上海交通大学
硕士学位论文
皮肤生物组织光热响应研究
姓名：***
申请学位级别：硕士
专业：光学工程
指导教师：***
三年级语文期末试卷20080101
皮肤生物组织光热响应研究
丝袜花的做法摘 要
随着激光生物医学的进展，光辐射在生物组织体中的分布以及光与组织的相互作用成为重要的基础问题，
赵文卓主演的电视剧
并促使了一门新的学科“组织光学”的诞生。上世纪80年代“选择性光热解效应”机理的提出，使得激光在皮肤美容外科方面的应用研究迅速开展起来，然而，至今基础研究仍然远滞后于临床应用，尤其在辐射曝光剂量的选择上，临床上仍带有很大的盲目性与试探性，使得激光或强脉冲复合光的安全性及有效性难以保证，这一问题成为长期困扰广大医师的症结所在。
本文结合数值分析及实验手段，紧紧围绕“皮肤生物组织光热响应”这一命题进行研究，积极探索生物组织的光热作用规律，探求辐射曝光剂量及其参数选择、评价的依据，来提高激光或强脉冲复合光的安全性及有效性。
首先概述了光与生物组织作用的基本机制及生物组织中光传输、热传输的基本理论。
在此基础上，根据皮肤组织吸收光能进而诱发热效应的特点，结合人皮肤组织等的光学特性参数，采用蒙特卡罗方法模拟了皮肤等几种组织中的光能流传输分布，并比较了各个特性参数对光能流分布的影响。
然后采用有限元方法，对含有激光热源项的生物传热方程进行求解，着重定量分析了不同曝光剂量参数（脉宽、脉冲间隔）下皮肤组织的温度分布响应特性，建δ，很好的评价与描述了脉冲光的传热特性，并探究了脉宽及脉冲间立了评价函数
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隔的选取问题，有助于临床上曝光剂量的选取。创新的提出强脉冲复合光的建模模型与方法，并采用有限元方法进行了数值建模分析。
实验部分主要包括两方面的内容，其一：皮肤组织的光谱特性实验。选用与人皮肤组织接近的离体猪皮及皮肤模拟液（脂肪乳剂、碳素墨水），分别研究了它们的光谱特性，得到了散射性粒子与吸收性粒子不同的光谱特性，并以血液（散射、吸收并存）为例进行了验证。其二：皮肤组织的光热响应实验。自行设计并研制了适用于生物软组织体内二维精确定位的热电偶探针测温及单片机温度采集系统，该系统定位精度高（可达10um），两维方向易于调节。并使用该系统，研究了离体猪皮在激光、Nd:YAG激光及强脉冲光作用下的升温特性，并与有限元模拟的结果进行
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结婚证丢了怎么补
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了对比，实验结果与数值模拟结果具有较好的一致性。也说明了数值分析结果的合理性及其具有较好的临床应用价值。
本文工作得到了国家自然科学基金（No.60678054）的资助支持。
关键词：皮肤组织，辐射曝光剂量，蒙特卡罗方法，有限元方法，强脉冲复合光，光谱特性，生物组织温度测量
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OPTICAL-THERMAL RESPONSE RESEARCH OF SKIN
TISSUE
ABSTRACT
With the development of laser medicine, the distribution of laser propaga-tion in the biology tissue and the interaction between laser and tissue have become very important research topics. A new subject called 'tissue optics' has thus been motivated. Since the seminal work of R. R Anderson and J. A Parrish on 'selective photothermolysis effect' in 1980s, the laser techniques have been widely applied to skin hairdressing and treatment. However, the theory research, especially on how to set the light irradiation exposal dose, has been far behind the clinic applications. In practice, the light irradiation exposal dose is set blindly and tentatively in a sense which usually leads to the problems of security and validity.
To solve the problem above, this dissertation aims to find the principal of optical-thermal interaction of biology tissues and thus to give some rules to set the light irradiation exposal dose and exposal parameters (pulse width, pulse interval, etc.) by using experimental design and numerical analysis methods.
In the dissertation, the basic theory work, including the interaction be-
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tween the light and biology tissues, the light propagation and the heat trans-mission in tissues, are introduced firstly.
Next, according to the characteristic that skin absorbs light induced ther-mal effect, Monte Carlo method is adopted to simulate and analyze the light distribution in the skin under different optical parameters.
Then, a finite-element method (FEM) is employed to simulate the skin’s optical-thermal response, focusing on the analysis of selection about light ir-radiation exposal dose and exposal parameters. An evaluation function δis thus established to evaluate the loss of heat. Based onδ, the selection of
pulse width and pulse interval is studied. These results are helpful to guide the selection of exposure parameters, such as pulse width and pulse interval, etc. In addition, the model of intense pulsed light (IPL) is put forward for the first time and is analyzed using FEM.
中国梦作文600字The experimental study includes two aspects. Firstly, the spectrum char-acteristic experiment of skin tissue is studied. The porcine skin is chosen to be the sample for its similar characteristic with human skin, tissue-simulating phantoms (intralipid, india ink) as well. Their spectrums are analyzed and then the different spectrum characteristic between scattering particle and ab-sorbing particle is achieved. Using blood’s spectrum, which contain these two kinds of particle, validate this verdict. Secondly, the optical-thermal response
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