The Experts below are selected from a list of 1095 Experts worldwide ranked by ideXlab platform
Dong Soo Lee - One of the best experts on this subject based on the ideXlab platform.
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Assessment of Cerebral Glucose Metabolism in Cat Deafness Model: Strategies for Improving the Voxel-Based Statistical Analysis for Animal PET Studies
Molecular Imaging and Biology, 2008Co-Authors: Jin Su Kim, Jae Sung Lee, Min-hyun Park, Hyejin Kang, Jong Jin Lee, Hyo-jeong Lee, Dae Hyuk Moon, Sang Moo Lim, Dong Soo LeeAbstract:Purpose The aim of this study was to establish the procedures for 3D voxel-based statistical analysis of 2-deoxy-2-[^18F]fluro- d -glucose-positron emission tomography (FDG-PET) images of a cat’s brain obtained using a small animal-dedicated PET system and to assess the utility of this approach in investigating the cerebral glucose metabolism in an animal model of Cortical Deafness. Procedures This study compared several different strategies for the spatial processing of PET data acquired twice from eight cats before and after inducing Deafness in terms of the comparability of the statistical analysis results to the established pattern of the cerebral glucose metabolic changes in the deaf animals. Results The accuracy of the spatial preprocessing procedures and the statistical significance of the comparison were improved by removing the background activities outside the brain regions. The use of the spatial normalization parameters obtained from the mean image of the realigned data set for individual data also helped improve the statistical significance of the paired t testing. It was also found that an adjustment of the registration options was also important for increasing the precision of the realignment. Conclusions A method for voxel-based analysis of the PET data of a cat’s brain was optimized. The results demonstrated the high localization accuracy and specificity of this method, which is expected to be useful for examining the brain PET data of medium-sized animals such as cats.
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Voxel-based statistical analysis of cerebral glucose metabolism in the rat Cortical Deafness model by 3D reconstruction of brain from autoradiographic images
European Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Jae Sung Lee, Soon-hyun Ahn, Dong Soo Lee, Chong Sun Kim, Jae Min Jeong, Kwang Suk Park, June-key Chung, Myung Chul LeeAbstract:Purpose Animal models of Cortical Deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual Deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest. Methods Thirteen 2-[1-^14C]-deoxy- D -glucose autoradiographic images were acquired from six deaf and seven age-matched normal rats (age 6–10 weeks). The Deafness was induced by surgical ablation. For the 3D voxel-based statistical analysis, brain slices were extracted semiautomatically from the autoradiographic images, which contained the coronal sections of the brain, and were stacked into 3D volume data. Using principal axes matching and mutual information maximization algorithms, the adjacent coronal sections were co-registered using a rigid body transformation, and all sections were realigned to the first section. A study-specific template was composed and the realigned images were spatially normalized onto the template. Following count normalization, voxel-wise t tests were performed to reveal the areas with significant differences in cerebral glucose metabolism between the deaf and the control rats. Results Continuous and clear edges were detected in each image after registration between the coronal sections, and the internal and external landmarks extracted from the spatially normalized images were well matched, demonstrating the reliability of the spatial processing procedures. Voxel-wise t tests showed that the glucose metabolism in the bilateral auditory cortices of the deaf rats was significantly ( P
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Voxel-based statistical analysis of cerebral glucose metabolism in the rat Cortical Deafness model by 3D reconstruction of brain from autoradiographic images.
European Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Jae Sung Lee, Soon-hyun Ahn, Dong Soo Lee, Chong Sun Kim, Jae Min Jeong, Kwang Suk Park, June-key Chung, Myung Chul LeeAbstract:Purpose Animal models of Cortical Deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual Deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest.
Jae Sung Lee - One of the best experts on this subject based on the ideXlab platform.
