Pode o Blue Laser Imaging colaborar no diagnóstico diferencial entre lesões neoplásicas e não neoplásicas colorretais? / Can Blue Laser Imaging collaborate in the differential diagnosis between neoplastic and non-neoplastic colorectal lesions?

Introdução: Imagem endoscópica aprimorada permite o diagnóstico diferencial das lesões colorretais em tempo real através do estudo da microvasculatura. Objetivo: Revisar o uso do Blue Laser Imaging (BLI) na análise do padrão dos capilares para o diagnóstico diferencial entre lesões neoplásicas e não neoplásicas. Métodos: Esta é revisão integrativa da literatura que colheu informações publicadas em plataformas virtuais em português e inglês. A busca para leitura e análise foi realizada nas plataformas SciELO ­ Scientific Electronic Library Online, Google Scholar, Pubmed e Scopus. Os descritores retirados do DeCS/MESH foram: "Blue laser imaging. Endoscopia. Cromoendoscopia, Pólipos colorretais. Magnificação" e seus correspondentes em inglês "Blue laser imaging. Image-enhanced endoscopy. Chromoendoscopy. Colorectal polyps. Magnification" com busca AND ou OR, considerando o título e/ou resumo. Foram incluídos somente os que tivessem maior correlação ao tema, e neles foi baseada a revisão com leitura, na íntegra, dos textos. Resultados: Ao final resultaram 22 artigos que compuseram esta revisão. Conclusão: BLI associada à magnificação mostrou bons resultados no diagnóstico histológico preditivo em tempo real para as lesões de cólon e reto.

Introduction: Improved endoscopic imaging allows the differential diagnosis of colorectal lesions in real time through the study of the microvasculature. Objective: To review the use of Blue Laser Imaging (BLI) in analyzing the capillary patern for the differential diagnosis between neoplastic and nonneoplastic lesions. Methods: This is an integrative review of the literature that collected information published on virtual platforms in Portuguese and English. The search for reading and analysis was carried out on the SciELO ­ Scientific Electronic Library Online, Google Scholar, Pubmed and Scopus platforms. The descriptors taken from DeCS/MESH were: "Blue laser imaging. Endoscopy. Chromoendoscopy, Colorectal polyps. Magnification" and its English counterparts "Blue laser imaging. Image-enhanced endoscopy. Chromoendoscopy. Colorectal polyps. Magnification" with AND or OR search, considering the title and/or abstract. Only those that had the greatest correlation to the topic were included, and the review was based on them, with reading, in full, of the texts. Results: In the end, 22 articles resulted that made up this review. Conclusion: BLI associated with magnification showed good results in real-time predictive histological diagnosis for colon and rectal lesions.

Comparison of the ability of two artificial intelligence systems based on different training methods to diagnose early gastric cancer under magnifying image-enhanced endoscopy / 中华消化杂志

