eprintid: 10049420 rev_number: 18 eprint_status: archive userid: 608 dir: disk0/10/04/94/20 datestamp: 2018-05-29 13:29:04 lastmod: 2021-10-14 23:01:40 status_changed: 2018-05-29 13:29:04 type: article metadata_visibility: show creators_name: David, G creators_name: Freund, P creators_name: Mohammadi, S title: The efficiency of retrospective artifact correction methods in improving the statistical power of between-group differences in spinal cord DTI ispublished: pub divisions: UCL divisions: B02 divisions: C07 divisions: D07 divisions: F85 keywords: Science & Technology, Life Sciences & Biomedicine, Neurosciences, Neuroimaging, Radiology, Nuclear Medicine & Medical Imaging, Neurosciences & Neurology, DIFFUSION-WEIGHTED MRI, WHITE-MATTER PATHOLOGY, IN-VIVO, MULTIPLE-SCLEROSIS, ROBUST ESTIMATION, EDDY-CURRENT, OPTIC-NERVE, GRAY-MATTER, HUMAN BRAIN, TENSOR note: This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ abstract: Diffusion tensor imaging (DTI) is a promising approach for investigating the white matter microstructure of the spinal cord. However, it suffers from severe susceptibility, physiological, and instrumental artifacts present in the cord. Retrospective correction techniques are popular approaches to reduce these artifacts, because they are widely applicable and do not increase scan time. In this paper, we present a novel outlier rejection approach (reliability masking) which is designed to supplement existing correction approaches by excluding irreversibly corrupted and thus unreliable data points from the DTI index maps. Then, we investigate how chains of retrospective correction techniques including (i) registration, (ii) registration and robust fitting, and (iii) registration, robust fitting, and reliability masking affect the statistical power of a previously reported finding of lower fractional anisotropy values in the posterior column and lateral corticospinal tracts in cervical spondylotic myelopathy (CSM) patients. While established post-processing steps had small effect on the statistical power of the clinical finding (slice-wise registration: −0.5%, robust fitting: +0.6%), adding reliability masking to the post-processing chain increased it by 4.7%. Interestingly, reliability masking and registration affected the t-score metric differently: while the gain in statistical power due to reliability masking was mainly driven by decreased variability in both groups, registration slightly increased variability. In conclusion, reliability masking is particularly attractive for neuroscience and clinical research studies, as it increases statistical power by reducing group variability and thus provides a cost-efficient alternative to increasing the group size. date: 2017-06-29 date_type: published publisher: ACADEMIC PRESS INC ELSEVIER SCIENCE official_url: https://doi.org/10.1016/j.neuroimage.2017.06.051 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green article_type_text: Article verified: verified_manual elements_id: 1302557 doi: 10.1016/j.neuroimage.2017.06.051 lyricists_name: Freund, Patrick lyricists_id: PFREU62 actors_name: Stacey, Thomas actors_id: TSSTA20 actors_role: owner full_text_status: public publication: NeuroImage volume: 158 pagerange: 296-307 pages: 12 issn: 1095-9572 citation: David, G; Freund, P; Mohammadi, S; (2017) The efficiency of retrospective artifact correction methods in improving the statistical power of between-group differences in spinal cord DTI. NeuroImage , 158 pp. 296-307. 10.1016/j.neuroimage.2017.06.051 <https://doi.org/10.1016/j.neuroimage.2017.06.051>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10049420/1/1-s2.0-S1053811917305220-main.pdf