Goals of Presurgical Planning Identify focus (epilepsy surgery) Identify focus (epilepsy surgery) Maximize surgical resection Maximize surgical resection Avoid functionally eloquent cortex and white matter tracts Avoid functionally eloquent cortex and white matter tracts –INDISPENABLE FOR FUNCTION –IF INJURED OR REMOVED- FUNCTIONAL DEFICIT
Functionally Eloquent Cortex Essentials of Anatomy & Physiology, Seeley
Functional MRI Color Overlay of Statistical Maps on Anatomical Images Color Overlay of Statistical Maps on Anatomical Images
Readouts Location of activation 3D extent of activation Distance of border of activation cluster to lesion Laterality index of language (Lt vs Rt) Based upon signal magnitude change
QIBA fMRI Subcommittee New Claims: A. On a test-retest basis, fMRI can be performed reproducibly to a level such that the center of mass of activation of a focus of interest is within 5mm of itself, with at least 90% overlap of the activation clusters. B. On a test-retest basis, fMRI can be performed reproducibly to a level such that the relative magnitude of activation in homologous regions across hemispheres should be within 10%. C. Quantitative measures of “risk” to eloquent brain structures… distance metrics… etc.
Where do we go from here? Create a roadmap to refine claims Assess test-retest reprod multisite by using ASFNR to develop a harmonized approach across institutions Level stratification of claims –Ideal – may require additional info –Target - majority –Acceptable - min competency
Next Steps Mine FBIRN, ADNI, QIBA FDG-PET in conf calls Develop phantom to calibrate T2* change and fSNR. Assess geometric spatial accuracy with B Field mapping to correct geometric distortion Enroll our “customers” in telecon or stand alone meeting Extending readouts to other contexts for use such as neuropsychiatric, neurodegenerative, pharmacologic
Thanks! Dan Sullivan Jeff Evelhoch Madeline McCoy