Manon Desclides^{1,2,3}, Valéry Ozenne^{1,3,4,5}, Pierre Bour^{2}, Guillaume Machinet^{6}, Christophe Pierre^{6}, Stéphane Chemouny^{2}, and Bruno Quesson^{3,4,5}

^{1}UMR5536 CRMSB, Université de Bordeaux, Bordeaux, France, ^{2}Certis Therapeutics, Pessac, France, ^{3}IHU Liryc, Electrophysiology and Heart Modeling Institute, Hopital Xavier Arnozan, Pessac, France, ^{4}Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, University of Bordeaux, Bordeaux, France, ^{5}INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France, ^{6}ALPhANOV, Talence, France

We present here a method to automatically regulate heat deposition during Laser Interstitial Thermal Therapy to precisely control temperature evolution during the procedure. The method relies on real-time rapid volumetric thermometry using the Proton Resonance Frequency Shift technique and a regulation algorithm that adjusts every second the emitted power by the laser to force temperature to follow a predefined temperature-time profile.

$$T(t) = \left\{\begin{array}{lll}0&\mbox{if } t ≤ t_0\\

αPτ\ln[\frac{t-t_0+τ}{τ}]&\mbox{if } t_0 < t ≤ t_1&\qquad &\text{(Eq.1)}\\

αPτ\ln[\frac{t-t_0+τ}{t-t_1+τ}&\mbox{if } t < t_1 \end{array} \right. $$

where t

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Figure 1: Kalman filter output example on 20 s test shot at 3W temporal temperature profile, with raw temporal pixel temperature profile in blue and its real-time Kalman filter output in red

DOI: https://doi.org/10.58530/2022/2167