode, are rapidly turned on and off during scanning. Coils are used to create these fields, imposing a particular geometry upon the device itself. Finally, the ramping up and down of the gradient fields causes the coils to vibrate, causing loud noise associated with scanning.
Image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.
  • Spring '08
  • Lu
  • Magnetic Field, main safety risk, David Dornsife Cognitive Neuroscience Imaging Center University of Southern California

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern