A MedTech West seminar: Under-sampled reconstruction techniques for accelerated magnetic resonance imaging

NOTE! Monday is the last day to register to receive the light lunch.

Introduced by professor Stephan Maier, Department of Radiology at Sahlgrenska University hospital and presented by Mohammad Kayvanrad, PhD, from Robarts Research Institute at the University of Western Ontario

Due to physical and biological constraints and requirements on the minimum resolution and SNR, the acquisition time is relatively long in MRI. Accelerating the acquisitions without compromising the imaging quality has been an active field of research since the introduction of this modality. This talk concerns under-sampled reconstruction techniques for acceleration of MRI acquisitions, i.e., parallel imaging and compressed sensing.

While compressed sensing MRI reconstructions are commonly regularized by penalizing the decimated wavelet transform coefficients, the visual artifacts, associated with the lack of translation-invariance of the wavelet basis in the decimated form, can be avoided by penalizing the undecimated coefficients, i.e., the stationary wavelet transform.

Additionally, in applications involving multiple acquisitions, e.g., quantitative MRI, the correlation between the successive acquisitions can be incorporated as an additional constraint for joint under-sampled reconstruction, resulting in improved reconstruction performance.
While quantitative measures, e.g., reconstruction error, are commonly used for the evaluation of under-sampled reconstructions, such measures do not necessarily correlate with the subjective quality perceived by radiologists and other expert users. Therefore, unless accompanied by subjective evaluations, quantitative metrics will be of limited clinical impact. The results of experiments aimed at subjective evaluation/comparison of under-sampled reconstructions for specific clinical neuroimaging applications are presented.


Date: September 17, 2014
Time: 11:30-12:15 (-13:00 incl lunch)
Location: At the New MedTech West House, Röda stråket 10B, Sahlgrenska University Hospital