Simulation of susceptibility-induced distortions in fMRI

Ning Xu; Yong Li; Cynthia B. Paschal; J. Christopher Gatenby; Victoria L. Morgan; David R. Pickens; Benoit M. Dawant; J. Michael Fitzpatrick

doi:10.1117/12.653522

20 March 2006 Simulation of susceptibility-induced distortions in fMRI

Ning Xu, Yong Li, Cynthia B. Paschal, J. Christopher Gatenby, Victoria L. Morgan, David R. Pickens, Benoit M. Dawant, J. Michael Fitzpatrick

Author Affiliations +

Proceedings Volume 6144, Medical Imaging 2006: Image Processing; 61446I (2006) https://doi.org/10.1117/12.653522
Event: Medical Imaging, 2006, San Diego, California, United States

Abstract

It has been recently proposed that computer-simulated phantom images can be used to evaluate methods for fMRI preprocessing. It is widely recognized that Gradient-Echo Echo Planar Imaging (EPI), the most often used technique for fMRI, is strongly affected by field inhomogeneities. Accurate and realistic phantom images for use by the fMRI community for software evaluation and training must incorporate these distortions and account for the effects of head motion and respiration on the distortions. A method to generate realistic distortions caused by field inhomogeneity for the generation of an fMRI phantom is presented in this paper. Changes in field inhomogeneity due to motion are studied by means of adding motions to the brain model and calculating the induced field map numerically rather than measuring it experimentally. A fast analytic version of an MR simulation is used to generate distorted EPI images based on the calculated field maps. The new generated fMRI phantoms can be used to evaluate processing algorithms for fMRI study more accurately. We can appreciate the importance of distortions for fMRI phantom generation by simulating a distortion-free image and adding distortions afterwards. Validations are performed by comparing the calculated field maps with measured ones. In addition, we show the similarities between a simulated fMRI phantom and real EPI image from our MR scanner.

Citation Download Citation

Ning Xu, Yong Li, Cynthia B. Paschal, J. Christopher Gatenby, Victoria L. Morgan, David R. Pickens, Benoit M. Dawant, and J. Michael Fitzpatrick "Simulation of susceptibility-induced distortions in fMRI", Proc. SPIE 6144, Medical Imaging 2006: Image Processing, 61446I (20 March 2006); https://doi.org/10.1117/12.653522

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available