The Experts below are selected from a list of 387 Experts worldwide ranked by ideXlab platform
Christian Gaser - One of the best experts on this subject based on the ideXlab platform.
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Volumenänderungen der grauen Hirnsubstanz bei Anosmikern: Erkenntnisse durch voxelbasierte Morphometrie
HNO, 2011Co-Authors: Thomas Bitter, H P Burmeister, H J Mentzel, Hilmar Gudziol, Christian Gaser, Orlando Guntinas-lichiusAbstract:Alterations in the central nervous system in patients with a loss of sense of smell are well documented for the olfactory bulb (OB). Here we present a voxel-based morphometry (VBM) study on cerebral alterations in the gray matter of patients with anosmia above the OB. 3-Tesla MRI datasets were obtained from 17 patients with anosmia as well as from 17 normosmic controls. Data processing and evaluation was performed using the SPM5 software package (Wellcome Department of Imaging Neuroscience Group, London, UK) and the implemented VBM5 tool-box. Patients with anosmia showed a significant volume decrease in the gray matter in the primary olfactory cortex as well as in secondary olfactory areas (insular cortex, orbitofrontal cortex, cingulate cortex and hippocampus). Furthermore, volume decreases in areas like the nucleus accumbens with adjacent Subcallosal Gyrus and the dorsolateral prefrontal cortex were found. Longer disease duration was associated with more profound alterations in the gray matter. VBM is appropriate to document brain alterations in patients with olfactory disorders.
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Volumenänderungen der grauen Hirnsubstanz bei Anosmikern
HNO, 2011Co-Authors: T. Bitter, H J Mentzel, Hilmar Gudziol, Christian Gaser, H.p. Burmeister, Orlando Guntinas-lichiusAbstract:Alterations in the central nervous system in patients with a loss of sense of smell are well documented for the olfactory bulb (OB). Here we present a voxel-based morphometry (VBM) study on cerebral alterations in the gray matter of patients with anosmia above the OB. 3-Tesla MRI datasets were obtained from 17 patients with anosmia as well as from 17 normosmic controls. Data processing and evaluation was performed using the SPM5 software package (Wellcome Department of Imaging Neuroscience Group, London, UK) and the implemented VBM5 toolbox. Patients with anosmia showed a significant volume decrease in the gray matter in the primary olfactory cortex as well as in secondary olfactory areas (insular cortex, orbitofrontal cortex, cingulate cortex and hippocampus). Furthermore, volume decreases in areas like the nucleus accumbens with adjacent Subcallosal Gyrus and the dorsolateral prefrontal cortex were found. Longer disease duration was associated with more profound alterations in the gray matter. VBM is appropriate to document brain alterations in patients with olfactory disorders. Veränderungen des zentralen Nervensystems nach einem Verlust des Riechvermögens wurden bisher vor allem für den Bulbus olfactorius (OB) beschrieben. Wir stellen eine Studie zu voxelbasierter Morphometrie (VBM) vor, die Hirnveränderungen bei Patienten mit Anosmie in dem OB übergeordneten Arealen darstellt. Datensätze von 17 Patienten mit Anosmie sowie von 17 normosmischen Kontrollpersonen wurden auf einem 3-T-Magnetresonanztomographen aufgezeichnet. Die Datenverarbeitung und Auswertung erfolgte mit der SPM5-Software (Wellcome Department of Imaging Neuroscience Group, London, UK) und der hierin implementierten VBM5-Toolbox. Die Patientengruppe zeigte eine signifikante Volumenabnahme der grauen Hirnsubstanz sowohl im primären olfaktorischen Kortex als auch in sekundären olfaktorischen Arealen (Insula, orbitofrontaler Kortex, Cingulum, Hippokampus). Auch wurden größere Volumenabnahmen im Nucleus accumbens mit dem angrenzenden Gyrus subcallosus sowie im dorsolateralen präfrontalen Kortex gefunden. Eine längere Erkrankungsdauer war mit ausgeprägteren Gehirnveränderungen verbunden. VBM ist somit geeignet, Hirnveränderungen bei Patienten mit Riechstörungen darzustellen.
