DEVELOPMENT OF THE ENDOVASCULAR THROMBOLYSIS SYSTEM WITH SHOCK WAVE

冲击波血管内溶栓系统的研制

基本信息

批准号：
12307028
负责人：
YOSHIMOTO Takashi
金额：
$ 11.9万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12307028/
关键词：
ENDOVASCULAR INFRARED MONITOR CEREBRAL EMBOLISM ENDOVASCULAR THERAPY SHOCK WAVE ENGINEERING THROMBOLYSIS LASER-INDUCED LIQUID JET LASER MEDICINE VASCULAR ENDOSCOPY 閉塞性脳血管障害衝撃波医療

项目摘要

Background and ObjectiveThere are several problems inherent in the treatment of cerebral embolisms, such as the narrow therapeutic time window and the severe side effects of fibrinolytic drugs. It is thusnecessary to develop a new method of removing a cerebral thrombus more rapidly using smaller amounts of fibrinolytics. In the present, we investigated a liquid jet induced by holmium (Ho) : YAG laser irradiation in water.Materials and MethodsIn this study, a pulsed Ho : YAG laser whose wavelength, pulse duration, and energy were 2.1 μm, 350 μs, and 350 mJ/pulse, respectively. Behavior of Ho : YAG laser induced bubble in a capillary tube filled with pure water was observed at various stand-off distances (L ; distance between the optical fiber end and the capillary exit). After that, a liquid-jet generator was made by insertion of an optical fiber (diameter : 0.6 mm) into a catheter (6Fr) filled with pure water. The maximum penetration depth of a liquid jet generated with this device int … More o a gelatin artificial thrombus was measured at various stand-off distances (L ; destance between the optical fiber end and catheter exit). Moreover, the phenomenon and the pressure around the catheter were observed with a shadowgraph and PVDF needle hydrophon, respectively. Based on these results, a stand-off distance of 13 mm was chosen to investigate the enhancement of urokinase (UK) efficacy by only a single operation of the liquid-jet device in artificial thrombi made of human blood.ResultsA laser-induced bubble in a capillary tube rapidly grew forward and generated a liquid jet. Maximum penetration depth with the liquid-jet generating catheter increased in proportion to L and reached a maximum value (9 mm) when L was around 13 mm. A shock wave whose overpressure at a point several mm away from the catheter exit was over 12MPa was captured with shadowgraph Fabrinolysis rates (%) after incubation with a small amount of UK for 10 min and 30 min were predominantly raised by a single use of the laser-induced liquid jet (5.4 ± 2.4 vs. 22.6 ± 6.1 and 7.3 ± 3.8 vs. 38.3 ± 5.6, respectively (mean ± SD, p<0.001)).ConclusionsHo : YAG laser irradiation within a capillary tube filled with water caused liquid jet formation, which promoted the effect of fibrinolytics. Moreover, this jet was accompanied with shock waves, which might enable to facilitate endovascular balloon angioplasty by cracking subintimal calcified lesions. The liquid jet generation system is so simple that will be applied to an endovascular system for cerebral fibrinolysis in the near future. Less

背景与目的脑栓塞治疗存在治疗时间窗窄、溶栓药物副作用严重等问题，因此有必要开发一种更快速、更少量的溶栓药物清除脑血栓的新方法。目前，我们研究了钬 (Ho) : YAG 激光在水中照射引起的液体射流。材料和方法在本研究中，脉冲 Ho : YAG 激光器波长、脉冲持续时间和能量分别为 2.1 μm、350 μs 和 350 mJ/脉冲。 Ho 的行为：在充满纯水的毛细管中观察到不同距离的 YAG 激光诱导气泡。之后，将光纤（直径：0.6 mm）插入充满纯净物的导管（6Fr）中制成液体喷射发生器。在不同的间隔距离（L；光纤末端和导管出口之间的距离）下测量了该装置在明胶人工血栓中产生的液体射流的最大穿透深度。分别用阴影图和PVDF针水声器观察导管周围的情况，基于这些结果，选择13mm的间隔距离来研究仅通过一次操作即可增强尿激酶（UK）的功效。结果激光诱导的毛细管中的气泡快速向前生长并产生液体射流，液体射流产生导管的最大穿透深度与L成比例增加并达到最大值。 (9mm)，当L为13mm左右时，在距离导管出口几mm的点处的超压超过12MPa的冲击波在用小粒子孵育后用阴影图捕捉到。 10 分钟和 30 分钟的 UK 量主要通过单次使用激光液体诱导喷射而提高（分别为 5.4 ± 2.4 与 22.6 ± 6.1 和 7.3 ± 3.8 与 38.3 ± 5.6（平均值±SD，p< 0.001)). 结论Ho : YAG 激光照射在充满水的毛细管内引起液体射流形成，从而促进了此外，这种射流伴随着冲击波，这可能有助于通过破裂内膜下钙化病变来促进血管内球囊血管成形术，液体射流生成系统非常简单，将在不久的将来应用于脑纤溶的血管内系统。较少的