Magnified and enhanced computed virtual chromoendoscopy in gastric neoplasia: A feasibility study

AIM: To evaluate the feasibility of a new computed virtual chromoendoscopy (CVC) device (M i-scan) in the diagnosis of gastric neoplasia. METHODS: Patients with superficial lesions no larger than 1.0 cm found during high definition endoscopy were included. Those with advanced or obviously protruded or depressed lesions, lesions larger than 1.0 cm and/or lesions which were not amenable to observation by zoom function were excluded. The endoscopist was required to give the real-time descriptions of surface pit patterns of the lesions, based on surface pattern classification of enhanced magnification endoscopy. According to previous reports, types Ⅰ-Ⅲ represent nonneoplastic lesions, and types Ⅳ-Ⅴ represent neoplastic lesions. Diagnosis with M i-scan and biopsy was performed before histopathological diagnosis. Magnified images of gastric lesions with and without enhancement were collected for further analysis. The diagnostic yield of real-time M i-scan and effects on magnification image quality by tone enhancement (TE), surface enhancement (SE) and color enhancement (CE) were calculated. The selected images were sent to another endoscopist. The endoscopist rated the image quality of each lesion at 3 levels. Ratings of image quality were based on visualization of pit pattern, vessel and demarcation line. RESULTS: One hundred and eighty-three patients were recruited. Five patients were excluded for advanced gastric lesions, 1 patient was excluded for poor preparation and 2 patients were excluded for superficial lesions larger than 1.0 cm; 132 patients were excluded for no lesions found by high definition endoscopy. In the end, 43 patients with 43 lesions were included. Histopathology revealed 10 inflammation, 14 atrophy, 10 metaplasia, 1 low grade dysplasia (LGD), 5 high grade dysplasia (HGD) and 3 cancers. For 7 lesions classified into type Ⅰ, histopathology revealed 6 atrophy and 1 metaplasia; for 10 lesions classified into type Ⅱ, histopathology revealed 2 inflammation, 7 atrophy and 1 metaplasia; for 10 lesions classified into type Ⅲ, histopathology revealed 1 inflammation, 8 metaplasia and 1 LGD; for 9 lesions classified into type Ⅳ, histopathology revealed 4 inflammation, 1 atrophy and 4 HGD; for 7 lesions classified into type Ⅴ, histopathology revealed 3 inflammation, 1 HGD and 3 cancers. A total of 172 still images, including 43 images by white light (MWL) and 129 images by M i-scan (43 with TE, 43 with SE and 43 with CE), were selected and sent to the endoscopist who did the analysis. General image quality of M i-scan with TE and SE was significantly better than that of MWL (TE, 4.55 ± 1.07; SE, 4.30 ± 1.02; MWL, 3.25 ± 0.99; P < 0.001). Visualization of pit pattern was significantly improved by M i-scan with SE (1.93 ± 0.25 vs 1.50 ± 0.50, P < 0.001). Microvessel visualization was significantly improved by M i-scan with TE (1.23 ± 0.78 vs 0.76 ± 0.73, P < 0.001). Demarcation line visualization was improved by M i-scan with both TE and SE (TE, 1.75 ± 0.52; SE, 1.56 ± 0.59; MWL, 0.98 ± 0.44; P < 0.001). M i-scan with CE did not show any significant improvements of image quality in general or in the 3 key parameters. Although M i-scan with TE and SE slightly increased the diagnostic yield of MWL, there was no significant difference (P > 0.1). CONCLUSION: Although digital enhancement improves the image quality of magnification endoscopy, its value in improving the diagnostic yield seems to be limited.