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Assessment of Cerebral Glucose Metabolism in Cat Deafness Model: Strategies for Improving the Voxel-Based Statistical Analysis for Animal PET Studies
Molecular Imaging and Biology, 2008Co-Authors: Jin Su Kim, Jae Sung Lee, Min-hyun Park, Hyejin Kang, Jong Jin Lee, Hyo-jeong Lee, Dae Hyuk Moon, Sang Moo Lim, Dong Soo LeeAbstract:Purpose The aim of this study was to establish the procedures for 3D voxel-based statistical analysis of 2-deoxy-2-[^18F]fluro- d -glucose-positron emission tomography (FDG-PET) images of a cat’s brain obtained using a small animal-dedicated PET system and to assess the utility of this approach in investigating the cerebral glucose metabolism in an animal model of Cortical Deafness. Procedures This study compared several different strategies for the spatial processing of PET data acquired twice from eight cats before and after inducing Deafness in terms of the comparability of the statistical analysis results to the established pattern of the cerebral glucose metabolic changes in the deaf animals. Results The accuracy of the spatial preprocessing procedures and the statistical significance of the comparison were improved by removing the background activities outside the brain regions. The use of the spatial normalization parameters obtained from the mean image of the realigned data set for individual data also helped improve the statistical significance of the paired t testing. It was also found that an adjustment of the registration options was also important for increasing the precision of the realignment. Conclusions A method for voxel-based analysis of the PET data of a cat’s brain was optimized. The results demonstrated the high localization accuracy and specificity of this method, which is expected to be useful for examining the brain PET data of medium-sized animals such as cats.
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Assessment of Cerebral Glucose Metabolism in Cat Deafness Model: Strategies for Improving the Voxel-Based Statistical Analysis for Animal PET Studies
Molecular Imaging and Biology, 2008Co-Authors: Jin Su Kim, Jae Sung Lee, Min-hyun Park, Hyejin Kang, Jong Jin Lee, Hyo-jeong Lee, Dae Hyuk Moon, Sang Moo LimAbstract:Purpose The aim of this study was to establish the procedures for 3D voxel-based statistical analysis of 2-deoxy-2-[18F]fluro-d-glucose-positron emission tomography (FDG-PET) images of a cat’s brain obtained using a small animal-dedicated PET system and to assess the utility of this approach in investigating the cerebral glucose metabolism in an animal model of Cortical Deafness.
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Voxel-based statistical analysis of cerebral glucose metabolism in the rat Cortical Deafness model by 3D reconstruction of brain from autoradiographic images
European Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Jae Sung Lee, Soon-hyun Ahn, Dong Soo Lee, Chong Sun Kim, Jae Min Jeong, Kwang Suk Park, June-key Chung, Myung Chul LeeAbstract:Purpose Animal models of Cortical Deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual Deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest. Methods Thirteen 2-[1-^14C]-deoxy- D -glucose autoradiographic images were acquired from six deaf and seven age-matched normal rats (age 6–10 weeks). The Deafness was induced by surgical ablation. For the 3D voxel-based statistical analysis, brain slices were extracted semiautomatically from the autoradiographic images, which contained the coronal sections of the brain, and were stacked into 3D volume data. Using principal axes matching and mutual information maximization algorithms, the adjacent coronal sections were co-registered using a rigid body transformation, and all sections were realigned to the first section. A study-specific template was composed and the realigned images were spatially normalized onto the template. Following count normalization, voxel-wise t tests were performed to reveal the areas with significant differences in cerebral glucose metabolism between the deaf and the control rats. Results Continuous and clear edges were detected in each image after registration between the coronal sections, and the internal and external landmarks extracted from the spatially normalized images were well matched, demonstrating the reliability of the spatial processing procedures. Voxel-wise t tests showed that the glucose metabolism in the bilateral auditory cortices of the deaf rats was significantly ( P
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Voxel-based statistical analysis of cerebral glucose metabolism in the rat Cortical Deafness model by 3D reconstruction of brain from autoradiographic images.
European Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Jae Sung Lee, Soon-hyun Ahn, Dong Soo Lee, Chong Sun Kim, Jae Min Jeong, Kwang Suk Park, June-key Chung, Myung Chul LeeAbstract:Purpose Animal models of Cortical Deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual Deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest.
Myung Chul Lee - One of the best experts on this subject based on the ideXlab platform.
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Voxel-based statistical analysis of cerebral glucose metabolism in the rat Cortical Deafness model by 3D reconstruction of brain from autoradiographic images
European Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Jae Sung Lee, Soon-hyun Ahn, Dong Soo Lee, Chong Sun Kim, Jae Min Jeong, Kwang Suk Park, June-key Chung, Myung Chul LeeAbstract:Purpose Animal models of Cortical Deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual Deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest. Methods Thirteen 2-[1-^14C]-deoxy- D -glucose autoradiographic images were acquired from six deaf and seven age-matched normal rats (age 6–10 weeks). The Deafness was induced by surgical ablation. For the 3D voxel-based statistical analysis, brain slices were extracted semiautomatically from the autoradiographic images, which contained the coronal sections of the brain, and were stacked into 3D volume data. Using principal axes matching and mutual information maximization algorithms, the adjacent coronal sections were co-registered using a rigid body transformation, and all sections were realigned to the first section. A study-specific template was composed and the realigned images were spatially normalized onto the template. Following count normalization, voxel-wise t tests were performed to reveal the areas with significant differences in cerebral glucose metabolism between the deaf and the control rats. Results Continuous and clear edges were detected in each image after registration between the coronal sections, and the internal and external landmarks extracted from the spatially normalized images were well matched, demonstrating the reliability of the spatial processing procedures. Voxel-wise t tests showed that the glucose metabolism in the bilateral auditory cortices of the deaf rats was significantly ( P
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Voxel-based statistical analysis of cerebral glucose metabolism in the rat Cortical Deafness model by 3D reconstruction of brain from autoradiographic images.
European Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Jae Sung Lee, Soon-hyun Ahn, Dong Soo Lee, Chong Sun Kim, Jae Min Jeong, Kwang Suk Park, June-key Chung, Myung Chul LeeAbstract:Purpose Animal models of Cortical Deafness are essential for investigation of the cerebral glucose metabolism in congenital or prelingual Deafness. Autoradiographic imaging is mainly used to assess the cerebral glucose metabolism in rodents. In this study, procedures for the 3D voxel-based statistical analysis of autoradiographic data were established to enable investigations of the within-modal and cross-modal plasticity through entire areas of the brain of sensory-deprived animals without lumping together heterogeneous subregions within each brain structure into a large region of interest.
Jin Su Kim - One of the best experts on this subject based on the ideXlab platform.
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Assessment of Cerebral Glucose Metabolism in Cat Deafness Model: Strategies for Improving the Voxel-Based Statistical Analysis for Animal PET Studies
Molecular Imaging and Biology, 2008Co-Authors: Jin Su Kim, Jae Sung Lee, Min-hyun Park, Hyejin Kang, Jong Jin Lee, Hyo-jeong Lee, Dae Hyuk Moon, Sang Moo Lim, Dong Soo LeeAbstract:Purpose The aim of this study was to establish the procedures for 3D voxel-based statistical analysis of 2-deoxy-2-[^18F]fluro- d -glucose-positron emission tomography (FDG-PET) images of a cat’s brain obtained using a small animal-dedicated PET system and to assess the utility of this approach in investigating the cerebral glucose metabolism in an animal model of Cortical Deafness. Procedures This study compared several different strategies for the spatial processing of PET data acquired twice from eight cats before and after inducing Deafness in terms of the comparability of the statistical analysis results to the established pattern of the cerebral glucose metabolic changes in the deaf animals. Results The accuracy of the spatial preprocessing procedures and the statistical significance of the comparison were improved by removing the background activities outside the brain regions. The use of the spatial normalization parameters obtained from the mean image of the realigned data set for individual data also helped improve the statistical significance of the paired t testing. It was also found that an adjustment of the registration options was also important for increasing the precision of the realignment. Conclusions A method for voxel-based analysis of the PET data of a cat’s brain was optimized. The results demonstrated the high localization accuracy and specificity of this method, which is expected to be useful for examining the brain PET data of medium-sized animals such as cats.
