Local Diffusion Homogeneity Provides Supplementary Information in T2DM-Related WM Microstructural Abnormality Detection

Abstract

Objectives: We aimed to investigate whether an inter-voxel diffusivity metric (local diffusion homogeneity, LDH), can provide supplementary information to traditional intra-voxel metrics (i.e., fractional anisotropy, FA) in white matter (WM) abnormality detection for type 2 diabetes mellitus (T2DM).Methods: Diffusion tensor imaging was acquired from 34 T2DM patients and 32 healthy controls. Voxel-based group-difference comparisons based on LDH and FA, as well as the association between the diffusion metrics and T2DM risk factors [i.e., body mass index (BMI) and systolic blood pressure (SBP)], were conducted, with age, gender and education level controlled.Results: Compared to the controls, T2DM patients had higher LDH in the pons and left temporal pole, as well as lower FA in the left superior corona radiation (p < 0.05, corrected). In T2DM, there were several overlapping WM areas associated with BMI as revealed by both LDH and FA, including right temporal lobe and left inferior parietal lobe; but the unique areas revealed only by using LDH included left inferior temporal lobe, right supramarginal gyrus, left pre- and post-central gyrus (at the semiovale center), and right superior radiation. Overlapping WM areas that associated with SBP were found with both LDH and FA, including right temporal pole, bilateral orbitofrontal area (rectus gyrus), the media cingulum bundle, and the right cerebellum crus I. However, the unique areas revealed only by LDH included right inferior temporal lobe, right inferior occipital lobe, and splenium of corpus callosum.Conclusion: Inter- and intra-voxel diffusivity metrics may have different sensitivity in the detection of T2DM-related WM abnormality. We suggested that LDH could provide supplementary information and reveal additional underlying brain changes due to diabetes.

Assessment of Lactate Dehydrogenase Levels Among Diabetic Patients Treated in the Outpatient Clinics at King Hussein Medical Center, Royal Medical Services, Jordan

“…Increased level of LDH, as mentioned earlier, reflects the adverse effects of diabetes. The association between LDH and BMI among diabetic patients in our study is in line with other studies ( 15 - 17 ).…”

Altered Functional Hubs and Connectivity in Type 2 Diabetes Mellitus Without Mild Cognitive Impairment

“…Higher FCs indicate the enhancement of temporal consistency of the different brain regions. In the present study, increased FC based on the hub DC analysis was found not only within different cerebellar regions but also between ipsilateral cerebrocerebellar regions, suggesting sophisticated recruitment capacity of the cerebellum in T2DM (15,42,43). Though the cognitive functions of the cerebellum are not yet well-understood, a study based on exceptionally large and high-quality dataset analysis indicated that functional gradients of the cerebellum correspond to intrinsic connectivity of cerebellar voxels with the rest of the cerebellum (49).…”

“…However, some previous studies reported that T2DM subjects showed significant decreased anatomical connections, mean regional homogeneity (mReHo), cerebral blood flow (CBF), and DC in cerebellar regions ( 46 – 48 ), providing evidence to the significant role of the cerebellum in terms of cognitive function. Although inconsistent results were obtained, it is believed that the cerebellum might play an important role in maintaining normal cognitive functions in T2DM before the onset of symptoms or even at the prediabetic stage ( 15 , 43 ).…”

“…Scanning consisted of two parts: conventional sequences were used for screening lesions, and functional sequences were used for experiment processing. First, all participants underwent conventional brain axial T1-weighted, T2-weighted, and fluid-attenuated inversion recovery (FLAIR) images to rule out brain organic diseases and white matter hyperintensity (WMH) lesions ( 15 ). Images of conventional sequences (T1, T2, and FLAIR) were inspected, respectively, by two radiologists who had a wealth of work experience, and none of the subjects were excluded after the conventional scans.…”

“…However, results of the region of interest (ROI)-based FC analysis should be interpreted in caution, as the selected ROIs are mainly based on the prior knowledge, leading to different and unpredictable findings ( 13 ). Our previous studies showed microstructure of the white matter changes in T2DM without MCI in several brain regions including the bilateral cingulum lobe and thalami ( 14 ), pons, and left temporal pole ( 15 ). It is believed that alterations in brain structure may lead to changes in brain function ( 16 – 19 ).…”