Radionuclide stent system aided for intravascular irradiation

假性内膜增生引起的再狭窄或闭塞是支架植入包括动脉或TIPS道在内的管腔的一个棘手问题。在体外，我们研究了使用铱192源的表面剂量的l2Gy血管内照射，特别参考了铱192 ERAD在弯曲血管模型中的等剂量曲线。采用新开发的双闭塞球囊导管原型，可将含铱192源的柔性导管放置在管腔中心，获得最佳等剂量曲线。对34例舌癌患者行高剂量率铱192放射治疗。对于肿瘤包膜、TIPS、动脉粥样硬化性狭窄或动脉瘤患者，也采用Walistents或meadows血管支架植入术。这些结果提示应用这种双球囊导管和含192铱源的柔性导管的组合进行血管内放疗的临床技术可能性。现在进行了一项实验研究，以评估除血管壁本身外辐照血管周围组织的安全性。

Restenosis or occlusion with pseudointimal hyperplasia is a troublesome problem in stenting lumen including arteries or TIPS tract. In vitro, we investigated endovascular irradiation with a surface dose of l2Gy using an Iridium 192 sources, with special reference to Isodose curves of a iridium 192 ERAD in a curved vessel model. Using a newly developed the prototype double occlusion balloon catheter that enabled to place the flexible catheter induding iridium 192 sources in the center of the lumen, optimal isodose curves were obtained. Iridium 192-high dose rate radiotherapy was carried out for the 34 patients with tongue cancer. Endovascular stenting using Walistents or Meadox vascular stent graft was also made for the patients with tumor encasement, TIPS, atherosclerotic stenosis or aneurysm. These results suggest the clinical technical possibility of application of intravascular radiotherapy using this combination of a double balloon catheter and a flexible catheter including 192 Iridium sources. An experimental study is now made to evaluate the safety of the surrounding tissue of the irradiated vessel in addition to the vessel wall itself.