The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform

Martin Reivich - One of the best experts on this subject based on the ideXlab platform.

  • neuro imaging and positron emission tomography of congenital homonymous Hemianopsia
    American Journal of Ophthalmology, 1991
    Co-Authors: Thomas M Bosley, Motohiro Kiyosawa, Mark L Moster, Robert Harbour, Robert D Zimmerman, Peter J Savino, Robert C Sergott, Abass Alavi, Martin Reivich
    Abstract:

    Congenital homonymous Hemianopsia is an uncommon asymptomatic visual field defect discovered typically in young adult life that is caused by a diverse group of insults to the retrochiasmal afferent visual system occurring prenatally, at birth, or during early childhood. We treated eight patients with congenital homonymous Hemianopsia; seven with damage involving the optic radiations and one with an abnormality of the optic tract. We performed positron emission tomography using 18 F-fluoro-2-deoxyglucose on two patients with dense homonymous Hemianopsias, lesions of the contralateral optic radiations, and largely intact occipital cortex. These studies showed minimal abnormalities in resting visual cortex glucose metabolism of the affected visual cortex.

Michael V Boland - One of the best experts on this subject based on the ideXlab platform.

Thomas M Bosley - One of the best experts on this subject based on the ideXlab platform.

  • neuro imaging and positron emission tomography of congenital homonymous Hemianopsia
    American Journal of Ophthalmology, 1991
    Co-Authors: Thomas M Bosley, Motohiro Kiyosawa, Mark L Moster, Robert Harbour, Robert D Zimmerman, Peter J Savino, Robert C Sergott, Abass Alavi, Martin Reivich
    Abstract:

    Congenital homonymous Hemianopsia is an uncommon asymptomatic visual field defect discovered typically in young adult life that is caused by a diverse group of insults to the retrochiasmal afferent visual system occurring prenatally, at birth, or during early childhood. We treated eight patients with congenital homonymous Hemianopsia; seven with damage involving the optic radiations and one with an abnormality of the optic tract. We performed positron emission tomography using 18 F-fluoro-2-deoxyglucose on two patients with dense homonymous Hemianopsias, lesions of the contralateral optic radiations, and largely intact occipital cortex. These studies showed minimal abnormalities in resting visual cortex glucose metabolism of the affected visual cortex.

Neil R Miller - One of the best experts on this subject based on the ideXlab platform.

Shanbao Tong - One of the best experts on this subject based on the ideXlab platform.

  • Enhanced Effective Connectivity in Mild Occipital Stroke Patients With Hemianopia
    IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2014
    Co-Authors: Xinyang Feng, Shanbao Tong
    Abstract:

    Plasticity-based spontaneous recovery and rehabilitation intervention of stroke-induced hemianopia have drawn great attention in recent years. However, the underlying neural mechanism remains unknown. This study aims to investigate brain network disruption and reorganization in hemianopia patients due to mild occipital stroke. Resting-state networks were constructed from 12 hemianopia patients with right occipital infarct by partial directed coherence analysis of multi-channel electroencephalograms. Compared with control subjects, the patients presented enhanced connectivity owing to newly formed connections. Compensational connections mostly originated from the peri-infarct area and targeted contralesional frontal, central, and parietal cortices. These new ipsilesional-to-contralesional inter-hemispheric connections coordinately presented significant correlation with the extent of vision loss. The enhancement of connectivity might be the neural substrate for brain plasticity in stroke-induced hemianopia and may shed light on plasticity-based recovery or rehabilitation.

  • Cortical networks of hemianopia stroke patients: A graph theoretical analysis of EEG signals at resting state
    2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2012
    Co-Authors: Lei Wang, Shanbao Tong
    Abstract:

    Visual cortical stroke patients may have hemianopia symptom, which affects a number of visual functions. Most studies on hemianopia stroke have mainly focused on cortical activation during visual stimulation, leaving the pattern of functional connectivity between different brain regions uncovered yet. In the present study, we investigate the resting neural networks of hemianopia stroke patients by graph theoretical analysis of functional brain networks constructed with phase synchronization indexes of multichannel electroencephalography (EEG) signals. Our results showed that although the global network topological metrics, i.e., weighted clustering coefficient and characteristic path length of patients and healthy controls are comparable, the left primary visual cortex of patients tend to be less active than that of age-matched healthy subjects. However, hemianopia patients showed greater activation in the ipsilesional (left) temporopolar and orbit frontal areas and the contralesional (right) associative visual cortex. These results may offer new insight into neural substrates of the hemianopia stroke, and the further study of neural plasticity and brain reorganization after hemianopia.