Virtual Chromoendoscopy Techniques Research Articles

How to assess endoscopic disease activity in ulcerative colitis in 2022.

Endoscopic remission currently represents an important therapeutic goal to reach in the management of patients with ulcerative colitis (UC). The diagnostic and prognostic role of endoscopy, which remains the gold standard for the assessment of disease activity, has been widely reported. Despite being unvalidated and suboptimal at measuring remission, the most widely used scoring system is the Mayo endoscopic subscore (MES). The UC Endoscopic Index of Severity and the UC Colonoscopic Index of Severity represent recent performing indices for the assessment of endoscopic disease activity in the field of white-light endoscopy. However, their use is still very limited, both in trials and clinical practice. The most recent Paddington international virtual chromoendoscopy score was the first validated index to assess vascular and mucosal features in UC using a virtual chromoendoscopy technique and showed good performance. This narrative review aims to describe these validated endoscopic scoring indices, focusing on the development methodology, and the strengths and weaknesses of each one in comparison with the MES for the assessment of UC activity.

Innovative Diagnostic Endoscopy in Inflammatory Bowel Diseases: From High-Definition to Molecular Endoscopy.

High-definition endoscopy is one essential step in the initial diagnosis of inflammatory bowel disease (IBD) characterizing the extent and severity of inflammation, as well as discriminating ulcerative colitis (UC) from Crohn's disease (CD). Following general recommendations and national guidelines, individual risk stratification should define the appropriate surveillance strategy, biopsy protocol and frequency of endoscopies. Beside high-definition videoendoscopy the application of dyes applied via a spraying catheter is of additional diagnostic value with a higher detection rate of intraepithelial neoplasia (IEN). Virtual chromoendoscopy techniques (NBI, FICE, I-scan, BLI) should not be recommended as a single surveillance strategy in IBD, although newer data suggest a higher comparability to dye-based chromoendoscopy than previously assumed. First results of oral methylene blue formulation are promising for improving the acceptance rate of classical chromoendoscopy. Confocal laser endomicroscopy (CLE) is still an experimental but highly innovative endoscopic procedure with the potential to contribute to the detection of dysplastic lesions. Molecular endoscopy in IBD has taken application of CLE to a higher level and allows topical application of labeled probes, mainly antibodies, against specific target structures expressed in the tissue to predict response or failure to biological therapies. First pre-clinical and in vivo data from label-free multiphoton microscopy (MPM) are now available to characterize mucosal and submucosal inflammation on endoscopy in more detail. These new techniques now have opened the door to individualized and highly specific molecular imaging in IBD in the future and pave the path to personalized medicine approaches. The quality of evidence was stated according to the Oxford Center of evidence-based medicine (March 2009). For this review a Medline search up to January 2021 was performed using the words “inflammatory bowel disease,” “ulcerative colitis,” “crohn's disease,” “chromoendoscopy,” “high-definition endoscopy,” “confocal laser endomicroscopy,” “confocal laser microscopy,” “molecular imaging,” “multiphoton microscopy.”

The Value of Virtual Chromoendoscopy in the Workup of Patients with Head and Neck Squamous Cell Carcinoma.

Second primary tumors (SPTs) significantly increase the mortality in patients with head and neck squamous cell carcinomas (HNSCCs). Virtual chromoendoscopy (VCE) could complement or replace lugol chromoendoscopy (LCE) for early esophageal second primary tumor (ESPT) detection. An overview of the existing techniques and their diagnostic performance in early detection of esophageal squamous cell neoplasms is provided. Nowadays, LCE is the golden standard to detect ESPTs. Recently, multiple new VCE techniques have been developed. Especially narrow-band imaging (NBI) is promising. It shows similar sensitivity to LCE, but a significantly higher specificity. Patients with HNSCC are prone to develop ESPTs, both synchronous and metachronous, with a substantial negative impact on survival rates. Therefore, active screening and follow-up is necessary. LCE is an effective screening method, but has some disadvantages. Countering these drawbacks, NBI shows a high potential in early ESPT detection in high-risk patients. Additional multicenter studies are needed to compare diagnostic performance and cost-effectiveness of NBI and other VCE techniques with LCE.

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.

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. 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. 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. 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.

CD31-positive microvessel density within adenomas of Lynch Syndrome patients is similar compared to adenomas of non-Lynch patients.

