Abstract: A digital interface subsystem, for a magnetic resonance imaging and spectroscopy system, has an internal data bus interconnecting: a master sequencer, receiving instructions from a main system computer; a plurality of controlled generators for providing gradient-field, RF modulation and other required signal waveforms for proper excitation of a sample; and circuitry for analyzing the magnetic resonance response signals from the sample, responsive to the excitation signals for providing image information.

Abstract: A magnetic resonance system for both imaging and spectroscopy of a sample of non-magnetic material (such as a portion of the human anatomy and the like) at one static magnetic field magnitude in excess of 0.7 Tesla (T), utilizes a superconducting magnet having a room-temperature bore of diameter sufficiently large to place therein not only the desired sample but also a set of gradient magnetic field-producing coils and at least one radio-frequency coil for exciting and/or receiving response signals from the sample to be examined. The entire magnetic system has suitably-small temporal and positional field variations to allow imaging to be accomplished at the resonant frequencies of nuclei including .sup.1 H, .sup.13 C, .sup.19 F, .sup.23 Na and .sup.31 P. The system includes a novel interface subsystem, itself including a novel gradient signal switching circuit, for acquiring imaging data in relatively short time intervals.

Abstract: A gradient field switch, for use in an improved nuclear magnetic resonance imaging and spectroscopy system, includes a control portion and a switching portion. The switching portion receives a plurality of magnetic field gradient signals and connects each signal to an associated one of at least the same plurality of outputs. The exact pattern of input-output interconnections is established by the control portion responsive to data received after the presence of a reset signal. By appropriate control data input, the gradient field signals can be routed to axes of a predetermined coordinate system, such that images of a sample can be obtained from several directions, responsive to command signals and without requiring physical movement of the sample being imaged.

Abstract: Power line interference artifacts in a magnetic resonance image are minimized by the process of: providing a sequential plurality of imaging signal sequences, the totality of which sequences is required for determining the value of each image pixel in an image array thereof; requesting the start of each sequence of the plurality of imaging signal sequences prior to the actual time at which each such signal sequence should commence; preparing a recognition element prior to the desired actual commencement time; recognizing a predetermined occurrence of a repetitive power line signal parameter to provide a first signal; setting the recognition element responsive to the first signal to only then cause the signal sequence start request to actually cause commencement of the associated signal sequence; and causing each signal sequence to occur in essentially an integral number of sequential repetitive cycles of the power line signal waveform to minimize the magnitude of power line frequency signal interference artif