Conventional White Light Endoscopy Research Articles

Advantage of magnifying narrow-band imaging for the diagnosis of colorectal neoplasia associated with sessile serrated lesions.

This study aimed to extract endoscopic findings for diagnosing colorectal neoplasia associated with sessile serrated lesions (SSLs), which are of significant interest. To compare the magnifying narrow-band imaging (NBI) findings with microscopic morphology, we classified SSLs into two groups: Group A SSLs included the majority of uniform SSLs and any dysplasia other than that classified as group B SSLs. Group B SSLs included SSLs with intramucosal and invasive carcinoma. We also quantitatively assessed visible vessels using ImageJ software. This study included 47 patients with 50 group B SSLs who underwent endoscopic resection between 2012 and 2020. The results were retrospectively compared with those of 237 patients with 311 group A SSLs that underwent endoscopic resection. Using conventional white-light endoscopy, significantly more group B SSLs had uneven shapes and some reddening compared to group A SSLs. The diagnostic odds ratios for group B SSLs were as follows: lesions with a diameter ≥10 mm, 9.76; uneven shape, 3.79; reddening, 15.46; and visible vessels with NBI, 11.32. Regarding visible vessels with NBI, the specificity and diagnostic accuracy for group B SSLs were 94.9% and 93.1%, respectively. The percentage of the vascular tonal area of NBI images was significantly larger for group B SSLs than for group A SSLs (3.97% vs. 0.29%; p < 0.01). SSLs with reddening and/or a diameter ≥10 mm are suspected to contain cancerous components. Moreover, visible vessels observed using magnifying NBI can serve as objective indicators for diagnosing SSLs with cancerous components with a high degree of accuracy.

Application of narrow band imaging and Lugol's iodine staining in screening for nasopharyngeal carcinoma

BackgroundTo investigate the diagnostic value of conventional white light endoscopy (WLE), narrow band imaging (NBI) endoscopy, and Lugol's iodine staining under WLE (endoscopic iodine staining) in the screening and early diagnosis of nasopharyngeal carcinoma.MethodsPatients with nasopharyngeal lesions requiring biopsy attending the Department of Otolaryngology Head and Neck Surgery in our hospital between January 2021 and April 2023 were included in this study. Before biopsy, all subjects underwent conventional WLE, NBI endoscopy, and endoscopic iodine staining. On WLE, according to nasopharyngeal lesion morphology and color, patients were diagnosed with nasopharyngeal carcinoma ( +) or chronic hyperplastic nasopharyngitis (-). On NBI endoscopy, according to nasopharyngeal lesion vascular morphology, patients with type V manifestations (nasopharyngeal carcinoma) were categorized as NBI ( +) and patients with type I-IV manifestations (chronic hyperplastic nasopharyngitis) were categorized as NBI (-). Endoscopic iodine staining (1.6% Lugol's iodine solution) was positive ( +) if the mucosal surface was brown with no white patches, or negative (-) if there was no or light brown staining of the mucosal surface. Patients were divided into 2 groups based on histopathological diagnosis: nasopharyngeal carcinoma or chronic hyperplastic nasopharyngitis. Endoscopic diagnoses were compared with histopathological findings. The diagnostic performance of WLE, NBI endoscopy and endoscopic iodine staining for nasopharyngeal carcinoma were determined.ResultsThis study included 159 patients. On histopathology, 29 patients were diagnosed with nasopharyngeal carcinoma, and 130 patients were diagnosed with chronic hyperplastic nasopharyngitis. There were no significant differences in the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the receiver operating characteristic (ROC) curve (AUC) of conventional WLE, NBI endoscopy or endoscopic iodine staining for differentiating nasopharyngeal carcinoma and chronic hyperplastic nasopharyngitis. The diagnostic performance of the combination of conventional WLE, NBI endoscopy and endoscopic iodine staining was significantly improved compared to any procedure alone.ConclusionsConventional WLE, NBI endoscopy or endoscopic iodine staining had good diagnostic performance for differentiating nasopharyngeal carcinoma and chronic hyperplastic nasopharyngitis. In particular, NBI endoscopy and endoscopic iodine staining alone or combined had clinical utility for identifying patients with nasopharyngeal lesions that are eligible for a watch-and-wait strategy.