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Assessment of Cerebral Glucose Metabolism in Cat Deafness Model: Strategies for Improving the Voxel-Based Statistical Analysis for Animal PET Studies
Molecular Imaging and Biology, 2008Co-Authors: Jin Su Kim, Jae Sung Lee, Min-hyun Park, Hyejin Kang, Jong Jin Lee, Hyo-jeong Lee, Dae Hyuk Moon, Sang Moo LimAbstract:Purpose The aim of this study was to establish the procedures for 3D voxel-based statistical analysis of 2-deoxy-2-[18F]fluro-d-glucose-positron emission tomography (FDG-PET) images of a cat’s brain obtained using a small animal-dedicated PET system and to assess the utility of this approach in investigating the cerebral glucose metabolism in an animal model of Cortical Deafness.
Kimitaka Kaga - One of the best experts on this subject based on the ideXlab platform.
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An unperceived acoustic stimulus decreases reaction time to visual information in a patient with Cortical Deafness
Scientific Reports, 2020Co-Authors: Anthony N. Carlsen, Dana Maslovat, Kimitaka KagaAbstract:Responding to multiple stimuli of different modalities has been shown to reduce reaction time (RT), yet many different processes can potentially contribute to multisensory response enhancement. To investigate the neural circuits involved in voluntary response initiation, an acoustic stimulus of varying intensities (80, 105, or 120 dB) was presented during a visual RT task to a patient with profound bilateral Cortical Deafness and an intact auditory brainstem response. Despite being unable to consciously perceive sound, RT was reliably shortened (~100 ms) on trials where the unperceived acoustic stimulus was presented, confirming the presence of multisensory response enhancement. Although the exact locus of this enhancement is unclear, these results cannot be attributed to involvement of the auditory cortex. Thus, these data provide new and compelling evidence that activation from subCortical auditory processing circuits can contribute to other Cortical or subCortical areas responsible for the initiation of a response, without the need for conscious perception.
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A case of Cortical Deafness and loss of vestibular and somatosensory sensations caused by cerebrovascular lesions in bilateral primary auditory cortices, auditory radiations, and postcentral gyruses - complete loss of hearing despite normal DPOAE and
Acta Oto-Laryngologica, 2015Co-Authors: Kimitaka Kaga, Yukiko Shinjo, Chieko Enomoto, Mitsuko ShindoAbstract:AbstractConclusion: A right-handed 38-year-old man’s complete loss of hearing could be diagnosed as Cortical Deafness caused by cerebral vascular lesions in bilateral auditory cortices. Objective: The aim of this case report was to study the pathophysiology of a particular patient who manifested Deafness without residual hearing and lost somatosensory sensation, vestibular sensation, and articulation ability after a right internal carotid-posterior communicating artery (IC-PC) aneurysm and subarachnoidal hemorrhage. Methods: MRI, aphasia and neurological tests, subjective and objective audiometry, and vestibular function tests were performed. Results: The neurological test revealed system loss of somatosensory sensation with normal motor function and articulation ability. Brain imaging revealed extensive infarction in the bilateral primary auditory cortices, postcentral gyruses, and the bilateral partial third frontal gyruses. Pure-tone audiometry of both ears revealed off-the-scale results and speech aud...
