Main obstacle to applying current transcranial MR-guided focused ultrasound (tcMRgFUS) to treat TLE is that the medial temporal lobe (MTL) is outside the ‘treatment envelope’ with respect to the base of the skull in current clinically approved devices. Strategies using FUS safely for thermal ablation of the MTL have not been adequately explored. Possible strategies that could also be combined, include; 1) Using lower frequency sonic energy to decrease energy deposition in the boney tissue of the skull. 2) Blocking algorithms to optimize thermal deposition at the target while minimizing skull heating; 3) Longer sonication time with lower sonication power to allow for MTL ablation. We hypothesis that effective combination of the strategies will allow for a safe and robust ablation of MTL. We propose comprehensive investigation to evaluate the feasibility of ablating MTL through simulations and experimental verification.
-Develop and optimize finite element solvers. Simulation tools will allow us to find estimates of optimal power, sonication duration and frequency will be obtained for a balance between the heating of the desired target while minimizing skull heating. Experimental verification will be on skull samples using hydrophone measurements and thermocouples.
-Develop and optimize blocking algorithms combined with power manipulation to reduce peak skull heating while achieving acceptable focus at the MTL. A strategy for power compensation to reduce the skull heating will be applied when the ablative temperature is reached at the target. Experimental validation will be on skull samples and verified on fresh cadavers.