CarThéra, Brain and Spine Institute, Pitié Salpêtrière Hospital, 47-83 Boulevard de l'Hôpital, 75013 Paris, France.
J Acoust Soc Am. 2013 Aug;134(2):1647-55. doi: 10.1121/1.4812883.
Interstitial thermal therapy is a minimally invasive treatment modality that has been used clinically for ablating both primary and secondary brain tumors. Here a multi-element interstitial ultrasound applicator is described that allows for increased spatial control during thermal ablation of tumors as compared to existing clinical devices. The device consists of an array of 56 ultrasound elements operating at 6 MHz, oriented on the seven faces of a 3.2 mm flexible catheter. The device was first characterized using the acoustic holography method to examine the functioning of the array. Then experiments were performed to measure heating in tissue-mimicking gel phantoms and ex vivo tissue samples using magnetic resonance imaging-based thermometry. Experimental measurements were compared with results obtained using numerical simulations. Last, simulations were performed to study the feasibility of using the device for thermal ablation in the brain. Experimental results show that the device can be used to induce a temperature rise of greater than 20 °C in ex vivo tissue samples and numerical simulations further demonstrate that tumors with diameters of greater than 30-mm could potentially be treated.
间质内热疗是一种微创治疗方式,已用于消融原发性和继发性脑肿瘤。本文描述了一种多单元间质超声热疗探头,与现有的临床设备相比,该探头可在肿瘤热消融过程中实现更高的空间控制。该探头由 56 个工作在 6MHz 的超声单元组成,排列在一个 3.2mm 柔性导管的七个面上。首先使用声全息法对该探头进行了特性描述,以检查阵列的工作情况。然后,使用基于磁共振成像的测温技术在组织模拟凝胶体模和离体组织样本中进行了加热测量实验。将实验测量结果与数值模拟结果进行了比较。最后,还进行了数值模拟研究,以探讨该探头在脑内热消融中的可行性。实验结果表明,该探头可用于使离体组织样本的温度升高超过 20°C,数值模拟进一步表明,直径大于 30mm 的肿瘤可能可以得到治疗。