Volumetric Studies

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Volumetric Studies
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Current Technology

• Image Acquisition
• 1.5 Tesla GE scanner, 1 coronal SPGR, 1 axial
  Double Echo PD and T2w image.
• Rigid Registration
• Mutual Information Alignment.
• Brain Segmentation
• Expectation Minimization Segmentation in 4 tissue
  classes (White, Gray, CSF and Face).
• Manual Segmentation of Regions Of Interests.
• Statistical Analysis of the ROIs Volume.

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3D Slicer

• Segmentation
• Level set
• Fast Marching
• EM
• Registration
• Rigid
• Non Linear
• 3D modeling
• Filtering
• Visualisation

http//www.slicer.org
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Brain Segmentation
W. Wells
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Posterior Superior Temporal Gyrus (STG)
Red Left, Green Right Amygdala. Yellow
Left, Light Blue Right Hippocampus (Hipp.).
Orange Left, Dark Blue Right
Parahippocampal Gyrus (PHG). Dark Pink Left,
Purple Right
L. Post. STG
L. STG
Hipp.
PHG
L. Amygdala.
L. Ant. STG
L. Post. STG
L. Hipp.
Hirayasu et al.
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Volumetric Studies Findings

• Lateral Ventricles CSF Enlargement.
• Parietal Volume Reduction.
• Temporal Lobe Volume Reductions
• Amygdala-Hippocampal Complex, Parahippocampal
  Gyrus, Superior Temporal Gyrus.
• Prefrontal Volume Reduction.
• Basal Ganglia (Caudate, Putamen, Globus Pallidus)
  increases and decreases.

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Volumetric Studies
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Shape Global Measures
J. Levitt and C.F. Westin
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Shape Surface Based Analysis
H.J. Park and J. Levitt
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Shape Medial Representations
J. Levitt and S. Bouix
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Technical Challenges

• Image Quality and Acquisition Sequences.
• Multi Channel Atlas Based Segmentation.
• Multi Channel Image Registration.
• Model Based Segmentation.
• Shape Analysis.
• Cortical Thickness.