Wide-field endoscope accessory for multiplexed fluorescence imaging

A wide-field endoscope that is sensitive to fluorescence can be used as an adjunct to conventional white light endoscopy by detecting multiple molecular targets concurrently. We aim to demonstrate a flexible fiber-coupled accessory that can pass forward through the instrument channel of standard medical endoscopes for clinical use to collect fluorescence images. A miniature scan mirror with reflector dimensions of 1.30 × 0.45 mm2 was designed, fabricated, and placed distal to collimated excitation beams at λex = 488, 660, and 785 nm. The mirror was driven at resonance for wide angular deflections in the X and Y-axes. A large image field-of-view (FOV) was generated in real time. The optomechanical components were packaged in a rigid distal tip with dimensions of 2.6 mm diameter and 12 mm length. The scan mirror was driven at 27.6 and 9.04 kHz in the fast (X) and slow (Y) axes, respectively, using a square wave with 50% duty cycle at 60 Vpp to collect fluorescence images at 10 frames per sec. Maximum total divergence angles of ± 27.4° and ± 22.8° were generated to achieve a FOV of 10.4 and 8.4 mm, respectively, at a working distance of 10 mm. Multiplexed fluorescence images were collected in vivo from the rectum of live mice using 3 fluorescently-labeled peptides that bind to unique cell surface targets. The fluorescence images collected were separated into 3 channels. Target-to-background ratios of 2.6, 3.1, and 3.9 were measured. This instrument demonstrates potential for broad clinical use to detect heterogeneous diseases in hollow organs.

DESIGN AND ANALYSIS OF IODINE STAINING AND NBI IN THE DIAGNOSTIC MODEL AND DIAGNOSIS OF EARLY ESOPHAGEAL CANCER AND ITS PRECANCEROUS LESIONS

Objective: This study aimed to compare the differences between narrowband imaging (NBI) and Lugo’s iodine staining endoscopy (LCE) for detecting and elucidating the site, clarity, and diagnostic accuracy of early esophageal cancer and precancerous lesions. Methods: We included patients with a high risk of developing esophageal cancer who visited the Zhongjiang County People’s Hospital between October 2020 and October 2022. Endoscopic examination was performed on each study participant. White-light endoscopy was used to observe and locate the diseased mucosa, after which NBI mode and LCE staining were used to observe the boundary between the diseased and normal mucosa. Abnormal lesions were found, and biopsies were performed on the identifiable diseased parts for pathological examination. Inflammation, LGIN, HGIN, and early esophageal cancer were diagnosed, and the differences between them were compared in terms of the two enhanced-image endoscopy techniques. A semantic segmentation model based on deep learning was adopted to assist in the diagnosis of early esophageal cancer and accurately locate cancerous areas. In order to improve its accurate diagnostic rate, we also built a semantic segmentation network model to assist in the computer-aided diagnosis of early esophageal cancer. Results: A total of 69 cases of early esophageal cancer were included in this study. The patients were aged 40–75 years, with an average age of [Formula: see text] years. Most early esophageal cancer lesions were located in the middle of the esophagus in 45/69 (65.2%) cases. LCE obtained higher clarity of lesion boundaries than NBI (59.4% versus 45.0% and 27.7% versus 15.9%, respectively), and the proportion of unclear lesions was lower (8.6% versus 21.7% and 4.3% versus 17.4%, respectively; [Formula: see text]). For early esophageal cancer and precancerous lesions, the missed-diagnosis rate of white-light endoscopy was 20%, that of NBI was 3.15%, and that of LCE was 0%, with statistical significance ([Formula: see text]). The rate of missed diagnosis of LGIN (three cases) by NBI was 3.15%, which was not significantly different from that of LCE ([Formula: see text]). We found that the lesion area could be more accurately determined using deep learning models to segment NBI images. By constructing a deep learning model for the diagnosis and classification of esophageal cancer, its diagnostic rate rose to 99.5%. Conclusion: The age range of patients with early esophageal cancer in Zhongjiang County, Sichuan Province, was 40–75 years, and tumors mostly occurred in the middle of the esophagus. The boundary clarity of early esophageal carcinomas was higher on LCE than that on NBI. The diagnostic accuracies of NBI and LCE are much higher than those of conventional white-light endoscopy. Therefore, both LCE and NBI are helpful for detecting early esophageal cancer and precancerous lesions. Moreover, the diagnostic rate of clinical esophageal cancer can be effectively improved using a dedicated deep learning network model.

