Velocardiofacial Syndrome as a Genetic Model for Schizophrenia

1
Velocardiofacial Syndrome as a Genetic Model for
Schizophrenia

• Marek Kubicki
• DBP2, Brigham and Womens Hospital, Harvard
  Medical School

2
Team

• HARVARD
• Marek Kubicki, MD, PhD
• Sylvain Bouix, PhD
• Yogesh Rathi, PhD
• Doug Markant, BA
• Usman Khan, BA
• NAMIC
• Polina Golland MIT
• Brad Davis Kitware
• CF Westin BWH
• Others

3
NAMIC Roadmap Project Stochastic Tractography

• Accomplished
• 1. Method successfully used Stochastic
  Tractography
• with old schizophrenia data available to NAMIC
  (1.5T GE
• data) (Shenton et al., 2007).
• 2. Algorithm tested on smaller structures
• (cingulum, uncinate, arcuate, fornix). Data
  presented
• at Santa Fe in October.
• 3. Optimized to work with newly acquired, high
  resolution
• BWH 3T DTI data (available to NAMIC since
  December 2008).
• 4. Algorithm also tested and further debugged on
  phantom data (Programming week).
• 5. New tools added to the module per our
  request cutting
• the tracts at the ROIs, streamline tractography
  option to test
• continuity of the tract.
• 6. Slicer3 module built (programming week).

4
NAMIC Roadmap Project Stochastic Tractography

• Update- Language related connections
• 1. ROIs including Brocka and Wernicke areas
  generated using free surfer
• 2. White matter masks used for tracking purposes
  generated also with free surfer.
• 3. Registration between DTI and MRI done, using
  demons slicer algorythm.
• 4. Tracts for the Arcuate Fasciculus
• extracted, IOFF affected by distortions
• much more, extraction unreliable.

5
NAMIC Roadmap Project Stochastic Tractography

• Outstanding related issues
• 1. Distortion correction needed for the
  registration to be more accurate.
• 2. Or better registration to compensate for the
  distortions.
• 3. Measurements along the extracted tracts
  (automatic tract parametrization, outlier
  rejection?).
• 4. Compatibility with other data formats.

6
Other Projects Update

• DLPFC project
• We have been testing and improving slicer 2 DLPFC
  segmentation module, and optimizing segmentation
  for 3T structural data.
• We have been testing different bias field
  correction programs, in order to further
  fine-tune 3T slicer segmentation.
• Jim Fallon, visited PNL in Spring, and helped
  drawing DLPFC on all cases.
• The problem now seems to be that because the
  sulci are so deep, and do not run parallel to the
  geometric blades, we get inconsistent results. We
  discuss implications of the editing with Jim.

7
Other Contributions to the NAMIC Kit

• Resting state fMRI analysis project
• We have collected resting-state fMRI data, and
  started analyzing it. Preliminary results have
  been presented at Biol Psych.
• Polinas student (Bryce) with help from Jungsu Oh
  runs ICA and GMM (Gaussian Mixture Model) on the
  data now. Some problems with noise handling in
  the data

8
Other Contributions to the NAMIC Kit

• DTI atlas registration project
• We have obtained DTI atlas of white matter labels
  from MIND (Susumu Mori)
• We are trying to register these labels to our 3T
  DTI data through anatomical SPGR images.
  Preliminary data presented at Biological
  Psychiatry Symposium.
• We are using slicer 2, and working on improving
  co-registration procedures (estimating and
  applying deformations to different images,
  reverse deformations, etc). B-spline available,
  in the testing phase.

9
Collaborations within NAMIC
UNC Corpus Callosum Subdivision using tractography-based model (Kubicki et al., paper submitted)
MIT Whole Brain Group Spectral Clustering (new data analysis ongoing)
GaTech Cingulum Bundle analysis using Finsler method (ongoing)
Utah DTI data analysis using atlas building (ongoing)