Electricity: measuring and testing – Particle precession resonance – Using a nuclear resonance spectrometer system
Patent
1995-12-29
1997-02-18
Arana, Louis M.
Electricity: measuring and testing
Particle precession resonance
Using a nuclear resonance spectrometer system
324307, G01V 300
Patent
active
056044356
ABSTRACT:
A method is provided for rapidly measuring change in T.sub.2 * in a region of an MR imaging subject, the method employing a double gradient echo sequence with spiral readout. In this technique, two gradient echoes are acquired after a single RF excitation. A first readout trajectory spirals out from the center of k-space, i.e., k.sub.r =0, to some maximum radius, and then a second readout trajectory spirals back towards the center of k-space. A gradient echo is formed each time a k-space trajectory passes through the center of k-space. The signal intensity of the two echoes allows the calculation of the T.sub.2 * values on a pixel by pixel basis. The ability to measure changes in T.sub.2 * allows measurement of change in perfusion to be quantified.
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Foo Thomas K.
King Kevin F.
Arana Louis M.
General Electric Company
Pilarski John H.
Skarsten James O.
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