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Papademetras . Image-guided Navigation Systems Structural and Functional images registered to patient space Research workstation is interfaced to commercial surgical workstation for Epilepsy surgery Allows stable, reliable system for clinical surgery VVLink now part of BrainLab system

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  • Image-guided Navigation Systems
    • Structural and Functional images registered to patient space
  • Research workstation is interfaced to commercial surgical workstation for Epilepsy surgery
    • Allows stable, reliable system for clinical surgery
    • VVLink now part of BrainLab system
      • Includes ability to track surgical tools
  • Brain Deformation is compensated for by stereo cameras and modeling
  • In cases where surgical resection is not possible, neurostimulators are used (in functionally sensitive areas)
  • How does one leverage prior information from normal controls
  • How do we emphasize robustness over accuracy?
coulon cortical localization and inter subject surface matching
CoulonCortical localization and inter-subject surface matching
  • For morphometric or functional studies of populations
  • Volume-based and sphere transformations have been used in the past
  • Cortical organization based on “sulcal roots” is an alternative model
  • Sulcal landmarks are (semi-automatically?) defined for tranform to standard space
  • Application can be for parcellation of brain anatomy and
  • QUESTIONS: How does one deal with anatomical variability.
    • Can this generalized to maps of brain function (e.g. language defined in surgical stimulation studies
  • Should multiple atlases be developed?
  • See:
clatz modeling brain tumors for patient specific therapy
ClatzModeling brain tumors for patient-specific therapy
  • Tumor growth and mass effects are simulated through computer (linear elastic) models
  • Goal is to use models for patient-specific treatments
leiphart neurosurgery for brain implants
LeiphartNeurosurgery for brain implants
  • Technology for seizure detection

Paradigm shift from exec (localized) center to [network] of anatomically distinct centers

Synchrony precedes 70% of seizures

Advanced algorithms and computation needed to predict seizures (shift from electrocorticog)

  • How does object (face) recognition work?
  • Is there an “Alice Cooper neuron” in the brain?
  • Question: How nonlinear is the fMRI/EEG brain? Is there a functional role for oscillations…?
  • Electrode introduces bias in single neuron recording
  • Active electrode Compensation is a computer model to remove this bias.
  • Message: Model based approaches can extend possibilities of standard electrode recording, for example measuring excitatory and inhibitory synaptic conductance.
  • Physiological noise (nuisance variables) can be removed from fMRI
    • Heart rate
    • Magnetic susceptibility corrections also shown
  • How do we infer interactions in fMRI
    • Motor network is well understood
    • Information exchange between brain units – definition of functional interactions
      • Can this be defined mathematically
      • Can causality be inferred from fMRI?
pessiglione functional imaging pharm challenges
Pessiglionefunctional imaging/pharm challenges
  • DA involved in reward,validated in monkeys, mimicked by engineered models
  • Behavioral experiment in choice experiment rewarded by money (or punished by loss)
  • L-dopa associated with faster learning than Haldol
  • Model/theory ventral striatum associated with critic. Anterior putamen
  • Are [decisions] subconscious?
  • Can brain reading predict decisions?
gaillard epilepsy functional imaging and language
GaillardEpilepsy, functional imaging and language
  • Auditory Description Decision Task (ADDT) fMRI
  • Stroke or epilepsy result in relocation of language function in R hemisphere
  • Exploratory data analysis (no a priori hypothesis) was done in epilepsy pts.
  • Posterior margin of Wernicke’s is utilized
  • Anterior only group vs. anterior and posterior moves to contralateral side
nadja cnmc neuroradiology research national children s center wash dc
NadjaCNMC Neuroradiology ResearchNational Children’s Center, Wash DC
  • MRI scanners, technologies and neuroradiologists available for collab.
  • Areas of ongoing research
    • Craniofacial phenomics, head shape modeling
    • Molecular imaging of pediatric brain tumors
      • Superparamagnetic nanoparticles for MRI and optical fluorescence imaging
    • Tumor volumetry
    • Infant MRS and DTI
    • Fetal MRI and 3D U/S
    • ASL/Susceptibility weighted imaging in stroke (sickle cell)
    • Small animal imaging
michael levene
Michael Levene
  • Multiphoton microscopy
    • Single molecule sensitivity
  • Sub micron resolution
  • Two photon excitation, unlike single, has a single focal point of excitation
  • Near IR light scatters less than blue light
  • Intrinsic fluorescence of UV is possible too
  • Hypometabolism measured in epilepsy with neurosurgeon
    • NADH is fluorescent, NAD is not
  • Long lens might be used to penetrate 3.5 mm of tissue for optical biopsy
  • What are clinical applications for MPM and optical imgs?
olivier david eeg fmri epilepsy
Olivier DavidEEG/fMRI/Epilepsy
  • Small animal up to 7T
  • Human 3T scanner
  • fMRI studies of unilateral epilepsy
  • Rat model (genetic absence
  • fMRI of visual stimulation (thalamic relay)
  • Implanted epileptic patients are used in studies of 1 Hz neurostimulation of hippocampus
  • Antiepileptics studied in animal (rat) models
  • Microelectronics developed for neural implants and adaptive control of epilepsy
  • Stimulation of network may be alternative model for TX
    • Experimental work needed prior to clinical trials
    • Animal studies are vital
christian habeck multivariate neuroimage analysis
Christian HabeckMultivariate neuroimage analysis
  • Univariate stats (SPM) are straightforward parametric and use stringent type-I error correction
  • Multivariate – non-parametric, better suited for distributed analysis
    • data dredging?
  • Covariance analysis of ASL MRI in Alzheimer’s appears to discriminate
  • Multivariate techniques could be used in meta-analyses
  • Where does Multivariate analysis show new insight over univariate analysis?
  • Epiphenomena or does Multivariate analysis really provide insights
thirion group analysis of fmri
ThirionGroup Analysis of fMRI
  • Problems with standard inference
    • Small samples
    • Spatial normalization –precision about 1cm
  • Critical questions
    • Which structures should be studied?
    • How to detect false positives
    • Which structures are cross-correlated?
    • Question: Build an anatomo-functional atlas (integrated and fully Bayesian)
    • Brainvisa software available soon.
baillet time resolved imaging meg eeg
BailletTime resolved imaging MEG/EEG
  • Atlas of basal ganglia might be used for DBS targeting – plug in for Papademetras?
  • Inverse problem – go from signal to map of brain (function, anatomy)
  • What can time perspective bring you for understanding brain function?
    • 400 ms duration map of tennis ball catch
    • Similarly conscious perception moves from visual to ventral processing of information
    • Optical flow (borrowed from weather models) can be used to understand dynamics of brain activity
    • State 1 flows to state 2
  • Challenges: Reduce theory/computational gap
  • Make tools clinically useful tools
  • Richard Leahy USC collaborator