Standard Definition White Light Endoscopy Research Articles

Standard-definition White-light, High-definition White-light versus Narrow-band Imaging Endoscopy for Detecting Colorectal Adenomas: A Multicenter Randomized Controlled Trial.

This study aimed to compare the performance of standard-definition white-light endoscopy (SD-WL), high-definition white-light endoscopy (HD-WL), and high-definition narrow-band imaging (HD-NBI) in detecting colorectal lesions in the Chinese population. This was a multicenter, single-blind, randomized, controlled trial with a non-inferiority design. Patients undergoing endoscopy for physical examination, screening, and surveillance were enrolled from July 2017 to December 2020. The primary outcome measure was the adenoma detection rate (ADR), defined as the proportion of patients with at least one adenoma detected. The associated factors for detecting adenomas were assessed using univariate and multivariate logistic regression. Out of 653 eligible patients enrolled, data from 596 patients were analyzed. The ADRs were 34.5% in the SD-WL group, 33.5% in the HD-WL group, and 37.5% in the HD-NBI group (P=0.72). The advanced neoplasm detection rates (ANDRs) in the three arms were 17.1%, 15.5%, and 10.4% (P=0.17). No significant differences were found between the SD group and HD group regarding ADR or ANDR (ADR: 34.5% vs. 35.6%, P=0.79; ANDR: 17.1% vs. 13.0%, P=0.16, respectively). Similar results were observed between the HD-WL group and HD-NBI group (ADR: 33.5% vs. 37.7%, P=0.45; ANDR: 15.5% vs. 10.4%, P=0.18, respectively). In the univariate and multivariate logistic regression analyses, neither HD-WL nor HD-NBI led to a significant difference in overall adenoma detection compared to SD-WL (HD-WL: OR 0.91, P=0.69; HD-NBI: OR 1.15, P=0.80). HD-NBI and HD-WL are comparable to SD-WL for overall adenoma detection among Chinese outpatients. It can be concluded that HD-NBI or HD-WL is not superior to SD-WL, but more effective instruction may be needed to guide the selection of different endoscopic methods in the future. Our study's conclusions may aid in the efficient allocation and utilization of limited colonoscopy resources, especially advanced imaging technologies.

Systematic review with network meta-analysis: endoscopic techniques for dysplasia surveillance in inflammatory bowel disease.

International guidelines recommend dysplasia surveillance in IBD. To compare endoscopic techniques for dysplasia surveillance METHODS: We searched MEDLINE, Embase, CENTRAL for randomised trials through May 2019. We estimated odds ratios (ORs) for binary and mean differences (MDs) for continuous outcomes, using frequentist random-effects network meta-analysis. We assessed study risk of bias and appraised evidence certainty using GRADE. Eighteen trials (2638 participants) were included. Standard definition white-light endoscopy (OR 0.44, 95% CI 0.26-0.73; high certainty) and i-SCAN (OR 0.47, 95% CI 0.25-0.90; moderate certainty) had lower odds of detecting neoplasia than chromoendoscopy. Fujinon intelligent colour enhancement (FICE), standard definition white-light endoscopy and i-SCAN had lower odds for this outcome than full spectrum high definition white-light endoscopy (ORs 0.02 to 0.15; low certainty). Standard definition white-light endoscopy had lower odds of detecting nonpolypoid neoplasia than full spectrum high definition white-light endoscopy, narrow band imaging, chromoendoscopy and high definition white-light endoscopy (ORs 0.01-0.14; moderate certainty). Full spectrum high definition white-light endoscopy ranked as the best technique for both outcomes (moderate certainty). Standard definition white-light endoscopy had lower odds of detecting neoplasia by target biopsy (OR 0.27, 95% CI 0.08-0.91) and had shorter procedure time (MD -14.81minutes, 95% CI -25.03, -4.06) than chromoendoscopy (moderate certainty). Chromoendoscopy, high definition white-light endoscopy, narrow band imaging, autofluorescence, FICE and full spectrum high definition white-light endoscopy may be comparable for dysplasia surveillance. Standard definition white-light endoscopy and i-SCAN probably provide lower yields for neoplasia identification. Full spectrum high definition white-light endoscopy may represent the first-line approach.

