Present and future perspectives of virtual chromoendoscopy with i-scan and optical enhancement technology

Despite being the current gold standard, white-light endoscopy may miss a significant proportion of lesions within the colorectum, thus leading to a misinterpretation of various disease findings. Traditionally, dye-based chromoendoscopy is used to improve both detection and characterization of lesions during luminal gastrointestinal (GI) endoscopy. Recently introduced dye-less chromoendoscopy (DLC) techniques have overcome many of the limitations of dye-based chromoendoscopy, thereby potentially improving lesion recognition and characterization. In detail, DLC techniques allow for better detection of esophageal lesions, gastric cancer and colorectal pathologies including colorectal polyps and inflammatory bowel diseases. Moreover, DLC techniques enable a more precise characterization of lesions throughout the whole luminal GI tract, thereby potentially enabling more accurate endoscopic therapies. In the present review we focus on the newly introduced dye-less chromoendoscopy technique i-scan and give an additional outlook on the recent development of optical enhancement technology.