Diffuse reflectance spectroscopy has been previously explored as a promising method for providing real-time visual
maps of tissue composition to help surgeons determine breast lumpectomy margins and to ensure the complete removal
of a tumor during surgery. We present the simple design, validation, and implementation of a compact and cost-effective
spectral imaging system for the application of tumor margin assessment. Our new system consists of a broadband source
with bandpass filters for illumination and a fabricated custom 16-pixel photodiode imaging array for the detection of
diffuse reflectance. The system prototype was characterized in tissue-mimicking phantoms and has an SNR of greater
than 40 dB in phantoms, animals, and human tissue. We show proof-of-concept for performing fast, wide-field spectral
imaging with a simple, inexpensive design. The strategy also allows for the scaling to higher pixel number and density in
future iterations of the system.
There is clinical utility for a wide-field, spectroscopic imaging device for quantitative tissue absorption and scattering in
a number of applications. We present the design of a compact, cost-effective spectroscopic imaging system, which
consists of a broadband source with bandpass filters and a light guide for illumination and an inexpensive array of silicon
photodiodes for detection. A single-pixel version of the system was tested in liquid phantoms simulating a wide range of
human breast tissue and optical properties can be extracted with absorption and reduced scattering errors of 12.6% and
4.7%, respectively. We show proof-of-concept for performing fast, wide-field spectroscopic imaging with a simple
design. The design also allows for scaling and expansion into higher pixel number and density in future iterations of
custom device design, which includes in-house photodiode array fabrication processes and integration of on-board
current amplifier circuits.
A hybrid optical device that uses a multimode fiber coupled to a tunable light source for illumination and a 2.4-mm photodiode for detection in contact with the tissue surface is developed as a first step toward our goal of developing a cost-effective, miniature spectral imaging device to map tissue optical properties in vivo. This device coupled with an inverse Monte Carlo model of reflectance is demonstrated to accurately quantify tissue absorption and scattering in tissue-like turbid synthetic phantoms with a wide range of optical properties. The overall errors for quantifying the absorption and scattering coefficients are 6.0±5.6 and 6.1±4.7%, respectively. Compared with fiber-based detection, having the detector right at the tissue surface can significantly improve light collection efficiency, thus reducing the requirement for sophisticated detectors with high sensitivity, and this design can be easily expanded into a quantitative spectral imaging system for mapping tissue optical properties in vivo.