Transurethral ultrasound array for prostate thermal therapy: Initial studies
Transurethral ultrasound array for prostate thermal therapy: Initial studies
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DOI：
10.1109/58.542046
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发表时间：
1996-11-01
影响因子：
3.6
通讯作者：
Burdette, EC
中科院分区：
文献类型：
--
作者：
Diederich, CJ;Burdette, EC
本研究介绍了一种用于经尿道超声热疗（TUST）前列腺组织治疗良性前列腺增生（BPH）和癌症的施源器的初步评价。一个管状的多换能器治疗器，包括四个压电陶瓷管（直径2.5毫米，6毫米长，6.8兆赫）在单独的功率控制下，设计成适合在一个半柔性的水冷温度调节输送导管内放置在前列腺尿道治疗期间，超声模式进行了调整，以产生功率沉积，避免非靶组织，如直肠。计算机模拟表明，1.4-2.0 cm径向治疗区（温度大于或等于50-55摄氏度，热剂量大于或等于300 EM（43）），同时保留尿道粘膜，可以在前列腺组织内产生，血液灌注高达10 kg m（-3）s（-1），原型施加器的声分布和功率输出测量已经证明，每个扇形换能器段接近10 W的声功率水平是可达到的，其中波束轮廓在换能器长度内准直并且具有期望的周向分布，这些经尿道施用器的体内热剂量测定表征表明，在50和90摄氏度之间的治疗温度是可达到的，在纵向和圆周方向上是可控的，并且具有有效的径向加热。这些结果清楚地表明，经尿道超声施加器具有比现有的用于前列腺的热疗和热凝固治疗的经尿道热疗技术提供改进的空间定位和加热分布控制的潜力。
This study presents the initial evaluation of an applicator designed for transurethral ultrasound thermotherapy (TUST) of prostate tissue in the treatment of benign prostatic hyperplasia (BPH) and cancer. A tubular multitransducer applicator, consisting of four piezoceramic tubes (2.5 mm diameter, 6 mm long, 6.8 MHz) under separate power control, was designed to fit within a semiflexible water-cooled temperature-regulated delivery catheter to be placed within the prostatic urethra during therapy, Sonication patterns were tailored to produce power depositions which avoid nontargeted tissues, such as the rectum. Computer simulations have demonstrated that 1.4-2.0 cm radial therapeutic zones (temperatures greater than or equal to 50-55 degrees C, thermal doses greater than or equal to 300 EM(43)) with concurrent sparing of the urethral mucosa can be produced within prostate tissue having blood perfusion as high as 10 kg m(-3) s(-1) within 15-30 min. Acoustic distributions and power output measurements of a prototype applicator have demonstrated acoustic power levels approaching 10 W per each sectored transducer segment are attainable, with beam profiles collimated within the transducer length and with desired circumferential distributions, In vivo thermal dosimetry characterizations of these transurethral applicators have indicated that therapeutic temperatures between 50 and 90 degrees C are attainable, controllable in the longitudinal and circumferential directions, and have effective radial heating, These results clearly indicate that transurethral ultrasound applicators have potential to provide improved spatial localization and control of the heating distribution over existing transurethral thermal therapy techniques for both hyperthermia and thermal coagulative therapy of the prostate.