Meeting Banner
Abstract #0815

Using Reliability to Predict Validity in Clinical FMRI

Tynan Reid Stevens1, Steven D. Beyea1, Ryan CN D'Arcy1, David B. Clarke2

1IBD-Atlantic, NRC, Halifax, Nova Scotia, Canada; 2QEII Health Science Centre, Halifax, Nova Scotia, Canada

The accuracy of presurgical fMRI is inherently related to the threshold method used to create the activation maps. We aim to demonstrate that choosing thresholds that optimize reproducibility leads to high correspondence with the gold standard, cortical stimulation (CS). Eleven patients were tested by presurgical fMRI, and observed while CS was performed in the operating room. Functional MRI maps were optimized for reliability, and the distance from each CS point to the nearest activated voxel was calculated. Reliability optimization reduced the CS-to-fMRI distance by 1-8 mm compared with traditional threshold methods.

Abstract PDF

Keywords

accurately achieved activated activation active affine allow alone arrest asked automated best blocks blue brain buttons care categorize caused ceiling central clinical common components comprehension consisted control correct corrected correlation cortical critical curve days decreases despite digit digital digitized disruption distance distances either eleven elicited errors establish example feather finger fixed flash function functional hand identified included incorrect john language localization locations mapping masking matrix motor mouth move movement name naming nearest nova objects onto optimal optimized pair part passively patient patients patterns peak performance photograph placed positive potentially predict prior production purple recorded reduced reducing reduction reliable remaining reproducibility required respectively response rest retest scanners science sensations sensory sentence sentences served sessions setting shapes shot simultaneously smoothed statements stimulation stimuli stroked structural subjects subtraction success suggests supporting surgery surgical system tags tapping task tasks template threshold thresholding thresholds tongue tool transformation treatment tumors valid validity vary view volume year zones