@article {2235, title = {Improved diffusion parameter estimation by incorporating T2 relaxation properties into the DKI-FWE model}, journal = {NeuroImage}, volume = {256}, year = {2022}, pages = {119219}, doi = {https://doi.org/10.1016/j.neuroimage.2022.119219}, author = {Vincenzo Anania and Quinten Collier and Jelle Veraart and Annemieke Eline Buikema and Floris Vanhevel and Thibo Billiet and Ben Jeurissen and Arnold Jan den Dekker and Jan Sijbers} } @article {1820, title = {Diffusion kurtosis imaging with free water elimination: a Bayesian estimation approach}, journal = {Magnetic Resonance in Medicine}, volume = {80}, year = {2018}, pages = {802-813}, doi = {10.1002/mrm.27075}, author = {Quinten Collier and Jelle Veraart and Ben Jeurissen and Floris Vanhevel and Pim Pullens and Paul M Parizel and Arnold Jan den Dekker and Jan Sijbers} } @mastersthesis {1911, title = {Robust estimation of diffusion tensor and diffusion kurtosis imaging parameters}, volume = {PhD in Sciences/Physics}, year = {2018}, month = {Oct/2018}, school = {University of Antwerp}, type = {PhD thesis}, address = {Antwerp}, author = {Quinten Collier} } @article {1824, title = {White matter microstructural organization of interhemispheric pathways predicts different stages of bimanual coordination learning in young and older adults}, journal = {European Journal of Neuroscience }, volume = {47}, year = {2018}, pages = {446{\textendash}459}, doi = {10.1111/ejn.13841}, author = {Hamed Zivari Adab and Sima Chalavi and Iseult Beets and Jolien Gooijers and Inge Leunissen and Boris Cheval and Quinten Collier and Jan Sijbers and Ben Jeurissen and S. P. Swinnen and Matthieu Boisgontier} } @conference {1764, title = {Solving the Free Water Elimination Estimation Problem by Incorporating T2 Relaxation Properties}, year = {2017}, author = {Quinten Collier and Jelle Veraart and Arnold Jan den Dekker and Floris Vanhevel and Paul M Parizel and Jan Sijbers} } @conference {1672, title = {Robust DKI parameter estimation in case of CSF partial volume effects}, year = {2016}, abstract = {Diffusion kurtosis imaging (DKI) suffers from partial volume effects caused by cerebrospinal fluid (CSF). We propose a DKI+CSF model combined with a framework to robustly estimate the DKI parameters. Since the estimation problem is ill-conditioned, a Bayesian estimation approach with a shrinkage prior is incorporated. Both simulation and real data experiments suggest that the use of this prior leads to a more accurate, precise and robust estimation of the DKI+CSF model parameters. Finally, we show that not correcting for the CSF compartment can lead to severe biases in the parameter estimations.}, author = {Quinten Collier and Arnold Jan den Dekker and Ben Jeurissen and Jan Sijbers} } @conference {1671, title = {A robust framework for combined estimation of DKI and CSF partial volume fraction parameters}, year = {2016}, abstract = {Diffusion kurtosis imaging (DKI) suffers from partial volume effects caused by cerebrospinal fluid (CSF). We propose a DKI+CSF model combined with a framework to robustly estimate the DKI parameters. Since the estimation problem is ill-conditioned, a Bayesian estimation approach with a shrinkage prior is incorporated. Both simulation and real data experiments suggest that the use of this prior leads to a more accurate, precise and robust estimation of the DKI+CSF model parameters. Finally, we show that not correcting for the CSF compartment can lead to severe biases in the parameter estimations.}, author = {Quinten Collier and Arnold Jan den Dekker and Ben Jeurissen and Jan Sijbers} } @conference {1624, title = {CSF partial volume modeling in diffusion kurtosis imaging: a comparative parameter estimation study}, year = {2015}, month = {11/2015}, doi = {10.3389/conf.fninf.2015.19.00039}, url = {http://www.frontiersin.org/myfrontiers/events/abstractdetails.aspx?abs_doi=10.3389/conf.fninf.2015.19.00039}, author = {Quinten Collier and Jelle Veraart and Arnold Jan den Dekker and Ben Jeurissen and Jan Sijbers} } @article {1492, title = {Iterative Reweighted Linear Least Squares for Accurate, Fast, and Robust Estimation of Diffusion Magnetic Resonance