Phthalocyanine-Blue Nanoparticles for the Direct Visualization of Tumors with White Light Illumination.

The current standard of care for colon cancer surveillance relies heavily on white light endoscopy (WLE). However, dysplastic lesions that are not visible to the naked eye are often missed when conventional WLE equipment is used. Although dye-based chromoendoscopy shows promise, current dyes cannot delineate tumor tissues from surrounding healthy tissues accurately. The goal of the present study was to screen various phthalocyanine (PC) dye-loaded micelles for their ability to improve the direct visualization of tumor tissues under white light following intravenous administration. Zinc PC (tetra-tert-butyl)-loaded micelles were identified as the optimal formulation. Their accumulation within syngeneic breast tumors led the tumors to turn dark blue in color, making them clearly visible to the naked eye. These micelles were similarly able to turn spontaneous colorectal adenomas in Apc+/Min mice a dark blue color for easy identification and could enable clinicians to more effectively detect and remove colonic polyps.

Usefulness of texture and color enhancement imaging (TXI) in early gastric cancer found after Helicobacter pylori eradication

Early-stage gastric cancer (EGC) found after Helicobacter pylori (Hp) eradication is often difficult to diagnose using conventional white light (WL) endoscopy. We aimed to evaluate whether Texture and Color Enhancement Imaging (TXI), a new image-enhanced endoscopy enhances the EGC lesions after Hp eradication. We also compared diagnostic accuracy and lesion detection time between WL and TXI in trainee endoscopists. 58 EGC lesions after successful Hp eradication were enrolled. Using endoscopic images in WLI, TXI mode 1 (TXI1), and TXI mode 2 (TXI2), visibility of EGC was assessed by six expert endoscopists using a subjective score. Mean color differences (ΔE) of four matched adjacent and intra-tumoral points were examined. Using randomly allocated images, diagnostic accuracy and lesion detection time were evaluated in three trainee endoscopists. Visibility score was unchanged (Score 0) in 20.7% (12/58) and 45.6% (26/57), slightly improved (Score 1) in 60.3% (35/58) and 52.6% (30/57), obviously improved (Score 2) in 45.6% (26/58) and 1.8% (1/57), in TXI1 and TXI2 compared to WL, respectively. Mean ΔE ± SEM in TXI1 (22.90 ± 0.96), and TXI2 (15.32 ± 0.71) were higher than that in WL (1.88 ± 0.26, both P < 0.0001). TXI1 presented higher diagnostic accuracy compared to WL, in two of three trainees (94.8% vs. 74.1%, 100% vs. 89.7%, P = 0.003; < 0.005, respectively). Lesion detection time was shorter in TXI1 in two of three trainees (P = 0.006, 0.004, respectively) compared to WL. TXI improves visibility of EGC after Hp eradication that may contribute to correct diagnosis.

Development of artificial intelligence for the detection and staging of esophageal cancer

: Computer-assisted diagnosis (CAD) using deep learning, based on convolutional neural networks (CNNs), is rapidly developing in modern society and clinical practice. In the medical field of endoscopy, a CAD system can be used in the detection and staging of superficial esophageal cancer. In the detection of superficial esophageal squamous cell carcinoma (ESCC), several studies were reported as using still images of conventional white-light endoscopy and narrow-band imaging (NBI). The sensitivity of CAD systems is over 90%, and in some reports, higher than that of expert endoscopists. In addition, there is a report using video for a validation set that showed good performance. In diagnosing invasion depth, there are reports using conventional white-light imaging, NBI, and magnifying endoscopy with NBI using still images; there are also reports of intrapapillary capillary loop pattern identification using still images. Using white-light endoscopy and NBI, CAD systems showed sensitivity of 84.1–95.4%, specificity of 73.3–79.2%, and accuracy of 80.9–92.9% for differentiating SM1 cancers from SM2 or SM3 cancers in pathology. Additional systems could accurately classify intrapapillary capillary loop patterns as normal or abnormal, with comparable performance to experienced endoscopists. As for esophageal adenocarcinoma (EAC) that arises in Barrett’s esophagus (BE), there are detection reports that show favorable performance. Furthermore, the CAD system from one report identified the location suitable for biopsy; this is helpful for endoscopists because of the difficulty in determining the location of early EAC in BE. Although these studies are still only at research level, excellent performance has been achieved for detecting and staging of superficial esophageal carcinoma by CAD systems. In the near future, CAD systems will support us in detecting and staging esophageal cancers in daily clinical practice, leading to a better prognosis.

