LONI: Laboratory of Neuro Imaging

Research Milestones

ICBM project has initiated full scale production activities to complete the structural aspects of data acquisition. All key centers in the program have upgraded their imaging equipment which has now been commissioned and calibrated for use in this effort. These upgrades occurred at all data acquisition sites. As a result, a number of accomplishments have been achieved and are noted below.

  • An optimal structural MRI protocol has been developed for newly installed Siemens instruments using the MPRAGE pulse sequence. This has been optimized with regard to signal to noise characteristics of the structural images both with regard to superficial structures such as the cortex as well as for deep structures such as the thalamus and basal ganglia.
  • The development of probabilistic white matter tract maps is now fully underway. Following an extensive period of testing different protocols that focused on the number of directions of data acquisition required, number of repetitions in order to maximize signal to noise properties in the images and availability of pulse sequence algorithms, Dr. Mori of Johns Hopkins University has finalized the protocol for these studies which are now about to begin at a production level at all participating sites.
  • The ICBM template brain, available at http://www.loni.usc.edu/atlases/
    Atlas_Detail.php?atlas_id=5, has been the source of frequent downloads. With this tool, an MRI study obtained anywhere can be warped to match the anatomically labeled template brain and then transformed back to its original shape with each voxel carrying a probabilistic anatomical label.
  • We have completed a number of studies to provide pilot data for the automated segmentation of MR angiograms and venograms. Studies in individual subjects using phase contrast MRA and MRV with and without gadolinium contrast, have provided an important data set that is being used to tune algorithms for use in the segmentation of vascular anatomy in the human brain.
  • We have successfully merged and registered cytoarchitectonic probabilistic maps and fMRI data for language tasks involving Broca's region. These efforts have demonstrated the specific components within Broca's area that are cytoarchitectonically linked to functional tasks.
  • We have completed the first registration of probabilistic cytoarchitectonic maps and magneto-encephalography studies in the visual system.
  • We completed the first neuroreceptor PET study examining serotonin (5-HT2A) receptors using PET and probabilistic maps of cytoarchitectonic cortical regions. These were also related to post mortem tritium labeled ketanserin autoradiographs for multiple cytoarchitectural areas.
  • Serotonin receptor ligand binding methods have been completed by our colleagues in Jülich including the detailed metabolite analysis of this compound paving the way for production studies at the participating sites. This work will result in the first in vivo receptor probabilistic maps with important implications for studies in patients with depression, other affective disorders and psychiatric syndromes.
  • ICBM MRI data sets have been used worldwide for algorithm development. These data sets, collected in the pre-HIPAA era, have been requested and delivered to sites throughout the world for use in testing algorithms for image segmentation, normalization and other important aspects of anatomical brain analyses using MRI data.