Simultaneous parallel inclined readout image technique.

Martyn N J Paley; Kuan J Lee; James M Wild; Paul D Griffiths; Elspeth H Whitby

doi:10.1016/j.mri.2005.12.019

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Simultaneous parallel inclined readout image technique.

Martyn N J Paley·Kuan J Lee·James M Wild·Paul D Griffiths·Elspeth H Whitby

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Abstract

Sensitivity-encoded phase undersampling has been combined with simultaneous slice excitation to produce a parallel MRI method with a high volumetric acquisition acceleration factor without the need for auxiliary stepped field coils. Dual-slice excitation was produced by modulating both spin and gradient echo sequences at +/-6 kHz. Frequency aliasing of simultaneously excited slices was prevented by using an additional gradient applied along the slice axis during data acquisition. Data were acquired using a four-channel receiver array and x4 sensitivity encoding on a 1.5 T MR system. The simultaneous parallel inclined readout image technique has been successfully demonstrated in both phantoms and volunteers. A multiplicative image acquisition acceleration factor of up to x8 was achieved. Image SNR and resolution was dependent on the ratio of the readout gradient to the additional slice gradient. A ratio of approximately 2:1 produced acceptable image quality. Use of RF pulses with additional excitation bands should enable the technique to be extended to volumetric acquisition acceleration factors in the range of x16-24 without the SNR limitations of pure partially parallel phase reduction methods.

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Algorithms Computing Methodologies Image Enhancement Image Interpretation, Computer-Assisted Imaging, Three-Dimensional Information Storage and Retrieval Magnetic Resonance Imaging Phantoms, Imaging Reproducibility of Results Sensitivity and Specificity User-Computer Interface Evaluation Study Journal Article Research Support, Non-U.S. Gov't

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Martyn N J Paley, Kuan J Lee, James M Wild, Paul D Griffiths, Elspeth H Whitby. 2006-03-06. Simultaneous parallel inclined readout image technique.. https://doi.org/10.1016/j.mri.2005.12.019

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