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

Visibility Evaluation of Fundic Gland Polyp Associated With Proton Pump Inhibitor in Texture and Color Enhancement Imaging

Objectives

A 'gray color sign' (GCS) is a new endoscopic feature of fundic gland polyp associated with proton pump inhibitor (PPI-FGP). Here, we compare the ability of texture and color enhancement imaging (TXI) to white light imaging (WLI) with regard to the detection of GCS.

Methods

In this prospective study, 19 consecutive patients with PPI-FGP were enrolled at our hospital from April 2021 to October 2022. Endoscopic images of PPI-FGP using WLI, TXI mode1 (TXI-1), TXI mode2 (TXI-2), and narrow-band imaging (NBI) were collected and compared by 10 endoscopists. Visibility of GCS by each mode (Image enhancement endoscopy) was scored as follows: 5, improved; 4, somewhat improved; 3, equivalent; 2, somewhat decreased; and 1, decreased. The inter-rater reliability (intra-class correlation coefficient, ICC) was also evaluated. The images were objectively evaluated based on L* a* b* color values and the color difference (ΔE*) in the CIE LAB color space system.

Results

Improved visibility of GCS compared with WLI was achieved for: TXI-1: 82.6%, TXI-2: 86.9%, and NBI: 0% for all endoscopists. Total visibility scores were: TXI-1, 44.9; TXI-2, 42.9; NBI, 17.4 for all endoscopists. Visibility scores were significantly higher using TXI-1 and TXI-2 compared with NBI (p < 0.01). The inter-rater reliability for TXI-1 and TXI-2 was "excellent" for all endoscopists. The use of ΔE* revealed statistically significant differences between WLI and TXI-1 (p < 0.01).

Conclusions

TXI is an improvement over WLI for the visualization of GCS, and can be used by both trainee and expert endoscopists with equal efficiency and accuracy.

Visibility evaluation of gastric epithelial neoplasm of fundic gland mucosa lineage using texture and color enhancement imaging

Objectives

Recently, the incidence of Helicobacter pylori-uninfected gastric cancers, such as gastric epithelial neoplasm of fundic-gland mucosa lineage (GEN-FGML), has increased with the widespread use of eradication therapy. Because the detection and endoscopic diagnosis of GEN-FGML are difficult, an effective observation method in screening endoscopy is required. We investigated whether texture and color enhancement imaging (TXI) improved the visibility of GEN-FGML compared with white light imaging (WLI).

Methods

In this single-center prospective clinical study, 50 GEN-FGML lesions (35 patients) treated at our hospital between October 2020 and June 2023 were analyzed. The endoscopic images of GEN-FGML obtained using WLI, TXI mode 1 (TXI-1), TXI mode 2 (TXI-2), and narrow-band imaging were compared by 10 endoscopists. We analyzed the visibility score and inter-rater reliability (intraclass correlation coefficient and conducted an objective evaluation based on L* a* b* color values and the color difference (ΔE*) in the CIE LAB color space system.

Results

Histologically, GEN-FGML was classified as gastric adenocarcinoma of fundic-gland type (n = 45) and gastric adenocarcinoma of fundic-gland mucosa type (n = 5). The total visibility score for all endoscopists was significantly higher for TXI than for WLI (p < 0.01); and for TXI-1 than for TXI-2 (p < 0.01). The intraclass correlation coefficients for TXI-1 and TXI-2 were "almost perfect" and "substantial," respectively, for all endoscopists. ΔE* was significantly higher for TXI than for WLI (p < 0.01).

Conclusions

TXI improved the visibility of GEN-FGML for all endoscopists compared with WLI when evaluated subjectively and objectively.

Visibility of esophageal squamous cell carcinoma under iodine staining on texture and color enhancement imaging

OBJECTIVE

Iodine staining on white light imaging (WLI) is the gold standard for detecting and demarcating esophageal squamous cell carcinoma (ESCC). We examined the effects of texture and color enhancement imaging (TXI) on improving the endoscopic visibility of ESCC under iodine staining.

METHODS

Twenty ESCC lesions that underwent endoscopic submucosal dissection were retrospectively included. The color difference between ESCC and the surrounding mucosa (ΔEe) on WLI, TXI, and narrow-band imaging was assessed, and ΔEe under 1% iodine staining on WLI and TXI. Furthermore, the visibility grade determined by endoscopists was evaluated on each imaging.

