Fiber orientation distribution from diffusion MRI: Effects of inaccurate response function calibration. Issue 6 (15th June 2021)

• Record Type: Journal Article
• Authors: Guo, Fenghua; Tax, Chantal M. W.; De Luca, Alberto; Viergever, Max A.; Heemskerk, Anneriet; Leemans, Alexander
• Is Part Of: Journal of neuroimaging. Volume 31:Issue 6(2021)
• Page Start: 1082
• Page End: 1098
• Publication Date: 2021-06-15
• Subjects: apparent fiber density (AFD) -- constrained spherical deconvolution (CSD) -- diffusion MRI -- fiber orientation distribution (FOD) -- fiber tractography; Diagnostic imaging -- Periodicals; Nervous system -- Diseases -- Diagnosis -- Periodicals; Imagerie pour le diagnostic -- Périodiques; Système nerveux -- Maladies -- Diagnostic -- Périodiques; Imagerie médicale; Neuroimagerie; Neurologie; Système nerveux; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.804754
• DOI: 10.1111/jon.12901
• Languages: English
• ISSNs: 1051-2284

Abstract

ABSTRACT: Background and Purpose: Diffusion MRI of the brain enables to quantify white matter fiber orientations noninvasively. Several approaches have been proposed to estimate such characteristics from diffusion MRI data with spherical deconvolution being one of the most widely used methods. Spherical deconvolution requires to define––or derive from the data––a response function, which is used to compute the fiber orientation distribution (FOD). Different characteristics of the response function are expected to affect the FOD computation and the subsequent fiber tracking. Methods: In this work, we explored the effects of inaccuracies in the shape factors of the response function on the FOD characteristics. Results: With simulations, we show that the apparent fiber density could be doubled in the presence of underestimated shape factors in the response functions, whereas the overestimation of the shape factor will cause more spurious peaks in the FOD, especially when the signal‐to‐noise ratio is below 15. Moreover, crossing fiber populations with a separation angle smaller than 60° were more sensitive to inaccuracies in the response function than fiber populations with more orthogonal separation angles. Results with in vivo data demonstrate angular deviations in the FODs and spurious peaks as a result of modified shape factors of the response function, while the reconstruction of the main parts of fiber bundles is well preserved. Conclusions: This work sheds light on how specific aspects of the response function shape can affect the estimated FODs, and highlights the importance of a proper calibration/definition of the response function.