首页> 外文学位 >An integrated model of heat transfer and tissue freezing for cryosurgery using cryo-spray or cryoprobe.
【24h】

An integrated model of heat transfer and tissue freezing for cryosurgery using cryo-spray or cryoprobe.

机译:使用冷冻喷雾或冷冻探针进行冷冻手术的热传递和组织冷冻的集成模型。

获取原文
获取原文并翻译 | 示例

摘要

Cryosurgery is a novel surgical technique using low temperature and tissue freezing to destroy undesired tissue, especially cancerous tissue. A numerical model of cryosurgery is highly desirable in clinic practice to predict target tissue thermal history, assess treatment outcome and optimize cryosurgical protocol. The present dissertation dedicates to develop an integrated model addressing multiple complex physics involved in cryosurgery, including fluid flow, bioheat transfer and tissue freezing. Extensive and in-depth numerical studies have been conducted for two typical yet distinct cryosurgeries: cutaneous cryosurgery (using liquid nitrogen spray) and hepatic cryosurgery (using liquid nitrogen cryoprobe).; The modeling of cutaneous cryosurgery starts from treating target skin tissue as a homogeneous media. The anatomic structure of human skin tissue is then incorporated by considering three sub-layers: epidermis, dermis and subcutaneous fat. Bioheat transfer during the cryosurgery is described by classic Pennes Equation, while critical modifications are made on the thermal effects of blood perfusion and metabolism according to the physiological characteristics of each sub-layer. The model is then applied to study a general cutaneous cryosurgery and a specific clinic case: the cryosurgery on nodular basal cell carcinoma (BCC). A methodology for quantitatively determining the extent of intracellular ice formation (IIF) based on the tissue temperature and cooling rate (CR) is proposed, followed by systematic parametric study to investigate the effect of various protocol parameters on the final IIF zone. These results contribute to support dermatologists to estimate the treatment outcome in cryosurgery pretreatment planning.; The modeling of hepatic cryosurgery emphasis the heat interaction between the fluid flow of LN2 within a cryoprobe and the surrounding tissue. Laminar flow model and turbulent flow model are all validated and applied to study the effect of LN2 flow on the heat transfer characteristic of the cryoprobe. A conjugate model is eventually developed, which simultaneously addresses the turbulent flow of LN2 within the cryoprobe, bioheat transfer in surrounding hepatic tissue and subsequent tissue freezing. Parametric study is also conducted to investigate the impact of LN2 flow on tissue freezing.
机译:冷冻手术是一种新颖的手术技术,其利用低温和组织冷冻来破坏不希望的组织,特别是癌性组织。在临床实践中,非常需要冷冻手术的数值模型来预测目标组织的热史,评估治疗结果并优化冷冻手术方案。本论文致力于开发一种综合模型,以解决涉及冷冻手术的多种复杂物理问题,包括流体流动,生物热传递和组织冻结。已经对两种典型但截然不同的冷冻手术进行了广泛而深入的数值研究:皮肤冷冻手术(使用液氮喷雾)和肝冷冻手术(使用液氮冷冻探针)。皮肤冷冻手术的建模始于将目标皮肤组织视为均质介质。然后通过考虑三个亚层来整合人体皮肤组织的解剖结构:表皮,真皮和皮下脂肪。经典的Pennes方程描述了冷冻手术期间的生物热传递,同时根据每个子层的生理特征对血液灌注和新陈代谢的热效应进行了重要的修改。然后将该模型用于研究一般的皮肤冷冻手术和特定的临床病例:结节性基底细胞癌(BCC)的冷冻手术。提出了一种基于组织温度和冷却速率(CR)定量确定细胞内冰形成(IIF)程度的方法,然后进行系统的参数研究,以研究各种方案参数对最终IIF区域的影响。这些结果有助于皮肤科医生评估冷冻手术前治疗计划中的治疗结果。肝冷冻外科手术的建模强调了冷冻探针内LN2的液流与周围组织之间的热相互作用。验证了层流模型和湍流模型,并将其用于研究LN2流量对低温探头传热特性的影响。最终开发出一种共轭模型,该模型同时解决了冷冻探针内LN2的湍流,周围肝组织中的生物热传递以及随后的组织冻结问题。还进行了参数研究,以研究LN2流量对组织冻结的影响。

著录项

  • 作者

    Sun, Feng.;

  • 作者单位

    The University of Akron.;

  • 授予单位 The University of Akron.;
  • 学科 Engineering Biomedical.; Engineering Mechanical.; Health Sciences Medicine and Surgery.
  • 学位 Ph.D.
  • 年度 2007
  • 页码 208 p.
  • 总页数 208
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 生物医学工程;机械、仪表工业;
  • 关键词

  • 入库时间 2022-08-17 11:40:13

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号