Background and Aims

Right-sided lesions are often missed during standard colonoscopy (SC). A second forward-view examination or retroflexion in the right side of the colon have both been proposed as techniques to improve adenoma detection rate (ADR) in the right side of the colon. Comparative data on examining the right side of the colon with a second forward view or retroflexion is not known in a pooled analysis. We performed a systematic review of the literature to assess the yield of a second forward view compared with retroflexion examination for the detection of right-sided adenomas.

Methods

A systematic literature search was performed using the following databases: PubMed, Embase, Web of Science, and Cochrane. Only full-length published articles that provided information on adenoma detection and miss rates during either a second forward view or retroflexed view of the right side of the colon after the initial standard forward withdrawal (SC) were included. The following outcomes were assessed: comparison of adenoma miss rate (AMR) for second forward view versus retroflexion after SC, AMR of SC compared with second forward view, AMR of SC compared with retroflexion, and right-sided adenoma detection with second forward view and retroflexion. Pooled rates were reported as risk difference or odds ratios (OR) with 95% confidence intervals (CI) with a P value <.05 indicating statistical significance. Statistical analysis was performed with Review Manager v5.3.

Results

We identified 4 studies with 1882 patients who underwent a second forward view of the right side of the colon after an initial SC. The average age of the patients was 58.3 years. Data on right-sided ADR were available from all 4 studies for the second forward view; however, only 2 of the studies provided information on right-sided ADR with retroflexion. The pooled estimate of AMR of a single SC was 13.3% (95% CI, 6.6%-20%) compared with a second forward-view examination (n = 4), whereas it was 8.1% (3.7%-12.5%) compared with a retroflexion examination (n = 3). However, when the second forward view was compared with retroflexion in terms of AMR from an analysis of 3 eligible studies, there was no statistically significant difference (7.3% vs 6.3%; pooled OR, 1.2; 95% CI, 0.9-1.61; P = .21). Second forward view of the right side of the colon increased the right-sided ADR by 10% (n = 4; second forward view vs SC, 33.6% vs 26.7%) with a pooled risk difference of 0.09 (95% CI, 0.03-0.15; P < .01). Retroflexion increased the right-sided ADR by 6% (n = 3; retroflexion vs SC, 28.4% vs 22.7%) with a pooled risk difference of 0.06 (95% CI, 0.03-0.09; P < 01).

Conclusion

After SC withdrawal, a second forward view and retroflexed view of the right side of the colon are both associated with improvement in ADR. One of these techniques should be considered during SC to increase ADR and to improve the quality of colonoscopy.

中文翻译：

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与后屈与第二种前瞻性观点相比，结肠右侧腺瘤检出率提高：系统综述

背景和目标

在标准结肠镜检查（SC）期间经常会漏掉右侧病变。已经提出在结肠右侧进行第二次前视检查或后屈，作为提高结肠右侧腺瘤检出率（ADR）的技术。在合并分析中，尚无关于通过第二次前视或后屈检查检查结肠右侧的比较数据。我们对文献进行了系统的综述，以评估第二前视与后屈检查相比对右侧腺瘤的检出率。

方法

使用以下数据库进行了系统的文献检索：PubMed，Embase，Web of Science和Cochrane。仅收录了在标准正向撤回（SC）后第二次正视或右后视时提供有关腺瘤检出和漏诊率的信息的完整发表文章。评估了以下结果：比较第二前视图与SC后后屈的腺瘤缺失率（AMR），SC与第二前视图相比的AMR，SC与后屈相比的SC以及第二前视图与右后侧腺瘤的检测翻转。合并率报告为风险差异或比值比（OR），95％置信区间（CI），P值<.05表示具有统计意义。使用Review Manager v5.3进行统计分析。

结果

我们确定了4项针对1882例患者的研究，这些患者在初次SC术后对结肠的右侧进行了第二次正视。患者的平均年龄为58.3岁。可以从所有4项研究中获得右侧ADR的数据，作为第二种前瞻性观点；然而，只有2项研究提供了有关右后屈逆转ADR的信息。与第二次前瞻性检查（n = 4）相比，单个SC的AMR汇总估计值为13.3％（95％CI，6.6％-20％），而与之相比，则为8.1％（3.7％-12.5％）进行后屈检查（n = 3）。然而，当通过对3项合格研究的分析将第二种前瞻性观点与AMR方面的后屈进行比较时，没有统计学上的显着差异（7.3％vs 6.3％；合并OR为1.2； 95％CI为0.9-1.61；P = .21）。结肠右侧的第二个前视图使右侧ADR增加了10％（n = 4；第二个前视图与SC相比，分别为33.6％和26.7％），合并风险差异为0.09（95％CI，0.03-） 0.15；P  <0.01）。后屈使右侧ADR增加6％（n = 3；后屈vs. SC，分别为28.4％vs 22.7％），合并风险差为0.06（95％CI，0.03-0.09; P  <01）。

结论

撤回SC后，结肠右侧的第二个正视图和后弯视图都与ADR的改善有关。在SC期间应考虑这些技术之一，以增加ADR并改善结肠镜检查的质量。