Comparison of Endoscopic Dysplasia Detection Techniques in Patients With Ulcerative Colitis: A Systematic Review and Network Meta-analysis.

We assessed the comparative efficacy of different dysplasia detection techniques in patients with ulcerative colitis (UC) through a network meta-analysis and rated the quality of evidence using GRADE approach. Through a systematic literature review of multiple databases through June 30, 2017, we identified parallel-group randomized controlled trials (RCTs) in adults with long-standing UC undergoing surveillance colonoscopy with standard definition-white light endoscopy (SD-WLE), high-definition WLE (HD-WLE), narrow band imaging (NBI), or dye-based chromoendoscopy. The primary outcome was the total number of dysplastic lesions. Pairwise and network meta-analysis was performed; ranking was assessed using surface under the cumulative ranking (SUCRA) probabilities. Based on 8 parallel-group RCTs (924 patients), low-quality evidence supports chromoendoscopy over SD-WLE (odds ratio [OR], 2.37; 95% credible interval [CrI], 0.81-6.94) for any dysplasia detection, whereas very low-quality evidence supports using HD-WLE or NBI over SD-WLE (HD-WLE [vs SD-WLE]: OR, 1.21; 95% CrI, 0.30-4.85; NBI: OR, 1.68; 95% CrI, 0.54-5.22). Very low-quality evidence from indirect comparative analysis supports the use of chromoendoscopy over HD-WLE (OR, 1.96; 95% CrI, 0.72-5.34) or NBI (OR, 1.41; 95% CrI, 0.70-2.84) for any dysplasia detection. The number of patients with advanced neoplasia was very small, precluding meaningful analysis. Although we did not find any single technique to be superior, chromoendoscopy is probably more effective than SD-WLE for detecting any dysplasia, and there is low confidence in estimates supporting its use over HD-WLE or NBI. There is very low-quality evidence to inform the comparative efficacy of these interventions in detecting advanced neoplasia or preventing future colorectal cancer. Pragmatic, parallel-group RCTs with longitudinal follow-up are warranted to inform optimal dysplasia surveillance techniques. 10.1093/ibd/izy188_video1izy188.video15789702674001.

Evaluation and Detection of Dysplasia in IBD: the Role of Chromoendoscopy and Enhanced Imaging Techniques.

Patients with ulcerative colitis (UC) and Crohn's disease (CD) colitis are at significantly higher risk for the development of colitis-associated colorectal cancer (CAC), a risk associated with increased duration and extent of disease [1]. CAC in patients with ulcerative colitis and Crohn's colitis arises from dysplastic tissue in the background of mucosal inflammatory changes. Regular surveillance by colonoscopy is a recommended cancer prevention strategy endorsed by the US and European GI societies [2-4]. Until recently, random sampling of the mucosa throughout the colon has been the mainstay of this conventional surveillance. This requires multiple biopsies to be taken and processed, a practice which is time consuming, expensive, and has a low diagnostic yield. The growth pattern of dysplastic tissue is often multifocal and diffuse, and thus, its detection may not be optimal with the use of traditional white light colonoscopy. According to recent studies, most dysplastic lesions appear to be visible to careful endoscopic inspection [5-7]. Thus, the approach focusing on targeted biopsies of any mucosal abnormalities instead of only random biopsies has been advocated [8]. In addition, the detection and further delineation of any mucosal abnormalities are thought to be improved by the application of dyes that highlight more subtle abnormalities known as chromoendoscopy (CE) as well as a new generation endoscopic system with high-definition white light endoscopy (HDWL). The application of CE in patients with long-term UC was deemed to be beneficial based upon the results of previous clinical trials comparing CE with standard definition white light endoscopy (SDWL) [9•, 10•]. However, there are limited data available comparing CE with the currently broadly used high-definition colonoscopies (HDWL) [11•, 12•, 13•]. High-definition (HD) endoscopy uses a high-definition monitor and a high-resolution CCD (charge-coupled device) providing images of substantially higher resolution than standard video endoscopy. Thus, HDWL colonoscopy may be an alternative to CE in IBD surveillance without the need for the extra time and required experience with CE. Further longitudinal studies are necessary to determine the ultimate advantage of chromoendoscopy or lack of the advantages of chromoendoscopy over that of high-definition colonoscopy in detection of dysplasia. Once lesions are identified by HDWL and CE, they can be further evaluated with evolving technologies to perform in vivo microscopy. Small-field technologies such as confocal endomicroscopy (CLE) permit in vivo microscopic assessment of the colonic mucosa. This evolving technology can be utilized in combination with HDWL and CE in selected cases to further define the lesions and assess their histology, and thus, facilitate real-time in vivo diagnosis and decisions regarding resection of lesions. Further studies to determine the applicability of these newer enhanced technologies in evaluation of dysplasia in routine clinical practice are needed.

