Fiberoptic Technology Maps Microvascular Blood During Colonoscopy

Fiberoptic technology can effectively measure blood levels in the colonic lining (mucosa) in humans, thus having potential applications for analyzing risk of colon cancer.

Two hundred and twenty-two patients undergoing colonoscopy screening were recruited for a study in 2006 and 2007. During the colonoscopy, a fiberoptic probe was used to measure oxygenated (OHb) and deoxygenated (DHb) hemoglobin (Hb), specifically in the colonic lining where small blood vessels circulate

The study found that the total Hb concentration was elevated 75.3% above control levels (comparable region from patients with no adenomas) at the adenoma site and persisted in the uninvolved mucosa (microscopically normal) area. Moreover, tissue sites located within 10- and 30-cm away from an adenoma also manifested a highly statistically significant increase in total Hb, OHb, and DHb concentration.

The results provide the first indication that the early increase in blood supply (EIBS) is detectable in humans and that a high blood level mirrors proximity to neoplasia (process of tumor formation). The findings also suggest that this technology could be a valuable screening tool for enhancing polyp detection and could lead to improvements in colon cancer prevention.

The light probe was developed by Dr. Vadim Backman, professor of biomedical engineering at Northwestern University's McCormick School of Engineering and Applied Science (Evanston, IL, USA). It utilizes a light-scattering technology that can detect subtle abnormal changes in cells lining the colon long before those changes can be seen under a microscope, and even before polyps form.

The study appeared in the October 2008 issue of the journal Gastroenterology, the official journal of the American Gastroenterological Association (AGA) Institute.

Related Links:
Northwestern University's McCormick School of Engineering and Applied Science