Objective:To compare the ability of deep convolutional neural network-crop (DCNN-C) and deep convolutional neural network-whole (DCNN-W), 2 artificial intelligence systems based on different training methods to dignose early gastric cancer (EGC) diagnosis under magnifying image-enhanced endoscopy (M-IEE).Methods:The images and video clips of EGC and non-cancerous lesions under M-IEE under narrow band imaging or blue laser imaging mode were retrospectively collected in the Endoscopy Center of Renmin Hospital of Wuhan University, for the training set and test set for DCNN-C and DCNN-W. The ability of DCNN-C and DCNN-W in EGC identity in image test set were compared. The ability of DCNN-C, DCNN-W and 3 senior endoscopists (average performance) in EGC identity in video test set were also compared. Paired Chi-squared test and Chi-squared test were used for statistical analysis. Inter-observer agreement was expressed as Cohen′s Kappa statistical coefficient (Kappa value).Results:In the image test set, the accuracy, sensitivity, specificity and positive predictive value of DCNN-C in EGC diagnosis were 94.97%(1 133/1 193), 97.12% (202/208), 94.52% (931/985), and 78.91%(202/256), respectively, which were higher than those of DCNN-W(86.84%, 1 036/1 193; 92.79%, 193/208; 85.58%, 843/985 and 57.61%, 193/335), and the differences were statistically significant ( χ2=4.82, 4.63, 61.04 and 29.69, P=0.028, =0.035, <0.001 and <0.001). In the video test set, the accuracy, specificity and positive predictive value of senior endoscopists in EGC diagnosis were 67.67%, 60.42%, and 53.37%, respectively, which were lower than those of DCNN-C (93.00%, 92.19% and 87.18%), and the differences were statistically significant ( χ2=20.83, 16.41 and 11.61, P<0.001, <0.001 and =0.001). The accuracy, specificity and positive predictive value of DCNN-C in EGC diagnosis were higher than those of DCNN-W (79.00%, 70.31% and 64.15%, respectively), and the differences were statistically significant ( χ2=7.04, 8.45 and 6.18, P=0.007, 0.003 and 0.013). There were no significant differences in accuracy, specificity and positive predictive value between senior endoscopists and DCNN-W in EGC diagnosis (all P>0.05). The sensitivity of senior endoscopists, DCNN-W and DCNN-C in EGC diagnosis were 80.56%, 94.44%, and 94.44%, respectively, and the differences were not statistically significant (all P>0.05). The results of the agreement analysis showed that the agreement between senior endoscopists and the gold standard was fair to moderate (Kappa=0.259, 0.532, 0.329), the agreement between DCNN-W and the gold standard was moderate (Kappa=0.587), and the agreement between DCNN-C and the gold standard was very high (Kappa=0.851). Conclusion:When the training set is the same, the ability of DCNN-C in EGC diagnosis is better than that of DCNN-W and senior endoscopists, and the diagnostic level of DCNN-W is equivalent to that of senior endoscopists.

New Diagnostic Approach for Esophageal Squamous Cell Neoplasms Using Linked Color Imaging and Blue Laser Imaging Combined with Iodine Staining

A 62-year-old man with a flat early esophageal cancer was referred for endoscopic treatment. White light imaging revealed a pale red lesion, whereas linked color imaging (LCI) and blue laser imaging (BLI) yielded purple and brown images, respectively. Iodine staining demonstrated a large unstained area with a homogenous but very weak pink-color sign. This area appeared more clearly as purple and green on LCI and BLI, respectively; however, a different colored portion was observed at the 4 o'clock position inside the iodine-unstained area. Histopathology findings of the resected specimen revealed squamous intraepithelial neoplasia at the 4 o'clock position and an esophageal squamous cell carcinoma in the remaining iodine-unstained area. LCI and BLI combined with iodine staining produce characteristic images that overcomes the pink-color sign, reflecting the histological features of a flat esophageal neoplasm. This new method is useful for detailed evaluation of early flat squamous cell neoplasms.

The Past, Present, and Future of Image-Enhanced Endoscopy

Despite the remarkable progress recently made to enhance the resolution of white-light endoscopy, detection, and diagnosis of premalignant lesions, such as adenomas and subtle early-stage cancers, remains a great challenge. As for example, although chromoendoscopy, such as endoscopy using indigo carmine, is useful for the early diagnosis of subtle lesions, the technique presents various disadvantages ranging from the time required for spray application of the dye and suctioning of excess dye to the increased difficulty in identifying lesions in the presence of severe inflammation and obstruction of visual field due to the pooling of solution in depressed-type lesions. To overcome these diagnostic problems associated with chromoendoscopy, research has focused on the development of endoscopes based on new optical technologies. Several types of image-enhanced endoscopy methods have recently been presented. In particular, image-enhanced endoscopy has emerged as a new paradigm for the diagnosis of gastrointestinal disorders. Image-enhanced endoscopes provide high-contrast images of lesions by means of optical or electronic technologies, including the contrast enhancement of the mucosal surface and of blood vessels. Chromoendoscopy, narrow-band imaging, i-SCAN, and flexible spectral imaging color enhancement are representative examples of image-enhanced endoscopy discussed in this paper.

