Fast autofocusing of motion-corrupted MR images using one-dimensional Fourier transforms

Research output: Chapter in Book/Report/Conference proceedingConference contribution

3 Citations (Scopus)

Abstract

In most clinical MR images, global patient motion is predominantly interview (between readouts), and corrupts the phase of the received signal for that line of k-space. No information, however, is lost - if the original motion is known and appropriate phase corrections applied, the image can be perfectly restored. It is therefore possible to correct for motion given only the real and imaginary data from the scanner by simply trying different possible motion corrections and searching for the highest quality resulting image with a suitable evaluation function. Such an 'autofocusing' algorithm was recently described, using image entropy as the cost function; however, very long computation times are required. If the corrupting motion is primarily 1D, much faster autofocusing might be possible by calculating only selected lines of the image. In this paper, we describe work on such an algorithm, implemented with both minimum entropy and maximum variance as the cost functions. Tests on several 256 X 256 magnitude images artificially corrupted by 1D motion indicate that evaluating only eight selected columns of the image (calculated with eight 1D FFT's) works very well - essentially as well as evaluating the whole image, which requires 2D FFT's. The run time dropped from several hours for 2D FFT's to less than ten minutes using 1D FFT's. One test image with little dark area was not well corrected, indicating the possible dependence of both cost functions on dark regions to be cleared of artifacts.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
Pages391-397
Number of pages7
Volume3338
DOIs
StatePublished - 1998
EventMedical Imaging 1998: Image Processing - San Diego, CA, United States
Duration: Feb 23 1998Feb 23 1998

Other

OtherMedical Imaging 1998: Image Processing
CountryUnited States
CitySan Diego, CA
Period2/23/982/23/98

Fingerprint

Auto-focusing
Fast Fourier transforms
Fourier transform
Fourier transforms
Cost functions
Motion
fast Fourier transformations
Entropy
Cost Function
Function evaluation
Image quality
costs
entropy
K-space
Line
Evaluation Function
Scanner
Image Quality
scanners
readout

Keywords

  • Autofocusing
  • Image processing
  • Motion correction
  • MRI
  • Navigator echoes

ASJC Scopus subject areas

  • Applied Mathematics
  • Computer Science Applications
  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Welch, E. B., Manduca, A., & Ehman, R. L. (1998). Fast autofocusing of motion-corrupted MR images using one-dimensional Fourier transforms. In Proceedings of SPIE - The International Society for Optical Engineering (Vol. 3338, pp. 391-397) https://doi.org/10.1117/12.310917

Fast autofocusing of motion-corrupted MR images using one-dimensional Fourier transforms. / Welch, Edward Brian; Manduca, Armando; Ehman, Richard Lorne.

Proceedings of SPIE - The International Society for Optical Engineering. Vol. 3338 1998. p. 391-397.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Welch, EB, Manduca, A & Ehman, RL 1998, Fast autofocusing of motion-corrupted MR images using one-dimensional Fourier transforms. in Proceedings of SPIE - The International Society for Optical Engineering. vol. 3338, pp. 391-397, Medical Imaging 1998: Image Processing, San Diego, CA, United States, 2/23/98. https://doi.org/10.1117/12.310917
Welch EB, Manduca A, Ehman RL. Fast autofocusing of motion-corrupted MR images using one-dimensional Fourier transforms. In Proceedings of SPIE - The International Society for Optical Engineering. Vol. 3338. 1998. p. 391-397 https://doi.org/10.1117/12.310917
Welch, Edward Brian ; Manduca, Armando ; Ehman, Richard Lorne. / Fast autofocusing of motion-corrupted MR images using one-dimensional Fourier transforms. Proceedings of SPIE - The International Society for Optical Engineering. Vol. 3338 1998. pp. 391-397
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