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An MRI atlas of the human cerebellum in Talairach space
ABSTRACTS
AN MRI ATLAS OF THE HUMAN CEREBELLUM IN TALAIRACH SPACE. Jeremy D. Schmahmann 1,2, Julien Doyon 3,4, Colin Holmes 3,4, Nikos Makris 2, Michael Petrides 3,4, David Kennedy 2, Alan C. Evans 3,4. 1. Department of Neurology and 2. Center for Morphometric Analysis, Massachusetts General Hospital, Boston, MA, 02114; 3. McConnell Brain Imaging Center, Montreal Neurologic Institute and McGill University, Montreal, Quebec, Canada; 4. ICBM Project
Background: There is currently no comprehensive and accurate atlas of the human cerebellum. This has made it difficult to perform detailed correlations of anatomy, function, and pathology. The activation of the cerebellum in functional neuroimaging studies of both motor and nonmotor tasks has emphasized the need for the development of reliable anatomical landmarks. Using MRI, we have developed a comprehensive atlas of the human cerebellum within Talairach space. Methods: The
brain of a healthy young male was imaged using a 1.5 Tesla Philips ACS III magnetic resonance imaging scanner. Twenty-seven T1 weighted images were obtained within the Talairach coordinates (see Holmes et al., this meeting). Brain slices of 0.5mm thickness were co-registered in the sagittal, axial and coronal planes: Using available published data, each cerebellar fissure was identified on the midsagittal section and then followed to its most lateral extent in the parasagittal plane. The location of the fissures was verified on the coronal and axial sections when necessary. Once the fissures were identified, the lobules and sublobules were marked accordingly. The cerebellar nuclei were also identified, although their definition was less clear than that of the folia and fissures.
Results: Eleven major cerebellar fissures were readily identified. The precentral, preculminate, intraculminate, primary, superior posterior, horizontal, ansoparamedian, prepyramidal/prebiventer, intrabiventer, secondary, and posterolateral fissures were all marked on the three planes of section with reliable clarity. The ability to change between the planes of section was a major aid in the localization of some sulci. The horizontal fissure was best seen in more lateral sections, the primary fissure optimally seen in the midsagittal plane. It was apparent that crus I of the ansoparamedian lobe consisted of two elaborate folia which were easily distinguished from each other. On account of the reliable presence and prominence of the previously unnamed fissure between crus IA and crus IB, we called it the "crus I internal fissure." After defining the fissures, it was possible to identify the various cerebellar lobules, sublobules, and subfolia, particularly when comparing the different planes of section. Conclusions: We developed a detailed atlas of the human cerebellum within the Talairach coordinate system in a single brain using MRI. The ability to change between the sagittal, coronal and axial planes of section in 0.5 mm slices provided a reliable and valid method for interpretation of the anatomic landmarks of the cerebellum. This will be a critical tool for the accurate localization of cerebellar lesions in clinical-pathologic correlation studies. It will also be valuable in the determination of cerebellar anatomic-functional correlations for functional neuroimaging. Additionally, it will serve as a template for further morphometric studies such as the development of probabilistic maps and the parcellation of the human cerebellum.
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AN MRI ATLAS OF THE HUMAN CEREBELLUM IN TALAIRACH SPACE. Jeremy D. Schmahmann 1,2, Julien Doyon 3,4, Colin Holmes 3,4, Nikos Makris 2, Michael Petrides 3,4, David Kennedy 2, Alan C. Evans 3,4. 1. Department of Neurology and 2. Center for Morphometric Analysis, Massachusetts General Hospital, Boston, MA, 02114; 3. McConnell Brain Imaging Center, Montreal Neurologic Institute and McGill University, Montreal, Quebec, Canada; 4. ICBM Project
Background: There is currently no comprehensive and accurate atlas of the human cerebellum. This has made it difficult to perform detailed correlations of anatomy, function, and pathology. The activation of the cerebellum in functional neuroimaging studies of both motor and nonmotor tasks has emphasized the need for the development of reliable anatomical landmarks. Using MRI, we have developed a comprehensive atlas of the human cerebellum within Talairach space. Methods: The
brain of a healthy young male was imaged using a 1.5 Tesla Philips ACS III magnetic resonance imaging scanner. Twenty-seven T1 weighted images were obtained within the Talairach coordinates (see Holmes et al., this meeting). Brain slices of 0.5mm thickness were co-registered in the sagittal, axial and coronal planes: Using available published data, each cerebellar fissure was identified on the midsagittal section and then followed to its most lateral extent in the parasagittal plane. The location of the fissures was verified on the coronal and axial sections when necessary. Once the fissures were identified, the lobules and sublobules were marked accordingly. The cerebellar nuclei were also identified, although their definition was less clear than that of the folia and fissures.
Results: Eleven major cerebellar fissures were readily identified. The precentral, preculminate, intraculminate, primary, superior posterior, horizontal, ansoparamedian, prepyramidal/prebiventer, intrabiventer, secondary, and posterolateral fissures were all marked on the three planes of section with reliable clarity. The ability to change between the planes of section was a major aid in the localization of some sulci. The horizontal fissure was best seen in more lateral sections, the primary fissure optimally seen in the midsagittal plane. It was apparent that crus I of the ansoparamedian lobe consisted of two elaborate folia which were easily distinguished from each other. On account of the reliable presence and prominence of the previously unnamed fissure between crus IA and crus IB, we called it the "crus I internal fissure." After defining the fissures, it was possible to identify the various cerebellar lobules, sublobules, and subfolia, particularly when comparing the different planes of section. Conclusions: We developed a detailed atlas of the human cerebellum within the Talairach coordinate system in a single brain using MRI. The ability to change between the sagittal, coronal and axial planes of section in 0.5 mm slices provided a reliable and valid method for interpretation of the anatomic landmarks of the cerebellum. This will be a critical tool for the accurate localization of cerebellar lesions in clinical-pathologic correlation studies. It will also be valuable in the determination of cerebellar anatomic-functional correlations for functional neuroimaging. Additionally, it will serve as a template for further morphometric studies such as the development of probabilistic maps and the parcellation of the human cerebellum.
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