Narrow Band Imaging: Technology Basis and Research and Development History

The first launch of narrow band imaging (NBI) was in 2005. Since then, in most countries where gastrointestinal endoscopies are performed, NBI is the most commonly used optical digital method of performing image-enhanced endoscopy. Thanks to the outstanding efforts of many endoscopists, many clinical studies have been performed and clinical evidence has been gathered. In Japan, since 2010, NBI has been reimbursed under the Japanese national health insurance system. This is owing to the establishment of clinical evidence by physicians. However, even though endoscope systems with NBI function have been widely used outside of Japan, dissemination of knowledge on how to use NBI is insufficient. In this review paper, the technology basis of NBI and its research and development history are described. I hope this information will be helpful for updating physicians' knowledge of NBI.

Advanced Imaging Technology in Biliary Tract Diseases:Narrow-Band Imaging of the Bile Duct

Newly introduced direct peroral cholangioscopy and the development of video choledochoscopes have enabled more defined observation of bile duct mucosal lesions with clearer images. Narrow-band imaging (NBI) is a unique endoscopic imaging technology that provides enhanced endoscopic images of surface mucosal structures and its superficial microvessels. Advanced cholangioscopy and NBI are expected to be useful for precise evaluation and correct diagnosis of biliary tract diseases. However, the diagnostic value of advanced bile duct imaging with cholangioscopy requires further evaluation.

Advanced Imaging Technology Other than Narrow Band Imaging

To improve the detection rate of gastrointestinal tumors, image-enhanced endoscopy has been widely used during screening and surveillance endoscopy in Korea. In addition to narrow band imaging (NBI) with/without magnification, various types of electronic chromoendoscopies have been used, including autofluorescence imaging, I-scan, and flexible spectral imaging color enhancement. These technologies enable the accurate characterization of tumors because they enable visualization of microvascular and microsurface patterns. The present review focuses on understanding the principle and clinical applications of advanced imaging technologies other than NBI.

Is Image-Enhanced Endoscopy Useful for the Diagnosis and Treatment of Gastrointestinal Tumor?

Since the introduction of endoscopic submucosal dissection method for the treatment of early gastric cancer, endoscopic treatment of early gastric cancer has increased exponentially. Accordingly, early diagnosis of cancerous or precancerous lesion has become one of the most important missions for endoscopists. The desire to improve diagnostic capability of white light endoscopy led to the development of new imaging techniques called "image enhanced endoscopy." The usefulness of these image enhanced endoscopy has not been proven yet, although there are several studies reporting diagnostic superiority of these new imaging methods over white light endoscopy. Among these new imaging modalities, narrow band image (NBI) with magnification endoscopy has been most widely used and studied. This manuscript will be focused on the NBI with magnification endoscopy.

Role of Enhanced Visibility in Evaluating Polyposis Syndromes Using a Newly Developed Contrast Image Capsule Endoscope

BACKGROUND/AIMS: A flexible spectral imaging color enhancement system was installed in new capsule software for video capsule endoscopy. Contrast image capsule endoscopy (CICE) is a novel technology using light-emitting diodes selected for the main absorption range of hemoglobin. We assessed the feasibility and diagnostic effi cacy for small bowel surveillance in patients with polyposis syndromes. METHODS: Six patients with polyposis syndromes, four with familial adenomatous polyposis and one each with Cowden syndrome (CS) and Cronkhite-Canada syndrome (CCS) were examined using CICE. We conducted three evaluations to assess the effect on the numbers of the detected polyps; compare polyp diagnostic rates between adenoma and hamartoma; and assess polyp visibility. RESULTS: The numbers of detected polyps and diagnostic accuracy did not differ signifi cantly between pre-contrast and contrast images. However, 50% of the adenomatous polyps displayed enhanced visibility on contrast images. CICE contrast images exhibited clearly demarcated lesions and improved the visibility of minute structures of adenomatous polyps. Hamartomatous polyp micro-structures in patients with CS and CCS were more clearly visualized on contrast than pre-contrast images. CONCLUSIONS: CICE is an effective tool for enhancing the visibility of polyps in patients with polyposis syndrome.