The role of ultra‐high definition endoscopy (endomicroscopy and endocytoscopy) and real time histologic examination in inflammatory bowel disease: a scoping review

Objectives

Confocal laser endomicroscopy (CLE) and endocytoscopy (EC) are ultra‐high definition (HD) imaging modalities that enable real time histological assessment. Although existent for nearly two decades, their role in current clinical decision making in IBD management is not well defined.

Methods

We searched the PubMed using keywords ("confocal" OR “CLE" OR “endocytoscopy”) AND ("IBD" OR "Inflammatory bowel" OR "Crohn*" OR "Crohn's" OR "colitis ulcerosa" OR "ulcerative colitis”) between 2005 to March 2023. We identified 52 studies for detailed review.

Results

CLE was useful in real‐time assessment of histologic inflammation and dysplasia characterization in both ulcerative colitis (UC) and Crohn's disease (CD). Although, CLE was associated higher per‐biopsy yield for UC associated neoplasia (UCAN), the benefit was offset by higher procedure time, frequent equipment failure and conflicting results on incremental yield over chromoendoscopy. Assessment of barrier dysfunction by CLE did not correlate with disease/endoscopic activity but could predict major adverse outcomes. The implications of residual CLE abnormalities in endoscopic remission remain uncertain. Ex vivo binding of labelled biologics can help in predicting biologic response in UC.

EC can discriminate of mucosal inflammatory cells by morphology and allows assessment of histologic activity. EC combined with pit pattern was better than pit pattern alone for UCAN. Artificial intelligence assisted EC in UCAN needs further study.

Conclusion

Ultra HD imaging in IBD can be useful in assessment of UCAN, barrier dysfunction, predicting histologic remission and biologic response. Future controlled studies are warranted to define the role of these novel technologies in clinical decision making.