Figure 8

Experimental stent’s temperature under the rf irradiation. (a) The time-dependent stent’s temperature under irradiation at different average power levels \( \overline{P}\kern0.5em = 0.1,\ 0.3,\ 1,\ \mathrm{and}\ 3\ \mathrm{W} \) (denoted on the graph). The initial stent temperature was 19.5°C. At each higher power level, the temperature has reached a new steady-state temperature ΔT higher than the initial temperature. The dashed box encloses the time-dependent temperature increase of the stent for the initial average power \( \overline{P}\kern0.5em = 0.1\ \mathrm{W} \) and is shown expanded in panel (b). The experimental data in the panel (b) (thin black curve) were reproduced theoretically by the exponential function of Equation 8 (thick green curve) with the fit parameters given in the text. The irradiation by the rf pulses on the time axis began at the point marked by an arrow.