Parameters}, journal = {Magnetic Resonance in Medicine}, volume = {73}, year = {2015}, pages = {2174{\textendash}2184}, abstract = {Purpose: Diffusion-weighted magnetic resonance imaging suffers from physiological noise, such as artifacts caused by motion or system instabilities. Therefore, there is a need for robust diffusion parameter estimation techniques. In the past, several techniques have been proposed, including RESTORE and iRESTORE. However, these techniques are based on nonlinear estimators and are consequently computationally intensive. Method: In this work, we present a new, robust, iteratively reweighted linear least squares (IRLLS) estimator. IRLLS performs a voxel-wise identification of outliers in diffusion-weighted magnetic resonance images, where it exploits the natural skewness of the data distribution to become more sensitive to both signal hyperintensities and signal dropouts. Results: Both simulations and real data experiments were conducted to compare IRLLS with other state-of-the-art techniques. While IRLLS showed no significant loss in accuracy or precision, it proved to be substantially faster than both RESTORE and iRESTORE. In addition, IRLLS proved to be even more robust when considering the overestimation of the noise level or when the signal-to-noise ratio is low. Conclusion: The substantially shortened calculation time in combination with the increased robustness and accuracy, make IRLLS a practical and reliable alternative to current state-of-theart techniques for the robust estimation of diffusion-weighted magnetic resonance parameters.}, keywords = {diffusion tensor imaging, MRI, outlier detection, robust, weighted linear least squares}, doi = {10.1002/mrm.25351}, author = {Quinten Collier and Jelle Veraart and Ben Jeurissen and Arnold Jan den Dekker and Jan Sijbers} } @conference {1544, title = {Theoretical study of the free water elimination model}, year = {2015}, pages = {78}, abstract = {Partial volume effects caused by cerebrospinal fluid are an important issue in diffusion MRI. In this work, we study the free water elimination model by analyzing the Cram{\'e}r-Rao lower bound (CRLB) of its parameters. We show that through optimizing the acquisition protocol by minimizing the trace of the CRLB, a significant gain in the precision of the parameter estimation can be achieved. Moreover, further analysis indicates that regularization and/or constraints are necessary for parameter estimation from voxels with large CSF fractions and/or low FA values. These theoretical findings are confirmed by both simulation and real data experiments.}, author = {Quinten Collier and Jelle Veraart and Ben Jeurissen and Arnold Jan den Dekker and Jan Sijbers} } @conference {1545, title = {Theoretical study of the free water elimination model}, volume = {23}, year = {2015}, pages = {2757}, abstract = {Partial volume effects caused by cerebrospinal fluid are an important issue in diffusion MRI. In this work, we study the free water elimination model by analyzing the Cram{\'e}r-Rao lower bound (CRLB) of its parameters. We show that through optimizing the acquisition protocol by minimizing the trace of the CRLB, a significant gain in the precision of the parameter estimation can be achieved. Moreover, further analysis indicates that regularization and/or constraints are necessary for parameter estimation from voxels with large CSF fractions and/or low FA values. These theoretical findings are confirmed by both simulation and real data experiments.}, author = {Quinten Collier and Jelle Veraart and Ben Jeurissen and Arnold Jan den Dekker and Jan Sijbers} } @conference {1426, title = {Iterative reweighted linear least squares for the accurate, fast, and robust estimation of diffusion magnetic resonance parameters}, year = {2013}, author = {Quinten Collier and Jelle Veraart and Jan Sijbers} } @conference {1366, title = {Discrete algebraic reconstruction in MRI: a simulation study}, volume = {25}, year = {2012}, pages = {480-481}, keywords = {compressed sensing, DART, iterative reconstruction, prior knowledge}, doi = {10.1007/s10334-012-0324-9}, author = {Quinten Collier and Segers, Hilde and Jan Sijbers} }