Brain diffusion tensor imaging in dogs with degenerative myelopathy.

Area of Science:

• Veterinary neurology
• Neuroimaging
• Comparative medicine

Background:

• Degenerative myelopathy (DM) in dogs shares similarities with human amyotrophic lateral sclerosis (ALS).
• Diffusion tensor imaging (DTI) is used to quantify brain microstructural lesions in ALS patients.

Purpose of the Study:

• To characterize brain neurodegenerative changes in DM-affected dogs using DTI.
• To assess the utility of DTI as a potential imaging biomarker for DM.

Main Methods:

• A prospective observational study included 16 DM-affected dogs and 8 control dogs.
• Brain DTI was performed at baseline and every 3 months, with diffusion indices calculated on specified regions of interest.
• Gait scores were assigned, and DTI values were compared between groups, correlated with gait scores, and evaluated over time.

Main Results:

• No significant differences in DTI indices were found in brain or spinal cord regions between DM-affected dogs and controls, even after accounting for age.
• DTI values showed poor correlation with gait scores (R² < 0.2).
• No significant longitudinal changes in diffusion indices were detected over time.

Conclusions:

• Brain DTI indices did not differentiate DM-affected dogs from controls.
• DTI did not detect longitudinal changes or correlate with disease severity in DM-affected dogs.
• Current findings do not support the use of brain DTI as an imaging biomarker for degenerative myelopathy in dogs.