Colonic Anisakiasis

A 75-year-old man with hypertension, who was otherwise healthy, underwent a surveillance colonoscopy 1 year after a polypectomy. He had no specific symptoms, and his vital signs were normal. The examination showed an Anisakis larva invading the mucosa of the proximal ascending colon, where a semilunar fold was edematous and thickened with a small erosion on the inserted site (Figure A). Magnifying endoscopy with narrow-band imaging revealed a small whitish elongated spot (the ventricle, an organ located between the esophagus and the intestine of Anisakis larva), which was more clearly visible than with conventional white-light endoscopy (Figure B).

Narrow band endoscopic diagnosis of portal hypertensive gastropathy in cirrhotic patients

ABSTRACT Background Portal hypertensive gastropathy (PHG) is an overlooked complication of liver cirrhosis, as it is a source of acute upper gastrointestinal bleeding and cause of chronic blood loss. Objective To assess the role of narrow band endoscopy in the diagnosis of PHG in cirrhotic patients. Methods Fifty patients with liver cirrhosis were examined by both conventional White Light Endoscopy (WLE) and Narrow Band Technology Variable Intelligent Staining Technology (VIST) using Sonoscape endoscope HD500. Biopsies were taken from the body of gastric mucosa during endoscopy. Results The prevalence of PHG among patients with liver cirrhosis is around 94% by WLE, 92% by VIST, and 55.3% by pathology. There is no statistical significance between VIST and WLE in case of PHG p = 0,750. The risk of developing oesophageal varices grade 3 in severe PHG is higher than in no or mild PHG (OR = 6.8571, 95% CI 1.6270 to 28.9001, p = 0.0087). Conclusion VIST is comparable and complementary to WLE in diagnosis of PHG. There is poor correlation between pathology and WLE in diagnosis of PHG.

Image-enhanced endoscopy for real-time differentiation between hyperplastic and fundic gland polyps in the stomach.

Fundic gland polyps (FGP) of stomach are benign, while some hyperplastic polyps (HP) may harbor dysplasia or malignancy. Conventional white light endoscopy (WLE) cannot reliably distinguish FGP from HP. We investigated the role of image-enhanced endoscopy in differentiating FGP from HP. Patients with gastric polyps were recruited prospectively. The characteristics of the polyps were assessed using WLE and magnification narrow band imaging (mNBI). The microsurface, intervening space (IS), and microvascular (V) features of polyps were evaluated on mNBI. The pattern characteristic of FGP and HP were determined. Histopathology of polyps was the gold standard for diagnosis. Finally, in the validation phase, five endoscopists applied the characteristic features identified in this study to predict the type of gastric polyp and their performance was assessed. Forty-five patients with a total of 70 gastric polyps (HP-46, FGP-24) were included in this study. On mNBI, the pattern characteristic of HP included peripheral curved type of white structures forming large circular/villous loops (microsurface), enlarged intervening space, and microvessels appearing as dark patches in the intervening space (p<0.001 vs. FGP). These were noted in 95.7% HP. In contrast, 95.8% FGP had a pattern characterized by dotted/elliptical/tubular white structures (microsurface), normal width of intervening space, and microvessels surrounding the white structures in a network pattern. This IS-V pattern classification had an accuracy of >90% in the validation phase with intra-class correlation coefficient of 0.95. The accuracy of mNBI was higher than WLE (97.1% vs. 67%) in predicting the type of gastric polyp. Image-enhanced endoscopy with mNBI (IS-V pattern) performs very well in differentiating HP from FGP.

A case of early gastric cancer in a patient with gastric juvenile polyposis diagnosed by magnifying endoscopy and resected by endoscopic submucosal dissection