OC-045 High Definition White Light Endoscopy and I-Scan for small Colonic Polyp Evaluation : Results of the Hiscope Study: Abstract OC-045 Table 1

<h3>Introduction</h3> Standard definition white light endoscopy is inadequate for in-vivo characterisation of small colonic polyps. The ASGE has identified prediction of polyp surveillance intervals and negative predictive value for adenomatous histology of diminutive recto-sigmoid polyps as key targets for new technologies. High definition white light endoscopy is now available but there is little data on it’s use. <h3>Methods</h3> We aimed to examine the in-vivo characterisation accuracy of high definition white light endoscopy (HDWL) plus a novel electronic imaging modality – i-Scan (Pentax, Japan). Patients undergoing colonoscopy through the UK Bowel Cancer Screening Programme were prospectively recruited. All colonoscopies were performed by a single expert endoscopist with extensive experience in in-vivo diagnosis. Procedures were performed with Pentax EC-3890Li 1.2 Megapixel HD+ colonoscopes and EPKi processor. An initial classification &amp; validation exercise was carried out to determine the optimum i-Scan settings for in-vivo diagnosis, and to develop a novel in-vivo diagnosis assessment tool. All polyps &lt; 10mm in size were assessed sequentially with HDWL and i-Scan. Optical magnification was not used. Predicted histology (non-neoplastic, adenoma, cancer) was recorded for both modalities and compared to the final histopathological diagnosis as reported by an expert gastrointestinal pathologist. Predictions were rated as high or low confidence assessments. Results were analysed for sensitivity and specificity for neoplasia, overall accuracy, and negative predictive value for rectosigmoid polyps ≤5 mm as recommended by the ASGE PIVI statement. <h3>Results</h3> 84 patients were recruited, in whom 209 polyps &lt; 10 mm were included. Mean polyp diameter was 4.3mm, median 4mm. 134 polyps were neoplastic and 75 non-neoplastic. There were no significant differences in sensitivity (95.5% vs 97.0%) and specificity (89.3% vs 90.7%) for neoplasia and overall diagnostic accuracy (93.3% vs 94.7%) between HDWL and i-Scan. Negative predictive value for adenomatous histology of rectosigmoid polyps ≤5 mm was 100% with both modalities. Polyp surveillance intervals using in-vivo assessment of diminutive polyps were correct in 95% and 97% of patients with HDWL and i-Scan respectively. <h3>Conclusion</h3> Excellent in vivo diagnostic accuracy, in excess of 90% can be achieved with HDWL alone. No significant gains in accuracy over HDWL were noted with i-Scan when used with a 1.2Megapixel HD colonoscope Both HDWL and i-Scan fulfil the ASGE criteria for ‘resect and discard’ and ‘do not resect’ strategies for diminutive polyps <h3>Disclosure of Interest</h3> None Declared

