Abstract
The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools.
Highlights
The refractive index is an optical constant that plays a significant role in the description of light-matter interactions
Via Fresnel analysis, a complex refractive index was calculated for each experimental run
Taking into account the mm-diameter of the laser beams, this result is directly interpreted as the microscopically-averaged effective index, thereafter referred to as “refractive index”
Summary
The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. The refractive index is a readily determined real number that quantifies the apparent reduction of the speed of light inside the medium, relative to the speed of light in vacuum. Tissues, are both absorbing and highly inhomogeneous, comprising internal arbitrarily-shaped structures in the macroscopic (≥mm) and microscopic (say, 50 nm to 50 μm) scale, the latter giving rise to photon multiple scattering effects[3,4,5]. To analyze the micro-optical properties of tissues, the concept of the “effective” refractive index has been introduced within the frame of an effective medium theory[6]. On the grounds of their operating principle, www.nature.com/scientificreports/
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
