Background and Aims

The Seattle protocol for endoscopic Barrett’s esophagus (BE) surveillance samples a small portion of the mucosal surface area, risking a potentially high miss rate of early neoplastic lesions. We assessed whether the new iScan Optical Enhancement system (OE) improves the detection of early BE-associated neoplasia compared with high-definition white-light endoscopy (HD-WLE) in both expert and trainee endoscopists to target sampling of suspicious areas. Such a system may both improve early neoplasia detection and reduce the need for random biopsies.

Methods

A total of 41 patients undergoing endoscopic BE surveillance from January 2016 to November 2017 were recruited from 3 international referral centers. Matched still images in both HD-WLE (n = 130) and iScan OE (n = 132) were obtained from endoscopic examinations. Two experts, unblinded to the videos and histology, delineated known neoplasia, forming a consensus criterion standard. Seven expert and 7 trainee endoscopists marked 1 position per image where they would expect a target biopsy to identify dysplastic tissue. The same expert panel then reviewed magnification images and, using a previously validated classification system, attempted to classify mucosa as dysplastic or nondysplastic, based on the mucosal and vascular (MV) patterns observed on magnification endoscopy. Diagnostic accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated. Improvements in dysplasia detection in HD-WLE versus OE and interobserver agreement were assessed by multilevel logistic regression analysis and Krippendorff alpha, respectively. Improvements in diagnostic performance were expressed as an odds ratio between the odds of improvement in OE compared with the odds of improvement in HD-WLE.

Results

Accuracy of neoplasia detection was significantly higher in all trainees who used OE versus HD-WLE (76% vs 63%) and in 6 experts (84% vs 77%). OE improved sensitivity of dysplasia detection compared with HD-WLE in 6 trainees (81% vs 71%) and 5 experts (77% vs 67%). Specificity improved in 6 trainees who used OE versus HD-WLE (70% vs 55%) and in 5 experts (92% vs 86%). PPV improved in both an expert and trainee cohort, but NPV improved significantly only in trainees. By using the MV classification and OE magnification endoscopy compared with HD-WLE, we demonstrated improvements in accuracy (79.9% vs 66.7%), sensitivity (86.3% vs 83.4%), and specificity (71.2% vs 53.6%) of dysplasia detection. PPV improved (62%-76.6%), as did NPV (67.7%-78.5%). Interobserver agreement also improved by using OE from 0.30 to 0.55.

Conclusion

iScan OE may improve dysplasia detection on endoscopic imaging of BE as well as the accuracy of histology prediction compared with HD-WLE, when OE magnification endoscopy is used in conjunction with a simple classification system by both expert and non-expert endoscopists.

中文翻译：

---

使用光学增强技术的虚拟色内窥镜检查可改善Barrett食道相关瘤形成的检测

背景和目标

内窥镜Barrett食道（BE）监视的Seattle协议对一小部分粘膜表面积进行采样，可能会导致早期肿瘤性病变的潜在高漏诊率。我们评估了新的iScan光学增强系统（OE）与专家和受训内窥镜医师中的高清白光内窥镜检查（HD-WLE）相比，是否可以改善早期BE相关肿瘤的检测，以针对可疑区域进行采样。这样的系统既可以改善早期肿瘤形成的检测，又可以减少对随机活检的需要。

方法

从2016年1月至2017年11月，共从41个国际转诊中心招募了41位接受内镜BE监测的患者。通过内窥镜检查获得了HD-WLE（n = 130）和iScan OE（n = 132）中匹配的静止图像。两位对视频和组织学不了解的专家描绘了已知的肿瘤，形成了共识标准。7名专家和7名受训内镜医师在每个图像上标记了1个位置，他们希望通过活检来识别发育不良的组织。然后，同一专家小组审查了放大图像，并使用先前验证的分类系统，根据在放大内窥镜上观察到的粘膜和血管（MV）模式，尝试将粘膜分类为增生或非增生。诊断准确性，灵敏度，特异性，计算阴性预测值（NPV）和阳性预测值（PPV）。通过多级逻辑回归分析和Krippendorff alpha评估了HD-WLE与OE和观察者之间的异型增生检测的改善。诊断性能的改善表示为OE改善几率与HD-WLE改善几率之间的几率比。

结果

在所有使用OE的学员中，与HD-WLE相比，赘生检测的准确性显着更高（76％比63％）和6位专家（84％比77％）。与HD-WLE相比，OE改善了6位受训者（81％对71％）和5位专家（77％对67％）的发育异常检测敏感性。使用OE与HD-WLE的6名受训者（70％比55％）和5名专家（92％对86％）的特异性得到了改善。PPV在专家和受训者队列中均得到改善，但NPV仅在受训者中得到了显着改善。通过使用MV分类和OE放大内窥镜检查与HD-WLE相比，我们发现异型增生检测的准确性（79.9％vs 66.7％），敏感性（86.3％vs 83.4％）和特异性（71.2％vs 53.6％）有所提高。PPV有所改善（62％-76.6％），NPV也有所改善（67.7％-78.5％）。通过将OE从0.30提高到0.55，观察者之间的协议也得到了改善。

结论

当OE放大内窥镜与专家和非专家内镜医师共同使用的简单分类系统结合使用时，与HD-WLE相比，iScan OE可能会改善BE内窥镜上的异型增生检测以及组织学预测的准确性。