Published online Jul 14, 2014. doi: 10.3748/wjg.v20.i26.8449
Revised: February 14, 2014
Accepted: March 12, 2014
Published online: July 14, 2014
There have been major developments in endoscopic imaging techniques in recent years. Endoscopes with high definition and magnification can provide high quality images that allow for the histological estimation of lesions in vivo and in situ when combined with ancillary enhancement techniques such as chromoendoscopy (CE) and virtual CE (narrow band imaging fujinon intelligent chromoendoscopy, or i-Scan). Despite the enormous potential for these advanced techniques, their value and feasibility in the clinic are still doubted, particularly in cases of colonic polyps that are slated for removal, where in vivo characterization may be deemed unnecessary. However, there are several advantages offered by such advanced endoscopic imaging. CE with or without magnification demonstrates highly accurate histology and invasion depth prediction, and virtual CE is a feasible and less cumbersome alternative to CE in terms of histological estimation, though not sufficiently accurate for depth invasion prediction. Furthermore, the supplementary information provided by advanced imaging systems can assist the endoscopist in the selection of a strategic approach, such as in deciding whether a colonic lesion should be resected, left in situ, or requires more intensive surgical treatment. Lastly, advanced high-resolution imaging techniques may be more cost effective, such that histopathology of low-risk lesions following resection can be eliminated. The results of these evaluations and comparisons with traditional CE are presented and discussed. Taken together, the benefits provided by these advanced capabilities justify their development, and advocates their use for the treatment and management of colonic polyps.
Core tip: Endoscopic characterization of colonic polyps by “virtual histology” is a currently accessible tool for identification of lesion type, thus enabling endoscopists to determine optimal treatment strategies. Chromoendoscopy (CE) has shown high accuracy for differentiating polyp histologies (neoplastic vs non-neoplastic) and for estimating the depth of invasion. Furthermore, digital systems such as narrow band imaging are a viable alternative to CE regarding lesion characterization, ease of use, reversibility, and cleanliness.