scholarly journals In Vivo Evaluation of White Matter Integrity and Anterograde Transport in Visual System After Excitotoxic Retinal Injury With Multimodal MRI and OCT

2015 ◽  
Vol 56 (6) ◽  
pp. 3788 ◽  
Author(s):  
Leon C. Ho ◽  
Bo Wang ◽  
Ian P. Conner ◽  
Yolandi van der Merwe ◽  
Richard A. Bilonick ◽  
...  
Keyword(s):  
White Matter ◽  
Visual System ◽  
White Matter Integrity ◽  
In Vivo Evaluation ◽  
Anterograde Transport ◽  
Retinal Injury ◽  
Multimodal Mri

scholarly journals Whole-brain 3D MR fingerprinting brain imaging: clinical validation and feasibility to patients with meningioma

2021 ◽  
Author(s):  
Thomaz R. Mostardeiro ◽  
Ananya Panda ◽  
Robert J. Witte ◽  
Norbert G. Campeau ◽  
Kiaran P. McGee ◽  
...  
Keyword(s):  
White Matter ◽  
Statistical Significance ◽  
Relaxation Times ◽  
Brain Structures ◽  
Centrum Semiovale ◽  
In Vivo Evaluation ◽  
Whole Brain ◽  
Mean Values ◽  
Caudate Head

Abstract Purpose MR fingerprinting (MRF) is a MR technique that allows assessment of tissue relaxation times. The purpose of this study is to evaluate the clinical application of this technique in patients with meningioma. Materials and methods A whole-brain 3D isotropic 1mm3 acquisition under a 3.0T field strength was used to obtain MRF T1 and T2-based relaxometry values in 4:38 s. The accuracy of values was quantified by scanning a quantitative MR relaxometry phantom. In vivo evaluation was performed by applying the sequence to 20 subjects with 25 meningiomas. Regions of interest included the meningioma, caudate head, centrum semiovale, contralateral white matter and thalamus. For both phantom and subjects, mean values of both T1 and T2 estimates were obtained. Statistical significance of differences in mean values between the meningioma and other brain structures was tested using a Friedman’s ANOVA test. Results MR fingerprinting phantom data demonstrated a linear relationship between measured and reference relaxometry estimates for both T1 (r2 = 0.99) and T2 (r2 = 0.97). MRF T1 relaxation times were longer in meningioma (mean ± SD 1429 ± 202 ms) compared to thalamus (mean ± SD 1054 ± 58 ms; p = 0.004), centrum semiovale (mean ± SD 825 ± 42 ms; p < 0.001) and contralateral white matter (mean ± SD 799 ± 40 ms; p < 0.001). MRF T2 relaxation times were longer for meningioma (mean ± SD 69 ± 27 ms) as compared to thalamus (mean ± SD 27 ± 3 ms; p < 0.001), caudate head (mean ± SD 39 ± 5 ms; p < 0.001) and contralateral white matter (mean ± SD 35 ± 4 ms; p < 0.001) Conclusions Phantom measurements indicate that the proposed 3D-MRF sequence relaxometry estimations are valid and reproducible. For in vivo, entire brain coverage was obtained in clinically feasible time and allows quantitative assessment of meningioma in clinical practice.

scholarly journals Insights into smouldering MS brain pathology with multimodal diffusion tensor and PET imaging

2020 ◽  
Author(s):  
Svetlana Bezukladova ◽  
Jouni Tuisku ◽  
Markus Matilainen ◽  
Anna Vuorimaa ◽  
Marjo Nylund ◽  
...  
Keyword(s):  
White Matter ◽  
Pet Imaging ◽  
Microglial Activation ◽  
Diffusion Tensor ◽  
Volume Ratio ◽  
Translocator Protein ◽  
Control Group ◽  
In Vivo Evaluation ◽  
Conventional Mri