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anosmia leads to a loss of gray matter in cortical brain areas
Chemical Senses, 2010Co-Authors: Thomas Bitter, H P Burmeister, H J Mentzel, Orlando Guntinaslichius, Hilmar Gudziol, Christian GaserAbstract:Chronic olfactory disorders, including the complete loss of the sense of smell (anosmia), are common. Using voxel-based morphometry (VBM) in magnetic resonance imaging (MRI), structural changes in the cerebral gray matter (GM) of a group of patients with anosmia compared with a normosmic, healthy control group were evaluated. Patients with anosmia presented a significant decrease of GM volume mainly in the nucleus accumbens with adjacent Subcallosal Gyrus, in the medial prefrontal cortex (MPC) including the middle and anterior cingulate cortices, and in the dorsolateral prefrontal cortex (dlPFC). These areas are part of the limbic loop of the basal ganglia and except the dlPFC secondary olfactory areas. They also play an important role in many neurological diseases. Furthermore, volume decreases in smaller areas like the piriform cortex, insular cortex, orbitofrontal cortex, hippocampus, parahippocampal Gyrus, supramarginal Gyrus, and cerebellum could be seen. Longer disease duration was associated with a stronger atrophy in the described areas. No local increases in the GM volume could be observed. A comparison with results of an additionally executed functional MRI study on olfaction in healthy subjects was performed to evaluate the significance of the observed atrophy areas in cerebral olfactory processing. To our knowledge, this is the first study on persisting structural changes in cortical GM volume after complete olfactory loss.
Harry T. Chugani - One of the best experts on this subject based on the ideXlab platform.
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Original Article Altered Fronto-Striato-Thalamic Connectivity in Children With Tourette Syndrome AssessedWith Diffusion Tensor MRI and Probabilistic Fiber Tracking
2016Co-Authors: Michael E. Behen, Harry T. ChuganiAbstract:The aim of the study was to determine whether abnormal connectivity of the fronto-striato-thalamic circuit underlies the morphological changes in subcortical structures of patients with Tourette syndrome and to correlate these changes with neurobehavioral measures. A total of 18 children with Tourette syndrome and 12 age-matched healthy controls underwent diffusion tensor magnetic resonance imaging. Tractography of the fronto-striato-thalamic circuit was achieved using probability distribution function of individual voxels. The Tourette syndrome group had significantly lower probability of connection between caudate nucleus and anterior-dorsolateral-frontal cortex on the left (P .038). Obsessive-compulsive behavior was negatively associated with connectivity score of the left caudate and anterior dorsolateral frontal cortex (P .01) and was positively associated with con-nectivity score for the Subcallosal Gyrus (P .009) and for the lentiform nucleus (P .008). The abnormal connectivity among components of the fronto-striato-thalamic circuit bilat-erally (ie, seeds on the caudate and thalamus) in patients with Tourette syndrome provides direct evidence for the involve-ment of these circuits in the pathophysiology
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Altered fronto-striato-thalamic connectivity in children with Tourette syndrome assessed with diffusion tensor MRI and probabilistic fiber tracking.
Journal of Child Neurology, 2009Co-Authors: Malek I. Makki, Rajkumar Munian Govindan, Benjamin J. Wilson, Michael E. Behen, Harry T. ChuganiAbstract:The aim of the study was to determine whether abnormal connectivity of the fronto-striato-thalamic circuit underlies the morphological changes in subcortical structures of patients with Tourette syndrome and to correlate these changes with neurobehavioral measures. A total of 18 children with Tourette syndrome and 12 age-matched healthy controls underwent diffusion tensor magnetic resonance imaging. Tractography of the fronto-striato-thalamic circuit was achieved using probability distribution function of individual voxels. The Tourette syndrome group had significantly lower probability of connection between caudate nucleus and anterior-dorsolateral-frontal cortex on the left (P = .038). Obsessive-compulsive behavior was negatively associated with connectivity score of the left caudate and anterior dorsolateral frontal cortex (P = .01) and was positively associated with connectivity score for the Subcallosal Gyrus (P = .009) and for the lentiform nucleus (P = .008). The abnormal connectivity among components of the fronto-striato-thalamic circuit bilaterally (ie, seeds on the caudate and thalamus) in patients with Tourette syndrome provides direct evidence for the involvement of these circuits in the pathophysiology.
