For a favorable treatment result, early diagnosis of pathological cancerous micro-areas with their subsequent removal is highly important and can be achieved by the development of new modeling techniques and conducting relevant experiments. Various models of the bladder can be developed and applied to provide a platform for studying, processing and improving the signals received from various video systems. Here, in order to study visualization properties at fluorescence endoscopy, 3D optical phantoms of urinary bladder have been developed. The phantoms simulated optical properties of the bladder wall, including localized areas that represent tumor tissues and contained PpIX photosensitizer at various concentrations for fluorescence "diagnostics". To perform bimodal fluorescence imaging, a two-channel video fluorescence system was used. First, intraoperative images of the bladder wall were obtained in a patient with bladder cancer. A video system was used to reveal and image pathological areas with increased fluorescence intensity. Fluorescence indices in tumor tissue were recorded and corresponded to different concentrations of PpIX photosensitizer. Then, a bimodal fluorescence imaging was performed on 3D phantoms. The obtained images and fluorescence intensity measurements showed the ability of the video fluorescence system to register bladder wall structures and accumulated in them photosensitizers in concentrations from 0.25 to 20 mg/kg. The developed models can serve as a useful instrument for test measurements for constructing multimodal mosaic panoramic images of the bladder surface. This will help to advance in solving problems of endoscopic image processing using bimodal imaging, which uses diagnostic (fluorescence) and color channels.
Brain glial tumors have peculiar features of the perifocal region extension, characterized by its indistinct area, which
complicates determination of the borders for tissue resection. In the present study filter-reduced back-scattered laser light
signals, compared to the data from mathematical modeling, were used for description of the brain white matter. The
simulations of the scattered light distributions were performed in a Monte Carlo program using scattering and absorption
parameters of the different grades of the brain glial tumors. The parameters were obtained by the Mie calculations for
three main types of scatterers: myelinated axon fibers, cell nuclei and mitochondria. It was revealed that diffuse-reflected
light, measured at the perifocal areas of the glial brain tumors, shows a significant difference relative to the signal,
measured at the normal tissue, which signifies the possibility to provide diagnostically useful information on the tissue
state, and to determine the borders of the tumor, thus to reduce the recurrence appearance. Differences in the values of
ratios of diffuse reflectance from active growth parts of tumors and normal white matter can be useful for determination
of the degree of tumor progress during the spectroscopic analysis.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.