MRIcron

MRIcron visualizes and analyzes neuroimaging data in NIfTI format to support lesion mapping and voxel-based lesion–symptom analysis.

Key Features:

• Image Viewing and Layering: Loads and overlays multiple NIfTI image layers for comparative inspection of brain anatomy.
• Volume Rendering: Provides volume rendering for three-dimensional visualization of anatomical regions.
• Volume of Interest (VOI) Drawing: Enables drawing and analysis of VOIs/lesions within MRI images for targeted delineation.
• DICOM to NIfTI Conversion (dcm2nii): Includes dcm2nii functionality to convert DICOM images to NIfTI format.
• Statistical Analysis with NPM (Nonparametric Mapping): Integrates the NPM toolbox for voxel-based lesion–symptom analysis and nonparametric statistical testing.
• Mapping to MNI Space: Supports manual mapping and overlay of individual lesions onto the Montreal Neurological Institute (MNI) template.
• Visualization of Statistical Results: Visualizes statistical maps and test results (e.g., Liebermeister test) on the MNI template.

Scientific Applications:

• Voxel-based lesion–symptom mapping: Correlates lesion locations with clinical deficits using voxel-wise nonparametric statistics.
• Lesion mapping in clinical studies: Has been used to map lesions onto MNI space to identify associations between lateral medullary infarction (LMI) and urinary retention/micturition dysfunction.

Methodology:

DICOM-to-NIfTI conversion via dcm2nii; loading and layering of NIfTI volumes; volume rendering; manual VOI/lesion delineation; manual mapping of lesions to the MNI template; integration with NPM for voxel-based lesion–symptom analysis and statistical testing (e.g., Liebermeister test); visualization of results on the MNI template.