Structured light radial-view endoscope PROBE for IMAGING of colorectal tissue.

White-light endoscopy (WLE) is the current gold standard for endoscopic colorectal cancer screening. However, it lacks the ability to image subsurface colorectal tissue and provide functional assessments necessary for early-stage cancer identification and post-treatment evaluation. Spatial frequency domain imaging (SFDI) provides subsurface quantitative absorption and scattering properties, which can assist in distinguishing between different tissue types. In this paper, we present a new, to the best of our knowledge, compact, radial-view, dual-wavelength (740 nm and 850 nm) SFDI system and its accompanying reconstruction algorithm. The proposed system achieves real-time full circumferential imaging of the intestinal lumen and provides functional parameter estimation from a single snapshot. The performance of this endoscopic probe is evaluated using biomimetic microvascular phantoms, and its potential for biological tissue imaging is demonstrated through imaging of ex vivo human colorectal tissue.