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Peter C.m. Van Zijl - One of the best experts on this subject based on the ideXlab platform.

Markus D. Schirmer - One of the best experts on this subject based on the ideXlab platform.

  • Peak Width of Skeletonized Mean Diffusivity as Neuroimaging Biomarker in Cerebral Amyloid Angiopathy.
    AJNR. American journal of neuroradiology, 2021
    Co-Authors: N. Raposo, Andreas Charidimou, Gregoire Boulouis, M.c. Zanon Zotin, Dorothee Schoemaker, Li Xiong, Panagiotis Fotiadis, M. Pasi, K. Schwab, Markus D. Schirmer
    Abstract:

    BACKGROUND AND PURPOSE Whole-brain network connectivity has been shown to be a useful biomarker of cerebral amyloid angiopathy and related cognitive impairment. We evaluated an automated DTI-based method, peak width of skeletonized Mean Diffusivity, in cerebral amyloid angiopathy, together with its association with conventional MRI markers and cognitive functions. MATERIALS AND METHODS We included 24 subjects (Mean age, 74.7 [SD, 6.0] years) with probable cerebral amyloid angiopathy and mild cognitive impairment and 62 patients with MCI not attributable to cerebral amyloid angiopathy (non-cerebral amyloid angiopathy-mild cognitive impairment). We compared peak width of skeletonized Mean Diffusivity between subjects with cerebral amyloid angiopathy-mild cognitive impairment and non-cerebral amyloid angiopathy-mild cognitive impairment and explored its associations with cognitive functions and conventional markers of cerebral small-vessel disease, using linear regression models. RESULTS Subjects with Cerebral amyloid angiopathy-mild cognitive impairment showed increased peak width of skeletonized Mean Diffusivity in comparison to those with non-cerebral amyloid angiopathy-mild cognitive impairment (P < .001). Peak width of skeletonized Mean Diffusivity values were correlated with the volume of white matter hyperintensities in both groups. Higher peak width of skeletonized Mean Diffusivity was associated with worse performance in processing speed among patients with cerebral amyloid angiopathy, after adjusting for other MRI markers of cerebral small vessel disease. The peak width of skeletonized Mean Diffusivity did not correlate with cognitive functions among those with non-cerebral amyloid angiopathy-mild cognitive impairment. CONCLUSIONS Peak width of skeletonized Mean Diffusivity is altered in cerebral amyloid angiopathy and is associated with performance in processing speed. This DTI-based method may reflect the degree of white matter structural disruption in cerebral amyloid angiopathy and could be a useful biomarker for cognition in this population.

  • Peak Width of Skeletonized Mean Diffusivity as Neuroimaging Biomarker in Cerebral Amyloid Angiopathy
    AJNR. American journal of neuroradiology, 2021
    Co-Authors: N. Raposo, Andreas Charidimou, Gregoire Boulouis, M.c. Zanon Zotin, Dorothee Schoemaker, Li Xiong, Panagiotis Fotiadis, M. Pasi, K. Schwab, Markus D. Schirmer
    Abstract:

    Background and purpose Whole-brain network connectivity has been shown to be a useful biomarker of cerebral amyloid angiopathy and related cognitive impairment. We evaluated an automated DTI-based method, peak width of skeletonized Mean Diffusivity, in cerebral amyloid angiopathy, together with its association with conventional MRI markers and cognitive functions. Materials and methods We included 24 subjects (Mean age, 74.7 [SD, 6.0] years) with probable cerebral amyloid angiopathy and mild cognitive impairment and 62 patients with MCI not attributable to cerebral amyloid angiopathy (non-cerebral amyloid angiopathy-mild cognitive impairment). We compared peak width of skeletonized Mean Diffusivity between subjects with cerebral amyloid angiopathy-mild cognitive impairment and non-cerebral amyloid angiopathy-mild cognitive impairment and explored its associations with cognitive functions and conventional markers of cerebral small-vessel disease, using linear regression models. Results Subjects with Cerebral amyloid angiopathy-mild cognitive impairment showed increased peak width of skeletonized Mean Diffusivity in comparison to those with non-cerebral amyloid angiopathy-mild cognitive impairment (P Conclusions Peak width of skeletonized Mean Diffusivity is altered in cerebral amyloid angiopathy and is associated with performance in processing speed. This DTI-based method may reflect the degree of white matter structural disruption in cerebral amyloid angiopathy and could be a useful biomarker for cognition in this population.

Massimo Filippi - One of the best experts on this subject based on the ideXlab platform.

