Roblyer, DarrenEspinoza, Ethan Gabriel2024-01-192024-01-192024https://hdl.handle.net/2144/47948Colorectal cancer (CRC) currently ranks as the second leading cause of cancer-related death in the United States, according to 2020 statistics. Common procedures for diagnosis of CRC includes stool-based tests and white light colonoscopy surveillance. The colonoscopy procedure has the advantage of identifying patients at higher risk for developing metachronous lesions based on pathologic review of polypectomy specimens. Colorectal cancers are commonly identified by adenomas and polyps, which serve as the basis for polypectomy surveillance guidelines. However, approximately 17–24% of polyps are overlooked during colonoscopies using white light illumination. These missed lesions are attributed to tissue characteristics such as size and sessile, or flat, morphology. White light endoscopy only provides surface morphology of the rectal wall and does not resolve abnormal architecture and subsurface microvasculature. Broadband imaging (BBI) provides a potential way to increase the detection of polyps when imaging. BBI relies on the properties of hemoglobin as a major tissue chromophore. The range of wavelengths that can be chosen in BBI allows for greater penetration since longer wavelengths penetrate deeper into the tissue. When coupled to endoscopy, use of different wavelengths has been shown to reveal subepithelial microvascular architecture and microsurface structure within the GI mucosa. Thus, BBI can reveal tissue features that are not seen in white light endoscopy; this can include architectural features such as blood vessels from different depths. LEDs are a good source of broadband light sources due to their thermal management, long life span, and high power. This thesis aims to design and implement a low cost, portable, and efficient light source with fiber that can be used as a new imaging modality for colonoscopy. A cost-effective illumination device has been developed and validated for efficient coupling of light source to fiber. A custom fiber bundle has been developed to allow for maximum collection and emission of light. This device will be utilized to assess the validity of using broadband light sources in the visible to near infrared spectrum to image subsurface tissue features.en-USBiomedical engineeringThesis/Dissertation2024-01-180009-0001-3371-7601