Yasushi Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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Photon Emission Tomography with 3D Stereotactic Surface
2014Co-Authors: Hexamethylpropyleneamine Oxime Single, Kazuo Takahashi, Shuhei Yamaguchi, Shotai Kobayashi, Yasushi YamamotoAbstract:OBJECTIVES: Although many previous reports have described age-related changes in re-gional cerebral blood flow (rCBF), none has used 3D stereotactic surface projection (3D-SSP) analysis, which is able to detect subtle and significant changes in rCBF. METHODS: The subjects were 31 healthy volunteers (16 men and 15 women; 50–79 years of age) without abnormal MR imaging and MR angiographic findings, cognitive impairment, or depression. For each subject, rCBF was evaluated by using technetium Tc 99m-radiolabeled hexamethylpropyleneamine oxime single-photon emission CT. Maps of rCBF were compared among different age groups (50–59, 60–69, and 70–79 years of age) by using 3D-SSP. The mean z score for each Gyrus was calculated for each age group by using a recently developed stereotactic extraction estimation method. RESULTS: Significant age-related reductions in rCBF were seen in the bilateral cingulate gyri, left inferior Gyrus, bilateral medial frontal gyri, left Subcallosal Gyrus, and left superior temporal Gyrus. Extensive and constant reduction in rCBF occurred with increasing age in the bilateral anterior cingulate gyri, and the mean z score for this region was the highest among all the regions examined
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Effects of Aging on Regional Cerebral Blood Flow Assessed By Using Technetium Tc 99m Hexamethylpropyleneamine Oxime Single-Photon Emission Tomography with 3D Stereotactic Surface Projection Analysis
AJNR. American journal of neuroradiology, 2005Co-Authors: Kazuo Takahashi, Shuhei Yamaguchi, Shotai Kobayashi, Yasushi YamamotoAbstract:OBJECTIVES: Although many previous reports have described age-related changes in regional cerebral blood flow (rCBF), none has used 3D stereotactic surface projection (3D-SSP) analysis, which is able to detect subtle and significant changes in rCBF. METHODS: The subjects were 31 healthy volunteers (16 men and 15 women; 50–79 years of age) without abnormal MR imaging and MR angiographic findings, cognitive impairment, or depression. For each subject, rCBF was evaluated by using technetium Tc 99m-radiolabeled hexamethylpropyleneamine oxime single-photon emission CT. Maps of rCBF were compared among different age groups (50–59, 60–69, and 70–79 years of age) by using 3D-SSP. The mean z score for each Gyrus was calculated for each age group by using a recently developed stereotactic extraction estimation method. RESULTS: Significant age-related reductions in rCBF were seen in the bilateral cingulate gyri, left inferior Gyrus, bilateral medial frontal gyri, left Subcallosal Gyrus, and left superior temporal Gyrus. Extensive and constant reduction in rCBF occurred with increasing age in the bilateral anterior cingulate gyri, and the mean z score for this region was the highest among all the regions examined. CONCLUSION: The 3D-SSP analysis revealed that the greatest reduction in rCBF occurred within the bilateral anterior cingulate gyri in normal middle-aged and older subjects.
Hilmar Gudziol - One of the best experts on this subject based on the ideXlab platform.
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Volumenänderungen der grauen Hirnsubstanz bei Anosmikern: Erkenntnisse durch voxelbasierte Morphometrie
HNO, 2011Co-Authors: Thomas Bitter, H P Burmeister, H J Mentzel, Hilmar Gudziol, Christian Gaser, Orlando Guntinas-lichiusAbstract:Alterations in the central nervous system in patients with a loss of sense of smell are well documented for the olfactory bulb (OB). Here we present a voxel-based morphometry (VBM) study on cerebral alterations in the gray matter of patients with anosmia above the OB. 3-Tesla MRI datasets were obtained from 17 patients with anosmia as well as from 17 normosmic controls. Data processing and evaluation was performed using the SPM5 software package (Wellcome Department of Imaging Neuroscience Group, London, UK) and the implemented VBM5 tool-box. Patients with anosmia showed a significant volume decrease in the gray matter in the primary olfactory cortex as well as in secondary olfactory areas (insular cortex, orbitofrontal cortex, cingulate cortex and hippocampus). Furthermore, volume decreases in areas like the nucleus accumbens with adjacent Subcallosal Gyrus and the dorsolateral prefrontal cortex were found. Longer disease duration was associated with more profound alterations in the gray matter. VBM is appropriate to document brain alterations in patients with olfactory disorders.
