A Randomized Trial Comparing High Definition Colonoscopy Alone With High Definition Dye Spraying and Electronic Virtual Chromoendoscopy for Detection of Colonic Neoplastic Lesions During IBD Surveillance Colonoscopy.

OBJECTIVES: Dye spraying chromoendoscopy (DCE) is recommended for the detection of colonic neoplastic lesions in inflammatory bowel disease (IBD). The majority of neoplastic lesions are visible endoscopically and therefore targeted biopsies are appropriate for surveillance colonoscopy. To compare three different techniques for surveillance colonoscopy to detect colonic neoplastic lesions in IBD patients: high definition (HD), (DCE), or virtual chromoendoscopy (VCE) using iSCAN image enhanced colonoscopy. METHODS: A randomized non-inferiority trial was conducted to determine the detection rates of neoplastic lesions in IBD patients with longstanding colitis. Patients with inactive disease were enrolled into three arms of the study. Endoscopic neoplastic lesions were classified by the Paris classification and Kudo pit pattern, then histologically classified by the Vienna classification. RESULTS: A total of 270 patients (55% men; age range 20-77 years, median age 49 years) were assessed by HD (n=90), VCE (n=90), or DCE (n=90). Neoplastic lesion detection rates in the VCE arm was non-inferior to the DCE arm. HD was non-inferior to either DCE or VCE for detection of all neoplastic lesions. In the lesions detected, location at right colon and the Kudo pit pattern were predictive of neoplastic lesions (OR 6.52 (1.98-22.5 and OR 21.50 (8.65-60.10), respectively). CONCLUSIONS: In this randomized trial, VCE or HD-WLE is not inferior to dye spraying colonoscopy for detection of colonic neoplastic lesions during surveillance colonoscopy. In fact, in this study HD-WLE alone was sufficient for detection of dysplasia, adenocarcinoma or all neoplastic lesions.

Development and validation of the SIMPLE endoscopic classification of diminutive and small colorectal polyps.

BACKGROUND: Prediction of histology of small polyps facilitates colonoscopic treatment. The aims of this study were: 1) to develop a simplified polyp classification, 2) to evaluate its performance in predicting polyp histology, and 3) to evaluate the reproducibility of the classification by trainees using multiplatform endoscopic systems. METHODS: In phase 1, a new simplified endoscopic classification for polyps - Simplified Identification Method for Polyp Labeling during Endoscopy (SIMPLE) - was created, using the new I-SCAN OE system (Pentax, Tokyo, Japan), by eight international experts. In phase 2, the accuracy, level of confidence, and interobserver agreement to predict polyp histology before and after training, and univariable/multivariable analysis of the endoscopic features, were performed. In phase 3, the reproducibility of SIMPLE by trainees using different endoscopy platforms was evaluated. RESULTS: Using the SIMPLE classification, the accuracy of experts in predicting polyps was 83 % (95 % confidence interval [CI] 77 % - 88 %) before and 94 % (95 %CI 89 % - 97 %) after training (P â€Š= 0.002). The sensitivity, specificity, positive predictive value, and negative predictive value after training were 97 %, 88 %, 95 %, and 91 %. The interobserver agreement of polyp diagnosis improved from 0.46 (95 %CI 0.30 - 0.64) before to 0.66 (95 %CI 0.48 - 0.82) after training. The trainees demonstrated that the SIMPLE classification is applicable across endoscopy platforms, with similar post-training accuracies for narrow-band imaging NBI classification (0.69; 95 %CI 0.64 - 0.73) and SIMPLE (0.71; 95 %CI 0.67 - 0.75). CONCLUSIONS: Using the I-SCAN OE system, the new SIMPLE classification demonstrated a high degree of accuracy for adenoma diagnosis, meeting the ASGE PIVI recommendations. We demonstrated that SIMPLE may be used with either I-SCAN OE or NBI.

Development and reliability of the new endoscopic virtual chromoendoscopy score: the PICaSSO (Paddington International Virtual ChromoendoScopy ScOre) in ulcerative colitis.

