Refractive Index modulated spectral near infrared diffuse optical breast imaging

Despite decades of efforts, near infrared optical imaging methods for breast cancer detection and diagnosis have not been approved for clinical translation. Several practical and inherent physical limitations lead to lack of robust performance for existing optical breast imaging systems in comparison to X-ray mammography and tomosynthesis that are FDA approved. A major hurdle is the significant light scattering in dense tissue. Another issue is the low optical resolution along with the ill conditioned nature of inversion with the existing NIR imaging methods. In this work, we explore the use of scatter reduction using refractive index matching dyes to enhance the performance of continuous wave near infrared optical imaging. This refractive index modulation is combined with novel illumination, spectroscopic detection schemes and mechanisms such as dynamic breast compression to induce hemodynamic signal changes to significantly increase sensitivity. We explore these effects of refractive index modulation and dynamic variations in both reflectance and transmittance measurements to potentially yield translatable, low cost and high sensitive breast imaging system.