Comparison of randomized multifocal mapping and temporal phase mapping of visual cortex for clinical use

Area of Science:

• Neuroimaging
• Functional Magnetic Resonance Imaging (fMRI)
• Visual Neuroscience

Background:

• fMRI is crucial for surgical planning in neurosurgery.
• Temporal phase mapping and multifocal stimulation are key paradigms for visual cortex mapping.
• Clinical relevance necessitates evaluating mapping techniques on efficiency, completeness, and noise tolerance.

Purpose of the Study:

• Directly compare temporal phase mapping and multifocal stimulation paradigms.
• Assess clinical utility based on time efficiency, mapping completeness, and noise effects.
• Determine the optimal fMRI mapping strategy for routine clinical applications.

Main Methods:

• Direct comparison of temporal phase and multifocal vision mapping paradigms.
• Evaluation of clinically relevant factors: time efficiency, mapping completeness, and noise effects.
• Analysis of voxel response decomposition and retinotopic assignments under varying noise levels.

Main Results:

• Multifocal mapping accurately decomposed responses and maintained retinotopic assignments with increased noise, despite reduced sensitivity.
• Multifocal mapping efficiency decreased with more stimulus segments and higher duty cycles.
• Temporal phase mapping activated more extrastriate areas, was more time-efficient, and showed better sensitivity with noise, but introduced systematic retinotopic mis-assignments.

Conclusions:

• Temporal phase mapping is generally superior for routine clinical fMRI applications due to its efficiency and sensitivity.
• Multifocal mapping may provide unique benefits for specialized neuroimaging applications.
• The choice of fMRI mapping paradigm should consider clinical needs and potential trade-offs.