Diffusion tensor imaging of brain white matter in Huntington gene mutation individuals

ABSTRACT Objective To evaluate the role of the involvement of white matter tracts in huntingtin gene mutation patients as a potential biomarker of the progression of the disease. Methods We evaluated 34 participants (11 symptomatic huntingtin gene mutation, 12 presymptomatic huntingtin gene mutation, and 11 controls). We performed brain magnetic resonance imaging to assess white matter integrity using diffusion tensor imaging, with measurement of fractional anisotropy. Results We observed a significant decrease of fractional anisotropy in the cortical spinal tracts, corona radiate, corpus callosum, external capsule, thalamic radiations, superior and inferior longitudinal fasciculus, and inferior frontal-occipital fasciculus in the Huntington disease group compared to the control and presymptomatic groups. Reduction of fractional anisotropy is indicative of a degenerative process and axonal loss. There was no statistically significant difference between the presymptomatic and control groups. Conclusion White matter integrity is affected in huntingtin gene mutation symptomatic individuals, but other studies with larger samples are required to assess its usefulness in the progression of the neurodegenerative process.

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Diffusion tensor imaging analysis in scrub typhus meningoencephalitis to determine the alteration of microstructural subcortical white-matter integrity

The Neuroradiology Journal ◽

10.1177/1971400920980311 ◽

2020 ◽

pp. 197140092098031

Author(s):

Pranjal Phukan ◽

Kalyan Sarma ◽

Aman Yusuf Khan ◽

Bhupen Barman ◽

Md Jamil ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Scrub Typhus ◽

Diffusion Tensor ◽

Neuronal Degeneration ◽

Central Nervous System Involvement ◽

Subcortical White Matter ◽

White Matter Integrity ◽

Conventional Mri ◽

Significant Difference

Background and purpose Magnetic resonance imaging (MRI) of the brain in scrub typhus meningoencephalitis is non-specific, and in the majority of the cases, conventional MRI fails to detect any abnormality. However, autopsy reports depict central nervous system involvement in almost all patients. There is therefore a need for research on the quantitative assessment of brain parenchyma that can detect microstructural abnormalities. The study aimed to assess the microstructural integrity changes of scrub typhus meningoencephalitis by using different diffusion tensor imaging (DTI) parameters. Methods This was a retrospective analysis of scrub typhus meningoencephalitis. Seven patients and seven age- and sex-matched healthy controls were included. Different DTI parameters such as apparent diffusion coefficient (ADC), fractional anisotropy (FA), relative anisotropy (RA), trace, volume ratio (VR) and geodesic anisotropy (GA) were obtained from six different regions of subcortical white matter at the level of the centrum semiovale. Intergroup significant difference was determined by one-way analysis of variance followed by Tukey’s post hoc test. Receiver operating characteristic curves were constructed to determine the accuracy of the DTI matrices. Results There was a significant decrease in FA, RA and GA as well as an increase in ADC and VR in the subcortical white matter in patients with scrub typhus meningoencephalitis compared to controls ( p < 0.001). The maximum sensitivity of the DTI parameters was 85.7%, and the maximum specificity was 81%. Conclusion There was an alteration of subcortical white-matter integrity in scrub typhus meningoencephalitis that represents the axonal degeneration, myelin breakdown and neuronal degeneration. DTI may be a useful tool to detect white-matter abnormalities in scrub typhus meningoencephalitis in clinical practice, particularly in patients with negative conventional MRI.

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Consistency of Fractional Anisotropy Values Using Different Combinations of b-Value and Time of Echo (TE) in Diffusion Tensor Imaging of Normal Brain White Matter

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2018/38089.12315 ◽

2018 ◽

Author(s):

Rahul P Kotian ◽

K Prakashini ◽

Sreekumaran Nair ◽

M Satish Babu

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Fractional Anisotropy ◽

Diffusion Tensor ◽

B Value ◽

Normal Brain ◽

Brain White Matter

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White Matter Integrity Predicts Delay Discounting Behavior in 9- to 23-Year-Olds: A Diffusion Tensor Imaging Study

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2009.21107 ◽

2009 ◽

Vol 21 (7) ◽

pp. 1406-1421 ◽

Cited By ~ 119

Author(s):

