NMR relaxometry using variable initial flip angle

Details NMR relaxometry using variable initial flip angle NMR relaxometry using variable initial flip angle

1992-07-07

1994-04-26

Tokar, Michael J.

Electricity: measuring and testing

Particle precession resonance

Using a nuclear resonance spectrometer system

324307, G01R 3320

Patent

active

053070151

ABSTRACT:
MRI T1 relaxometry is performed using a single fixed strength magnetic background field for RF signal transmission and reception thus greatly simplifying RF circuitry design and/or adjustment Switched differing strength background magnetic fields are employed at other times in the relaxometry cycle so as to predominate the NMR T1 relaxation parameter value and thus permit relaxometry determinations of T1 values versus magnetic field strength (or the equivalent corresponding NMR RF frequency) at N data points using as few as N+1 measurement cycles. In one embodiment, the booster field is switched on for fixed time intervals .tau. while variable initial NMR nutation pulses .alpha. are utilized as the controlled relaxometry variable parameter. Process and apparatus are disclosed for thus efficiently achieving in vivo NMR relaxometry (including magnetic resonance imaging if desired).

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