Background and study aims Microsatellite instability accelerates colorectal cancer development in patients with Lynch syndrome (LS). Previous research showed that virtual chromoendoscopy increases detection of adenomas during colonoscopy surveillance of patients with LS. Because previous research revealed that Lynch patients have an increased vascular network in the oral mucosa, we hypothesized that increased vascularization of LS-associated adenomas is the cause of better detection with virtual chromoendoscopy. Patients and methods In this pilot study, patients with LS having a proven germline mutation were selected from two tertiary referral hospitals and non-LS patients from an outpatient colonoscopy center. Adenomas from patients with LS were exactly matched in size and histology with adenomas from non-LS patients. Initial adenoma diagnosis was confirmed by a specialist pathologist. All adenomas were stained with CD31 and adenomatous tissue was annotated by the specialist pathologist. Image analysis of CD31-positive microvessel density was conducted using FIJI software. Results Colonoscopy of 63 patients with LS and 24 non-LS patients provided 40 adenomas that could be exactly matched in size and histology. In image-analysis, the CD31-positive microvessel density (2.49 % vs. 2.47 %, P = 0.96), the average size of CD31-positive structures (514 μm 2 vs. 523 μm 2 , P = 0.26) nor the amount of vascular structures per mm 2 (183 vs. 176, P = 0.50) differed between adenomas of LS patients and non-Lynch patients. Conclusion The outcomes of this pilot case-control study did not provide further insights into the mechanism of increased adenoma detection in LS patients using virtual chromoendoscopy techniques.

Virtual chromoendoscopy improves the diagnostic yield of small bowel capsule endoscopy in obscure gastrointestinal bleeding

BackgroundSmall bowel capsule endoscopy represents the initial investigation for obscure gastrointestinal bleeding. Flexible spectral imaging colour enhancement (FICE) is a virtual chromoendoscopy technique designed to enhance mucosal lesions, available in different settings according to light wavelength – FICE1, 2 and 3. AimsTo compare the diagnostic yield of FICE1 and white light during capsule endoscopy in patients with obscure gastrointestinal bleeding. MethodsRetrospective single-centre study including 60 consecutive patients referred for small bowel capsule endoscopy for obscure gastrointestinal bleeding. Endoscopies were independently reviewed in FICE1 and white light; findings were then reviewed by another researcher, establishing a gold standard. Diagnostic yield was defined as the presence of lesions with high bleeding potential (P2) angioectasias, ulcers or tumours. ResultsDiagnostic yield using FICE1 was significantly higher than white light (55% vs 42%, p=0.021). A superior number of P2 lesions was detected with FICE1 (74 vs 44, p=0.003), particularly angioectasias (54 vs 26, p=0.002), but not ulcers or tumours. ConclusionsFICE1 was significantly superior to white light, resulting in a 13% improvement in diagnostic yield, and potentially bleeding lesions particularly angioectasias were more often observed. Our results support the use of FICE1 while reviewing small bowel capsule endoscopy for obscure gastrointestinal bleeding.

Is virtual chromoendoscopy useful in the evaluation of subtle ulcerative small-bowel lesions detected by video capsule endoscopy?

Background: The identification of subtle small-bowel mucosal lesions by video capsule endoscopy (VCE) can be challenging. Virtual chromoendoscopy techniques, based on narrowing the bandwidth of conventional white light endoscopic imaging (WLI), were developed to improve the analysis of mucosal patterns. However, data on the already-implemented Flexible spectral Imaging (or Fujinon Intelligent) Color Enhancement (FICE) software application in VCE are limited. Materials and methods: An evaluation of 250 difficult-to-interpret small-bowel ulcerative and 50 artifact lesions selected from 64 VCE recordings was conducted by four experienced VCE readers in two steps: initially as WLI, then with the addition of all available virtual chromoendoscopy pre-sets (FICE 1, 2, and 3 and Blue mode). The readers labeled them as real or false ulcerative lesions and rated the usefulness of each of the pre-sets. Results: Between the first (WLI-only) and second (virtual chromoendoscopy-aided) readings, in terms of accuracy there was a global 16.5 % (95 % confidence interval [95 %CI] 13.6 – 19.4 %) improvement (P < 0.001), derived from a 22 % [95 %CI 18.9 – 25.1 %] improvement in the evaluation of true ulcerative images (P < 0.001) and an 11 % (95 %CI 4.1 – 17.7 %) decrease in the evaluation of false ulcerative ones (P = 0.003). The FICE 1 and 2 pre-sets were rated as most useful. Conclusion: The application of virtual chromoendoscopy for VCE is useful to better categorize difficult-to-interpret small-bowel mucosal ulcerative lesions. However, care must be taken, and individual images should be evaluated only as part of a sequence in a recording because the technology can also mistakenly guide to the incorrect interpretation of artifacts as ulcerative lesions.

Advanced endoscopic imaging to improve adenoma detection.