Gastric juvenile polyposis (GJP) is frequently associated with the development of gastric cancer. However, there are no reports of gastric cancer in patients with GJP diagnosed using magnifying endoscopy with narrow-band imaging (M-NBI) and successfully treated by endoscopic submucosal dissection (ESD). A 50-year-old woman was referred to our hospital. Conventional white-light endoscopy revealed numerous aggregated polyps with reddish and whitish areas in the gastric cardia. M-NBI revealed a regular microvascular pattern (MVP) and regular microsurface pattern (MSP) in the reddish area of the lesion, and they were diagnosed as non-cancerous polyps. There was a clear demarcation line between the reddish and whitish areas, with irregular MVP plus irregular MSP in the whitish area, which was diagnosed as early gastric cancer. The horizontal extent of the cancer was precisely identified using M-NBI, and the en bloc resection of cancerous lesions was performed using ESD. Histopathological examination of the resected specimen showed that the reddish area comprised a hyperplastic foveolar epithelium. Conversely, the whitish area was diagnosed as a well-differentiated adenocarcinoma. The cancer was limited to the mucosa, lymphovascular invasion was negative, and horizontal and vertical margins were free from cancerous tissue. According to surveillance endoscopy, there has been no recurrence 11years after ESD. This is the first report demonstrating that M-NBI is useful for making a precise diagnosis of cancer in juvenile polyposis and that ESD can be an option for the treatment of such a cancer.

A novel AI device for real-time optical characterization of colorectal polyps

Accurate in-vivo optical characterization of colorectal polyps is key to select the optimal treatment regimen during colonoscopy. However, reported accuracies vary widely among endoscopists. We developed a novel intelligent medical device able to seamlessly operate in real-time using conventional white light (WL) endoscopy video stream without virtual chromoendoscopy (blue light, BL). In this work, we evaluated the standalone performance of this computer-aided diagnosis device (CADx) on a prospectively acquired dataset of unaltered colonoscopy videos. An international group of endoscopists performed optical characterization of each polyp acquired in a prospective study, blinded to both histology and CADx result, by means of an online platform enabling careful video assessment. Colorectal polyps were categorized by reviewers, subdivided into 10 experts and 11 non-experts endoscopists, and by the CADx as either “adenoma” or “non-adenoma”. A total of 513 polyps from 165 patients were assessed. CADx accuracy in WL was found comparable to the accuracy of expert endoscopists (CADxWL/Exp; OR 1.211 [0.766–1.915]) using histopathology as the reference standard. Moreover, CADx accuracy in WL was found superior to the accuracy of non-expert endoscopists (CADxWL/NonExp; OR 1.875 [1.191–2.953]), and CADx accuracy in BL was found comparable to it (CADxBL/CADxWL; OR 0.886 [0.612–1.282]). The proposed intelligent device shows the potential to support non-expert endoscopists in systematically reaching the performances of expert endoscopists in optical characterization.

The classification of gastric antral vascular ectasia in cirrhotic patients by Versatile Intelligent Staining Technology

BackgroundPortal hypertensive gastropathy (PHG) and gastric antral vascular ectasia (GAVE) are two different pathologies that cause bleeding in cirrhotic patients. These two pathologies are still difficult to be distinguished by white light endoscopy (conventional), as they both appear as red spots in the gastric antral mucosa in the case of severe PHG. The aim of our study was to assess the efficacy of Versatile Intelligent Staining Technology (VIST) in comparison to histopathology in the diagnosis and classification of GAVE.MethodsA cross-sectional study included 50 patients with liver cirrhosis recruited from Alexandria Main University Hospital. Patients with connective tissue diseases and chronic kidney disease were excluded. All patients were examined by both conventional white light endoscopy (WLE) and image enhancement technology (VIST) using Sonoscape HD500 endoscope. GAVE was diagnosed as tortuous columns of ectatic vessels in the gastric antrum. Histopathological examination was used as the standard tool for the diagnosis of GAVE.ResultsA total of 50 patients were included, 28 patients (56 %) were diagnosed as GAVE by pathology vs 22 (44 %) as non-GAVE. Twenty-three of 28 (78.6 %) cases of GAVE were detected by VIST. VIST had superior sensitivity than WLE in the detection of GAVE, 82.1 % vs 7.1 %, while WLE had higher specificity 95.5 % vs 59.1 % by VIST. There was statistical significance between VIST and pathology in the diagnosis of GAVE, p<0.035, but no statistical significance between WLE and pathology. VIST has identified two types of GAVE: focal in 12/28 cases and diffuse in 11/28, and five were not diagnosed by VIST.ConclusionsVersatile Intelligent Staining Technology could be used as an alternative tool to histopathological diagnosis of GAVE. GAVE can present as a focal group of ectatic vessels which adds a new class to GAVE classification that was previously misdiagnosed.

