Raman Probe for Bronchial Premalignant Lesions

描述（由申请人提供）：本项目的目标是通过检查由光纤拉曼探针确定的被观察组织的分子成分的附加信息，提高自身荧光内窥镜的诊断灵敏度，特别是特异性。该组合仪器将首先使用自身荧光成像来快速识别可能发育不良或癌变的组织区域。在标准的支气管镜检查程序中，将用镊子通过内窥镜狭窄的活检通道从该区域取一小块组织样本。在这个程序中，一个光纤拉曼探针将首先通过这个活组织检查通道，并轻轻按压可疑组织区域。1秒的窄带830nm光脉冲将通过探针远端的中心纤维和透镜组件直接照射到组织上。探针尖端的长通滤波器将阻挡830nm激发波长的后向散射，但将波长较长的组织荧光和拉曼位移光传递到收集纤维环中。这些收集纤维将把散射光带回光谱仪，光谱仪将其分散成特征拉曼“指纹”光谱。该光谱包含许多单独的峰，与组织中特定分子的浓度相对应。然后从组织部位进行标准活检，并送到病理实验室检查异常增生或癌症的证据。该程序将对测量的光谱进行编目，并将其与病理结果相关联。一旦光谱目录包含正常、发育不良和癌变组织指纹样本，就有可能开始实时预测病理结果。然而，在预测结果可能是可靠的之前，还需要从发现的癌症的许多不同阶段收集大量的光谱。在支气管镜检查过程中使用自身荧光成像已被证明比单独通过白光观察可以提高癌症诊断的敏感性。这意味着很少有真正癌变或发育不良的组织区域被认为是正常的（癌症的假阴性判断）。另一方面，该方法通常将正常组织分类为癌组织（假阳性判断），这导致患者因不必要的活组织检查而面临额外的风险，在手术过程中浪费时间和额外的费用。来自拉曼探针的额外信息有望识别出许多假阳性位点为真正正常的，从而增加组织表征的特异性。一旦该方法被证明是有效的，它将减少患者的风险，减少手术所需的时间，并减少不必要的活组织检查的成本。

DESCRIPTION (provided by applicant): The goal of this program is to improve the diagnostic sensitivity and especially the specificity of autofluorescence endoscopes by examining additional information on the molecular constituents of the tissue being observed as determined by a fiberoptic Raman probe. The combined instrument will first use autofluorescence imaging to quickly identify areas of tissue which are likely to be dysplastic or cancerous. In a standard bronchoscopy procedure a small sample of tissue from this area would be taken with forceps passed through the narrow biopsy channel of the endoscope. In this program, a fiberoptic Raman probe will first be passed through this biopsy channel and pressed lightly against the suspect area of tissue. A 1-second pulse of narrowband, 830 nm light will be directed onto the tissue through a central fiber and lens assembly at the distal tip of the probe. A long-pass filter in the tip of the probe will block the backscattered 830 nm excitation wavelength but pass the longer wavelength tissue fluorescence and Raman-shifted light into a ring of collection fibers. These collection fibers will carry the scattered light back to a spectrometer which will disperse it into a characteristic Raman "fingerprint" spectrum. This spectrum contains many individual peaks corresponding to the concentration of specific molecules in the tissue. The standard biopsy will then be taken from the tissue site and sent to a pathology lab to be examined for evidence of dysplasia or cancer. This program will catalog the measured spectra and correlate them with the results of pathology. Once the catalog of spectra contains samples of normal, dysplastic and cancerous tissue fingerprints it will be possible to begin to predict, in real-time, what the results of pathology will be. A large number of spectra will need to be collected, however, from many different stages of discovered cancers before the predicted results are likely to be reliable. The use of autofluorescence imaging during bronchoscopy procedures has been shown to improve the sensitivity of cancer diagnosis over that which can be achieved by white light observation alone. This means there are few instances where a truly cancerous or dysplastic area of tissue is seen to be normal (a false negative determination of cancer). On the other hand, the method often classifies normal tissue as cancerous (a false positive determination) which leads to an additional risk to the patient from unnecessary biopsies, wasted time during the procedure and additional costs. The additional information from the Raman probe is expected to be able to identify many of these false positive sites as truly normal, increasing the specificity of the tissue characterization. Once the method is proven to be effective it will reduce patient risk, reduce the time required for procedures and reduce the cost of unnecessary biopsies.