New technologies for optical coherence microscopy

Abstract

According to the American Cancer Society, gastrointestinal (GI) cancers are among the most common forms of malignancies suffered today, affecting -200,000 people and causing -80,000 deaths in the United States every year. The prognosis depends heavily on the detection of early-stage lesions. The process of endoscopic surveillance, excisional biopsy, and histologic examination is the current gold standard for screening and diagnosis of many GI cancers. This process, however, is invasive, time-consuming, and can suffer from unacceptable false negative rates. Optical imaging technology that provides real-time, high-resolution imaging of human tissue in vivo with resolution at or near that of histopathology may significantly improve clinicians' capabilities to identify malignancies at curable stages. The ability to assess histologic hallmarks of GI cancer at the tissue architectural and cellular levels without excisional biopsy would be a major advance in GI cancer management. Development of techniques to reliably image cellular and subcellular structure through endoscopic devices is one of the most outstanding challenges in biomedical imaging today and holds tremendous promise for surgical applications and for early diagnostic screening and staging of epithelial malignancies. Optical coherence microscopy (OCM) is an in vivo cellular imaging technique that combines OCT with confocal microscopy. Due to the unique feature of using two distinct optical sectioning techniques, OCM can provide superior imaging depth in highly scattered tissues and can overcome important imaging probe design limitations that hinder confocal microscopy. Two novel designs for OCM systems are proposed and developed for high resolution cellular imaging. The first uses Fourier domain optical coherence detection, and the second implements line-field illumination and detection. Differences in performance from the standard time-domain optical coherence microscopy systems will be studied.