Cryogen Spray Cooling for Spatially Selective Photocoagulation of Biological Tissues

在激光的许多治疗应用中，希望诱导表面下目标结构的光热破坏而不损伤覆盖的组织。 例如，某些皮肤疾病如鲜红斑痣（PWS）和血管瘤的成功激光治疗需要选择性破坏表面下靶向血管，同时保护正常的覆盖皮肤结构免受热损伤。 拟议研究的目的是开发和优化冷冻剂喷雾冷却（CSC），以提供短喷射的冷冻剂（毫秒级），结合激光照射，以保护浅表皮肤结构免受热损伤，同时实现表面下靶向血管的光热破坏。 CSC结合激光照射的进一步发展将为对利用激光或其他辐射源在多层复合结构中诱导空间选择性热损伤的治疗程序感兴趣的研究者提供大量相关数据。 该建议的具体目标是：1）开发数学模型以帮助优化CSC和激光照射参数; 2）分别使用胶原膜和鸡冠模型进行体内和体内实验，以验证数学建模的准确性，并证明CSC与激光照射结合用于空间选择性热损伤的实用性; 4）设计和构造紧凑且便携的原型仪器，以：a）允许通过光纤输送冷冻剂和激光;以及B）在选择适当的CSC和激光照射参数之前执行确定目标血管的深度的诊断测量;和5）在哈维穆德学院（HMC）工程系的生物和生物医学工程（BBME）浓度的扩大。 上述任务将通过共同努力来完成 与位于欧文市的加州大学贝克曼激光研究所和医疗诊所（BLIMC）合作 （UCI）。 BLIMC的科学家将合作开发一种诊断程序，以确定深度或地下发色团。 此外，BLIMC还提供了成功完成拟议研究所需的设施和仪器。 教育目标将通过学生参与算法和仪器开发，体外实验来实现。 该项目的跨学科性质将允许在HMC的BBME课程，将包括生物医学光学，传热，激光组织相互作用，生物医学仪器和数值优化技术等主题的教育材料的开发。 ***

9634110 Anvari In many therapeutic applications of lasers, it is desirable to induce photothermal destruction of subsurface targeted structures without damaging the overlying tissue. For example, successful laser treatment of certain skin disorders such as port wine stains (PWS), and hemangiomas requires selective destruction of subsurface targeted blood vessels while protecting the normal, overlying skin structures from thermal injury. The objective of the proposed research is development and optimization of cryogen spray cooling (CSC) to deliver short spurts of a cryogen (on the order of milliseconds) in conjunction with laser irradiation to protect superficial skin structures from thermal injury, while achieving photothermal destruction of subsurface targeted blood vessels. Further development of CSC in conjunction with laser irradiation will provide substantial relevant data to investigators interested in therapeutic procedures utilizing the laser or other radiative sources to induce spatially selective thermal damage in multi-layered composite structures. The specific objectives of this proposal are: 1) development of mathematical models to assist in optimization of CSC and laser irradiation parameters; 2) in-vivo, and in-vivo experimentation using collagen film and chicken comb models, respectively, to verify accuracy of the mathematical modeling, and demonstrate utility of CSC in conjunction with laser irradiation for spatially selective thermal damage; 4) design and construction of a compact, and portable prototype instrument to: a) allow delivery of cryogen and laser light through an optical fiber; and b) perform diagnostic measurements that determine depth of targeted blood vessels prior to selection of appropriate CSC and laser irradiation parameters; and 5) expansion of the Bio- and Biomedical-Engineering (BBME) concentration at Harvey Mudd College (HMC) engineering department. The preceding tasks will be accomplished through a joint effort with the Beckman Laser Institute and Medical Clinic (BLIMC) at University of California, Irvine (UCI). Scientists at BLIMC will collaborate on the development of a diagnostic procedure to determine depth or subsurface chromophores. Furthermore, facilities and instrumentation necessary for successful completion of the proposed research are available at BLIMC. The educational objectives will be achieved by student participation in algorithm and instrumentation development, in-vitro experimentation. The interdisciplinary nature of the project will allow development of educational materials for BBME courses at HMC that would include such topics as biomedical optics, heat transfer, laser-tissue interactions, biomedical instrumentation, and numerical optimization techniques. ***