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Environmental Sound Perception in Patients with Cochlear Implants Compared with That in Patients with Auditory Nerve Diseases (Auditory Neuropathy) and Cortical Deafness
Neuropathies of the Auditory and Vestibular Eighth Cranial Nerves, 2009Co-Authors: Kimitaka Kaga, Yusuke AkamatsuAbstract:The mechanism for perception of environmental sounds is considered to be different from the cognitive mechanism of language. The environmental sound perception of cochlear implantees appears to be good but not perfect. However, its underlying mechanism is not yet known. The aim of this study was to investigate perception of environmental sounds in postlingually deaf patients with cochlear implants compared with that in patients with central auditory disorders. Seventeen postlingual patients with cochlear implants, 6 patients with auditory nerve disease (auditory neuropathy), and 10 patients with Cortical Deafness were selected for the comparison. A tape-recorded environmental sound perception test of 24 environmental sounds, which was developed by the authors in 1987, was used. This test is divided into two categories: the category of vocalization includes human voice as well as animal and bird sounds, and the category of non-voice sounds includes sounds of nature and musical instruments, as well as sounds from man-made sources. The test procedure consists of two steps. The fi rst step (open set) is only to listen and to identify each sound either orally or in writing. The second step (closed set) is to listen and chooses a picture card matching test form among four different pictures. The percentages of correctly identifi ed environmental sounds in postlingually deaf patients with cochlear implants was markedly higher than that in patients with Cortical Deafness, but was similar to that in patients with auditory nerve disease (auditory neuropathy), in both the closed and open sets. Our study revealed that the perception of environmental sounds in postlingual patients with cochlear implants was not good in the open set but markedly better in the closed set. This result is similar to those for auditory nerve disease patients but completely different from those for Cortical Deafness patients. The ability of patients with cochlear implants to perceive environmental sounds is similar to that of patients with auditory nerve disease, perhaps because information carried by the cochlear nerve is similarly degraded.
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A case of Cortical Deafness and anarthria
Acta Oto-Laryngologica, 2004Co-Authors: Kimitaka Kaga, Masako Nakamura, Yoshihiro Takayama, Hiromitsu MomoseAbstract:Generally, Cortical Deafness is not complicated by anarthria and Cortical anarthria does not affect auditory perception. We report a case of simultaneous progressive Cortical Deafness and anarthria. At the age of 70 years, the patient, a woman, noticed hearing problems when using the telephone, which worsened rapidly over the next 2 years. She was then referred to our hospital for further examinations of her hearing problems. Auditory tests revealed threshold elevation in the low and middle frequencies on pure-tone audiometry, a maximum speech discrimination of 25% and normal otoacoustic emissions and auditory brainstem, middle- and long-latency responses. An articulation test revealed abnormal pronunciation. Because of these problems only written and not verbal communication was possible; her ability to read and write was unimpaired. She showed no other neurological problems. Brain MRI demonstrated atrophic changes of the auditory cortex and Wernicke's language center and PET suggested low uptake of (18F...
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Environmental sound perception in adult patients with cochlear implants: a comparison with central auditory disorders.
Cochlear implants international, 2004Co-Authors: Kimitaka Kaga, Yusuke Akamatsu, Erika Ogata, Masae Shiroma, Sinichi Ishimoto, Ken Ito, Tatsuya YamasobaAbstract:The aim of this study is to investigate the perception mechanism of environmental sounds in postlingual patients with cochlear implants compared with that in patients with central auditory disorders. Seventeen postlingual patients with cochlear implants were studied; six patients with auditory nerve disease (auditory neuropathy) and ten patients with Cortical Deafness were selected for the comparison. A taperecorded environmental sound perception test of 24 environmental sounds was carried out. This test is divided into two categories: the category of voice includes human voice, animal and bird sounds, and the category of non-voice includes musical instrument sound, natural sound and artificial sound. The percentage of correct perception of environmental sounds in postlingually deaf patients with cochlear implants was markedly higher than that in patients with Cortical Deafness, but was similar to that in patients with auditory nerve disease (auditory neuropathy).