Accuracy of virtual chromoendoscopy in differentiating gastric antral vascular ectasia from portal hypertensive gastropathy:A proof of concept study

BACKGROUND Accurate detection of gastric antral vascular ectasia(GAVE)is critical for proper management of cirrhosis-related gastrointestinal bleeding.However,endoscopic diagnosis of GAVE can be challenging when GAVE overlaps with severe portal hypertensive gastropathy(PHG).AIM To determine the added diagnostic value of virtual chromoendoscopy to high definition white light for real-time endoscopic diagnosis of GAVE and PHG.METHODS We developed an I-scan virtual chromoendoscopy criteria for diagnosis of GAVE and PHG.We tested our criteria in a cross-sectional cohort of cirrhotic adults with GAVE and PHG when high-definition white light endoscopy(HDWLE)diagnosis was in doubt.We then compared the accuracy of I-scan vs HDWLE alone to histology.RESULTS Twenty-three patients were included in this study(65.2%Caucasians and 60.9%males).Chronic hepatitis C was the predominant cause of cirrhosis(43.5%)and seven adults(30.4%)had confirmed GAVE on histology.I-scan had higher sensitivity(100%vs 85.7%)and specificity(75%vs 62.5%)in diagnosing GAVE compared to HDWLE.This translates into a higher,albeit not statistically significant,accuracy of I-scan in detecting GAVE compared to HDWLE alone(82%vs 70%).I-scan was less likely to lead to an accurate diagnosis of GAVE in patients on dialysis(P<0.05)and in patients with elevated creatinine(P<0.05).Iscan had similar accuracy to HDWLE in detecting PHG.CONCLUSION This pilot work supports that virtual chromoendoscopy may obviate the need for biopsies when the presence of GAVE is in doubt.Larger studies are needed to assess the impact of virtual chromoendoscopy on success of endoscopic therapy for GAVE.

Virtual chromoendoscopy in small bowel capsule endoscopy: New light or a cast of shadow?

AIM: To evaluate whether virtual chromoendoscopy can improve the delineation of small bowel lesions previously detected by conventional white light small bowel capsule endoscopy(SBCE). METHODS: Retrospective single center study. One hundred lesions selected from forty-nine consecutive conventional white light SBCE(SBCE-WL) examinations were included. Lesions were reviewed at three Flexible Spectral Imaging Color Enhancement(FICE) settings and Blue Filter(BF) by two gastroenterologists with ex-perience in SBCE, blinded to each other's findings, whoranked the quality of delineation as better, equivalent or worse than conventional SBCE-WL. Inter-observer percentage of agreement was determined and analyzed with Fleiss Kappa(k) coefficient. Lesions selected for the study included angioectasias(n = 39), ulcers/ero-sions(n = 49) and villous edema/atrophy(n = 12). RESULTS: Overall, the delineation of lesions was im-proved in 77% of cases with FICE 1, 74% with FICE 2, 41% with FICE 3 and 39% with the BF, with a percent-age of agreement between investigators of 89%(k = 0.833), 85%(k = 0.764), 66%(k = 0.486) and 79%(k = 0.593), respectively. FICE 1 improved the delineation of 97.4% of angioectasias, 63.3% of ulcers/erosions and 66.7% of villous edema/atrophy with a percentage of agreement of 97.4%(k = 0.910), 81.6%(k = 0.714) and 91.7%(k = 0.815), respectively. FICE 2 improved the delineation of 97.4% of angioectasias, 57.1% of ulcers/erosions and 66.7% of villous edema/atrophy, with a percentage of agreement of 89.7%(k = 0.802), 79,6%(k = 0.703) and 91.7%(k = 0.815), respectively. FICE 3 improved the delineation of 46.2% of angioecta-sias, 24.5% of ulcers/erosions and none of the cases of villous edema/atrophy, with a percentage of agreement of 53.8% [k = not available(NA)], 75.5%(k = NA) and 66.7%(k = 0.304), respectively. The BF improved the delineation of 15.4% of angioectasias, 61.2% of ulcers/erosions and 25% of villous edema/atrophy, with a per-centage of agreement of 76.9%(k = 0.558), 81.6%(k = 0.570) and 25.0%(k = NA), respectively.CONCLUSION: Virtual chromoendoscopy can improve the delineation of angioectasias, ulcers/erosions and villous edema/atrophy detected by SBCE, with almost perfect interobserver agreement for FICE 1.

