Role of Advanced Endoscopic Imaging Techniques in the Management of Inflammatory Bowel Disease

Moxifloxacin promotes two-photon microscopic imaging for discriminating different stages of DSS-induced colitis on mice

BACKGROUND

Accurate diagnosis of patients with ulcerative colitis (UC) can reduce their risk of developing colorectal cancer. This study intended to explore whether moxifloxacin, an agent with fluorescence potential, could promote two-photon microscopy (TPM) diagnosis for mice with dextran sodium sulfate (DSS)-induced colitis, which could imitate human UC.

METHODS

32 Balb/c mice were randomly divided into 4 groups: control, acute colitis, remission colitis and chronic colitis. Fluorescence parameters, imaging performance, and tissue features of different mouse models were compared under moxifloxacin-assisted TPM and label-free TPM.

RESULTS

Excitation wavelength of 720 nm and moxifloxacin labeling time of 2 min was optimal for moxifloxacin-assisted TPM. With moxifloxacin labeling for colonic tissues, excitation power was decreased to 1/10 of that without labeling while fluorescence intensity was increased to 10-fold of that without labeling. Photobleaching was negligible after moxifloxacin labeling and moxifloxacin fluorescence kept stable within 2 h. Compared with the control group, moxifloxacin fluorescence was reduced in the three colitis groups (P < 0.05). Meanwhile, the proportion of enhanced moxifloxacin fluorescence regions was (22.4 ± 1.6)%, (7.7 ± 1.0)%, (13.5 ± 1.7)% and (5.0 ± 1.3)% in the control, acute, remission and chronic groups respectively, with significant reduction in the three colitis groups (P < 0.05). Besides, variant tissue features of experimental colitis models were presented under moxifloxacin-assisted TPM, such as crypt opening, glandular structure, adjacent glandular space and moxifloxacin distribution.

CONCLUSIONS

With unique biological interaction between moxifloxacin and colonic mucosa, moxifloxacin-assisted TPM imaging is feasible and effective for accurate diagnosis of different stages of experimental colitis.

Artificial intelligence-assisted endoscopy changes the definition of mucosal healing in ulcerative colitis

The relevance of endoscopic monitoring of ulcerative colitis (UC) has been translated into the new concept of "mucosal healing (MH)" as the therapeutic goal to achieve because a large amount of scientific data have revealed the favorable prognostic value of a healed mucosa in determining the clinical outcome of UC. Recent interest in MH has skewed toward not only endoscopic remission but also histological improvement (so called histological MH). However, we should recognize that there have been no prospectively validated endoscopic scoring systems of UC activity in previous clinical trials. Artificial intelligence (AI)-assisted endoscopy has been developed for gastrointestinal cancer surveillance. Recently, several AI-assisted endoscopic systems have been developed for assessment of MH in UC. In the future, the development of a new endoscopic scoring system based on AI might standardize the definition of MH. Therefore, "The road to an exact definition of MH in the treatment of UC has begun only now".

Advanced neoplasia detection using chromoendoscopy and white light colonoscopy for surveillance in patients with inflammatory bowel disease

Background/Aims

Chromoendoscopy (CE) has been shown to be superior to white light endoscopy (WLE) for neoplasia detection in inflammatory bowel disease (IBD). We aimed to compare the yield of CE and WLE for the detection of overall neoplasia and advanced neoplasia in IBD.

Methods

Patients who underwent surveillance colonoscopy from 1999 to 2017 were identified from our IBD database. CE procedures were compared with their respective WLE controls in a paired comparison, and frequency of all neoplasia, advanced neoplasia, and serrated neoplasia was assessed for both targeted and random biopsies.

Results

A total of 290 procedures performed in 98 individuals were identified with a median follow-up 4 years (median 3 colonoscopies/patient). CE and WLE were performed in 159 and 131 episodes, respectively. CE detected neoplasia in 40.9% of colonoscopies versus 23.7% with WLE (P= 0.002). In addition, CE detected more advanced neoplasia (18.2% vs. 6.1%, P= 0.002) and serrated lesions (14.5% vs. 6.1%, P= 0.022). Significantly fewer samples were obtained per procedure with CE (14.9 ± 9.7 vs. 20.9 ± 11.1, P< 0.001). Cancer was diagnosed in 2 cases.

Conclusions

CE has a higher detection rate than WLE for advanced neoplasia and serrated lesions in patients with IBD under surveillance. Further prospective studies evaluating the impact of CE on decreasing the risk of interval cancer and colectomy in IBD patients are warranted.

Meta-analysis of Virtual-based Chromoendoscopy Compared With Dye-spraying Chromoendoscopy Standard and High-definition White Light Endoscopy in Patients With Inflammatory Bowel Disease at Increased Risk of Colon Cancer

BACKGROUND

Patients with inflammatory bowel disease (IBD) have an increased risk of colorectal cancer. We sought to assess the comparative efficacy of virtual chromoendoscopy (VCE) vs high definition white light endoscopy (HDWLE) or dye-spraying chromoendoscopy (DCE) through a meta-analysis and rating the quality of evidence.

METHODS

A systematic review of the literature was performed through February 15, 2019. Primary outcomes were number of patients in whom dysplasia was identified and number of dysplastic lesions identified in these patients. We included only randomized control trials (RCTs) and performed meta-analysis using RevMan5.3.

RESULTS

Of the 3205 studies identified, 11 RCTs were included, with a total of 1328 patients. Per patient analysis, VCE was not statistically different compared with DCE (risk ratio [RR] 0.77; 95% CI, 0.55-1.08) or HDWLE (RR 0.72; 95% CI, 0.45-1.15). However, per dysplasia analysis, VCE was not statistically different compared with DCE (RR 0.72; 95% CI, 0.47-1.11) and inferior compared with HDWLE (RR 0.62; 95% CI, 0.44-0.88). The quality of evidence was moderate in the HDWLE and low to moderate in the DCE studies.

CONCLUSION

Based on this meta-analysis, VCE was as good as HDWLE and DCE in identifying dysplasia per patient analysis. However, per dysplasia analysis, VCE was inferior compared with HDWLE and no different from DCE. Further studies need to examine the efficacy of each individual VCE technique.

Surgical Management of Dysplasia and Cancer in Inflammatory Bowel Disease

Patients with inflammatory bowel disease are at an increased risk of cancer secondary to long-standing intestinal inflammation. Surgical options must take into account the significant risk of synchronous disease at other colonic sites. Ileal pouch anal anastomosis is a viable option for patients with ulcerative colitis, but this should be restricted to early cancers that are unlikely to require preoperative or postoperative radiation treatment.