Objective: To evaluate in vivo the co-occurrence of microglial activation and microstructural white matter damage in multiple sclerosis (MS) brain, and to examine their association with clinical disability. Methods: 18-kDa translocator protein (TSPO) brain PET imaging was performed for evaluation of microglial activation by using the radioligand [11C](R)-PK11195. TSPO-binding was evaluated as the distribution volume ratio (DVR) from dynamic PET images. Diffusion tensor imaging (DTI) and conventional MRI were performed at the same time. Mean fractional anisotropy (FA) and mean (MD), axial (AD) and radial (RD) diffusivities were calculated within the whole normal appearing white matter (NAWM) and segmented NAWM regions appearing normal in conventional MRI. 55 MS patients and 15 healthy controls were examined. Results: Microstructural damage was observed in the NAWM of MS brain. DTI parameters of MS patients were significantly altered in the NAWM, when compared to an age- and sex-matched healthy control group: mean FA was decreased, and MD, AD and RD were increased. These structural abnormalities correlated with increased TSPO binding in the whole NAWM and in the temporal NAWM (p<0.05 for all correlations; p<0.01 for RD in the temporal NAWM). Both compromised WM integrity and increased microglial activation in the NAWM correlated significantly with higher clinical disability measured with expanded disability status scale (EDSS). Conclusions: Widespread structural disruption in the NAWM is linked to neuroinflammation, and both phenomena associate with clinical disability. Multimodal PET and DTI imaging allows in vivo evaluation of widespread MS pathology not visible using conventional MRI.

In vivo evaluation of white matter pathology in patients of progressive supranuclear palsy using TBSS

2011 ◽  
Vol 54 (7) ◽  
pp. 771-780 ◽  
Author(s):  
Jitender Saini ◽  
Bhavani Shankara Bagepally ◽  
Mangalore Sandhya ◽  
Shaik Afsar Pasha ◽  
Ravi Yadav ◽  
...  
Keyword(s):  
White Matter ◽  
Progressive Supranuclear Palsy ◽  
In Vivo Evaluation ◽  
White Matter Pathology

In vivo imaging of oxidative stress and fronto-limbic white matter integrity in young adults with mood disorders

2017 ◽  
Vol 268 (2) ◽  
pp. 145-156 ◽  
Author(s):  
Daniel F. Hermens ◽  
Sean N. Hatton ◽  
Rico S. C. Lee ◽  
Sharon L. Naismith ◽  
Shantel L. Duffy ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Young Adults ◽  
White Matter ◽  
Mood Disorders ◽  
In Vivo Imaging ◽  
White Matter Integrity

scholarly journals In Vivo Evaluation of Retinal Injury After Transient Ischemia in Hypertensive Rats

Hypertension ◽  
2004 ◽  
Vol 43 (5) ◽  
pp. 1098-1102 ◽  
Author(s):  
Fumitaka Hirose ◽  
Junichi Kiryu ◽  
Kazuaki Miyamoto ◽  
Kazuaki Nishijima ◽  
Shinsuke Miyahara ◽  
...  
Keyword(s):  
Hypertensive Rats ◽  
Transient Ischemia ◽  
In Vivo Evaluation ◽  
Retinal Injury

scholarly journals Dorsal White Matter Integrity and Name Retrieval in Midlife

2019 ◽  
Vol 12 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Vanja Kljajevic ◽  
Asier Erramuzpe
Keyword(s):  
White Matter ◽  
Diffusion Tensor ◽  
Mean Diffusivity ◽  
White Matter Integrity ◽  
Middle Aged ◽  
Significant Group ◽  
Proper Name ◽  
The Right ◽  
Name Retrieval

