Equine Stereotaxtic Population Average Brain Atlas With Neuroanatomic Correlation

Area of Science:

• Neuroscience
• Comparative Anatomy
• Medical Imaging

Background:

• Horses possess large, complex brains, making them valuable for neuroscientific research and as potential models for neuropsychological diseases.
• Magnetic Resonance Imaging (MRI) is a key tool for in vivo and ex-vivo brain studies.
• A comprehensive equine brain atlas is currently lacking for neuroimaging research.

Purpose of the Study:

• To create a high-resolution, stereotaxic population average brain atlas for the equine species.
• To provide a foundational resource for equine and translational neuroimaging research.
• To document brain volume metrics and assess the influence of age and laterality.

Main Methods:

• Generated a population average brain atlas from nine unfixed equine cadaver brains using 3-tesla MRI within 4 hours of euthanasia.
• Employed linear and non-linear registration methods, with quality assessed via signal-to-noise ratio calculations.
• Created tissue segmentation maps (white matter, gray matter, cerebrospinal fluid) and manually segmented anatomic priors for subcortical structures.

Main Results:

• The equine brain atlas was successfully generated and validated against gross anatomical specimens.
• Mean volume metrics for whole brain, gray matter, and white matter were documented.
• Identified right-sided volume dominance in whole brain, gray matter, and white matter, consistent with known equine forebrain lateralization.

Conclusions:

• The developed equine brain atlas is a crucial, freely available online resource for automated processing in equine and translational neuroimaging.
• The atlas facilitates comparative studies and enhances our understanding of equine brain structure and function.
• Findings on brain volume and laterality contribute to the neurological characterization of the horse.