Usefulness of endoscopic ultrasound for acquiring the pathological diagnosis of gastrointestinal lymphoma

Background and study aimsThis study aims to assess the value of endoscopic ultrasound (EUS) for acquiring a pathological diagnosis of gastrointestinal lymphoma (GIL). Patients and methodsWe retrospectively reviewed all GIL patients who underwent EUS from November 2011 to July 2020 at Fudan University Shanghai Cancer Center. All patients with pathologically confirmed GIL were included. The characteristics of the lesions were recorded, and the efficacy for acquiring pathologic diagnosis between white light endoscopy (WLE) and EUS was analyzed. ResultsIn total, 404 patients with GIL who underwent EUS examination were included in this study. GIL was confirmed in 143 cases by after EUS judgment biopsy (AEJ biopsy), 11 cases by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), 293 cases by WLE biopsy, and 10 cases by surgical pathology for repeated negative pathologic results from EUS and WLE. Among all cases, 78.71% (318/404) were T1-T2, whereas 32.18% (130/404) were determined to have multiple lesions in the digestive tract wall. The positive rates of the WLE biopsy and AEJ biopsy of the involved gastric wall were 77.93% (293/376) and 89.38% (143/160), respectively. Twelve cases showed diffuse thickening of the gastric wall, and the total positive rate of EUS was 91.67% but 0% for WLE with this type of GIL. The total positive rate and positive rate during the first examination of EUS were all significantly higher than those of WLE. Moreover, 19.68% of the patients showed negative results during their WLE examination and then received a positive pathologic diagnosis upon EUS examination, but none had the opposite process. ConclusionsEUS was found to be a better tool for acquiring a pathological diagnosis of GIL than conventional WLE, especially for GIL similar to linitis plastica.

Confocal laser endomicroscopy in gastro-intestinal endoscopy: technical aspects and clinical applications.

Confocal laser endomicroscopy (CLE) is an advanced endoscopic imaging technology that provides a magnified, cellular level view of gastrointestinal epithelia. In conjunction with topical or intravenous fluorescent dyes, CLE allows for an "optical biopsy" for real-time diagnosis. Two different CLE system have been used in clinical endoscopy, probe-based CLE (pCLE) and endoscope-based CLE (eCLE). Using pCLE, the device can be delivered: (I) into the luminal gastrointestinal tract through the working channel of standard endoscopes; (II) into extraluminal cystic and solid parenchymal lesions through an endoscopic ultrasound (EUS) needle; or (III) into the biliary system through an endoscopic retrograde cholangiopancreatography (ERCP) accessory channel. With eCLE, the probe is directly integrated into the tip of a conventional endoscope, however, these endoscopes are no longer commercially available. CLE has moderate to high diagnostic accuracy for neoplastic and inflammatory conditions through the gastrointestinal tract including: oesophageal, gastric and colonic neoplasia, pancreatic cysts and solid lesions, malignant pancreatobiliary strictures and inflammatory bowel disease. Some studies have demonstrated the diagnostic benefit of CLE imaging when combined with either conventional white light endoscopy or advanced imaging technologies. Therefore, optical biopsies using CLE can resolve diagnostic dilemmas in some cases where conventional imaging fails to achieve conclusive results. CLE could also reduce the requirement for extensive tissue sampling during surveillance procedures. In the future, CLE in combination with molecular probes, could allow for the molecular characterization of diseases and assess response to targeted therapy. However, the narrow field of view, high capital costs and specialized operator training requirements remain the main limitations. Future multi-center, randomized trials with a focus on conventional diagnostic applications, cost-effectiveness and standardized training will be required for definitive evidence. The objective of this review is to evaluate the technical aspects and current applications of CLE in patients with gastrointestinal and pancreatobiliary diseases and discuss future directions for this technique.

Magnifying endoscopy for the diagnosis of early gastric cancer: Establishment of technique, diagnostic system, and scientific evidence from Japan

Magnifying endoscopy for the diagnosis of early gastric cancer: Establishment of technique, diagnostic system, and scientific evidence from Japan

Improving tissue characterization, differentiation and diagnosis in gynecology with the narrow-band imaging technique: A systematic review.

