Laser manufacturing distal-end-optical-systems for endoscopic optical-biopsy diagnostics

用于内窥镜光学活检诊断的激光制造远端光学系统

• 批准号: ST/M007839/1
• 负责人: Robert Thomson
• 金额: $ 36.52万
• 依托单位: Heriot-Watt University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FM007839%2F1
• 关键词: Laser; manufacturing; distal; end; optical

Oesophageal cancer has the fastest rate of increase of any cancer in the developed world and a poor prognosis with low survival after five years. Early identification of changes in oesophageal tissue leads to improved prognosis, but current techniques rely on traditional endoscopy and biopsy, which are invasive and exhibit poor sampling, and are only capable of identify issues that have already manifested through changes in the cellular structure. Recent developments in photonic-based technologies mean that it is now feasible to develop a medical diagnostic that is capable of identifying pre-cancerous (Barrett's syndrome), cancerous and non-cancerous tissues, by analysing the spectral properties of laser light inelastically scattered from tissue (Raman spectroscopy). By performing Raman spectroscopy at the end of a thin and flexible fibre-optic, that is used to precisely guide light into and out from the region of interest, it will be possible to test in-vivo whether oesophageal tissue is malignant or normal. This technique may also be able to pick up abnormalities that would not be picked up during histopathology, crucial information that could enable early diagnosis and mean that unnecessary invasive surgical procedures could be avoided. Such a technology would also find applications in the endoscopic treatment of Barrett's oesophagus and oesophageal cancer, enabling the clinician to assess the margins of the relevant tissue regions before and during resection.There is, however, a significant manufacturing issue that stands in the way of fully developing these new and exciting photonic-based clinical tools; in order to control the properties of the light leaving and entering the distal (in-vivo) end of the fibre-optic, it is necessary to use a distal-end-optical-system (DOS) of some form. This DOS can be as simple as a single lens, or a more complicated construction, requiring mirrors, spectral filters and lenses, as is the case in the optical-biopsy Raman-based instrument. Currently, manufacturing such DOS devices requires discrete micro-optic components to be aligned and bonded together. These techniques are labour intensive, time-consuming and expensive. In short, current DOS fabrication techniques are non-optimal and are not suitable to commercial manufacturing; a new and more flexible manufacturing technique is required.During this STFC-CLASP project, we will develop new DOS manufacturing processes using ultrafast laser based techniques. These processes use focused ultrashort laser pulses, each only a few hundred femtoseconds long, to locally and precisely modify the structure of a substrate material in three-dimensions. The laser-induced modification manifests itself in a variety of ways, examples of which include changes to the chemical etch-rate and/or refractive index of the modified material. Using these manifestations, it is possible to directly write optical components, such as diffraction gratings, into the substrate material, and by using a post-irradiation chemical-etch step we can sculpt precision micro-optics. The fact that "ultrafast laser inscription" enables micro-optic components, such as lenses, mirrors and optical waveguides to be combined onto a single substrate, using a single manufacturing process, makes it the ideal route to commercially manufacture precision DOS technologies.

食道癌在发达国家中的任何癌症的增加率最快，预后较差，五年后生存率较低。早期鉴定食道组织的变化会导致预后的改善，但是当前的技术依赖于传统的内窥镜检查和活检，这些内窥镜检查和活检表现出侵入性和抽样较差，并且只能识别通过细胞结构变化而表现出的问题。基于光子的技术的最新发展意味着，现在可以通过分析从组织中散布的激光散布的激光频谱（拉曼光谱）来鉴定能够鉴定出癌前（巴雷特综合症），癌性组织和非癌组织的医学诊断。通过在薄且柔性的光纤末端进行拉曼光谱法，该光谱可以准确地从感兴趣的区域引导光线进入和流出，可以在体内测试食道学组织是否具有恶性或正常。该技术也可能能够拾取在组织病理学期间不会拾取的异常，至关重要的信息可以实现早期诊断，并意味着可以避免不必要的侵入性手术程序。这种技术还将在对巴雷特食管和食道癌的内窥镜治疗中找到应用，使临床医生能够评估切除之前和期间相关组织区域的边缘。为了控制纤维光线的远端（体体）远端（体内）的属性，有必要使用某种形式的远端末端 - 光学系统（DOS）。该DOS可以像单个镜头一样简单，也可以是更复杂的结构，需要镜子，光谱过滤器和镜头，就像光学生物基于拉曼的仪器中一样。当前，制造此类DOS设备需要将离散的微观组件对齐并键合在一起。这些技术是劳动密集型，耗时且昂贵的。简而言之，当前的DOS制造技术是非最佳的，不适合商业制造；需要一种新的，更灵活的制造技术。在这个STFC-CLASP项目中，我们将使用基于超快激光的技术开发新的DOS制造工艺。这些过程使用聚焦的超短激光脉冲，每个脉冲只有几百个飞秒的长度，以局部和精确地修改三维中底物材料的结构。激光诱导的修饰以多种方式表现出来，其中包括对修饰材料的化学蚀刻速率和/或折射率的更改。使用这些表现形式，可以将光学组件（例如衍射光栅）直接写入底物材料，并通过使用辐照后的化学蚀刻步骤，我们可以雕刻精度的微观镜头。 “超快激光铭文”使微观组件（例如镜头，镜子和光波指导）可以使用单个制造过程将其合并到单个基板上，这一事实使其成为商业生产精确DOS技术的理想途径。

项目成果

A Miniature Fibre-optic Raman Probe Fabricated by Ultrafast Laser Assisted Etching

超快激光辅助蚀刻制造的微型光纤拉曼探针

• DOI: 10.20944/preprints202001.0351.v1
• 发表时间: 2020
• 作者: Ross C