Rediscovering histology: what is new in endoscopy for inflammatory bowel disease?

Abstract

The potential of endoscopic evaluation in the management of inflammatory bowel diseases (IBD) has undoubtedly grown over the last few years. When dealing with IBD patients, histological remission (HR) is now considered a desirable target along with symptomatic and endoscopic remission, due to its association with better long-term outcomes. Consequently, the ability of endoscopic techniques to reflect microscopic findings in vivo without having to collect biopsies has become of upmost importance. In this context, a more accurate evaluation of inflammatory disease activity and the detection of dysplasia represent two mainstay targets for IBD endoscopists. New diagnostic technologies have been developed, such as dye-less chromoendoscopy, endomicroscopy, and molecular imaging, but their real incorporation in daily practice is not yet well defined. Although dye-chromoendoscopy is still recommended as the gold standard approach in dysplasia surveillance, recent research questioned the superiority of this technique over new advanced dye-less modalities [narrow band imaging (NBI), Fuji intelligent color enhancement (FICE), i-scan, blue light imaging (BLI) and linked color imaging (LCI)]. The endoscopic armamentarium might also be enriched by new video capsule endoscopy for monitoring disease activity, and high expectations are placed on the application of artificial intelligence (AI) systems to reduce operator-subjectivity and inter-observer variability. The goal of this review is to provide an updated insight on contemporary knowledge regarding new endoscopic techniques and devices, with special focus on their role in the assessment of disease activity and colorectal cancer surveillance.

Keywords: artificial intelligence; capsule enteroscopy; confocal laser endomicroscopy; dye-chromoendoscopy; endocytoscopy; inflammatory bowel diseases; molecular imaging; virtual chromoendoscopy.

Figure 1.

Rectum flat elevated lesion (IIa + IIb according to the Paris classification), pit Patter IIIL–IV according to the Kudo classification. (a) WLE. (b) LCI. (c) BLI. Histologic examination: high grade dysplasia. Blue light imaging; LCE, linked color imaging; WLE, white-light endoscopy.

Figure 2.

Descending colon flat lesion (IIb according to the Paris classification), pit Patter IIIL according to the Kudo classification at the same specific points. (a) WLE. (b) DCE. (c) Detail with DCE. Histologic examination: biopsies on the white area compatible with chronic inflammation; biopsies on the lesion compatible with low grade dysplasia. DEC, dye-chromoendoscopy; WLE, white-light endoscopy.

Figure 3.

Flat elevated lesion in the ascending colon (IIa according to the Paris classification), pit pattern serrated (IIO according to the Kudo classification). (a) WLE. (b) LCI. (c) BLI. Histologic examination: serrated lesion without dysplasia. Blue light imaging; LCE, linked color imaging; WLE, white-light endoscopy.