Higher detectability of gastric cancer after Helicobacter pylori eradication in texture and color enhancement imaging mode 2 in screening endoscopy

Objectives

The utility of texture and color enhancement imaging (TXI) in detecting gastric cancer (GC) has been investigated. However, few reports exist on TXI mode2 (TXI2) used for detecting GC; this study investigated the efficacy of TXI2 in GC detection during screening endoscopy.

Methods

This study enrolled 13,440 participants with confirmed Helicobacter pylori (H. pylori) infection status who underwent screening endoscopy by 20 endoscopists in our health screening center. The participants were divided into two groups: one group was observed using white light imaging (WLI) only by 17 endoscopists (WLI group, 10,745 participants), and the other group was observed using TXI2 only by the other three endoscopists (TXI2 group, 2695 participants). We analyzed the detection rate and the characteristics of GC. In addition, considering the bias due to the diagnostic ability, we analyzed the subset of the WLI group where the participants were evaluated by the top three endoscopists based on their GC detection rate (Expert-WLI group, 2792 participants) for comparison with the TXI2 group.

Results

Fifty patients were diagnosed with GC. The GC detection rates were 0.68% and 0.71% in the Expert-WLI and TXI2 groups, respectively. In patients who underwent screening endoscopy after H. pylori eradication, the detection rates of differentiated GC, L-region lesions, and surface depressed-type lesions were 0.52%, 0%, and 0.43% in the Expert-WLI group and 1.36%, 0.78%, and 1.36% in the TXI2 group, respectively.

Conclusions

In screening endoscopy, the detectability of differentiated GC and L-region lesions and surface depressed-type lesions after H. pylori eradication was higher in TXI2.

Clinical usefulness of image-enhanced endoscopy for the diagnosis of ulcerative colitis-associated neoplasia

Patients with a long history of ulcerative colitis (UC) are at risk of developing a significant complication known as UC-associated neoplasia (UCAN). To reduce the risk of UCAN and the associated mortality, the current guidelines recommend initiating surveillance colonoscopy 8-10 years after confirmation of UC diagnosis. In recent years, advancements in endoscopic diagnostic technologies, including magnifying and image-enhancing techniques, have allowed for the production of high-contrast images that emphasize mucosal structures, vascular patterns, and color tones. Recently, image-enhanced endoscopy technologies have become available and offer the potential to improve the qualitative endoscopic assessment of UCAN. The use of high-definition chromoendoscopy enables the evaluation of subtle mucosal patterns in the colon. Magnifying narrow-band imaging facilitates the visualization of mucosal vascular structures. Texture and color enhancement imaging processes structure, color tone, and brightness aspects more appropriately, whereas linked color imaging optimizes the emphasis on mucosal and vascular redness. Both techniques are expected to excel in the depiction of subtle color variations and mucosal changes characteristic of UCAN. This article provides an overview of the current status and future challenges regarding the use of various image-enhanced endoscopy techniques in the diagnosis of UCAN.

The usefulness of texture and color enhancement imaging to identify the minor papilla orifice

In clinical cases of pancreas divisum, endoscopic retrograde cholangiopancreatography often necessitates cannulation of the pancreatic duct through the minor papilla. Nevertheless, this procedure can be challenging because of the small size of the minor papilla and the difficulty in visualizing the ductal orifice. A new image-enhanced endoscopy technique called texture and color enhancement imaging (TXI) has been developed, which enhances texture, brightness, and color compared with white-light imaging, resulting in subtle differences in the surface mucosa. Herein, we describe the case of a 73-year-old man with pancreas divisum in whom TXI was useful in identifying the orifice of the minor papilla. He was referred to our hospital with repetitive acute exacerbation of chronic pancreatitis. Since contrast-enhanced computed tomography revealed a pancreatic stone in the main pancreatic duct, endoscopic retrograde cholangoepancreatography was performed as a therapeutic intervention. Despite the initial difficulty in identifying the orifice of the minor papilla on white-light imaging, TXI enhanced its visibility successfully, enabling dorsal pancreatic duct cannulation via the minor papilla. Subsequently, endoscopic pancreatic sphincterotomy was performed and a 6Fr plastic stent was placed. Post-endoscopic therapy, the patient's abdominal pain was relieved. TXI was useful in identifying the minor papilla orifice and led to successful cannulation.

Usefulness of texture and color enhancement imaging in peroral pancreatoscopy

Tanisaka and colleagues report the usefulness of texture and color enhancement imaging provided by a new-generation image-enhanced endoscopy system in a patient with intraductal papillary mucinous neoplasm who had undergone peroral pancreatoscopy. Texture and color enhancement imaging clearly showed structural changes of the lesion and improved the diagnostic quality of peroral pancreatoscopy.

