White matter hyperintensity (WMH) shape has been associated with the severity of the underlying brain pathology, suggesting it is a potential neuroimaging marker of WMH impact on brain function.In... Show moreWhite matter hyperintensity (WMH) shape has been associated with the severity of the underlying brain pathology, suggesting it is a potential neuroimaging marker of WMH impact on brain function.In 563 patients with vascular disease (58 +/- 10 years), we examined the relationship between WMH volume, shape, and cognitive functioning. WMH volume and shape were automatically determined on 1.5T brain MRI data. Standardized linear regression analyses estimated the association between WMH volume and shape (concavity index, solidity, convexity, fractal dimension, and eccentricity) and memory and executive functioning, adjusted for age, sex, educational level, and reading ability.Larger WMH volumes were associated with lower executive functioning Z-scores ( b (95%-CI):-0.09 (-0.17;-0.01)). Increased shape complexity of periventricular/confluent WMH associated with lower exec-utive functioning (concavity index + 1SD:-0.13 (-0.20;-0.06); solidity-1SD:-0.09 (-0.17;-0.02)) and lower memory function (fractal dimension + 1SD:-0.10 (-0.18;-0.02)). Of note, the association between concav-ity index and executive functioning was independent of WMH volume (-0.12 (-0.19;-0.04)). Our results suggest that WMH shape contains additional information about WMH burden, not other-wise captured by WMH volume.(c) 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ) Show less
Arterial spin labeling (ASL) has undergone significant development since its inception, with a focus on improving standardization and reproducibility of its acquisition and quantification. In a... Show moreArterial spin labeling (ASL) has undergone significant development since its inception, with a focus on improving standardization and reproducibility of its acquisition and quantification. In a community-wide effort towards robust and reproducible clinical ASL image processing, we developed the software package ExploreASL, allowing standardized analyses across centers and scanners.The procedures used in ExploreASL capitalize on published image processing advancements and address the challenges of multi-center datasets with scanner-specific processing and artifact reduction to limit patient exclusion. ExploreASL is self-contained, written in MATLAB and based on Statistical Parameter Mapping (SPM) and runs on multiple operating systems. To facilitate collaboration and data-exchange, the toolbox follows several standards and recommendations for data structure, provenance, and best analysis practice.ExploreASL was iteratively refined and tested in the analysis of >10,000 ASL scans using different pulse-sequences in a variety of clinical populations, resulting in four processing modules: Import, Structural, ASL, and Population that perform tasks, respectively, for data curation, structural and ASL image processing and quality control, and finally preparing the results for statistical analyses on both single-subject and group level. We illustrate ExploreASL processing results from three cohorts: perinatally HIV-infected children, healthy adults, and elderly at risk for neurodegenerative disease. We show the reproducibility for each cohort when processed at different centers with different operating systems and MATLAB versions, and its effects on the quantification of gray matter cerebral blood flow.ExploreASL facilitates the standardization of image processing and quality control, allowing the pooling of cohorts which may increase statistical power and discover between-group perfusion differences. Ultimately, this workflow may advance ASL for wider adoption in clinical studies, trials, and practice. Show less
Odish, O.; Leemans, A.; Reijntjes, R.; Bogaard, S. van den; Dumas, E.; Wolterbeek, R.; ... ; Roos, R.A.C. 2014