图像增强内窥镜在结直肠病变检测中的应用进展

图像增强内窥镜(IEE)是一种内窥镜成像技术,可用于改善胃肠道病变的黏膜表面形态和微血管系统特征的可视化,在实时诊断中起着至关重要的作用。使用不同的工具和技术可以进行实时光学诊断,例如窄带成像(NBI)、宾得内窥镜(i-SCAN)、柔性光谱成像色彩增强(FICE)、蓝色激光成像(BLI)和联动彩色成像(LCI)等。该文就IEE在结直肠病变检测中的应用进展进行综述,以期为临床检测结直肠病变提供新的理论依据。

Precision in detecting colon lesions:A key to effective screening policy but will it improve overall outcomes?

Colonoscopy is the gold standard for the screening and diagnosis of colorectal cancer,resulting in a decrease in the incidence and mortality of colon cancer.However,it has a 21%rate of missed polyps.Several strategies have been devised to increase polyp detection rates and improve their characterization and delimi-tation.These include chromoendoscopy(CE),the use of other devices such as Endo cuffs,and major advances in endoscopic equipment[high definition,magnification,narrow band imaging,i-scan,flexible spectral imaging color enhancement,texture and color enhancement imaging(TXI),etc.].In the retrospective study by Hiramatsu et al,they compared white-light imaging with CE,TXI,and CE+TXI to determine which of these strategies allows for better definition and delimitation of polyps.They concluded that employing CE associated with TXI stands out as the most effective method to utilize.It remains to be demonstrated whether these results are extrapolatable to other types of virtual CE.Additionally,further investigation is needed in order to ascertain whether this strategy could lead to a reduction in the recurrence of excised lesions and potentially lower the occurrence of interval cancer.

Validation of Fujinon intelligent chromoendoscopy with high definition endoscopes in colonoscopy

AIM:To validate high definition endoscopes with Fujinon intelligent chromoendoscopy(FICE) in colonoscopy.METHODS:The image quality of normal white light endoscopy(WLE),that of the 10 available FICE filters and that of a gold standard(0.2% indigo carmine dye) were compared.RESULTS:FICE-filter 4 [red,green,and blue(RGB) wavelengths of 520,500,and 405 nm,respectively] provided the best images for evaluating the vascular pattern compared to white light.The mucosal surface was best assessed using filter 4.However,the views obtained were not rated significantly better than those observed with white light.The "gold standard",indigo carmine(IC) dye,was found to be superior to both white light and filter 4.Filter 6(RGB wavelengths of 580,520,and 460 nm,respectively) allowed for exploration of the IC-stained mucosa.When assessing mucosal polyps,both FICE with magnification,and magnification following dye spraying were superior to the same techniques without magnification and to white light imaging.In the presence of suboptimal bowel preparation,observation with the FICE mode was possible,and endoscopists considered it to be superior to observation with white light.CONCLUSION:FICE-filter 4 with magnification improves the image quality of the colonic vascular patterns obtained with WLE.

虚拟色素内镜在小肠黏膜病损成像中的应用价值

目的评价虚拟色素内镜在小肠黏膜病损成像中的应用价值。方法采用单中心回顾性研究方法,将白光胶囊内镜获取的49例100处小肠病损图像,由两位内镜专家分别在FIC E1、FIC E2、FIC E3及BF 4种条件下重建病损图像,并与白光胶囊内镜获取图像进行比较。K appa系数评价两位专家判别结果的一致性。100处小肠病损包括39处血管病损、49处溃疡（糜烂）病损及12例处水肿（萎缩）病损。结果采用FIC E1、FIC E2、FIC E3和BF图像重建条件后,小肠黏膜病损图像质量提高率分别为77%（77/100）、74%（74/100）、41%（41/100）和39%（39/100）,两位专家之间评价一致性程度分别为89%[k=0.833（P〈0.001）,95%C I：0.741-0.925]、85%[k=0.764（P〈0.001）,95%C I：0.654-0.874]、66%[k=0.486（P〈0.001）,95%C I：0.345-0.627]及79%[k=0.593（P〈0.001）,95%C I：0.438-0.748]。结论在常规SBC E-W L对小肠病损成像与表征不直观情况下,可使用虚拟色素内镜检查（尤其是FIC E1）,可将虚拟色素内镜检查作为常规白光SBC E检查的补充,用以评估难以解读的内镜图像。