Advanced endoscopic imaging is revolutionizing our way on how to diagnose and treat colorectal lesions. Within recent years a variety of modern endoscopic imaging techniques was introduced to improve adenoma detection rates. Those include high-definition imaging, dye-less chromoendoscopy techniques and novel, highly flexible endoscopes, some of them equipped with balloons or multiple lenses in order to improve adenoma detection rates. In this review we will focus on the newest developments in the field of colonoscopic imaging to improve adenoma detection rates. Described techniques include high-definition imaging, optical chromoendoscopy techniques, virtual chromoendoscopy techniques, the Third Eye Retroscope and other retroviewing devices, the G-EYE endoscope and the Full Spectrum Endoscopy-system.

The good lies so near - invivo diagnosis of colonic polyps.

The good lies so near - invivo diagnosis of colonic polyps.

504 Virtual Chromoendoscopy With I-Scan for Diagnosis of Mucosal Healing in Patients With Inflammatory Bowel Disease - a Randomized Double-Blind Controlled Study

Increased vascular permeability and angiogenesis plays a crucial role in the pathogenesis of inflammatory bowel diseases (IBD). Previously, magnifying endoscopy and chromoendoscopy have been shown to be reliable tools for predicting histological assessment of disease severity in patients with mild or even inactive disease. i-scan was recently introduced as a novel computed virtual chromoendoscopy technique which enables a clear visualization of the mucosal vascular pattern within the gastrointestinal tract.

Su1456 The Learning Curve of Virtual Chromoendoscopy With I-SCAN for Prediction of Hyperplastic and Adenomatous Colorectal Lesions - a Multicenter Study

I-scan was recently introduced as a new computed virtual chromoendoscopy technique which enables high-definition imaging of lesions with improved tissue contrast. Previous studies have shown that i-scan yield in an improved detection rate of colorectal lesions. The learning curve for interpretation of i-scan images is unknown.

P111 “EARS” (Erlanger Activity Related Score) of IBD: A new tool that allows accurate in vivo assessment of inflammatory activity in ulcerative colitis

Background: Increased vascular permeability and angiogenesis play a crucial role in the pathogenesis of inflammatory bowel disease (IBD). Previously, magnifying endoscopy and chromoendoscopy have been shown to be reliable tools for predicting histological assessment of severity in patients with mild or even inactive disease. i-scan (Pentax, Tokyo, Japan) was recently introduced as a novel computed virtual chromoendoscopy technique which enables a clear visualization of the mucosal vascular pattern within the gastrointestinal tract. Aim was to determine whether i-scan has the potential to enhance assessment of disease severity and extent in patients with mild or inactive IBD in comparison to high-definition white light endoscopy (HD-WL). Methods: Consecutive patients with IBD were randomly assigned at a 1:1 ratio to undergo colonoscopy with HD-WL (Group 1) or i-scan (Group 2). The mucosal vascular pattern and any mucosal abnormalities were recorded. Inflammation in ulcerative colitis was recorded according to Mayo ulcerative endoscopic score and in Crohn’s disease according to Crohn’s Disease Endoscopic Index of Severity (CDEIS). Subsequent to endoscopic characterization targeted biopsies were obtained from every segment for subsequent histopathological analysis of disease activity. Results: Overall, 100 patients were screened to participate in this study of whom 78 patients (HD white light, n = 39; i-scan, n = 39) completed the study protocol thereby matching the previously calculated sample size. Average duration of the examination was 18 minutes in group A and 20.5 minutes in group B which was not statistically significant. When comparing the endoscopic prediction of inflammatory extent and activity with the histological results an overall agreement of 51.28% and 56.41% (group A) and 92.31% and 89.74% (group B) was found, respectively. These differences were statistically significant (p = 0.0009 and p = 0.011). Conclusions: The present study indicates that i-scan significantly improves the diagnosis of the severity and extent of mucosal inflammation in patients with IBD. This newly developed imaging technique will therefore have important implications for diagnostic and therapeutic interventions in patients with IBD.

Colonoscopic Surveillance in Inflammatory Bowel Disease: State of the Art Reduction of Biopsies

Longstanding colitis in inflammatory bowel disease (IBD) is associated with an increased risk for intraepithelial neoplasia (IN). White light endoscopy (WLE) with 40–50 random biopsies has been promoted for surveillance but may miss a significant proportion of lesions. In addition, the yield of random biopsies to detect IN is low, and random biopsies are expensive, labor-intensive and distract from scrutinizing the colon. Chromoendoscopy with targeted biopsies has proven its superiority over WLE in multiple randomized trials. It has been incorporated into many national and international guidelines. Virtual chromoendoscopy techniques carry the potential to provide contrast enhancement without spraying color onto the mucosa. However, trials using virtual chromoendoscopy techniques have failed to show enhanced detection of IN compared to WLE so far. Autofluorescence imaging has the potential to serve as a red-flag technique for macroscopic detection of IN by screening large mucosal areas in IBD. Confocal laser endomicroscopy (CLE) is able to provide intravital microscopic diagnosis on a cellular level. In a first study, CLE had a high accuracy for prediction of neoplasia. Together, all these modern endoscopy approaches aim at overcoming shortcomings of WLE in a move towards abandoning untargeted random biopsies for targeted, ‘smart’ biopsies. Future efforts to optimize endoscopic surveillance in inflammatory colitis should aim at identifying patients at high risk of developing IN, tailor individual surveillance intervals, use red-flag techniques for IN detection and may even predict response to tailored therapy.

