A numerical study is performed to translate the MRI induced ex-vivo heating in a stent measured in tissue mimicking gel phantoms to heating in vivo. The in vivo heating was simulated by solving the convective energy equation in a tissue perfused with a single blood vessel embedded with a stent. Appropriate power density function was determined by matching the ex-vivo heating results in the tissue with no blood flow. The effect of the blood flow on the in vivo heating was investigated by varying the flow. Results show that ≥3% of normal, mean physiologic flow in the blood vessel reduces the maximum temperature change to < 3 °C from ∼10 °C measured ex vivo for an MRI scan of ≤ 15 minutes. Local temperature change of up to 3 °C in the trunk is considered safe by the regulatory bodies. Also, the maximum temperature change was found to be ∼1 cm away from the stent ends — and not at the stent ends.

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