Through modification of the phase-encoding gradient, a method and
apparatus increases the effectiveness of a Magnetic Resonance Imaging
(MRI) device by decreasing scan time without noticeably decreasing the
signal-to-noise ratio. In an MRI device, a patient is subjected to a
constant magnetic field, and then radio frequency (RF) pulses are used to
excite the nuclei in the patient's body. The nuclei release a
corresponding RF signal as the nuclei relax, which can be measured and
mapped into a visual display. The RF pulses used to excite the nuclei in
the body cooperate with a slice select gradient and a phase-encoding
gradient. When the phase-encoding gradient is indexed and prioritized
according to contribution to image quality, then phase-encoding values
with little or no contribution to image quality need not be acquired but
may be replaced with randomized system noise, thereby decreasing total
scan time without reducing the signal-to-noise ratio.