Optical molecular imaging for detection of Barrett's-associated neoplasia

Recent advancements in the endoscopic imaging of Barrett's esophagus can be used to probe a wide range of optical properties that are altered with neoplastic progression. This review summarizes relevant changes in optical properties as well as imaging approaches that measures those changes. Wide-field imaging approaches include narrow-band imaging that measures changes in light scattering and absorption, and autofluorescence imaging that measure changes in endogenous fluorophores. High-resolution imaging approaches include optical coherence tomography, endocytoscopy, confocal microendoscopy, and high-resolution microendoscopy. These technologies, some coupled with an appropriate contrast agent, can measure differences in glandular morphology, nuclear morphology, or vascular alterations associated with neoplasia. Advances in targeted contrast agents are further discussed. Studies that have explored these technologies are highlighted; as are the advantages and limitations of each.