BACKGROUND AND AIMS: Endoscopic inflammation and healing are important therapeutic endpoints in ulcerative colitis (UC). We developed and validated a new electronic virtual chromoendoscopy (EVC) score that could reflect the full spectrum of mucosal and vascular changes including mucosal healing in UC. METHODS: Eight participants reviewed a 60-minute training module outlining 3 different i-SCAN modes demonstrating the entire spectrum of inflammatory mucosal and vascular changes in UC. Performance characteristics in endoscopic scoring and predicting the histologic inflammation with EVC (i-SCAN) by using 20 video clips before (pre-test) and after (post-test) were evaluated. Exploratory univariate factor analysis was performed on Paddington International Virtual Chromoendoscopy Score (PICaSSO) covariates for mucosal and vascular score separately. Subsequently, a proportional odds logistic regression model for the prediction of histologic scores was analyzed. RESULTS: The interobserver agreement for Mayo endoscopic score in the pre-test (κ = .85; 95% CI, .78-.90) and the post-test (κ = .85; 95% CI, .77-.90) evaluation were very good. This was also true for the Ulcerative Colitis Endoscopic Index of Severity in the pre-test and post-test score interobserver agreement (κ = .86; 95% CI, .77-.92; and κ = .84; 95% CI, .75-.91, respectively). The interobserver agreement of the PICaSSO endoscopic score was very good in the pre-test and post-test evaluations (κ = .92; 95% CI, .87-.96; and κ = .89; 95% CI, .84-.94, respectively). The accuracy of the overall PICaSSO in assessing histologic abnormalities and inflammation by Harpaz score was 57% (95% CI, 48%-65%), by Robarts Histological Index 72% (95% CI, 64%-79%), and by the extent, chronicity, activity, plus system (full spectrum of histologic changes) 83% (95% CI, 76%-88%). CONCLUSIONS: The EVC score "PICaSSO" showed very good interobserver agreement. The new EVC score may be used to define the endoscopic findings of mucosal and vascular healing in UC and reflected the full spectrum of histologic changes.

Beyond white light: optical enhancement in conjunction with magnification colonoscopy for the assessment of mucosal healing in ulcerative colitis.

Background and study aim The I-SCAN optical enhancement (OE) system with magnification is a recently introduced combination of optical and digital electronic virtual chromoendoscopy, which enhances mucosal and vascular details. The aim of this pilot study was to investigate the use of I-SCAN OE in the assessment of inflammatory changes in ulcerative colitis (UC). Patients and methods A total of 41 consecutive patients with UC and 9 control patients were examined by I-SCAN OE (Pentax Medical, Tokyo, Japan). Targeted biopsies of the imaged areas were obtained. A new optical enhancement score focusing on mucosal and vascular changes was developed. The diagnostic accuracy of I-SCAN OE was calculated against histology using two UC histological scores - Robarts Histopathology Index (RHI) and ECAP (Extent, Chronicity, Activity, Plus additional findings). Results The overall I-SCAN OE score correlated with ECAP (r = 0.70; P < 0.001). The accuracy of the overall I-SCAN OE score to detect abnormalities by ECAP was 80 % (sensitivity 78 %, specificity 100 %). I-SCAN OE vascular and mucosal scores correlated with ECAP (r = 0.65 and 0.71, respectively; P < 0.001). The correlation between overall I-SCAN OE score and RHI was r = 0.61 (P < 0.01), and the accuracy to detect abnormalities by RHI was 68 % (sensitivity 78 %, specificity 50 %). The majority of patients with Mayo 0 had abnormalities on I-SCAN OE. Conclusion In UC, the new I-SCAN OE technology accurately identified mucosal inflammation, and correlated well with histological scores of chronic and acute changes.

Chemical footprints of harmattan dust and traffic corridor particulates monitored at two environmentally distinct geopolitical zones in Nigeria.

Harmattan dust and traffic-related pollution have been a serious environmental concern in the West African sub-region. In order to further contribute to the understanding of ambient levels of atmospheric pollution and chemical composition in the region, this study monitored harmattan dust and traffic-related particulate matter at four locations across southwestern (Ile-Ife) and north-western (Zaria) geo-political zones of Nigeria. The collected samples were characterized for their chemical composition using Energy-Dispersive X-Ray Fluorescence spectrometer equipped with an optimized secondary target x-ray excitation conditions (Al, CaF2, Fe, Ge, Zr, Mo, Ag, Al2O3). The objectives are to assess spatio-temporal mass concentrations, chemical footprints, enrichment factors, elemental correlations, and ratios at all locations. The X-ray analytical method was validated with a NIST SRM 2783 air particulate standard, and detection limits for each chemical specie were determined. Validation results showed good reproducibility of the certified reference material with relative standard deviations of the elements much lower by about 1-13% than the corresponding reference values. Mass concentrations reached up to 2200 µgm-3 in the north and 1500 µgm-3 in the south. The range of mean concentration of crustal marker elements were Al (5-27 µgm-3), Si (5-856 µgm-3), Ca (0.78-13 µgm-3), and Fe (2-13 µgm-3), and were most abundant during the harmattan particularly in the southwestern region. Highest mean concentration values of 380, 810, and 420 ngm-3 were recorded for Cr, Cu, and Pb respectively at the traffic corridor which also recorded the highest enrichment factors. Black carbon and elemental concentrations contributed between 1 to 54% and 9 to 94% across the locations respectively. Backward trajectories of atmospheric flow over the locations showed two dominant sources; dust laden source from the Sahara desert and maritime flow over the Gulf of Guinea. This study found that chemical footprints (Al, Si, K, Ca, Ti, and Fe) of harmattan-related dust were more correlated (r2 between 0.88 and 0.99) than those attributed to dust re-suspension at the traffic location.