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Volumenänderungen der grauen Hirnsubstanz bei Anosmikern
HNO, 2011Co-Authors: T. Bitter, H J Mentzel, Hilmar Gudziol, Christian Gaser, H.p. Burmeister, Orlando Guntinas-lichiusAbstract:Alterations in the central nervous system in patients with a loss of sense of smell are well documented for the olfactory bulb (OB). Here we present a voxel-based morphometry (VBM) study on cerebral alterations in the gray matter of patients with anosmia above the OB. 3-Tesla MRI datasets were obtained from 17 patients with anosmia as well as from 17 normosmic controls. Data processing and evaluation was performed using the SPM5 software package (Wellcome Department of Imaging Neuroscience Group, London, UK) and the implemented VBM5 toolbox. Patients with anosmia showed a significant volume decrease in the gray matter in the primary olfactory cortex as well as in secondary olfactory areas (insular cortex, orbitofrontal cortex, cingulate cortex and hippocampus). Furthermore, volume decreases in areas like the nucleus accumbens with adjacent Subcallosal Gyrus and the dorsolateral prefrontal cortex were found. Longer disease duration was associated with more profound alterations in the gray matter. VBM is appropriate to document brain alterations in patients with olfactory disorders. Veränderungen des zentralen Nervensystems nach einem Verlust des Riechvermögens wurden bisher vor allem für den Bulbus olfactorius (OB) beschrieben. Wir stellen eine Studie zu voxelbasierter Morphometrie (VBM) vor, die Hirnveränderungen bei Patienten mit Anosmie in dem OB übergeordneten Arealen darstellt. Datensätze von 17 Patienten mit Anosmie sowie von 17 normosmischen Kontrollpersonen wurden auf einem 3-T-Magnetresonanztomographen aufgezeichnet. Die Datenverarbeitung und Auswertung erfolgte mit der SPM5-Software (Wellcome Department of Imaging Neuroscience Group, London, UK) und der hierin implementierten VBM5-Toolbox. Die Patientengruppe zeigte eine signifikante Volumenabnahme der grauen Hirnsubstanz sowohl im primären olfaktorischen Kortex als auch in sekundären olfaktorischen Arealen (Insula, orbitofrontaler Kortex, Cingulum, Hippokampus). Auch wurden größere Volumenabnahmen im Nucleus accumbens mit dem angrenzenden Gyrus subcallosus sowie im dorsolateralen präfrontalen Kortex gefunden. Eine längere Erkrankungsdauer war mit ausgeprägteren Gehirnveränderungen verbunden. VBM ist somit geeignet, Hirnveränderungen bei Patienten mit Riechstörungen darzustellen.
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anosmia leads to a loss of gray matter in cortical brain areas
Chemical Senses, 2010Co-Authors: Thomas Bitter, H P Burmeister, H J Mentzel, Orlando Guntinaslichius, Hilmar Gudziol, Christian GaserAbstract:Chronic olfactory disorders, including the complete loss of the sense of smell (anosmia), are common. Using voxel-based morphometry (VBM) in magnetic resonance imaging (MRI), structural changes in the cerebral gray matter (GM) of a group of patients with anosmia compared with a normosmic, healthy control group were evaluated. Patients with anosmia presented a significant decrease of GM volume mainly in the nucleus accumbens with adjacent Subcallosal Gyrus, in the medial prefrontal cortex (MPC) including the middle and anterior cingulate cortices, and in the dorsolateral prefrontal cortex (dlPFC). These areas are part of the limbic loop of the basal ganglia and except the dlPFC secondary olfactory areas. They also play an important role in many neurological diseases. Furthermore, volume decreases in smaller areas like the piriform cortex, insular cortex, orbitofrontal cortex, hippocampus, parahippocampal Gyrus, supramarginal Gyrus, and cerebellum could be seen. Longer disease duration was associated with a stronger atrophy in the described areas. No local increases in the GM volume could be observed. A comparison with results of an additionally executed functional MRI study on olfaction in healthy subjects was performed to evaluate the significance of the observed atrophy areas in cerebral olfactory processing. To our knowledge, this is the first study on persisting structural changes in cortical GM volume after complete olfactory loss.
H J Mentzel - One of the best experts on this subject based on the ideXlab platform.
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Volumenänderungen der grauen Hirnsubstanz bei Anosmikern: Erkenntnisse durch voxelbasierte Morphometrie
HNO, 2011Co-Authors: Thomas Bitter, H P Burmeister, H J Mentzel, Hilmar Gudziol, Christian Gaser, Orlando Guntinas-lichiusAbstract:Alterations in the central nervous system in patients with a loss of sense of smell are well documented for the olfactory bulb (OB). Here we present a voxel-based morphometry (VBM) study on cerebral alterations in the gray matter of patients with anosmia above the OB. 3-Tesla MRI datasets were obtained from 17 patients with anosmia as well as from 17 normosmic controls. Data processing and evaluation was performed using the SPM5 software package (Wellcome Department of Imaging Neuroscience Group, London, UK) and the implemented VBM5 tool-box. Patients with anosmia showed a significant volume decrease in the gray matter in the primary olfactory cortex as well as in secondary olfactory areas (insular cortex, orbitofrontal cortex, cingulate cortex and hippocampus). Furthermore, volume decreases in areas like the nucleus accumbens with adjacent Subcallosal Gyrus and the dorsolateral prefrontal cortex were found. Longer disease duration was associated with more profound alterations in the gray matter. VBM is appropriate to document brain alterations in patients with olfactory disorders.