Background: Recent findings on retrieval of proper names in cognitively healthy middle- aged persons indicate that Tip-Of-The-Tongue (TOT) states occurring during proper name retrieval implicate inferior frontal (BA 44) and parietal (BA 40) cortical areas. Such findings give rise to the possibility that anatomical connectivity via dorsal white matter may be associated with difficulties in name retrieval in midlife. Objectives & Method: Using Diffusion Tensor Imaging, we examined in vivo microstructural properties of white matter in 72 cognitively healthy Middle-Aged (MA) and 59 Young Adults (YA), comparing their naming abilities as well as testing, for possible associations between dorsal white matter integrity and naming abilities in the MA group. Results: The MA group was better in retrieving correct names (U = 1525.5, p = .006), but they also retrieved more incorrect names than YA believing they had retrieved the correct ones (U = 1265.5, p < .001). Furthermore, despite being more familiar with the tested names than YA (U = 930, p < .001), MA experienced significantly more TOTs relative to YA (U = 1498.5, p = .004). Tract-based spatial statistics showed significant group differences in values of fractional anisotropy (FA), mean diffusivity, axial diffusivity, radial diffusivity, and mode of anisotropy in a range of white matter tracts. In the MA group, FA values in the right Superior Longitudinal Fasciculus (SLF) were positively correlated with “don’t know” scores (rs = .287, p = .014). Conclusion: The association of SLF integrity and name retrieval ability in midlife indicates a need to revisit the models of name retrieval that posit no role for dorsal white matter in proper name retrieval.

scholarly journals In Vivo Evaluation of White Matter Abnormalities in Children with Duchenne Muscular Dystrophy Using DTI

2020 ◽  
Vol 41 (7) ◽  
pp. 1271-1278
Author(s):  
V. Preethish-Kumar ◽  
A. Shah ◽  
M. Kumar ◽  
M. Ingalhalikar ◽  
K. Polavarapu ◽  
...  
Keyword(s):  
Duchenne Muscular Dystrophy ◽  
White Matter ◽  
Muscular Dystrophy ◽  
In Vivo Evaluation ◽  
White Matter Abnormalities

scholarly journals In vivo evaluation of gray and white matter volume loss in the parkinsonian variant of multiple system atrophy using SPM8 plus DARTEL for VBM

2013 ◽  
Vol 2 ◽  
pp. 491-496 ◽  
Author(s):  
Yoko Shigemoto ◽  
Hiroshi Matsuda ◽  
Kouhei Kamiya ◽  
Norihide Maikusa ◽  
Yasuhiro Nakata ◽  
...  
Keyword(s):  
White Matter ◽  
Multiple System Atrophy ◽  
Volume Loss ◽  
White Matter Volume ◽  
In Vivo Evaluation ◽  
Matter Volume

scholarly journals Alterations in Cortical Thickness and White Matter Integrity in Mild-to-Moderate Communicating Hydrocephalic School-Aged Children Measured by Whole-Brain Cortical Thickness Mapping and DTI

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Siyu Zhang ◽  
Xinjian Ye ◽  
Guanghui Bai ◽  
Yuchuan Fu ◽  
Chuanwan Mao ◽  
...  
Keyword(s):  
White Matter ◽  
Fractional Anisotropy ◽  
Cortical Thickness ◽  
Diffusion Tensor ◽  
Structural Mri ◽  
Middle Frontal Gyrus ◽  
White Matter Integrity ◽  
Communicating Hydrocephalus ◽  
Middle Temporal

Follow-up observation is required for mild-to-moderate hydrocephalic patients because of the potential damage to brain. However, effects of mild-to-moderate hydrocephalus on gray and white matter remain unclear in vivo. Using structural MRI and diffusion tensor imaging (DTI), current study compared the cortical thickness and white matter integrity between children with mild-to-moderate communicating hydrocephalus and healthy controls. The relationships between cortical changes and intelligence quota were also examined in patients. We found that cortical thickness in the left middle temporal and left rostral middle frontal gyrus was significantly lower in the hydrocephalus group compared with that of controls. Fractional anisotropy in the right corpus callosum body was significantly lower in the hydrocephalus group compared with that of controls. In addition, there was no association of cortical thinning or white matter fractional anisotropy with intelligence quota in either group. Thus, our findings provide clues to that mild-to-moderate hydrocephalus could lead to structural brain deficits especially in the middle temporal and middle frontal gyrus prior to the behavior changes.

Sign in / Sign up

Export Citation Format

Share Document