RESULT

The median ΔEe was greater on TXI than on WLI (14.53 vs. 10.71, respectively; p < 0.005). Moreover, the median ΔEe on TXI under iodine staining was greater than the median ΔEe on TXI and narrow-band imaging (39.20 vs. 14.53 vs. 16.42, respectively; p < 0.005 for both). A positive correlation in ΔEe under iodine staining was found between TXI and WLI (correlation coefficient = 0.61, p < 0.01). Moreover, ΔEe under iodine staining on TXI in each lesion was greater than the corresponding ΔEe on WLI. The visibility grade assessed by endoscopists on TXI was also significantly greater than that on WLI under iodine staining (p < 0.01).

CONCLUSIONS

The visibility of ESCC after iodine staining was greater on TXI than on WLI.

Image-enhanced endoscopy in upper gastrointestinal disease: focusing on texture and color enhancement imaging and red dichromatic imaging

Endoscopic examination plays a crucial role in the diagnosis of upper gastrointestinal (UGI) tract diseases. Despite advancements in endoscopic imaging, the detection of subtle early cancers and premalignant lesions using white-light imaging alone remains challenging. This review discusses two novel image-enhanced endoscopy (IEE) techniques-texture and color enhancement imaging (TXI) and red dichromatic imaging (RDI)-and their potential applications in UGI diseases. TXI enhances texture, brightness, and color tone, which improves the visibility of mucosal irregularities and facilitates earlier detection of neoplastic lesions. Studies have suggested that TXI enhances the color differences between lesions and the surrounding mucosa and improves the visibility of the lesion. TXI aids in the diagnosis of various UGI diseases, including early gastric cancer, esophageal cancer, premalignant conditions such as atrophic gastritis and Barrett's esophagus, and duodenal tumors. RDI utilizes specific wavelengths to enhance the visualization of deep blood vessels or bleeding points, aiding in the rapid and accurate identification of bleeding sources during endoscopic procedures. Although promising, TXI and RDI require further large-scale studies across diverse populations to establish their clinical utility, diagnostic performance, and cost-effectiveness before integration into the guidelines. Standardized training is also required for effective utilization. Overall, these IEE techniques has the potential to improve the diagnosis and management of UGI.

Comparison of Effective Imaging Modalities for Detecting Gastric Neoplasms: A Randomized 3-Arm Phase II Trial

INTRODUCTION

The early detection of gastric neoplasms (GNs) leads to favorable treatment outcomes. The latest endoscopic system, EVIS X1, includes third-generation narrow-band imaging (3G-NBI), texture and color enhancement imaging (TXI), and high-definition white-light imaging (WLI). Therefore, this randomized phase II trial aimed to identify the most promising imaging modality for GN detection using 3G-NBI and TXI.

METHODS

Patients with scheduled surveillance endoscopy after a history of esophageal cancer or GN or preoperative endoscopy for known esophageal cancer or GN were randomly assigned to the 3G-NBI, TXI, or WLI groups. Endoscopic observations were performed to detect new GN lesions, and all suspected lesions were biopsied. The primary endpoint was the GN detection rate during primary observation. Secondary endpoints were the rate of missed GNs, early gastric cancer detection rate, and positive predictive value for a GN diagnosis. The decision rule had a higher GN detection rate between 3G-NBI and TXI, outperforming WLI by >1.0%.

RESULTS

Finally, 901 patients were enrolled and assigned to the 3G-NBI, TXI, and WLI groups (300, 300, and 301 patients, respectively). GN detection rates in the 3G-NBI, TXI, and WLI groups were 7.3, 5.0, and 5.6%, respectively. The rates of missed GNs were 1.0, 0.7, and 1.0%, the detection rates of early gastric cancer were 5.7, 4.0, and 5.6%, and the positive predictive values for the diagnosis of GN were 36.5, 21.3, and 36.8% in the 3G-NBI, TXI, and WLI groups, respectively.

DISCUSSION

Compared with TXI and WLI, 3G-NBI is a more promising modality for GN detection.

Effect of texture and color enhancement imaging on the visibility of gastric tumors

Texture and color enhancement imaging (TXI) may improve the visibility of gastric tumors and allow their early detection. However, few reports have examined the utility of TXI. Between June 2021 and October 2022, 56 gastric tumors in 51 patients undergoing endoscopic submucosal dissection at Fukuchiyama City Hospital were evaluated preoperatively using conventional white light imaging (WLI), narrow-band imaging (NBI), and TXI modes 1 and 2. The color differences of the tumors and surrounding mucosae were evaluated using the CIE 1976 L*a*b color space, Additionally, the visibility scores were scaled. Of the 56 gastric tumors, 45 were early gastric cancers, and 11 were adenomas. Overall, the color difference in TXI mode 1 was considerably higher compared to WLI (16.36 ± 7.05 vs. 10.84 ± 4.05; p < 0.01). Moreover, the color difference in early gastric cancers was considerably higher in TXI mode 1 compared to WLI, whereas no significant difference was found in adenomas. The visibility score in TXI mode 1 was the highest, and it was significantly higher compared to WLI. Regarding adenomas, the visibility score in TXI mode 1 was also significantly higher compared to that in WLI. TXI may provide improved gastric tumor visibility.