Efficacy of computed image modification of capsule endoscopy in patients with obscure gastrointestinal bleeding

AIM:To investigate whether flexible spectral color enhancement(FICE) improves diagnostic yields of capsule endoscopy(CE) for obscure gastro-intestinal bleeding(OGIB).METHODS:The study subjects consisted of 81 patients.Using FICE,there were three different sets with different wavelengths.Using randomly selected sets of FICE,images of CE were evaluated again by two individuals who were not shown the conventional CE reports and findings.The difference between FICE and conventional imaging was examined.RESULTS:The overall diagnostic yields in FICE sets 1,2,3 and conventional imaging(48.1%) were 51.9%,40.7%,51.9% and 48.1%,respectively,which showed no statistical difference compared to conventional imaging.The total numbers of detected lesions per examination in FICE imaging and conventional imaging were 2.5 ± 2.1 and 1.8 ± 1.7,respectively,which showed a significant difference(P = 0.01).CONCLUSION:The diagnostic yield for OGIB is not improved by FICE.However,FICE can detect significantly more small bowel lesions compared to conventional imaging.

Comparative effectiveness of i-SCAN^(TM) and high-definition white light characterizing small colonic polyps

AIM： To evaluate accuracy of in vivo diagnosis of ad- enomatous vs non-adenomatous polyps using/-SCAN digital chromoendoscopy compared with high-definition white light. METHODS： This is a single-center comparative effec- tiveness pilot study. Polyps （n = 103） from 75 average- risk adult outpatients undergoing screening or surveil- lance colonoscopy between December 1, 2010 and April 1, 2011 were evaluated by two participating en- doscopists in an academic outpatient endoscopy center. Polyps were evaluated both with high-definition white light and with/-SCAN to make an/n vivo prediction of adenomatous vs non-adenomatous pathology. We de- termined diagnostic characteristics of/-SCAN and high- definition white light, including sensitivity, specificity, and accuracy, with regards to identifying adenomatous vs non-adenomatous polyps. Histopathologic diagnosis was the gold standard comparison. RESULTS： One hundred and three small polyps, de- tected from forty-three patients, were included in the analysis. The average size of the polyps evaluated in the analysis was 3.7 mm （SD 1.3 mm, range 2 mm to 8 mm）. Formal histopathology revealed that 54/103 （52.4%） were adenomas, 26/103 （25.2%） were hyper- plastic, and 23/103 （22.3%） were other diagnoses in- clude ＂lymphoid aggregates＂, ＂non-specific colitis,＂ and ＂no pathologic diagnosis.＂ Overall, the combined accu- racy of endoscopists for predicting adenomas was iden- tical between/-SCAN （71.8%, 95%CI： 62.1%-80.3%） and high-definition white light （71.8%, 95%CI： 62.1%-80.3%）. However, the accuracy of each endosco- pist differed substantially, where endoscopist A demon- strated 63.0% overall accuracy （95%CI： 50.9%-74.0%） as compared with endoscopist B demonstrating 93.3% overall accuracy （95%CI： 77.9%-99.2%）, irrespective of imaging modality. Neither endoscopist demonstrated a significant learning effect with i-SCAN during the study. Though endoscopist A increased accuracy using/-SCAN from 59% （95%CI： 42.1%-74.4%） in the first half to 67.6% （95%CI： 49.5%-82.6%） in the second half, and endoscopist B decreased accuracy usingi-SCAN from 100% （95%CI： 80.5%-100.0%） in the first half to 84.6% （95%CI： 54.6%-98.1%） in the second half, nei- ther of these differences were statistically significant. CONCLUSION：i-SCAN and high-definition white light had similar efficacy predicting polyp histology. Endosco- pist training likely plays a critical role in diagnostic test characteristics and deserves further study.

