Reflectance Spectra And Detection Technique Of Nasopharyngeal Carcinoma Tissue

Nasopharyngeal carcinoma(NPC)incidence and mortality have been increasing in Southeast Asia and Southern China,according to a report by the World Health Organisation(WHO).Reflectance spectroscopy is a simple,low-cost,and noninvasive method.With a view to the current clinical demand,in this thesis,the reflectance spectroscopy was emlployed for human NPC tissue analysis in order to develop a rapid,objective,clinical detection method.The main research results as follows:1.Reflectance spectra(400-700 nm)were acquired from nasopharyngeal ex vivo tissues belonging to 18 noncancerous and 19 cancerous subjects,and the multivariate statistical analysis was employed to classify different types of tissue group,achieving a diagnostic sensitivity of 70.2%and a specificity of 73.6%.In addition,we found that average spectral intensity ratios of oxyhemoglobin(R540/R576)could be used as an indicator of the carcinogenesis associated transformation in the hemoglobin oxygenation.This tentative work demonstrated the potential of reflectance spectroscopy for NPC detection using ex vivo tissue and has significant experimental and clinical value for further in vivo NPC detection.2.An image guided endoscopy system based on reflectance spectroscopy was utilized to realize in vivo tissue diagnosis in the nasopharynx.A total of 26 tumor sites and 25 noncancerous sites were acquired from 51 patients who underwent pharyngorhinoscopy.The diagnostic algorithms based on the multivariate statistical analysis on reflectance spectra yielded a diagnostic sensitivity of 77.4%and specificity of 75.5%for NPC identification.Moreover,reflectance spectroscopy is capable of exploring significant differences between non-cancerous and cancerous tissues.Average spectral intensity ratios of oxyhemoglobin(R544/R576)were used as an indicator of the carcinogenesis associated transformation,indicating this result was consistent with the ex vivo work.This study demonstrates that reflectance spectroscopy has the potential for distinguishing in vivo NPC and providing a new method for in vivo NPC detection.3.An image guided endoscopy system coupled with a special designed fiber-optic Raman probe was utilized to realize simultaneous reflectance spectroscopy and Raman spectroscopy measurements in the nasopharynx.The fiber-optic Raman probe can be inserted into the biopsy channel of endoscopes and obtained Raman signals after reflectance spectra test.Raman spectroscopy can infer quantitative information from inherent chemical and molecular features.This work shows that the simultaneous reflectance spectroscopy and Raman spectroscopy technique has the potential for the noninvasive,real-time and in vivo diagnosis,which can be a clinically powerful tool for NPC diagnosis.