Abstract: An apparatus for non-destructive testing of a sample includes a sample holder configured to contain or support the sample; an exciter configured to generate an oscillating electromagnetic field across the sample that operates with at least one predetermined excitation frequency; a receiver configured to detect harmonic electromagnetic signals resulting from induced electromagnetic fields oscillating with at least one frequency that is not equal to the at least one predetermined excitation frequency; a recorder configured to record the harmonic electromagnetic signals; and a processor programmed to construct an induced harmonic electromagnetic spectrum based on the harmonic electromagnetic signals.

Abstract: An apparatus for non-destructive testing of a sample includes a sample holder configured to contain or support the sample; an exciter configured to generate an oscillating electromagnetic field across the sample that operates with at least one predetermined excitation frequency; a receiver configured to detect harmonic electromagnetic signals resulting from induced electromagnetic fields oscillating with at least one frequency that is not equal to the at least one predetermined excitation frequency; a recorder configured to record the harmonic electromagnetic signals; and a processor programmed to construct an induced harmonic electromagnetic spectrum based on the harmonic electromagnetic signals.

Abstract: A general framework is for signal encoding in MRF that enables simultaneous transmit and receive encoding to accelerate the acquisition process, or improve the fidelity of the final image/parameter-map per unit scan time. The proposed method and systems capitalize on the distinct spatial variations in the sensitivity profile of each transmit-coil to reduce the acquisition time, and/or improve the fidelity of the final parameter-map per unit time.

Abstract: A method of performing multi-slice acceleration for MR fingerprinting includes obtaining k-space data for MR volumes; applying controlled radio frequency (RF) pulses to the MR volumes; exciting a plurality of slices within the MR volumes by the RF pulses at a same time; and producing a plurality of fingerprints from the plurality of slices. At least one set of fingerprints is compressed, and a residual signal of a plurality of signal evolutions is reduced. The method additionally includes periodically switching a weighting between a first slice and a second slice of the plurality of slices.

Abstract: Systems and methods are disclosed for pseudo steady state magnetic resonance fingerprinting. A representative system includes a magnetic resonance control unit. Radio frequency energy is directed in a sequence to a volume. The sequence includes at least two segments. Each segment contains a series of radio frequency pulse which may be used in concert with a series of gradient waveforms. The first segment is repeated successively until magnetization at a beginning of the segment is stable. This initial magnetization deviates from the equilibrium magnetization. Subsequently, the magnetic resonance control unit produces a plurality of imaging segments which collectively capture a high resolution 3D data set, which encodes at least one relaxation parameter into a MR fingerprint. A short delay time may be inserted between imaging sequences.

Abstract: A method of performing multi-slice acceleration for MR fingerprinting includes obtaining k-space data for MR volumes; applying controlled radio frequency (RF) pulses to the MR volumes; exciting a plurality of slices within the MR volumes by the RF pulses at a same time; and producing a plurality of fingerprints from the plurality of slices. At least one set of fingerprints is compressed, and a residual signal of a plurality of signal evolutions is reduced. The method additionally includes periodically switching a weighting between a first slice and a second slice of the plurality of slices.

Abstract: A method of acquiring PET and MR images simultaneously includes obtaining raw k-space data for continuous MR volumes and acquiring PET information. The method further includes performing a joint multi-modality image reconstruction and generating a set of PET and MR images. The method additionally includes generating a set of MR fingerprints from the reconstructed MR images and using the MR fingerprints to generate a set of parameter maps.

Abstract: A general framework is for signal encoding in MRF that enables simultaneous transmit and receive encoding to accelerate the acquistion process, or improve the fidelity of the final image/parameter-map per unit scan time. The proposed method and systems capitalize on the distinct spatial variations in the sensitivity profile of each transmit-coil to reduce the acquistion time, and/or improve the fidelity of the final parameter-map per unit time.

Abstract: Systems and methods are disclosed for pseudo steady state magnetic resonance fingerprinting. A representative system includes a magnetic resonance control unit. Radio frequency energy is directed in a sequence to a volume. The sequence includes at least two segments. Each segment contains a series of radio frequency pulse which may be used in concert with a series of gradient waveforms. The first segment is repeated successively until magnetization at a beginning of the segment is stable. This initial magnetization deviates from the equilibrium magnetization. Subsequently, the magnetic resonance control unit produces a plurality of imaging segments which collectively capture a high resolution 3D data set, which encodes at least one relaxation parameter into a MR fingerprint. A short delay time may be inserted between imaging sequences.