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Volumenänderungen der grauen Hirnsubstanz bei Anosmikern
HNO, 2011Co-Authors: T. Bitter, H J Mentzel, Hilmar Gudziol, Christian Gaser, H.p. Burmeister, Orlando Guntinas-lichiusAbstract:Alterations in the central nervous system in patients with a loss of sense of smell are well documented for the olfactory bulb (OB). Here we present a voxel-based morphometry (VBM) study on cerebral alterations in the gray matter of patients with anosmia above the OB. 3-Tesla MRI datasets were obtained from 17 patients with anosmia as well as from 17 normosmic controls. Data processing and evaluation was performed using the SPM5 software package (Wellcome Department of Imaging Neuroscience Group, London, UK) and the implemented VBM5 toolbox. Patients with anosmia showed a significant volume decrease in the gray matter in the primary olfactory cortex as well as in secondary olfactory areas (insular cortex, orbitofrontal cortex, cingulate cortex and hippocampus). Furthermore, volume decreases in areas like the nucleus accumbens with adjacent Subcallosal Gyrus and the dorsolateral prefrontal cortex were found. Longer disease duration was associated with more profound alterations in the gray matter. VBM is appropriate to document brain alterations in patients with olfactory disorders. Veränderungen des zentralen Nervensystems nach einem Verlust des Riechvermögens wurden bisher vor allem für den Bulbus olfactorius (OB) beschrieben. Wir stellen eine Studie zu voxelbasierter Morphometrie (VBM) vor, die Hirnveränderungen bei Patienten mit Anosmie in dem OB übergeordneten Arealen darstellt. Datensätze von 17 Patienten mit Anosmie sowie von 17 normosmischen Kontrollpersonen wurden auf einem 3-T-Magnetresonanztomographen aufgezeichnet. Die Datenverarbeitung und Auswertung erfolgte mit der SPM5-Software (Wellcome Department of Imaging Neuroscience Group, London, UK) und der hierin implementierten VBM5-Toolbox. Die Patientengruppe zeigte eine signifikante Volumenabnahme der grauen Hirnsubstanz sowohl im primären olfaktorischen Kortex als auch in sekundären olfaktorischen Arealen (Insula, orbitofrontaler Kortex, Cingulum, Hippokampus). Auch wurden größere Volumenabnahmen im Nucleus accumbens mit dem angrenzenden Gyrus subcallosus sowie im dorsolateralen präfrontalen Kortex gefunden. Eine längere Erkrankungsdauer war mit ausgeprägteren Gehirnveränderungen verbunden. VBM ist somit geeignet, Hirnveränderungen bei Patienten mit Riechstörungen darzustellen.
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anosmia leads to a loss of gray matter in cortical brain areas
Chemical Senses, 2010Co-Authors: Thomas Bitter, H P Burmeister, H J Mentzel, Orlando Guntinaslichius, Hilmar Gudziol, Christian GaserAbstract:Chronic olfactory disorders, including the complete loss of the sense of smell (anosmia), are common. Using voxel-based morphometry (VBM) in magnetic resonance imaging (MRI), structural changes in the cerebral gray matter (GM) of a group of patients with anosmia compared with a normosmic, healthy control group were evaluated. Patients with anosmia presented a significant decrease of GM volume mainly in the nucleus accumbens with adjacent Subcallosal Gyrus, in the medial prefrontal cortex (MPC) including the middle and anterior cingulate cortices, and in the dorsolateral prefrontal cortex (dlPFC). These areas are part of the limbic loop of the basal ganglia and except the dlPFC secondary olfactory areas. They also play an important role in many neurological diseases. Furthermore, volume decreases in smaller areas like the piriform cortex, insular cortex, orbitofrontal cortex, hippocampus, parahippocampal Gyrus, supramarginal Gyrus, and cerebellum could be seen. Longer disease duration was associated with a stronger atrophy in the described areas. No local increases in the GM volume could be observed. A comparison with results of an additionally executed functional MRI study on olfaction in healthy subjects was performed to evaluate the significance of the observed atrophy areas in cerebral olfactory processing. To our knowledge, this is the first study on persisting structural changes in cortical GM volume after complete olfactory loss.