Tu1482 High Definition White Light Endoscopy and I-SCAN for in-Vivo Characterisation of Small Colonic Polyps: No Need to Push the Button

a conventional image, the lesion was each observed by NBI magnification. The diagnosis of NBI magnification was based on Sano’s classification. Also irregular findings of microvessels including “caliber change of microvessel” (CCM), “long irregular vessel” (LIV) and “decline of microvessel density” (DMD) were analyzed. When type V pit pattern was suspected, the lesion was observed after crystal-violet dye-stain. The diagnosis of chromoendoscopic magnification was based on Kudo’s classification. Both capillary pattern and pit pattern were compared with final histological diagnosis. This study was performed retrospectively and consecutively. Histological diagnosis on resected specimen was determined according to Vienna classification. Submucosal massively invasive cancer (SM-M) was defined as an invasive depth greater than 1000 m. Results: As to histological diagnoses, there were 380 intramucosal cancers, 60 submucosal slightly invasive cancers, and 81 cancers with submucosal massively invasion. The values of the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) and accuracy of type IIIB for the diagnosis of SM-M were 70.4%, 98.6%, 90.5%, 94.8% and 94.3%, respectively. Those of VI highly irregular and VN were 81.5%, 98.4%, 90.4%, 96.7% and 95.8%, respectively. Type IIIB was observed in 19 (73.1%) of 26 protruded type SM-M, 8 (40.0%) of 20 flat type SM-M and 30 (85.7%) of 35 depressed type SM-M. The values of specificity of CCM, LIV and DMD for the diagnosis of SM-M were 99.1%, 99.8% and 99.5%, respectively. CCM was observed in 14 (51.9%) of 26 protruded type SM-M. And DMD were observed in 23 (67.6%) of 35 depressed type SM-M. Conclusion: NBI magnification would have clinical advantage to diagnose the invasion depth of early colorectal cancers. Submucosal massively invasive cancers had characteristic irregular findings that depended on the morphological type. These irregular findings had high specificity for the diagnosis of submucosal massively invasive cancers. Tu1482 High Definition White Light Endoscopy and I-SCAN for in-Vivo Characterisation of Small Colonic Polyps: No Need to Push the Button Peter J. Basford*, Gaius R. Longcroft-Wheaton, Pradeep Bhandari Gastroenterology, Portsmouth Hospitals NHS Trust, Portsmouth, United Kingdom Introduction: Standard definition white light endoscopy is inadequate for in-vivo characterisation of small colonic polyps. Chromoendoscopy and electronic imaging techniques are shown to improve accuracy. The ASGE has identified prediction of polyp surveillance intervals and negative predictive value for adenomatous histology of diminutive recto-sigmoid polyps as key targets for new technologies. High definition white light endoscopy incorporating charge coupled device chips with resolution in excess of 1 million pixels are now available but there is little data on their use. Aims&Methods: We aimed to examine the in-vivo characterisation accuracy of high definition white light endoscopy (HDWL) plus a novel electronic imaging modality i-Scan (Pentax, Japan). Patients undergoing colonoscopy through the UK Bowel Cancer Screening Programme were prospectively recruited. All colonoscopies were performed by a single expert endoscopist with extensive experience in in-vivo diagnosis. Procedures were performed with Pentax EC-3890Li 1.2 Megapixel HD colonoscopes and EPKi processor. An initial classification & validation exercise was carried out to determine the optimum i-Scan settings for in-vivo diagnosis, and to develop a novel in-vivo diagnosis assessment tool. All polyps 10mm in size were assessed sequentially with HDWL and i-Scan. Optical magnification was not used. Predicted histology (non-neoplastic, adenoma, cancer) was recorded for both modalities and compared to the final histopathological diagnosis as reported by an expert gastrointestinal pathologist. Predictions were rated as high or low confidence assessments. Results were analysed for sensitivity and specificity for neoplasia, overall accuracy, and negative predictive value for rectosigmoid polyps 5mm as recommended by the ASGE PIVI statement. Results: 84 patients were recruited, in whom 209 polyps 10mm were included. Mean polyp diameter was 4.3mm, median 4mm. 134 polyps were neoplastic and 75 non-neoplastic. There were no significant differences in sensitivity (95.5% vs 97.0%) and specificity (89.3% vs 90.7%) for neoplasia and overall diagnostic accuracy (93.3% vs 94.7%) between HDWL and i-Scan. Negative predictive value for adenomatous histology of rectosigmoid polyps 5mm was 100% with both modalities. Polyp surveillance intervals using in-vivo assessment of diminutive polyps were correct in 95% and 97% of patients with HDWL and i-Scan respectively. Conclusion: 1) Excellent in vivo diagnostic accuracy, in excess of 90% can be achieved with HDWL alone.2) No significant gains in accuracy over HDWL were noted with i-Scan when used with a 1.2Megapixel HD colonoscope therefore, there is no need to push the button or spray dye to improve accuracy. 3) Both HDWL and i-Scan fulfill the ASGE criteria for ‘resect and discard’ and ‘do not resect’ strategies for diminutive polyps

