Polarization Sensitive OCT for Detection of Melanoma

描述（由申请人提供）：光学相干断层扫描（OCT）是一项最近发展起来的成像技术，它允许对生物组织中的微米级结构进行原位、实时、非侵入性、非接触、横断面成像，因此似乎是研究皮肤癌的一种合适的方式。偏振敏感光学相干层析成像技术（PS-OCT）的发展允许获取由反射光携带的组织偏振特性的附加信息。恶性黑色素瘤是皮肤癌的一种，其发病率增长速度是所有癌症中最快的。然而，肉眼检测黑色素瘤，即使是黑色素瘤专家，也只有60-80%的灵敏度。因此，迫切需要新的方法来分析体内可疑的皮肤病变。在本研究中，我们将构建PS-OCT系统来区分正常、良性和恶性组织。PS-OCT系统将控制入射到样品上的光的偏振状态。通过测量在特定偏振状态下返回的光的反射率，我们将获得穆勒矩阵，该矩阵提供了样品偏振特性的完整表示。在该项目的第一年，我们将使用快速扫描光延迟线完成高速PS-OCT系统的构建和改进。第二年，将利用转基因小鼠模型结合PS-OCT研究黑色素瘤多期癌变及良、恶性病变分化。这种转基因小鼠模型使用酪氨酸酶启动子来靶向突变的人类T24 Ha-ras癌基因的表达，这是鲍威尔博士之前开发的，他将在第二年担任顾问。开发一种能够判断色素病变良恶性的系统的总体目标将通过以下具体目标来实现：(1)开发PS-OCT仪器，(2)比较PS-OCT和组织学来区分良恶性病变。这一试点项目的成功完成将进一步发展一种实用和廉价的设备，可用于区分皮肤的良性和恶性病变。因此，这项研究将有可能改善患者护理，减少黑色素瘤的人力和经济成本。

DESCRIPTION (provided by applicant): Optical Coherence Tomography (OCT) is a recently developed imaging technology, which permits in-situ, real-time, non-invasive, non-contact, cross-sectional imaging of micron-scale structures in biological tissues and as such seems to be a suitable modality for the study of skin cancer. The development of polarization sensitive optical coherence tomography (PS-OCT) permits the acquisition additional information on the polarization properties of tissue carried by the reflected light. Malignant melanoma, a form of skin cancer, is increasing in incidence at the most rapid rate of all cancers. Yet detection of melanoma visually, even by experts in melanoma, has only 60-80% sensitivity. Thus, new methods of analyzing suspicious skin lesions in vivo are urgently needed. In this proposed study, we will construct a PS-OCT system to distinguish between normal, benign and malignant tissues. The PS-OCT system will control the polarization state of the light incident upon the sample. By measuring the reflectivity of light returning in particular polarization states we will obtain the Mueller matrix that provides complete representation of the polarization properties of the sample. During the first year of this project, we will complete construction and refinement of a high speed PS-OCT system by using a rapid scan optical delay line. In the second year, a transgenic mouse model will be used in conjunction with PS-OCT to study multistage melanoma carcinogenesis and differentiation of benign and 1 malignant lesions. This transgenic mouse model uses tyrosinase promoter to target expression of the mutated human T24 Ha-ras oncogene, as previously developed by Dr. Powell who will serve as a consultant in the second year. The overall goals of developing a system capable of determining benign from malignant pigmented lesions will be achieved through the following specific aims: (1) develop PS-OCT instrumentation, (2) compare PS-OCT and histology to differentiate benign from malignant lesions. Successful completion of this pilot project will further the development of a practical and inexpensive device that can be used to differentiate benign from malignant lesions of the skin. Thus this research will have the potential to improve patient care and reduce the human and economical cost of melanoma.