This Small Business Innovation Research (SBIR) Phase I project seeks to develop a new clinical instrument capable of using a novel optical technology to scan large areas of epithelial tissue for the detection and localization of precancers. The optical technology, angle-resolved Low Coherence Interferometry (a/LCI) has shown excellent sensitivity and specificity for detecting precancerous lesions during in vivo testing with Barrett's Esophagus patients but has been confined to single point measurements. To have the greatest clinical impact, the modality must be extended to scan wide tissue areas. This project will offer significant advantages due to the unique imaging geometry of the a/LCI approach. While the use of scanning schemes for traditional imaging methods have been investigated, the a/LCI approach relies on measuring the angular distribution of scattered light. Thus, wide area scanning implementations of a/LCI will require a novel optical design to address issues not commonly of interest in imaging. The research plan calls for building a scanning system capable of interrogating at least 5 locations separated by 1 millimeter within one second without repositioning the probe to demonstrate proof-of-concept for the approach. The broader impact/commercial potential of this project centers on the field of early cancer detection and diagnosis. Traditional evaluation of the health of epithelial tissues requires systematic tissue removal with subsequent examination by a pathologist. Biopsy sampling error is a significant problem with early cancerous tissues often eluding detection, as there may not be evidence of disease at the tissue surface. The proposed a/LCI system has the potential to greatly improve endoscopic screening and surveillance of epithelial tissues for precancerous lesions. Interviews with practicing clinicians and feedback from initial field trial sites of the a/LCI technology point to widespread market adoption of this instrument but also identify the preference for automated tissue scanning over the current point imaging modality. The high throughput of the proposed wide area scanning system will provide comprehensive assessments of tissue health in a way that is not possible using histopathological evaluation of excised biopsies. The low cost of the a/LCI system and its ease-of-use will enable widespread applications, a factor which is increasingly valued in the current, fiscally conscious health care environment