Patent ID: 6696889
Filing Date: 2004-02-24
Classification: G01R

Abstract:
A method of acquiring a magnetic resonance signal of a desired hydrogen nucleus 1H existing within an object being examined and being placed in a static field, the method comprising the steps of:applying to the object a first radio-frequency magnetic pulse of which frequency corresponds to a resonance freguency of the desired hydrogen nucleus 1H; applying, after applying the first radio-frequency magnetic pulse, to the object a second radio-frequency magnetic pulse to frequency-selectively excite a specific hydrogen nucleus 1H existing within the object and being coupled to the desired hydrogen nucleus 1H through a homonuclear spin-spin coupling, thus producing a multiple-quantum coherence between the desired hydrogen nucleus 1H and the specific hydrogen nucleus 1H; applying, after applying the second radio-frequency magnetic pulse, to the object a third radio-frequency magnetic pulse of which frequency corresponds to the resonance frequency; applying, after applying the third radio-frequency magnetic pulse, to the object a fourth radio-frequency magnetic pulse to frequency-selectively excite the specific hydrogen nucleus 1H, thus producing a single-quantum coherence of the desired hydrogen nucleus 1H; and acquiring, after applying the fourth radio-frequency magnetic pulse, the magnetic resonance signal of the desired hydrogen nucleus 1H; wherein, in cases where a constant indicating the homonuclear spin-spin coupling is JHH, the second radio-frequency magnetic pulse is applied at a time when a period of time corresponding to â€œ(2m+1)/2nâ€  times as large as an inverse number of the constant JHH elapses from the application of the first radio-frequency magnetic pulse, in which m=0, 1, 2, 3, . . . and n is the number of 1H spins coupled to the desired hydrogen nucleus 1H.