2018 ACVIM Forum Research Abstract Program: Seattle, Washington, June 14 - 15, 2018

These three relative measurements had good specificity (94.5%, 86.9%, 98.9% respectively), lower sensitivity (80.0%, 66.7%, 60.0%) and were not influenced by body weight (p > 0.05). Absolute measurements (e.g. absolute dens length, atlantoaxial distance) were significantly correlated with body weight (p < 0.05) and their utility in the diagnosis of AA instability could not be established. Decreased C1-C2 overlap strongly supports AA instability. The ADI/DADI ratio, relative dens length and C1-C2 angle may provide further support but may be normal in individual cases. mean pre trial seizure frequency for both groups was calculatedgroup 1: 1 seizure every 9 days; group 2: 1 seizure every 7 days. The overall mean post trial seizure frequency for both groups was decreased. Group 1: 1 seizure every 16 days; group 2: 1 seizure every 9 days. Side effects were limited, with 1 dog experiencing an increase in seizure frequency and 1 dog displaying negative aversive behavior when the device was applied.