New aspects of modern endoscopy

The prognosis for patients with malignancies of the ga-strointestinal-tract is strictly dependent on early detec-tion of premalignant and malignant lesions. However, small, flat or depressed neoplastic lesions remain dif-ficult to detect with these technologies thereby limiting their value for polyp and cancer screening. At the same time computer and chip technologies have undergone major technological changes which have greatly im-proved endoscopic diagnostic investigation. New imag-ing modalities and techniques are very notable aspects of modern endoscopy. Chromoendoscopy or filter-aided colonoscopy(virtual chromoendoscopy) with high defi-nition endoscopes is able to enhance the detection and characterization of lesions. Finally, confocal laser en-domicroscopy provides histological confirmation of the presence of neoplastic changes. The developing tech-niques around colonoscopy such as the retro-viewing colonoscope, the balloon-colonoscope or the 330-de-grees-viewing colonoscope try to enhance the efficacy by reducing the adenoma miss rate in right-sided, non-polypoid lesions. Colon capsule endoscopy is limited to identifying cancer and not necessarily small adenomas. Preliminary attempts have been made to introduce this technique in clinical routine.

PICaSSO组织学缓解指数在溃疡性结肠炎疾病评估中的价值

目的:探究PICaSSO组织学缓解指数(PHRI)在溃疡性结肠炎(UC)评估中的临床应用价值。方法:采用横断面研究方法,收集2018年6月至2019年10月北京协和医院消化内科确诊的UC患者的临床资料,包括人口学特点、蒙特利尔分型、血清学指标、Mayo总评分、Mayo内镜评分(MES)、溃疡性结肠炎内镜下严重程度指数(UCEIS)、Robarts组织病理学指数(RHI)评分和PHRI评分。采用Mayo总评分评估疾病的临床活动度。将MES=0分或UCEIS≤1分定义为内镜缓解(ER),将RHI≤3分或PHRI<1分定义为组织学缓解(HR)。采用Spearman相关性分析评估PHRI评分分别与血清学指标、内镜评分及RHI评分的相关性,采用Kappa检验分析评分间一致性。结果:共纳入60例UC患者,男性31例,女性29例;年龄(40.5±13.7)岁。其中病变位于直肠(E1)11例,左半结肠(E2)14例,广泛结肠(E3)35例。根据Mayo总评分,临床缓解20例,轻度活动20例,中度活动12例,重度活动8例。PHRI<1分15例,为PHRI-HR组;≥1分45例,为非HR组。Spearman相关性分析发现,PHRI评分与血清白蛋白水平呈负相关(r_(s)=-0.327,P=0.011);PHRI评分与MES、UCEIS评分之间呈强正相关(r_(s)=0.698、0.735,均P<0.001);PHRI评分与RHI评分呈极强正相关(r_(s)=0.868,P<0.001)。PHRI-HR组与非HR组白蛋白水平差异具有统计学意义(Z=-2.364,P=0.018)。Kappa一致性检验结果显示,MES-ER与PHRI-HR的结果中度一致(κ=0.535,P<0.001),其判断PHRI-HR的特异度为91.1%,准确度为83.3%;UCEIS-ER与PHRI-HR结果也为中度一致(κ=0.542,P<0.001),其判断PHRI-HR的特异度为90.5%,准确度为81.7%;RHI-HR与PHRI-HR的结果一致性较强(κ=0.644,P<0.001),其判断PHRI-HR的特异度为73.3%,准确度为86.7%。结论:PHRI与RHI和内镜评分密切相关,是具有潜力的评价UC疾病活动度的组织病理学评分。