KEYWORDS: Scattering, Tissues, Monte Carlo methods, Polarization, Laparoscopy, RGB color model, Light scattering, In vivo imaging, Visualization, Solid state lighting
Peritoneal metastases are characterized by significant disruptions in the extracellular matrix. Hence, the scattering cross sections of malignant and benign lesions and surrounding background tissues are distinct. In this work, Monte Carlo based regression was used to develop an empirical relation to extract the scattering power of tissue based on co- and cross-polarized RGB reflectance images of tissue. The empirical relation improved the sensitivity of lesion detection, and discrimination accuracy of malignant and benign lesions. The proposed empirical equation is both accurate and simple, paving the way for real-time diagnostic applications.
KEYWORDS: Laparoscopy, Yield improvement, Polarization, Collagen, Visualization, Cancer, In vivo imaging, Scattering, Monte Carlo methods, Light scattering
While white light laparoscopy (WLL) has been established as a method that yields improved detection of peritoneal metastatic lesions over radiographic imaging, its sensitivity and specificity remain sub-optimal, leading to thousands of cancer patients that are over- or under- treated every year. We present studies that establish the sensitivity of polarization enhanced (PEL) laparoscopy to changes in the cross-section and alignment of scattering centers using phantoms and report on our initial in vivo human feasibility trial. The design of our PEL probe is simple and highly compatible with current laparoscopes, the standard of patient care and the established procedure flow for WLL. It comprises of a sheath inserted on the WLL laparoscope to provide linearly polarized illumination and a modified detection optical path that allows for recording of co- and cross-polarized images relative to the incident illumination. The sum of these images is equivalent to WLL, while their difference corresponds to PEL. Using PDMS phantoms with features that contain either TiO2 and ZnO2 particles, we demonstrate the enhanced sensitivity of PEL to scattering cross-section differences. Measurements performed with collagen gels that are being stretched reveal improved sensitivity of PEL (over WLL) to collagen fiber alignment. Our initial feasibility study results support the improved diagnostic potential of PEL. In fact, a Monte Carlo-based analysis approach that utilizes the color content of the PEL images indicates that PEL yields improved contrast for detection and differentiation of benign and malignant metastatic lesions. These studies provide strong motivation for further development of PEL imaging as an approach that may improve significantly the detection of peritoneal metastatic lesions.
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.