Gottlieb C, Moffat F, Hagmann M, Babij T, Abitbol A, Lewin A, Houdek P, Schwade J
Department of Radiation Oncology, University of Miami School of Medicine, FL 33101.
J Microw Power Electromagn Energy. 1990;25(3):149-60. doi: 10.1080/08327823.1990.11688123.
Ultra miniature coaxial cable has been used, with microscopic techniques, to fabricate interstitial hyperthermia applicators having diameters of 0.20 mm, 0.33 mm, and 0.58 mm; commercial applicators have a diameter of 1.1 mm. Animal studies with the 0.33 mm diameter applicators have shown that they produce less local tissue trauma than the larger-diameter devices. All of these applicators operate at 915 MHz and have similar heating patterns because they use the conventional monopole design and the catheters have been approximately scaled to the dimensions of each size applicator. We have measured the heating (SAR) patterns of these applicators in tissue-simulating phantoms, both singly and in arrays, using a miniature electric field probe. As an intermediate step to patient trials, we have examined the ability of these applicators to provide effective heating of perfused tissue, using pig thigh and liver as models. Test results suggest that the durability and power handling capabilities of our submillimeter applicators are adequate for use in patients. These new applicators should be useful in the percutaneous treatment of deep-seated tumors and in intraoperative treatments. The applicators also permit intraluminal or intravascular access to tumors.
超微型同轴电缆已与显微技术一起用于制造直径为0.20毫米、0.33毫米和0.58毫米的组织间热疗施源器；商用施源器的直径为1.1毫米。对直径0.33毫米的施源器进行的动物研究表明，与较大直径的设备相比，它们产生的局部组织创伤更小。所有这些施源器均在915兆赫频率下工作，并且具有相似的加热模式，因为它们采用传统的单极设计，且导管已根据每种尺寸施源器的尺寸进行了大致缩放。我们使用微型电场探头在组织模拟体模中单独和以阵列形式测量了这些施源器的加热（比吸收率）模式。作为患者试验的中间步骤，我们以猪大腿和肝脏为模型，研究了这些施源器对灌注组织进行有效加热的能力。测试结果表明，我们的亚毫米级施源器的耐用性和功率处理能力足以用于患者。这些新型施源器应可用于深部肿瘤的经皮治疗和术中治疗。这些施源器还允许通过腔内或血管内途径进入肿瘤。
