Estimation of tissue optical properties between different grades and stages of urothelial carcinoma using diffuse reflectance spectroscopy

The standard clinical practice for detection of bladder tumours is standard white light cystoscopy. Major concerns related to cystoscopy include its invasive, causes discomfort to the patient and also it misses flat tumors (carcinoma in situ). Recently, considerable progress has been made in the development of optical spectroscopy and imaging based on fluorescence, reflectance and Raman for disease diagnosis. The basic objective behind optical technologies to is skip the time consuming tissue pathology, to provide real time results and moreover to reduce the emotional strain on the patients waiting for the results. In this context, we propose to implement diffuse reflectance spectroscopy for staging and grading urothelial carcinoma by estimating the tissue optical properties such as absorption and reduced scattering co-efficients. Tissue optical properties emulates the underlying physiological and morphological properties of the tissue. In the visible region of spectrum light absorption is dominated by hemoglobin. While light scattering is primarily due to the changes in nuclear size and density as well as from the collagen fibres. Tumour tissues exhibit considerable changes in these properties which could be quantified using reflectance spectroscopic measurements. Our study indicates a changes in the reflectance spectral profile between normal and different grades of urothelial carcinoma. Also, at wavelengths greater than 640 nm (where scattering is dominant) we found an increased intensity when compared to the normal tissues.