title: A method for handling intensity inhomogenieties in fMRI sequences of moving anatomy of the early developing brain.
abstract: This paper presents a method for intensity inhomogeniety removal in fMRI studies of a moving subject. In such studies, subtle changes in signal as the subject moves in the presence of a bias field can be a significant confound for BOLD signal analysis. The proposed method avoids the need for a specific tissue model or assumptions about tissue homogeneity by making use of the multiple views of the underlying bias field provided by the subject's motion. A parametric bias field model is assumed and a regression model is used to estimate the basis function weights of this model. Quantitative evaluation of the effects of motion and noise in motion estimates are performed using simulated data. Results demonstrate the strength and robustness of the new method compared to the state of the art 4D nonparametric bias estimator (N4ITK). We also qualitatively demonstrate the impact of the method on resting state neuroimage analysis of a moving adult brain with simulated motion and bias fields, as well as on in vivo moving fetal fMRI.
authors: Biomedical Image Computing Group, Departments of Pediatrics, Bioengineering, and Radiology, University of Washington, Seattle, WA 98195, USA. Electronic address: seshaman@uw.edu.
authors: Sharmishtaa
authors: S
authors: Seshamani
authors: Biomedical Image Computing Group, Departments of Pediatrics, Bioengineering, and Radiology, University of Washington, Seattle, WA 98195, USA.
authors: Xi
authors: X
authors: Cheng
authors: Biomedical Image Computing Group, Departments of Pediatrics, Bioengineering, and Radiology, University of Washington, Seattle, WA 98195, USA.
authors: Mads
authors: M
authors: Fogtmann
authors: Merrill Palmer Skillman Institute for Child and Family Development, Wayne State University, Detroit, MI, USA; Department of Pediatrics, Wayne State University School of Medicine, Detroit, MI, USA; Perinatology Research Branch, NICHD/NIH/DHHS, Detroit, MI, USA.
authors: Moriah E
authors: ME
authors: Thomason
authors: Biomedical Image Computing Group, Departments of Pediatrics, Bioengineering, and Radiology, University of Washington, Seattle, WA 98195, USA.
authors: Colin
authors: C
authors: Studholme
mesh_terms: D000328:Adult; D000465:Algorithms; D016477:Artifacts; D001921:Brain / Q000196:embryology / Q000254:growth & development*; D001931:Brain Mapping / Q000379:methods*; D003198:Computer Simulation; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011247:Pregnancy; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Bias correction; FMRI; Fetal imaging