Gastric squamous metaplasia observed by image-enhanced endoscopy

A 61-year-old Helicobacter pylori-positive female with gastroesophageal reflux disease has undergone surveillance endoscopy every year for 13 years at Tokyo Medical University Hospital. At the first surveillance in 2009, conventional white light endoscopy showed a 10-mm whitish slightly depressed lesion at the lesser curvature of the gastric cardia. This lesion gradually increased in size to 15 mm over the 13-year observational period. Indigo carmine chromoendoscopy, narrow band imaging, and texture and color enhancement imaging in both mode 1 and mode 2 clearly emphasized the presence of a depressed whitish mucosa around the gastric mucosa compared with white light imaging. None of the three image-enhanced endoscopy techniques showed any abnormality in the vascular or structural pattern. Pathological findings showed squamous epithelium without atypia and revealed no evidence of malignancy in the stomach. We thus report a case of gastric squamous metaplasia without gastric neoplastic lesion in the gastric cardia whose lesions were endoscopically observed to change the size for more than 10 years and whose lesions were endoscopically evaluated with a texture and color enhancement imaging mode 1 and mode 2 and narrow band imaging.

Usefulness of third-generation narrow band imaging and texture and color enhancement imaging in improving visibility of superficial early gastric cancer: A study using color difference

OBJECTIVES

Overlooking early gastric cancer (EGC) during endoscopy is an issue to be resolved. Image-enhanced endoscopy is expected to improve EGC detection. This study investigated the usefulness of third-generation narrow band imaging (3G-NBI) and texture and color enhancement imaging (TXI) in improving the visibility of EGC using the color difference between EGC and its surrounding gastric mucosa.

METHODS

In this retrospective observational study, we examined 51 superficial EGCs that underwent endoscopic submucosal dissection and were observed by all three methods: 3G-NBI, TXI, and white light imaging (WLI). The primary endpoint was to compare the color difference of each method. For each EGC, we prepared one non-magnifying image for each method so that the location and size of the lesion in each image were the same. The L*a*b* color space was used to evaluate the color values. When the color values of the cancerous lesion and its surrounding mucosa were (L*c, a*c, b*c) and (L*s, a*s, b*s), respectively, the color difference was defined to be [(L*c-L*s)2+(a*c-a*s)2+(b*c-b*s)2]1/2.

RESULTS

The median color difference was 9.2 (interquartile range, 5.3-15.7) in WLI, 13.5 (interquartile range, 9.4-19.5) in 3G-NBI, and 15.3 (interquartile range, 9.1-22.1) in TXI. Statistically, the color difference was significantly larger in 3G-NBI than in WLI (p < 0.001) and TXI compared with WLI (p < 0.001). However, there was no significant difference between 3G-NBI and TXI (p = 0.330).

CONCLUSIONS

Regarding color difference, both 3G-NBI and TXI were estimated to be more useful than WLI in improving the visibility of superficial EGC.

Distinguishing the papilla of Vater during biliary cannulation using texture and color enhancement imaging: A pilot study

Objectives

Understanding the exact morphology of the bile duct opening is important for determining the success of bile duct cannulation. Texture and color enhancement imaging (TXI) has been reported to enhance slight changes in color tone and structure that are difficult to see with white light imaging. This study investigated whether TXI mode1 could improve papillary recognition by trainees inexperienced in endoscopic retrograde cholangiopancreatography.

Methods

We included 31 patients with naive papilla of Vater at a single institution in the study. Trainee endoscopists (n = 4) evaluated and identified the papilla according to the Inomata classification using white light imaging and TXI. The degree of agreement with the evaluation of supervising physicians (n = 4) was examined using the McNemar test.

Results

In the trainee group, the kappa coefficient agreements were κ = 0.346 and κ = 0.754 for white light imaging and TXI, respectively. When further evaluated, the separate and septal types of papilla groups showed an increased concordance rate in one of the four trainees (76.67%–96.67%, p = 0.031, respectively). Moreover, comparison for two‐group evaluation showed an increased kappa coefficient in two of four trainees (0.34–0.92, p = 0.010, 0.45–0.92, p = 0.024).

Conclusions

Observation of the duodenal papilla using TXI improved papillary differentiation and suggested the potential of TXI as a clinical tool. Further study of this method is necessary; it is expected to help reduce cannulation time and the incidence of pancreatitis.

Third-Generation High-Vision Ultrathin Endoscopy Using Texture and Color Enhancement Imaging and Narrow-Band Imaging to Evaluate Barrett's Esophagus

It remains unclear whether texture- and color-enhancement imaging (TXI) and narrow-band imaging (NBI) provide an advantage over white-light imaging (WLI) in Barrett’s esophagus. We compared endoscopic findings and color differences between WLI and image-enhanced endoscopy (IEE) using a third-generation ultrathin endoscope. We retrospectively enrolled 40 patients who evaluated Barrett’s esophagus using WLI, TXI, and NBI. Color differences determined using the International Commission on Illumination 1976 (L∗, a∗, b∗) color space among Barrett’s epithelium, esophageal, and gastric mucosa were compared among the endoscopic findings. As the secondary outcome, we assessed the subjective visibility score among three kinds of endoscopic findings. The prevalence of Barrett’s esophagus and gastroesophageal reflux disease (GERD) in WLI was 82.5% and 47.5%, respectively, and similar among WLI, TXI, and NBI. Color differences between Barrett’s epithelium and esophageal or gastric mucosa on NBI were significantly greater than on WLI (all p < 0.05). However, the color difference between Barrett’s epithelium and esophageal mucosa was significantly greater on NBI than TXI (p < 0.001), and the visibility score of Barrett’s epithelium detection was significantly greater on TXI than NBI (p = 0.022), and WLI (p = 0.016). High-vision, third-generation ultrathin endoscopy using NBI and TXI is useful for evaluating Barrett’s epithelium and GERD compared with WLI alone.