Elizabeth A. Olson ◽

Paul F. Collins ◽

Catalina J. Hooper ◽

Ryan Muetzel ◽

Kelvin O. Lim ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Delay Discounting ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Imaging Study ◽

Temporal Lobes ◽

Brain White Matter ◽

Independent Effects ◽

Age Range

Healthy participants (n = 79), ages 9–23, completed a delay discounting task assessing the extent to which the value of a monetary reward declines as the delay to its receipt increases. Diffusion tensor imaging (DTI) was used to evaluate how individual differences in delay discounting relate to variation in fractional anisotropy (FA) and mean diffusivity (MD) within whole-brain white matter using voxel-based regressions. Given that rapid prefrontal lobe development is occurring during this age range and that functional imaging studies have implicated the prefrontal cortex in discounting behavior, we hypothesized that differences in FA and MD would be associated with alterations in the discounting rate. The analyses revealed a number of clusters where less impulsive performance on the delay discounting task was associated with higher FA and lower MD. The clusters were located primarily in bilateral frontal and temporal lobes and were localized within white matter tracts, including portions of the inferior and superior longitudinal fasciculi, anterior thalamic radiation, uncinate fasciculus, inferior fronto-occipital fasciculus, corticospinal tract, and splenium of the corpus callosum. FA increased and MD decreased with age in the majority of these regions. Some, but not all, of the discounting/DTI associations remained significant after controlling for age. Findings are discussed in terms of both developmental and age-independent effects of white matter organization on discounting behavior.

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Quantitative diffusion tensor imaging analysis does not distinguish pediatric canines with mucopolysaccharidosis I from control canines

The Neuroradiology Journal ◽

10.1177/1971400917718844 ◽

2017 ◽

Vol 30 (5) ◽

pp. 454-460

Author(s):

Dana M Middleton ◽

Jonathan Y Li ◽

Steven D Chen ◽

Leonard E White ◽

Patricia I Dickson ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Fractional Anisotropy ◽

Imaging System ◽

Diffusion Tensor ◽

Brain Regions ◽

Magnetic Resonance Imaging System ◽

Radial Diffusivity ◽

Mucopolysaccharidosis I ◽

Diffusivity Measurements

Purpose We compared fractional anisotropy and radial diffusivity measurements between pediatric canines affected with mucopolysaccharidosis I and pediatric control canines. We hypothesized that lower fractional anisotropy and higher radial diffusivity values, consistent with dysmyelination, would be present in the mucopolysaccharidosis I cohort. Methods Six canine brains, three affected with mucopolysaccharidosis I and three unaffected, were euthanized at 7 weeks and imaged using a 7T small-animal magnetic resonance imaging system. Average fractional anisotropy and radial diffusivity values were calculated for four white-matter regions based on 100 regions of interest per region per specimen. A 95% confidence interval was calculated for each mean value. Results No difference was seen in fractional anisotropy or radial diffusivity values between mucopolysaccharidosis affected and unaffected brains in any region. In particular, the 95% confidence intervals for mucopolysaccharidosis affected and unaffected canines frequently overlapped for both fractional anisotropy and radial diffusivity measurements. In addition, in some brain regions a large range of fractional anisotropy and radial diffusivity values were seen within the same cohort. Conclusion The fractional anisotropy and radial diffusivity values of white matter did not differ between pediatric mucopolysaccharidosis affected canines and pediatric control canines. Possible explanations include: (a) a lack of white matter tissue differences between mucopolysaccharidosis affected and unaffected brains at early disease stages; (b) diffusion tensor imaging does not detect any existing differences; (c) inflammatory processes such as astrogliosis produce changes that offset the decreased fractional anisotropy values and increased radial diffusivity values that are expected in dysmyelination; and (d) our sample size was insufficient to detect differences. Further studies correlating diffusion tensor imaging findings to histology are warranted.

