Regional ADC values of the morphologically normal canine brain

Area of Science:

• Veterinary Neurology
• Neuroimaging
• Canine Medicine

Background:

• Diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) are vital for diagnosing canine brain diseases.
• Limited data exists on normal canine brain ADC values in large clinical populations.

Purpose of the Study:

• To establish reference ADC values for various anatomical regions in morphologically normal canine brains.
• To investigate the influence of patient factors (sex, age, weight) on canine brain ADC.
• To compare ADC values between gray and white matter, and between cerebral hemispheres.

Main Methods:

• Retrospective analysis of brain MRI studies (2015-2020) from 321 dogs.
• Inclusion of morphologically normal brains from dogs with and without neurological signs.
• Measurement of ADC values in 25 regions of interest (ROIs) across both hemispheres and the cerebellar vermis.

Main Results:

• Significant variations in ADC values were observed across different canine brain anatomical regions.
• Gray matter exhibited significantly higher ADC values (median 0.79 × 10^-3 mm²/s) compared to white matter (median 0.70 × 10^-3 mm²/s).
• Age showed a correlation with ADC values, with decreases in younger dogs and increases in older dogs (≥8 years). No consistent differences were found between sexes or hemispheres.

Conclusions:

• This study provides comprehensive ADC reference data for 25 ROIs in 321 normal canine brains within a clinical context.
• ADC values differ significantly by brain region and are influenced by age-related maturation and aging processes.
• The established data serves as a valuable reference for future clinical research and diagnostic imaging of canine brain conditions.