Presentation on theme: "The BRAINs Orientation"— Presentation transcript:
1The BRAINs Orientation Siegfried SchreiSiemens MI Applications
2Manual OrientationIn addition, the anterior commisure and posterior commisure are used for the horizontal orientation in the sagittal plane.The standard orientation calls for lining up the interhemispheric fissure. This sets the alignment in the coronal and axial planes.
3Where are the Anterior and Posterior commissure? Positioning of Vertical AC and PC Lines
4Where are the Anterior and Posterior commissure? Positioning of Vertical AC and PC Lines (Spect fix distance)
5Horizontal AC to PC line Horizontal AC - PC Line.
6Rotate Brain to Anterior and Posterior commissure axis Horizontal AC - PC Line.
10Where are the Anterior and Posterior commissure? The perfect alignment:Reperate right and left hemisphereAC – PC line for correct Axial planes
11Coregistration Modalities MRI Image or CT images are co registered to the manually reoriented SPECT or PET image by use E.Soft Image Fusion or Syngo 3D Image registration.Manually aligned by visual matching, surface matching or use of anatomical land marks. By far the preferable method is the fully automated alignment based on Mutual Information co registration.When fitting is complete each MRI image is resampled to the SPECT or PET orientation and resolution (128 x 128 Matrix, ca 5 mm cubic voxels).Point to point correspondence with any given set of coordinates referring to the same point in all of the images
12Talairach BoundsDefine a Talairach-based atlas for the each scan individually (MRI more easy compared to SPECT)Landmarks usedRight-most extent of the brainLeft-most extent of the brainAnterior-most extent of the brainPosterior-most extent of the brainSuperior-most extent of the brainInferior-most extent of the temporal lobeAC and PC locations
13Talairach Atlas Talairach atlas coordinate system Resampled image with overlaid Talairach coordinate system
21Neural Network Currently defines the following regions CaudatePutamenThalamusCerebellumCerebellar lobes (warping)Hippocampus (requires editing)Globus Pallidus (requires editing)In the near future will use a warped method for all structures – more valid, less editingWill also add nucleus accumbens and amygdala
24Cerebellum LobesCerebellar Lobe Volumes: Uses landmark-based warp for semiautomated measurement of Lobes I through V (anterior lobe), Lobe VI and Crus I of VIIA (superior posterior lobe), Crus II of VIIA through Lobe X (inferior posterior lobe), and the central white matter and output nuclei(corpus medullare).
25Talairach Atlas II What about the cerebellum? Not included in Talairach AtlasUsed for automated gross regional measuresProvides a coordinate system for structure probability