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Age-related changes in white matter integrity: A diffusion tensor imaging study

NeuroImage ◽

10.1016/s1053-8119(09)71239-x ◽

2009 ◽

Vol 47 ◽

pp. S128

Author(s):

H Lemaitre ◽

S Marenco ◽

M Emery ◽

T Alam ◽

M Geramita ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Diffusion Tensor ◽

Imaging Study ◽

White Matter Integrity ◽

Age Related ◽

Diffusion Tensor Imaging Study ◽

Age Related Changes

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Age-related differences in multiple measures of white matter integrity: A diffusion tensor imaging study of healthy aging

Human Brain Mapping ◽

10.1002/hbm.20872 ◽

2009 ◽

pp. NA-NA ◽

Cited By ~ 67

Author(s):

Ilana J. Bennett ◽

David J. Madden ◽

Chandan J. Vaidya ◽

Darlene V. Howard ◽

James H. Howard

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Healthy Aging ◽

Diffusion Tensor ◽

Imaging Study ◽

White Matter Integrity ◽

Multiple Measures ◽

Age Related ◽

Diffusion Tensor Imaging Study

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Olfactory Function and Diffusion Tensor Imaging as Markers of Mild Cognitive Impairment in Early Stages of Parkinson's Disease

Clinical EEG and Neuroscience ◽

10.1177/15500594211058263 ◽

2021 ◽

pp. 155005942110582

Author(s):

Sophie A. Stewart ◽

Laura Pimer ◽

John D. Fisk ◽

Benjamin Rusak ◽

Ron A. Leslie ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cognitive Impairment ◽

Diffusion Tensor Imaging ◽

Mild Cognitive Impairment ◽

White Matter ◽

Neurodegenerative Disorder ◽

Diffusion Tensor ◽

Early Stage ◽

White Matter Integrity

Parkinson's disease (PD) is a neurodegenerative disorder that is typified by motor signs and symptoms but can also lead to significant cognitive impairment and dementia Parkinson's Disease Dementia (PDD). While dementia is considered a nonmotor feature of PD that typically occurs later, individuals with PD may experience mild cognitive impairment (PD-MCI) earlier in the disease course. Olfactory deficit (OD) is considered another nonmotor symptom of PD and often presents even before the motor signs and diagnosis of PD. We examined potential links among cognitive impairment, olfactory functioning, and white matter integrity of olfactory brain regions in persons with early-stage PD. Cognitive tests were used to established groups with PD-MCI and with normal cognition (PD-NC). Olfactory functioning was examined using the University of Pennsylvania Smell Identification Test (UPSIT) while the white matter integrity of the anterior olfactory structures (AOS) was examined using magnetic resonance imaging (MRI) diffusion tensor imaging (DTI) analysis. Those with PD-MCI demonstrated poorer olfactory functioning and abnormalities based on all DTI parameters in the AOS, relative to PD-NC individuals. OD and microstructural changes in the AOS of individuals with PD may serve as additional biological markers of PD-MCI.

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Human Brain Diffusion Tensor Imaging Visualization With Virtual Reality

ASME 2010 World Conference on Innovative Virtual Reality ◽

10.1115/winvr2010-3761 ◽

2010 ◽

Author(s):

Bin Chen ◽

John Moreland

Keyword(s):

Virtual Reality ◽

Diffusion Tensor Imaging ◽

White Matter ◽

Diffusion Tensor ◽

Biological Tissues ◽

Head Tracking ◽

Fiber Tractography ◽

Brain White Matter ◽

Diffusion Tensors ◽

Visualization Techniques

Magnetic resonance diffusion tensor imaging (DTI) is sensitive to the anisotropic diffusion of water exerted by its macromolecular environment and has been shown useful in characterizing structures of ordered tissues such as the brain white matter, myocardium, and cartilage. The water diffusivity inside of biological tissues is characterized by the diffusion tensor, a rank-2 symmetrical 3×3 matrix, which consists of six independent variables. The diffusion tensor contains much information of diffusion anisotropy. However, it is difficult to perceive the characteristics of diffusion tensors by looking at the tensor elements even with the aid of traditional three dimensional visualization techniques. There is a need to fully explore the important characteristics of diffusion tensors in a straightforward and quantitative way. In this study, a virtual reality (VR) based MR DTI visualization with high resolution anatomical image segmentation and registration, ROI definition and neuronal white matter fiber tractography visualization and fMRI activation map integration is proposed. The VR application will utilize brain image visualization techniques including surface, volume, streamline and streamtube rendering, and use head tracking and wand for navigation and interaction, the application will allow the user to switch between different modalities and visualization techniques, as well making point and choose queries. The main purpose of the application is for basic research and clinical applications with quantitative and accurate measurements to depict the diffusivity or the degree of anisotropy derived from the diffusion tensor.

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