A case study of diminished visual-constructional ability, left-handed praxic function, attention and memory following a lesion within the splenium of the corpus callosum and retrosplenial white matter

Objective: Application of diffusion tensor imaging (DTI) to explore the changes of FA value in patients with Parkinson's disease (PD) with mild cognitive impairment. Methods: 27 patients with PD were divided into PD with mild cognitive impairment (PD-MCI) group (n = 7) and PD group (n = 20). The original images were processed using voxel-based analysis (VBA) and tract-based spatial statistics (TBSS). Results: The average age of pd-mci group was longer than that of PD group, and the course of disease was longer than that of PD group. Compared with PD group, the voxel based analysis-fractional anisotropy (VBA-FA) values of PD-MCI group decreased in the following areas: bilateral frontal lobe, bilateral temporal lobe, bilateral parietal lobe, bilateral subthalamic nucleus, corpus callosum, and gyrus cingula. Tract-based spatial statistics-fractional anisotropy (TBSS-FA) values in PD-MCI group decreased in bilateral corticospinal tract, anterior cingulum, posterior cingulum, fornix tract, bilateral superior thalamic radiation, corpus callosum(genu, body and splenium), bilateral uncinate fasciculus, bilateral inferior longitudinal fasciculus, bilateral superior longitudinal fasciculus, bilateral superior fronto-occipital fasciculus, bilateral inferior fronto-occipital fasciculus, and bilateral parietal-occipital tracts. The mean age of onset in the PD-MCI group was greater than that in the PD group, and the disease course was longer than that in the PD group. Conclusion: DTI-based VBA and TBSS post-processing methods can detect abnormalities in multiple brain areas and white matter fiber tracts in PD-MCI patients. Impairment of multiple cerebral cortex and white matter fiber pathways may be an important causes of cognitive dysfunction in PD-MCI.

Download Full-text

Topographic patterns of white matter hyperintensities are associated with multimodal neuroimaging biomarkers of Alzheimer’s disease

Alzheimer s Research & Therapy ◽

10.1186/s13195-020-00759-3 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Malo Gaubert ◽

Catharina Lange ◽

Antoine Garnier-Crussard ◽

Theresa Köbe ◽

Salma Bougacha ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

White Matter ◽

Glucose Metabolism ◽

Corpus Callosum ◽

Gray Matter ◽

Fdg Pet ◽

White Matter Hyperintensities ◽

Gray Matter Volume ◽

Matter Volume

Abstract Background White matter hyperintensities (WMH) are frequently found in Alzheimer’s disease (AD). Commonly considered as a marker of cerebrovascular disease, regional WMH may be related to pathological hallmarks of AD, including beta-amyloid (Aβ) plaques and neurodegeneration. The aim of this study was to examine the regional distribution of WMH associated with Aβ burden, glucose hypometabolism, and gray matter volume reduction. Methods In a total of 155 participants (IMAP+ cohort) across the cognitive continuum from normal cognition to AD dementia, FLAIR MRI, AV45-PET, FDG-PET, and T1 MRI were acquired. WMH were automatically segmented from FLAIR images. Mean levels of neocortical Aβ deposition (AV45-PET), temporo-parietal glucose metabolism (FDG-PET), and medial-temporal gray matter volume (GMV) were extracted from processed images using established AD meta-signature templates. Associations between AD brain biomarkers and WMH, as assessed in region-of-interest and voxel-wise, were examined, adjusting for age, sex, education, and systolic blood pressure. Results There were no significant associations between global Aβ burden and region-specific WMH. Voxel-wise WMH in the splenium of the corpus callosum correlated with greater Aβ deposition at a more liberal threshold. Region- and voxel-based WMH in the posterior corpus callosum, along with parietal, occipital, and frontal areas, were associated with lower temporo-parietal glucose metabolism. Similarly, lower medial-temporal GMV correlated with WMH in the posterior corpus callosum in addition to parietal, occipital, and fontal areas. Conclusions This study demonstrates that local white matter damage is correlated with multimodal brain biomarkers of AD. Our results highlight modality-specific topographic patterns of WMH, which converged in the posterior white matter. Overall, these cross-sectional findings corroborate associations of regional WMH with AD-typical Aß deposition and neurodegeneration.

Download Full-text

The Role of White Matter Disconnection in the Symptoms Relating to the Anarchic Hand Syndrome: A Single Case Study

Brain Sciences ◽

10.3390/brainsci11050632 ◽

2021 ◽

Vol 11 (5) ◽

pp. 632

Author(s):

Valentina Pacella ◽

Giuseppe Kenneth Ricciardi ◽

Silvia Bonadiman ◽

Elisabetta Verzini ◽

Federica Faraoni ◽

...

