National Institute of Health Research (NIHR) Birmingham, Biomedical Research Centre (BRC), University of Birmingham, Birmingham, United Kingdom; Liver Unit, University Hospitals Birmingham Queen Elizabeth, Birmingham, United Kingdom; Department of Gastroenterology, University Hospitals Birmingham Queen Elizabeth, Birmingham, United Kingdom; Institute of Translational Medicine, Institute of Immunology and Immunotherapy Birmingham, United kingdom.
Department of Medicine, Division of Gastroenterology, HSK Hospital, Wiesbaden, Germany.
Gastrointest Endosc. 2018 Jul;88(1):95-106.e2. doi: 10.1016/j.gie.2018.02.044. Epub 2018 Mar 13.
Electronic virtual chromoendoscopy (EVC) can demonstrate ongoing disease activity in ulcerative colitis (UC), even when Mayo subscores suggest healing. However, applicability of EVC technology outside the expert setting has yet to be determined.
Fifteen participants across 5 centers reviewed a computerized training module outlining high-definition and EVC (iScan) colonoscopy modes. Interobserver agreement was then tested (Mayo score, Ulcerative Colitis Endoscopic Index of Severity [UCEIS], and the Paddington International Virtual Chromoendoscopy Score [PICaSSO] for UC), using a colonoscopy video library (30 cases reviewed pretraining and 30 post-training). Knowledge sustainability was retested in a second round (42 cases; 9/15 participants), 6 months after training provision.
Pretraining intraclass correlation coefficients (ICC) were good for the Mayo endoscopic subscore (ICC, .775), UCEIS scoring erosions/ulcers (ICC, .770), and UCEIS overall (ICC, .786) and for mucosal (ICC, .754) and vascular components of PICaSSO (ICC, .622). For the vascular components of UCEIS, agreement was only moderate (ICC, .429) and did not enhance post-training (ICC, .417); conversely, use of PICaSSO improved post-training (mucosal ICC, .848; vascular, .746). Histologic correlation using the New York Mt. Sinai System was strong for both PICaSSO components (Spearman's ρ for mucosal: .925; vascular, .873; P < .001 for both). Moreover, accuracy in specifically discriminating quiescent from mild histologic strata was strongest for PICaSSO (area under the receiver operating characteristic curve [AUROC] for mucosal, .781; vascular, .715) compared with Mayo (AUROC, .708) and UCEIS (AUROC for UCEIS overall, .705; vascular, .562; bleeding, .645; erosions/ulcers, .696). Inter-rater reliability for PICaSSO was sustained by round 2 participants (round 1 and 2 ICC for mucosal, .873 and .869, respectively; vascular, .715 and .783, respectively), together with histologic correlation (ρ mucosal, .934; vascular, .938; P < .001 for both).
PICaSSO demonstrates good interobserver agreement across all levels of experience, providing excellent correlation with histology. Given the ability to discriminate subtle endoscopic features, PICaSSO may be applied to refine stratified treatment paradigms for UC patients.
电子虚拟染色内镜（EVC）可显示溃疡性结肠炎（UC）的活动性病变，即使 Mayo 亚评分提示愈合。然而，EVC 技术在专家环境之外的适用性尚未确定。
来自 5 个中心的 15 名参与者学习了一个计算机化的培训模块，该模块概述了高清和 EVC（iScan）结肠镜模式。然后，使用结肠镜视频库（预培训 30 例，培训后 30 例）测试了观察者间的一致性（Mayo 评分、溃疡性结肠炎内镜严重程度指数[UCEIS]和溃疡性结肠炎国际虚拟染色评分[PICaSSO]）。在提供培训后的 6 个月，第二轮（42 例；15 名参与者中的 9 名）测试了知识的可持续性。
预培训的组内相关系数（ICC）对于 Mayo 内镜亚评分（ICC，.775）、UCEIS 评分侵蚀/溃疡（ICC，.770）和 UCEIS 整体（ICC，.786）以及黏膜（ICC，.754）和 PICaSSO 的血管成分（ICC，.622）均良好。对于 UCEIS 的血管成分，一致性仅为中度（ICC，.429），且培训后无改善（ICC，.417）；相反，PICaSSO 的使用培训后得到改善（黏膜 ICC，.848；血管，.746）。使用纽约 Mt. Sinai 系统的组织学相关性对于 PICaSSO 的两个成分均很强（黏膜 Spearman ρ：.925；血管，.873；P均<0.001）。此外，PICaSSO 特别区分静止期和轻度组织学分层的准确性最强（黏膜的受试者工作特征曲线下面积[AUROC]：.781；血管，.715），与 Mayo（AUROC：.708）和 UCEIS（UCEIS 整体的 AUROC：.705；血管，.562；出血，.645；侵蚀/溃疡，.696）相比。第二轮参与者的 PICaSSO 间评分可靠性得以维持（黏膜的第 1 轮和第 2 轮 ICC，分别为.873 和.869；血管，分别为.715 和.783），同时也具有组织学相关性（ρ黏膜，.934；血管，.938；P均<0.001）。
PICaSSO 在所有经验水平均具有良好的观察者间一致性，与组织学具有极好的相关性。鉴于其能够区分细微的内镜特征，PICaSSO 可用于改善 UC 患者的分层治疗方案。
