MRI Physics 1: Image Acquisition. Chris Rorden & Paul Morgan Magnetic Resonance Radio frequency absorption Relaxation: Radio frequency emission Gradients Increases signal/noise: antenna selection, field strength. Excellent references: www.cis.rit.edu/htbooks/mri/
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.
~x60,000 earth’s field strength
The rate of rotation is determined by the strength of the magnetic field.
f = B0
For Hydrogen, = 42.58 MHz/T
At 1.5T, f = 63.76 MHz
At 3T, f = 127.7 MHz
Resonance Frequency (MHz)
Field Strength (Tesla)
Raw image is 2D Frequency Map.
Apply Fourier Transform to reconstruct image.
Source: Traveler’s Guide to K-space (C.A. Mistretta)
Slice 1Sequential vs Interleaved Volumes
Effects of SENSE factor (R) on EPI