  • Mean Diffusivity and fractional anisotropy histogram analysis of the cervical cord in ms patients
    NeuroImage, 2005
    Co-Authors: Paola Valsasina, Giancarlo Comi, Maria A Rocca, Federica Agosta, B Benedetti, Mark A Horsfield, Antonio Gallo, Marco Rovaris, Massimo Filippi
    Abstract:

    The spinal cord is frequently involved in multiple sclerosis (MS), and cord damage may be an important contributor to disability. Diffusion tensor magnetic resonance imaging (DT-MRI) provides quantitative information about the structural and orientational features of the central nervous system. In order to assess whether diffusion tensor-derived measures of cord tissue damage are related to clinical disability, Mean Diffusivity (MD) and fractional anisotropy (FA) histograms from the cervical cord were acquired from a large cohort of MS patients. Diffusion-weighted sensitivity-encoded (SENSE) echo planar images of the cervical cord, and brain dual-echo and diffusion-weighted scans were acquired from 44 patients with MS and 17 healthy controls. Cord and brain MD and FA histograms were produced. An analysis of variance model, adjusting for cord volume and patient age, was used to compare cord DT-MRI parameters from controls and patients. A multivariate linear regression model was used to identify DT-MRI variables independently associated with disability. Average cervical cord FA was significantly lower in MS patients compared to controls. Cord cross-sectional area, average FA and average MD were all significantly correlated with the degree of disability (r values ranging from 0.36 to 0.51). The multivariate linear regression model retained average cord FA and average brain MD as variables independently associated with disability, with a correlation coefficient of 0.73 (P < 0.001). DT-MRI reveals a loss of cervical cord tissue structure in MS patients. The strong correlation found between a composite DT-MRI score and disability suggests that a full and accurate assessment of cervical cord damage in MS provides information that usefully contributes to an explanation of the clinical manifestations of the disease.

  • magnetisation transfer ratio and Mean Diffusivity of normal appearing white and grey matter from patients with multiple sclerosis
    Journal of Neurology Neurosurgery and Psychiatry, 2001
    Co-Authors: Mara Cercignani, Marco Bozzali, Giuseppe Iannucci, G Comi, Massimo Filippi
    Abstract:

    OBJECTIVE To assess the feasibility of a new technique based on diffusion anisotropy to segment white and grey matter of the brain. To use this technique to measure the Mean Diffusivity ( D ) and magnetisation transfer ratio (MTR) of normal appearing white matter (NAWM) and grey matter (NAGM) from patients with multiple sclerosis. METHODS Dual echo turbo spin echo, MT, and diffusion weighted scans of the brain were obtained from 30 patients with multiple sclerosis and 18 sex and age matched healthy controls. After image coregistration and removal of T2 visible lesions, white and grey matter were segmented from 10 supratentorial slices using diffusion anisotropy thresholds. Histograms of the average MTR and D were created for normal white and grey matter of controls and NAWM and NAGM of patients with multiple sclerosis. RESULTS All the MTR histogram derived metrics of the NAWM from patients with multiple sclerosis were significantly lower than those of white matter from controls. The peak height of the D histogram of NAWM from patients with multiple sclerosis was also significantly different from that of normal white matter. The average MTR, the peak location of the MTR histogram, and peak height of the D histogram of the NAGM of patients with multiple sclerosis were significantly lower than the corresponding quantities of grey matter from controls. CONCLUSIONS A technique was developed for segmenting white and grey matter with the potential for improving the understanding of the pathophysiology of many neurological conditions. Its application to the study of multiple sclerosis confirms the presence of a diffuse tissue damage in the NAWM of these patients and suggests that subtle changes also occur in the NAGM.

  • Mean Diffusivity and fractional anisotropy histograms of patients with multiple sclerosis.
    AJNR. American journal of neuroradiology, 2001
    Co-Authors: Mara Cercignani, Matilde Inglese, Elisabetta Pagani, Giancarlo Comi, Massimo Filippi
    Abstract:

    BACKGROUND AND PURPOSE: Compared with conventional T2-weighted MR imaging, diffusion tensor MR imaging provides quantitative indices with increased specificity to the most destructive aspects of multiple sclerosis. In this study, we obtained brain Mean Diffusivity ( D ) and fractional anisotropy histograms of patients with multiple sclerosis to compare them with those of healthy volunteers and to investigate the correlation between diffusion tensor MR imaging histogram-derived measures and the level of disability and quantities derived from conventional MR imaging. METHODS: Dual-echo and diffusion tensor MR images were obtained from 78 patients with relapsing-remitting, secondary progressive, or primary progressive multiple sclerosis and from 20 healthy control volunteers. After obtaining Mean Diffusivity ( D ) and fractional anisotropy images and image coregistration, D and fractional anisotropy histograms were created. From each histogram, the following measures were derived: the average D and fractional anisotropy, the histogram peak heights, and the histogram peak locations. RESULTS: All the D and fractional anisotropy histogram-derived measures were different between patients and controls at a significance level of P D (r = 0.4, P = .01) and peak height (r = −0.4, P = .01). In patients with secondary progressive multiple sclerosis, disability was correlated with fractional anisotropy histogram peak position (r = −0.6, P = .01). Significant correlations were also found between T2 lesion load and various diffusion tensor MR quantities. CONCLUSION: This study shows that brain D and fractional anisotropy histograms are different for patients with multiple sclerosis compared with control volunteers. This study also shows that quantities derived from diffusion tensor MR imaging are correlated with disability in patients with relapsing-remitting multiple sclerosis and secondary progressive multiple sclerosis, suggesting that they might serve as additional measures of outcome when monitoring multiple sclerosis evolution in these patients.

M.c. Zanon Zotin - One of the best experts on this subject based on the ideXlab platform.