Keyword(s):

White Matter ◽

Single Case ◽

Brain Lesion ◽

Structural Connectivity ◽

Disconnection Syndrome ◽

Neuroimaging Data ◽

Neuropsychological Investigation ◽

Anterior Posterior

The anarchic hand syndrome refers to an inability to control the movements of one’s own hand, which acts as if it has a will of its own. The symptoms may differ depending on whether the brain lesion is anterior, posterior, callosal or subcortical, but the relative classifications are not conclusive. This study investigates the role of white matter disconnections in a patient whose symptoms are inconsistent with the mapping of the lesion site. A repeated neuropsychological investigation was associated with a review of the literature on the topic to identify the frequency of various different symptoms relating to this syndrome. Furthermore, an analysis of the neuroimaging regarding structural connectivity allowed us to investigate the grey matter lesions and white matter disconnections. The results indicated that some of the patient’s symptoms were associated with structures that, although not directly damaged, were dysfunctional due to a disconnection in their networks. This suggests that the anarchic hand may be considered as a disconnection syndrome involving the integration of multiple antero-posterior, insular and interhemispheric networks. In order to comprehend this rare syndrome better, the clinical and neuroimaging data need to be integrated with the clinical reports available in the literature on this topic.

Download Full-text

Structural brain signature of cognitive decline in Parkinson’s disease: DTI-based evidence from the LANDSCAPE study

Therapeutic Advances in Neurological Disorders ◽

10.1177/1756286419843447 ◽

2019 ◽

Vol 12 ◽

pp. 175628641984344 ◽

Cited By ~ 3

Author(s):

Martin Gorges ◽

Hans-Peter Müller ◽

Inga Liepelt-Scarfone ◽

Alexander Storch ◽

Richard Dodel ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

White Matter ◽

Corpus Callosum ◽

Cognitive Decline ◽

Diffusion Tensor ◽

Structural Connectivity ◽

Structural Data ◽

The Body ◽

Normal Cognitive Function

Background: The nonmotor symptom spectrum of Parkinson’s disease (PD) includes progressive cognitive decline mainly in late stages of the disease. The aim of this study was to map the patterns of altered structural connectivity of patients with PD with different cognitive profiles ranging from cognitively unimpaired to PD-associated dementia. Methods: Diffusion tensor imaging and neuropsychological data from the observational multicentre LANDSCAPE study were analyzed. A total of 134 patients with PD with normal cognitive function (56 PD-N), mild cognitive impairment (67 PD-MCI), and dementia (11 PD-D) as well as 72 healthy controls were subjected to whole-brain-based fractional anisotropy mapping and covariance analysis with cognitive performance measures. Results: Structural data indicated subtle changes in the corpus callosum and thalamic radiation in PD-N, whereas severe white matter impairment was observed in both PD-MCI and PD-D patients including anterior and inferior fronto-occipital, uncinate, insular cortices, superior longitudinal fasciculi, corona radiata, and the body of the corpus callosum. These regional alterations were demonstrated for PD-MCI and were more pronounced in PD-D. The pattern of involved regions was significantly correlated with the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) total score. Conclusions: The findings in PD-N suggest impaired cross-hemispherical white matter connectivity that can apparently be compensated for. More pronounced involvement of the corpus callosum as demonstrated for PD-MCI together with affection of fronto-parieto-temporal structural connectivity seems to lead to gradual disruption of cognition-related cortico-cortical networks and to be associated with the onset of overt cognitive deficits. The increase of regional white matter damage appears to be associated with the development of PD-associated dementia.

Download Full-text

THE METABOLISM OF NORMAL BRAIN AND HUMAN GLIOMAS IN RELATION TO CELL TYPE AND DENSITY

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o55-052 ◽

1955 ◽

Vol 33 (3) ◽

pp. 395-403 ◽

Cited By ~ 37

Author(s):

Irving H. Heller ◽

K. A. C. Elliott

Keyword(s):

Cerebral Cortex ◽

White Matter ◽

Brain Tumors ◽

Corpus Callosum ◽

Oxygen Uptake ◽

Glial Cells ◽

Cerebellar Cortex ◽

Unit Weight ◽

Uptake Rates ◽

The Brain

Per unit weight, cerebral and cerebellar cortex respire much more actively than corpus callosum. The rate per cell nucleus is highest in cerebral cortex, lower in corpus callosum, and still lower in cerebellar cortex. The oxygen uptake rates of the brain tumors studied, with the exception of an oligodendroglioma, were about the same as that of white matter on the weight basis but lower than that of cerebral cortex or white matter on the cell basis. In agreement with previous work, an oligodendroglioma respired much more actively than the other tumors. The rates of glycolysis of the brain tumors per unit weight were low but, relative to their respiration rate, glycolysis was higher than in normal gray or white matter. Consideration of the figures obtained leads to the following tentative conclusions: Glial cells of corpus callosum respire more actively than the neurons of the cerebellar cortex. Neurons of the cerebral cortex respire on the average much more actively than neurons of the cerebellar cortex or glial cells. Considerably more than 70% of the oxygen uptake by cerebral cortex is due to neurons. The oxygen uptake rates of normal oligodendroglia and astrocytes are probably about the same as the rates found per nucleus in an oligodendroglioma and in astrocytomas; oligodendroglia respire much more actively than astrocytes.

Download Full-text