High Intensity Ultrasound in Gastroenterology

描述(申请人提供)：急性消化道出血是治疗性内窥镜检查的常见指征。有几种内窥镜止血方法可用，包括热疗(加热器探头、电灼术、Ar等离子凝固术和激光)、注射疗法和机械装置(带状结扎、夹子和可拆卸的环)。虽然有几种治疗胃肠道出血的装置和方法，但对于大出血、恶性溃烂肿瘤出血和胃肠壁深处血管出血等情况，止血装置的开发仍需取得进展。高强度聚焦超声(HIFU)是治疗胃肠道出血的一种新方法。对组织施加HIFU可导致HIFU换能器焦点内的温度在1秒内迅速上升至100xC，而不会损害中间组织。这种热效应是由于像放大镜聚焦太阳光一样聚焦超声束，使组织在小焦点体积内吸收声波能量所致。HIFU已被证明可以在动物模型上实现动脉和静脉被刺穿的止血，该模型被认为是由于热凝。我们对撕裂的兔耳静脉和动脉进行了初步止血研究，表明HIFU可能对急性胃肠道出血有效。建议开发一种适合于HIFU内窥镜输送的探头，随后在大动物胃肠道出血中进行体内研究。预计这项工作将有助于更好地了解HIFU的机制及其在其他胃肠道应用中的潜在作用，如肿瘤治疗。

DESCRIPTION (provided by applicant): Acute GI bleeding is a common indication for therapeutic endoscopy. Several methods of endoscopic hemostasis are available including thermal therapy (heater probes, electrocautery, argon plasma coagulation, and lasers), injection therapy, and mechanical devices (band ligation, clips, and detachable loops). Although several devices and methods for treating gastrointestinal bleeding exist, advances in the development of hemostatic devices are still needed for situations such as massive bleeding, bleeding from malignant ulcerated tumors, and bleeding arising from vessels located deep within the GI wall. High-intensity focused ultrasound (HIFU) represents a new method that may have applications in treating gastrointestinal bleeding. HIFU applied to tissue can result in a rapid rise in temperature approaching 100xC in 1 second within the focus of the HIFU transducer without damaging the intervening tissue. This thermal effect is due to absorption of acoustic energy by tissue in a small focal volume due to focusing of the ultrasound beam similar to a magnifying glass focusing sunlight. HIFU has been demonstrated to achieve hemostasis in punctured arteries and veins in animals models thought to be due to thermal coagulation. We have performed initial hemostasis studies in lacerated rabbit auricular veins and arteries that suggest HIFU may be effective in the treatment of acute GI bleeding. The development of a probe suitable for the endoscopic delivery of HIFU followed by in vivo studies in large animals with GI bleeding is proposed. It is anticipated that this work will help to gain a better understanding of the mechanisms of HIFU and its potential role for other GI applications such as tumor therapy.