  • Peak Width of Skeletonized Mean Diffusivity as Neuroimaging Biomarker in Cerebral Amyloid Angiopathy.
    AJNR. American journal of neuroradiology, 2021
    Co-Authors: N. Raposo, Andreas Charidimou, Gregoire Boulouis, M.c. Zanon Zotin, Dorothee Schoemaker, Li Xiong, Panagiotis Fotiadis, M. Pasi, K. Schwab, Markus D. Schirmer
    Abstract:

    BACKGROUND AND PURPOSE Whole-brain network connectivity has been shown to be a useful biomarker of cerebral amyloid angiopathy and related cognitive impairment. We evaluated an automated DTI-based method, peak width of skeletonized Mean Diffusivity, in cerebral amyloid angiopathy, together with its association with conventional MRI markers and cognitive functions. MATERIALS AND METHODS We included 24 subjects (Mean age, 74.7 [SD, 6.0] years) with probable cerebral amyloid angiopathy and mild cognitive impairment and 62 patients with MCI not attributable to cerebral amyloid angiopathy (non-cerebral amyloid angiopathy-mild cognitive impairment). We compared peak width of skeletonized Mean Diffusivity between subjects with cerebral amyloid angiopathy-mild cognitive impairment and non-cerebral amyloid angiopathy-mild cognitive impairment and explored its associations with cognitive functions and conventional markers of cerebral small-vessel disease, using linear regression models. RESULTS Subjects with Cerebral amyloid angiopathy-mild cognitive impairment showed increased peak width of skeletonized Mean Diffusivity in comparison to those with non-cerebral amyloid angiopathy-mild cognitive impairment (P < .001). Peak width of skeletonized Mean Diffusivity values were correlated with the volume of white matter hyperintensities in both groups. Higher peak width of skeletonized Mean Diffusivity was associated with worse performance in processing speed among patients with cerebral amyloid angiopathy, after adjusting for other MRI markers of cerebral small vessel disease. The peak width of skeletonized Mean Diffusivity did not correlate with cognitive functions among those with non-cerebral amyloid angiopathy-mild cognitive impairment. CONCLUSIONS Peak width of skeletonized Mean Diffusivity is altered in cerebral amyloid angiopathy and is associated with performance in processing speed. This DTI-based method may reflect the degree of white matter structural disruption in cerebral amyloid angiopathy and could be a useful biomarker for cognition in this population.

  • Peak Width of Skeletonized Mean Diffusivity as Neuroimaging Biomarker in Cerebral Amyloid Angiopathy
    AJNR. American journal of neuroradiology, 2021
    Co-Authors: N. Raposo, Andreas Charidimou, Gregoire Boulouis, M.c. Zanon Zotin, Dorothee Schoemaker, Li Xiong, Panagiotis Fotiadis, M. Pasi, K. Schwab, Markus D. Schirmer
    Abstract:

    Background and purpose Whole-brain network connectivity has been shown to be a useful biomarker of cerebral amyloid angiopathy and related cognitive impairment. We evaluated an automated DTI-based method, peak width of skeletonized Mean Diffusivity, in cerebral amyloid angiopathy, together with its association with conventional MRI markers and cognitive functions. Materials and methods We included 24 subjects (Mean age, 74.7 [SD, 6.0] years) with probable cerebral amyloid angiopathy and mild cognitive impairment and 62 patients with MCI not attributable to cerebral amyloid angiopathy (non-cerebral amyloid angiopathy-mild cognitive impairment). We compared peak width of skeletonized Mean Diffusivity between subjects with cerebral amyloid angiopathy-mild cognitive impairment and non-cerebral amyloid angiopathy-mild cognitive impairment and explored its associations with cognitive functions and conventional markers of cerebral small-vessel disease, using linear regression models. Results Subjects with Cerebral amyloid angiopathy-mild cognitive impairment showed increased peak width of skeletonized Mean Diffusivity in comparison to those with non-cerebral amyloid angiopathy-mild cognitive impairment (P Conclusions Peak width of skeletonized Mean Diffusivity is altered in cerebral amyloid angiopathy and is associated with performance in processing speed. This DTI-based method may reflect the degree of white matter structural disruption in cerebral amyloid angiopathy and could be a useful biomarker for cognition in this population.

  • Abstract P59: Peak Width of Skeletonized Mean Diffusivity Outperforms Other Diffusion Tensor Imaging Metrics as Biomarker for Cognition in Memory-Clinic Subjects With Cerebral Amyloid Angiopathy
    Stroke, 2021
    Co-Authors: M.c. Zanon Zotin, Andreas Charidimou, Dorothee Schoemaker, Valentina Perosa, Martin Bretzner, Lukas Sveikata, Susanne J. Van Veluw, Mark R. Etherton, Edip M Gurol, Steven Greenberg
    Abstract:

    Introduction: Peak width of skeletonized Mean Diffusivity (PSMD) is a novel fully automated diffusion tensor imaging (DTI) marker that has been consistently associated with cognition in cerebral sm...

Seth A. Smith - One of the best experts on this subject based on the ideXlab platform.