Meeting Banner
Abstract #0218

Automatic Off-Resonance Correction with Piecewise Linear Autofocus

SUMMA25Travis Smith1, Krishna Nayak1

1Electrical Engineering, University of Southern California, Los Angeles, CA, United States

We present a new method to correct off-resonance blurring in spiral and radial images without knowledge of the field map. The image is divided into blocks and linear field map estimation and correction are performed on each block. The local linear coefficients are estimated through a combination of k-space spectral analysis and mapdrift, an image-domain correlation technique. The deblurring performance is comparable to field map-based techniques. The method does not use objective functions, requires only a blurry image (magnitude and phase) and a trajectory time map, and is suitable for low-SNR and fine-resolution images.

Abstract PDF Presentation Video

Keywords

acceptable access achieved acquisitions agreement alternative apparent applied apply arrows artery artifacts attenuation automatic better block blocks blurring borders causes chest circle coefficient coefficients comes comparable conjunction constant corrected correction correlate correlating correlation crosses discontinuities discuss dividing domain dynamic electrical engineering entire error estimating estimation example examples except exhibits fast featureless features fidelity field finally finding fine focus frequency frequently function furthermore global good idealized important impractical inaccurate induces inherent inside introduce lack larger linear local localization location long maps metrics minimization minimize modulations mostly near nearly needed noise objective occurs operation opposite optimization optimizing part peak piecewise places principle problems process processing produces proportional proposed quadratic radar radial rapid received regularized related reliable remove removes require resolution resolvable robust roughly segmented service skin smallest smith space spatial spectral spectrum spiral steps straightforward subsequent suffer suggest superior term theory trajectories trajectory transform transformation unreliable usually variations varying wall white whole zero