The endoscopic diagnosis of nonerosive reflux disease using flexible spectral imaging color enhancement image: a feasibility trial

Nonerosive reflux disease (NERD) is classified into grade M (minimal change, endoscopically; erythema without sharp demarcation, whitish turbidity, and/or invisibility of vessels due to these findings) and grade N (normal) in the modified Los Angeles classification system in Japan. However, the classification of grades M and N NERD is not included in the original Los Angeles system because interobserver agreement for the conventional endoscopic diagnosis of grades M or N NERD is poor. Flexible spectral imaging color enhancement (FICE) is a virtual chromoendoscopy technique that enhances mucosal and vascular visibility. The aim of this study is to evaluate whether the endoscopic diagnosis of grades M or N NERD using FICE images is feasible. Between April 2006 and May 2008, 26 NERD patients and 31 controls were enrolled in the present study. First, an experienced endoscopist assessed the color pattern of minimal change in FICE images using conventional endoscopic images and FICE images side-by-side and comparing the proportion of minimal change between the two groups. Second, three blinded endoscopists assessed the presence or absence of minimal change in both groups using conventional endoscopic images and FICE images separately. Intraobserver variability was compared using McNemar's test, and interobserver agreement was described using the kappa value. Minimal changes, such as erythema and whitish turbidity, which were detected using conventional endoscopic images, showed up as navy blue and pink-white, respectively, in color using FICE images in the present FICE mode. The NERD group had a higher proportion of minimal change, compared with the control group (77% and 48%, respectively) (P= 0.033). In all three readers, the detection rates of minimal change using FICE images were greater than those using conventional endoscopic images (P= 0.025, <0.0001, and 0.034 for readers A, B, and C, respectively). The kappa values for all pairs of three readers using FICE images were between 0.683 and 0.812, while those using conventional endoscopic images were between 0.364 and 0.624. Thus, the endoscopic diagnosis of grades M or N NERD using FICE images is feasible and may improve interobserver agreement.

Techniques endoscopiques pour le diagnostic de l’endobrachyœsophage : place de la chromo-endoscopie et de l’acide acétique

Screening for complications of neoplastic Barrett's oesophagus requires a tedious blind standardized protocol biopsies quadrant every 1 to 2cm depending on the morphology of the Barrett's epithelium (Protocol of Seattle). To achieve that biopsies targeted to areas suspicious of dysplasia, a method of high sensitivity is required. Chromoendoscopy has been developed in this direction. Acetic acid combined with high resolution endoscopy and zooming represents an aid in the preparation of the oesophageal mucosa for visualization of suspicious anomalies. It is safe, cheap and easy to use. Acetic acid has proven its value in improving the visibility of the pit pattern. Several vital dyes have been tested, including methylene blue, indigo carmine and crystal violet, with mixed results. The FICE(®) and NBI(®), immediate, reversible and attractive virtual chromoendoscopy techniques represent interesting tools for improving sensitivity in screening for Barrett's oesophagus and its complications. Confocal endomicroscopy, which is similar as a "per-endoscopic real time histological examination", seems to be equally a promising technique in detection of Barrett's oesophagus associated neoplasia. But these tools which are capable of improvement so far, have not proved their use on a large population. For this, the systematic biopsy protocol Seattle remains the "gold standard" in monitoring the Barrett's oesophagus.

Double-balloon enteroscopy-assisted virtual chromoendoscopy for small-bowel disorders – a case series

The Fujinon intelligent color enhancement (FICE) system is a new, virtual chromoendoscopy technique that enhances mucosal visibility. The aim of this study was to assess the utility of double-balloon enteroscopy (DBE) with FICE technology (EPX-4400 processor, Japan) for the characterization of various small-bowel diseases. Overall, a total of 574 endoscopic pictures were obtained and analyzed. FICE was found to be a helpful method for the evaluation of adenomatous small-bowel polyps and angiodysplasias. Its use for the characterization of celiac and Crohn's disease appears to be limited. Overall, FICE may become a useful method that aids in characterization and provides new insights to small-bowel pathologies.