Narrow-band imaging (NBI), an on-demand, real-time endoscopic imaging technique, was developed to enhance visualization of the mucosal vascular network and surface texture. The present article provides a systematic review of studies that assessed the use of NBI in gynecological endoscopy. The following electronic databases were searched: PubMed (1950-2020), Google Scholar (2004-2020) and Cochrane Library (2010-2020). In the initial search, 3,836 entries were identified, of which 31 were finally included in the systematic review. Of the selected studies, 10 (32%) were case reports, 19 (61.2%) were prospective studies and 2 (6.4%) were randomized controlled trials with control groups. The selected studies reported on the use of NBI in hysteroscopy, laparoscopy and colposcopy. It was revealed that NBI utilization in hysteroscopy increased the accuracy, sensitivity and specificity in detecting malignant and premalignant lesions. NBI improved the specificity and sensitivity in the detection of endometriotic lesions and cervical lesions. Conventional white light endoscopy in gynecology may be significantly improved by the use of NBI. Further studies with larger cohorts and improved design are required to achieve more reliable results. It is of special interest that utilization of this method requires apparatus which is expensive; concerns are the long training and experience of staff required and the long learning curve.

Endoscopic Diagnosis for H. pylori Infection: White Light Imaging (WLI) vs. Image-Enhanced Endoscopy (IEE).

Helicobacter pylori infection is a class I carcinogen that can lead to gastric cancer. Early diagnosis and eradication of H. pylori infection are important to eliminate the risk of gastric cancer. Several invasive diagnostic techniques require biopsy samples, resulting in avoidable injury and medical expense. Furthermore, due to the localized distribution of H. pylori, random biopsies are not always reliable in diagnosing H. pylori infection. This article aimed to review endoscopic findings and new endoscopic options for the diagnosis of H. pylori infection. Using conventional white light imaging (WLI) and image-enhanced endoscopy (IEE), the endoscopic features associated with histological changes have increasingly become apparent. Real-time endoscopy is essential to make a diagnosis of H. pylori infection and allow targeted biopsy. Image-enhanced endoscopy (IEE), such as narrow-band imaging (NBI), linked color imaging (LCI), and blue laser imaging (BLI), enhances visualization of the surface vascular pattern and provides accurate diagnostic performance in H. pylori infection, as well as gastric neoplastic lesions, compared to conventional white light endoscopy. In conclusion, the new endoscopic technologies could be used in current practice with conventional white light endoscopy for accurate and real-time diagnosis of H. pylori infection and pre-cancerous lesions.

White-light endoscopy is insufficient to distinguish between types of esophageal white lesions.

Esophageal white lesions (EWL) are commonly observed under upper endoscopy, while their clinical significance remains undetermined. The aim of this study was to identify the endoscopic characteristics of EWL and distinguish between different types of EWL. Consecutive patients with upper gastrointestinal complaints and participants admitted for health check-up who underwent esophagogastroduodenoscopy from October 2018 to August 2019 in a tertiary hospital were prospectively screened. EWL were detected under endoscopy and biopsy was performed for histological analysis. Participants' characteristics, lifestyle, esophageal motility and reflux monitoring variables were analyzed. Of the 3641 consecutive participants screened, 303 of them aged 56.12 ± 10.95 years were found to have EWL (detection rate of 8.3%). More than one-third of them preferred hot drinks, eating pickled or spicy food, smoking and alcohol consumption and 5.3% had current or former upper gastrointestinal or head and neck cancers. The common endoscopic appearance of the EWL (2.9 mm ± 1.2 mm in diameter) included slightly elevated plaque, translucent white in color, with a clear border, round or oval in shape, and a scaly, rough or smooth surface. Histology showed low-grade intraepithelial dysplasia in 13 cases, leukoplakia in 10 and intestinal metaplasia in one. No significant differences were found between the histological findings and endoscopic manifestations of EWL. EWL are not uncommon in daily endoscopic examination, with some of them being precancerous lesions. Conventional white-light endoscopy is insufficient to identify EWL, while histological assessment is important. Further studies using advanced endoscopic techniques with long-term follow-up are needed.

Time to Move Forward for Image Enhanced ‎Endoscopy even in Resource Limited Areas

Proper early detection of GI lesions is the key factor for improving patients’ prognosis and improving quality of care. It is our duty as a gastroenterologist offering endoscopic screening and diagnostic services to do the best for our patients care. In clinical studies, IEE outperformed conventional white-light endoscopy in diagnosing lesions and identifying their morphologies. Large-scale studies on various lesions for standardization of findings and training are needed. It is also hoped that every center could adopt the technology of IEE for better outcomes and quality.