Finite volume analysis of temperature effects induced by active MRI implants with cylindrical symmetry: 1. Properly working devices

Table 2 Data for calculation of power density P_V according to Eq. (7) for an MRI sequence with an SAR of 4 W/kg (manufacturer declaration)

permeability of vacuum	μ ₀	[V s / (A m)]	12.6E-7
magnitude of magnetic excitation field	B₁	[μ T]	25
repetition time of MRI sequence	TR	[s]	2.23
duration of one excitation	τ	[ms]	0.80
number of identical excitations during TR	N		246
duty cycle c_dc = N τ/TR	c_dc		0.09
pulse waveform modulation factor c_pwm	c_pwm		0.45
Larmor frequency = resonance frequency of LC circuit	ν ₀	[MHz]	63.8
power loss density P_V = P/(Q V_imp) (Eq. (7)	P_V	[mW/(cm³Q)]	4.0

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