Ghost artifact reduction for echo planar imaging using image phase correction

Michael H. Buonocore, Lisheng Gao

Research output: Contribution to journalArticle

126 Citations (Scopus)

Abstract

An algorithm is described for reducing ghost artifacts in echo planar imaging (EPI) using phase corrections derived from images reconstructed using only even or odd k-space lines. The N/2 ghost, that arises principally from time-reversal of alternate k-space lines, was significantly reduced by this algorithm without the need for a calibration scan. In images obtained in eight subjects undergoing EPI for auditory functional MRI (fMRI) experiments, N/2 ghost intensity was reduced from 10.3% ± 2.1% (range: 7.9-14.1%) to 4.5% ± 0.2% (range: 4.1-4.9%) of parent image intensity, corresponding to a percent reduction in ghost intensity of 54% ± 9% (range: 43-65%), and the algorithm restored this intensity to the parent image. It provided a significant improvement in image appearance, and increased the correlation coefficients related to neural activation in functional MRI studies. The algorithm provided reduction of artifacts from all polynomial orders of spatial phase errors in both spatial directions. The algorithm did not eliminate N/2 ghost intensity contributed by field inhomogeneities, susceptibility, or chemical shift.

Original languageEnglish (US)
Pages (from-to)89-100
Number of pages12
JournalMagnetic Resonance in Medicine
Volume38
Issue number1
DOIs
StatePublished - Jul 1997

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Echo-Planar Imaging
Artifacts
Magnetic Resonance Imaging
Calibration

Keywords

  • Artifacts
  • Echo planar imaging
  • Image processing
  • Magnetic resonance imaging

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Ghost artifact reduction for echo planar imaging using image phase correction. / Buonocore, Michael H.; Gao, Lisheng.

In: Magnetic Resonance in Medicine, Vol. 38, No. 1, 07.1997, p. 89-100.

Research output: Contribution to journalArticle

Buonocore, Michael H. ; Gao, Lisheng. / Ghost artifact reduction for echo planar imaging using image phase correction. In: Magnetic Resonance in Medicine. 1997 ; Vol. 38, No. 1. pp. 89-100.
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