Directional power deposition from direct-coupled and catheter-cooled interstitial ultrasound applicators.
Directional power deposition from direct-coupled and catheter-cooled interstitial ultrasound applicators.
复制标题
来自直接耦合和导管冷却间质超声探头的定向功率沉积。
DOI：
10.1080/026567300285330
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Stauffer,PR
中科院分区：
文献类型：
--
作者：
Nau,WH;Diederich,CJ;Stauffer,PR
这项研究代表了对间质超声施用器的定向功率沉积能力的实验研究，该施用器旨在用于癌症或良性疾病的热疗和热手术。直接耦合和导管冷却超声探头是使用圆柱形压电陶瓷换能器制造的，该换能器被划分为 900、1800 或 2700 个有效声学区域。通过测量脱气水中的声功率输出和强度光束分布、灌注肾脏模型的体外温度测量以及猪大腿肌肉的体内温度分布来表征施加器。在水中获得的角功率沉积模式与在灌注肾脏和体内猪大腿肌肉中测量的结果温度分布密切相关。这些扇形导管冷却和直接耦合设备都展示了在持续高功率输出水平 (6-12W) 下产生高温 (>500C) 的能力，而不会降低超声换能器的性能。通过体外和体内实验中相应的温度分布以及有角度的热损伤，验证了扇形超声探头能量沉积的方向控制。这一点很重要，因为它表明可以用间质超声探头控制角范围内的加热，从而通过将热能引导到目标组织中来提供更适形的热治疗，同时保护非目标组织免受热损伤。
This research represents an experimental investigation of the directional power deposition capabilities of interstitial ultrasound applicators intended for applications in hyperthermia and thermal surgery for cancerous or benign disease. Direct-coupled and catheter-cooled ultrasound applicators were fabricated using cylindrical piezoceramic transducers sectored to produce 900, 1800or 2700active acoustic zones. The applicators were characterized through measurements of acoustic power output and intensity beam distributions in degassed water,in vitrotemperature measurements in a perfused kidney model, andin vivotemperature distributions in pig thigh muscle. The angular power deposition patterns obtained in water were closely correlated to the resultant temperature distributions measured in the perfused kidney andin vivopig thigh muscle. These sectored catheter-cooled and direct-coupled devices both demonstrated the ability to generate high temperatures (>500C) at sustained high power output levels (6-12W) without degradation of the ultrasound transducers. Directional control of the energy deposition from the sectored ultrasound applicators was verified with corresponding temperature profiles in both thein vitroandin vivoexperiments, as well as with angularly shaped thermal lesions. This is significant in that it demonstrates that heating in the angular expanse can be controlled with interstitial ultrasound applicators, thus providing more conformal thermal therapy by directing the thermal energy in the targeted tissue while protecting non-targeted tissue from thermal damage.