Emerging texture and color enhancement imaging in early gastric cancer

Screening endoscopy improves detection and prognosis of patients with gastric cancer. However, even expert endoscopists can miss early gastric cancer under standard white light imaging. Texture and color enhancement imaging (TXI) is an image-enhanced endoscopy that enhances brightness, surface irregularities such elevation or depression, and subtle color changes. A few image-oriented studies have compared the gastric color differences between neoplastic and peripheral areas under both white light imaging and TXI. The results not only suggested that the overall color differences to be more pronounced in TXI, but also that TXI mode 1 was superior to white light imaging in the visibility of early gastric cancer. Despite the promising results in these initial studies, it is unclear whether the superiority of the image-enhanced endoscopy will translate into an improvement in early gastric cancer detection in real practice. Therefore, large-scale prospective studies are necessary to investigate the efficacy of this new technology in the evaluation of patients undergoing screening endoscopy.

Two cases of colonic tumors observed by linked color imaging and texture and color enhancement imaging with the tablet-image comparison method

An endoscope system using 5‐color light‐emitting diodes (LEDs) (EVIS X1: CV‐1500, Olympus Co., Tokyo, Japan) was released worldwide in July 2020. In addition to the improvement of narrow band imaging (NBI), this system enables texture and color enhancement imaging (TXI). TXI makes the lesion reddish and supports better visibility of colorectal lesions in comparison to white light imaging for improving lesion detection. On the other hand, another 4‐color LED endoscope system (ELUXEO: BL‐7000; Fujifilm, Tokyo, Japan) has been on the market in the West since 2017. This system enables blue light imaging (BLI) and linked color imaging (LCI). Generally, the accurate comparison between two images obtained by two different endoscope systems is difficult. To resolve this problem, we developed a method named the tablet‐image comparison (TIC) method. TIC is a simple, easy, and paperless method to get images under similar conditions of two endoscope systems for an accurate comparison. We herein report two colorectal lesions in which accurate comparisons of images between TXI and LCI and between improved NBI and BLI obtained in the EVIS X1 and ELUXEO systems were performed using the TIC method. One was IIa 30 mm (high‐grade dysplasia) and the other was IIa 25 mm (low‐grade adenoma). A detailed comparison between TXI and LCI could be performed by TIC. In these two cases, with a distant view, TXI showed greater redness than LCI. LCI showed slightly higher brightness than TXI. In magnified TXI and LCI, the irregularities observed were similar to NBI and BLI, respectively.

Texture and Color Enhancement Imaging Increases Color Changes and Improves Visibility for Squamous Cell Carcinoma Suspicious Lesions in the Pharynx and Esophagus

Texture and color enhancement imaging (TXI) has been developed as an image-enhanced endoscopy technology. TXI mode2 enhances texture and brightness, and TXI mode1 also enhances color. This study aims to assess the color differences in squamous cell carcinoma (SCC) suspicious lesions in the pharynx and esophagus using white light imaging (WLI), TXI mode1, TXI mode2, and narrow-band imaging (NBI). A total of 59 SCC suspicious lesions from 30 patients were analyzed. The color differences (ΔE) between the lesion and the surrounding mucosa were calculated for each modality. The color value was assessed using the Commission Internationale d’Eclairage L*a*b* color space. The visibility of the lesion in each modality was evaluated and compared to that in the WLI by six endoscopists. The mean ΔE values in the WLI, TXI mode1, TXI mode2, and NBI were 11.6; 18.6; 14.3; and 17.2, respectively, and the ΔE values of TXI mode1, TXI mode2, and NBI were significantly higher than those of the WLI (p < 0.001). No lesions had worse visibility, and 62.5% (37/59) had improved visibility, as assessed by more than half of the endoscopists in TXI mode1. TXI mode1 can enhance color changes and improve the visibility of SCC suspicious lesions in the pharynx and esophagus, compared to WLI.

Fundamentals, Diagnostic Capabilities and Perspective of Narrow Band Imaging for Early Gastric Cancer

The development of image-enhanced endoscopy has dramatically improved the qualitative and quantitative diagnosis of gastrointestinal tumors. In particular, narrow band imaging (NBI) has been widely accepted by endoscopists around the world in their daily practice. In 2009, Yao et al. proposed vessel plus surface (VS) classification, a diagnostic algorithm for early gastric cancer using magnifying endoscopy with NBI (ME-NBI), and in 2016, Muto et al. proposed a magnifying endoscopy simple diagnostic algorithm for early gastric cancer (MESDA-G) based on VS classification. In addition, the usefulness of ME-NBI in the differential diagnosis of gastric cancer from gastritis, diagnosis of lesion extent, inference of histopathological type, and diagnosis of depth has also been investigated. In this paper, we narrative review the basic principles, current status, and future prospects of NBI.