Comparison of high definition with standard white light endoscopy for detection of dysplastic lesions during surveillance colonoscopy in patients with inflammatory bowel disease

IntroductionDysplasia in colonic inflammatory bowel disease (IBD) is often multifocal and flat, making it easy for significant lesions to be overlooked. Dye spraying the mucosal surface is believed to enhance...

Use of Narrow Band Imaging (NBI) in Photodynamic Therapy (PDT) for Barrettʼs High Grade Dysplasia (BE+HGD) and Mucosal Carcinoma (IMC)

Purpose: Endoscopic ablation using techniques such as porfimer sodium photodynamic therapy are increasingly used to treat patients with Barrett's dysplasia and mucosal carcinoma. However, PDT is associated with the risk of stricture in areas of overlapping light exposure. Use of fiber centering balloons has been promoted to improve light distribution. Narrow Band Imaging (NBI) uses spectrally narrowed optical filters and a monochromatic CCD to view the mucosal microvasculature. We hypothesized that NBI might permit improved visualization of the laser light fiber during PDT procedures and thereby improve the accuracy of light application. The aim of this study was to evaluate laser light application during PDT procedures using NBI and then compare the rates of stricture formation with previous PDT procedures performed using conventional white light endoscopy. Methods: After IRB approval, consecutive patients undergoing endoscopic ablation treatment with Ps-PDT for BE+HGD or IMC were compared for visualization and determination of laser fiber and mucosal location using standard definition white light endoscopy (Olympus GIF-Q180), high definition white light endoscopy (Olympus XGIF-H160Y2), and HD-NBI (Olympus XGIF-H160Y2, 415 and 540 nm). The incidence of post-Ps-PDT stricture formation (dysphagia associated with mucosal scarring or narrowing) was compared with historical controls. Results: Narrow Band Imaging used to guide porfimer sodium photodynamic therapy in 15 patients (9 BE+HGD pts, 6 IMC pts). All patients were men; mean age 67 yrs, range 59–76 yrs. The mean BE segment was 4 cm; range 1–10 cm. In all cases using a standard white-light endoscope, PDT laser light (630nm, Diomed Inc.) induced CCD video chip “white out” preventing direct visualization and positioning of the laser fiber. HD white light endoscopes (without NBI mode activated) visualized the light fiber position but not mucosal location. In each case, the use of HD NBI permitted real-time, continuous determination of the laser light fiber position and mucosal location. Strictures occurred in 2/15 patients (13%) after NBI Ps-PDT compared with 22–25% stricture rate in historical controls. Conclusions: The use of Narrow Band Imaging during PDT for Barrett's high grade dysplasia or mucosal carcinoma permitted the continuous determination of laser fiber position and mucosal location without the need for a fiber-centering balloon device and may reduce the rate of post ablation stricture.