Investigating the prevalence of complex fiber configurations in white matter tissue with diffusion magnetic resonance imaging

• Published in: Human brain mapping Vol. 34; no. 11; pp. 2747 - 2766
• Main Authors: Jeurissen, Ben, Leemans, Alexander, Tournier, Jacques-Donald, Jones, Derek K., Sijbers, Jan
• Format: Journal Article
• Language: English
• Published: New York, NY Blackwell Publishing Ltd 01.11.2013; Wiley-Liss; John Wiley & Sons, Inc; John Wiley and Sons Inc
• Subjects: Adult; Algorithms; Anisotropy; bedpostx; Biological and medical sciences; Brain - anatomy & histology; Brain Mapping; constrained spherical deconvolution; crossing fibers; Data Interpretation, Statistical; Diffusion Magnetic Resonance Imaging - methods; Excitatory Postsynaptic Potentials; False Positive Reactions; Fundamental and applied biological sciences. Psychology; high-angular resolution diffusion imaging; Humans; Image Processing, Computer-Assisted - methods; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Nerve Fibers - physiology; Nervous system; partial volume effect; Perception; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Reproducibility of Results; residual bootstrap; Signal-To-Noise Ratio; Vision; white matter; High resolution; Nervous system diseases; Prevalence; Configuration; Radiodiagnosis; crossing fibers; Diffusion imaging; partial volume effect; Nuclear magnetic resonance imaging; White matter; constrained spherical deconvolution; residual bootstrap; Bootstrap; bedpostx; high-angular resolution diffusion imaging; white matter
• ISSN: 1065-9471; 1097-0193
• DOI: 10.1002/hbm.22099

It has long been recognized that the diffusion tensor model is inappropriate to characterize complex fiber architecture, causing tensor‐derived measures such as the primary eigenvector and fractional anisotropy to be unreliable or misleading in these regions. There is however still debate about the impact of this problem in practice. A recent study using a Bayesian automatic relevance detection (ARD) multicompartment model suggested that a third of white matter (WM) voxels contain crossing fibers, a value that, whilst already significant, is likely to be an underestimate. The aim of this study is to provide more robust estimates of the proportion of affected voxels, the number of fiber orientations within each WM voxel, and the impact on tensor‐derived analyses, using large, high‐quality diffusion‐weighted data sets, with reconstruction parameters optimized specifically for this task. Two reconstruction algorithms were used: constrained spherical deconvolution (CSD), and the ARD method used in the previous study. We estimate the proportion of WM voxels containing crossing fibers to be ∼90% (using CSD) and 63% (using ARD). Both these values are much higher than previously reported, strongly suggesting that the diffusion tensor model is inadequate in the vast majority of WM regions. This has serious implications for downstream processing applications that depend on this model, particularly tractography, and the interpretation of anisotropy and radial/axial diffusivity measures. Hum Brain Mapp 34:2747–2766, 2013. © 2012 Wiley Periodicals, Inc.