(N27) Viability of Using Diffusion Tensor Imaging to Detect Structural Abnormalities in Dogs with Idiopathic Epilepsy

Abstract: Background – Idiopathic epilepsy (IE), a common breed specific disease in dogs, affects cortical white matter connectivity. This can be studied using diffusion tensor magnetic resonance imaging (DTI) by measuring fractional anisotropy (FA).

Hypothesis/Objectives – To determine whether DTI identifies abnormalities in the genu and splenium of the corpus callosum in dogs with IE. The hypothesis predicted a significant difference in FA of healthy dogs (HD) and dogs with IE (IE) who were either responsive to anti-seizure drugs (IE+) or resistant (IE-).

Animals – Thirteen Nova Scotia Duck Tolling Retrievers: 3 HD, 5 IE+, and 5 IE-.

Methods – Retrospective observational study design: FA of the genu and splenium was acquired by hand-drawing regions of interest determined by consensus between researchers’ blind to animal groupings. ANOVA compared FA means between groups. Levene’s test examined variance.

Results – Age was a confounding variable, r = 0.74, P = 0.02. No differences in mean FA were identified; for the splenium, P = 0.0993. Variance in the genu between HD and IE was P = 0.0535.

Conclusions and Clinical Importance – This exploratory study had fewer HD than IE and was confounded by age. Two questions were highlighted for future investigations: Mean FA in the splenium or other white matter regions and variance distribution patterns between HD and IE. A larger sample size with age matched groups would be needed to determine true differences.