Assessment of MR-Induced Heating Effects in Four Common Veterinary Implants at 1.5 and 3.0 T: A Phantom Study

Quantitative evaluation of implant-related heating in magnetic resonance imaging (MRI) is well standardized in human medicine, whereas evidence in veterinary medicine remains scarce. To address this gap, we measured radiofrequency (RF)-induced heating of four used veterinary implants under controlled conditions on clinical 3.0 and 1.5 T MRI, using an American Society for Testing and Materials (ASTM) F2182-19e2-informed gel phantom manufactured to approximate a 10 kg dog. The test set comprised an identification microchip, a titanium alloy tibial plateau leveling osteotomy (TPLO) plate, a stainless-steel TPLO plate, and an ameroid constrictor. Temperature-time data were acquired with fiber-optic probes, and temperature change was calculated relative to baseline for each replicate run. Maximum temperature rise and heating rate were derived at the run level, with heating rate estimated from the slope of the linear regression of ΔT over time. At 3.0 T, the mean maximum ΔT was 0.300°C for the titanium alloy TPLO plate, 0.300°C for the stainless-steel TPLO plate, 0.467°C for the ameroid constrictor, and 0.500°C for the microchip. At 1.5 T, the corresponding values were 0.067°C, 0.067°C, 0.100°C, and 0.200°C. All individual run-level maximum ΔT values remained ≤0.8°C. Heating rates were small in absolute magnitude, with the microchip ranking highest across field strengths. These findings indicate that, when appropriate imaging parameters are used, MRI-induced heating for the implants examined is unlikely to pose a clinical risk. Future work should broaden device coverage, evaluate off-center placements, vary B₁ conditions, test higher load sequences, and extend assessment to other safety endpoints to refine veterinary-specific MRI safety guidance.