Associations Between Microstructure, White Matter Hyperintensity Severity, and Cognitive Impairment: An Intravoxel Incoherent Motion Study

Motivation: It is still unclear what the mechanism of the effect of white matter hyperintensities (WMHs) and cognitive impairment is. Goal(s): To use intravoxel incoherent motion (IVIM) to evaluate the microvascular and parenchymal microstructural changes of WMHs and to investigate their association with cognitive impairment. Approach: The IVIM parameters were compared between patients and controls, different ROIs, and different WMH severity. Additionally, a multivariate linear regression analysis was conducted to explore the factors influencing cognitive scores. Results: WMH patients had higher parenchymal diffusivity than the control group. Furthermore, increased parenchymal diffusivity was associated with an increased risk of cognitive decline. Impact: The IVIM technique has the potential to provide a quantitative marker of parenchymal diffusivity for assessing the severity of WMH and may be useful in quantifying cognitive dysfunction in patients with WMH.