LeGUI

LeGUI localizes intracranial electrodes by coregistering postimplant CT to preoperative MRI, detecting surface and depth electrodes, and assigning anatomical targets to support intracranial EEG studies and epilepsy localization.

Key Features:

• Coregistration: Coregisters postimplant CT scans with preoperative MRI to align electrode positions with anatomy.
• Normalization: Normalizes MRI data to the Montreal Neurological Institute (MNI) template.
• Automated Electrode Detection: Automatically detects multiple electrode types including surface and depth/penetrating intracranial electrodes.
• Electrode Spacing Correction and Projection: Performs electrode spacing correction and projects electrodes onto the brain surface for precise localization.
• Electrode Labeling and Anatomical Targeting: Labels detected electrodes and assigns anatomical targets for each electrode location.
• Implementation: Implements core image processing in MATLAB using the Statistical Parametric Mapping (SPM) toolbox.
• Validation: Tested on 51 datasets; automatic detection correctly identified 4362 of 4695 electrodes with 71 false positives, anatomical targeting matched neuroanatomist assignments for 94% of 482 locations, and typical processing time is approximately one hour per dataset.

Scientific Applications:

• Epilepsy localization: Identifying seizure foci in epilepsy patients using intracranial EEG electrode localization.
• Cognitive neuroscience: Interpreting intracranial EEG results in cognitive studies by providing anatomical electrode assignments.
• Intracranial electrophysiology: Providing anatomical localization for intracranial electrophysiology research and clinical analyses.

Methodology:

Computational methods explicitly include CT–MRI coregistration, MRI normalization to the MNI template, automated detection of surface and depth electrodes, electrode spacing correction and projection onto the brain surface, and electrode labeling/anatomical targeting implemented in MATLAB with the SPM toolbox.