Topic highlight on texture and color enhancement imaging in gastrointestinal diseases

Olympus Corporation developed texture and color enhancement imaging (TXI) as a novel image-enhancing endoscopic technique. This topic highlights a series of hot-topic articles that investigated the efficacy of TXI for gastrointestinal disease identification in the clinical setting. A randomized controlled trial demonstrated improvements in the colorectal adenoma detection rate (ADR) and the mean number of adenomas per procedure (MAP) of TXI compared with those of white-light imaging (WLI) observation (58.7% vs 42.7%, adjusted relative risk 1.35, 95%CI: 1.17-1.56; 1.36 vs 0.89, adjusted incident risk ratio 1.48, 95%CI: 1.22-1.80, respectively). A cross-over study also showed that the colorectal MAP and ADR in TXI were higher than those in WLI (1.5 vs 1.0, adjusted odds ratio 1.4, 95%CI: 1.2-1.6; 58.2% vs 46.8%, 1.5, 1.0-2.3, respectively). A randomized controlled trial demonstrated non-inferiority of TXI to narrow-band imaging in the colorectal mean number of adenomas and sessile serrated lesions per procedure (0.29 vs 0.30, difference for non-inferiority -0.01, 95%CI: -0.10 to 0.08). A cohort study found that scoring for ulcerative colitis severity using TXI could predict relapse of ulcerative colitis. A cross-sectional study found that TXI improved the gastric cancer detection rate compared to WLI (0.71% vs 0.29%). A cross-sectional study revealed that the sensitivity and accuracy for active Helicobacter pylori gastritis in TXI were higher than those of WLI (69.2% vs 52.5% and 85.3% vs 78.7%, respectively). In conclusion, TXI can improve gastrointestinal lesion detection and qualitative diagnosis. Therefore, further studies on the efficacy of TXI in clinical practice are required.

Advanced diagnostic endoscopy in the upper gastrointestinal tract: Review of the Japan Gastroenterological Endoscopic Society core sessions

The Japan Gastroenterological Endoscopy Society (JGES) held four serial symposia between 2021 and 2022 on state-of-the-art issues related to advanced diagnostic endoscopy of the upper gastrointestinal tract. This review summarizes the four core sessions and presents them as a conference report. Eleven studies were discussed in the 101st JGES Core Session, which addressed the challenges and prospects of upper gastroenterological endoscopy. Ten studies were also explored in the 102nd JGES Core Session on advanced upper gastrointestinal endoscopic diagnosis for decision-making regarding therapeutic strategies. Moreover, eight studies were presented during the 103rd JGES Core Session on the development and evaluation of endoscopic artificial intelligence in the field of upper gastrointestinal endoscopy. Twelve studies were also discussed in the 104th JGES Core Session, which focused on the evidence and new developments related to the upper gastrointestinal tract. The endoscopic diagnosis of upper gastrointestinal diseases using image-enhanced endoscopy and AI is one of the most recent topics and has received considerable attention. These four core sessions enabled us to grasp the current state-of-the-art in upper gastrointestinal endoscopic diagnostics and identify future challenges. Based on these studies, we hope that an endoscopic diagnostic system useful in clinical practice is established for each field of upper gastrointestinal endoscopy.

Texture and color enhancement imaging improves the visibility of gastric neoplasms: clinical trial with image catalogue assessment using conventional and newly developed endoscopes

BACKGROUND

Texture and color enhancement imaging (TXI) enhances the changes in endoscopic features caused by gastric neoplasms, such as redness/whiteness and elevation/depression. This study aimed to demonstrate the effectiveness of TXI in improving the visibility of gastric neoplasms compared with white light imaging (WLI) using conventional (CE) and newly developed endoscopes (NE).

METHODS

We recruited patients who were histologically diagnosed with gastric neoplasms; endoscopy was performed, and gastric neoplasms photographed using three imaging modalities, including WLI, TXI mode 1 (TXI-1) and TXI mode 2 (TXI-2). Two different endoscopes (CE and NE) were used for the same patients. Six endoscopists provided the visibility scale scores ranging from 1 (poor) to 4 (excellent) for gastric neoplasms. The primary outcome was the visibility scale scores based on each modality and endoscope. The secondary outcome was the identification of factors including H. pylori infection, atrophy, location, size, morphology, histological diagnosis and intestinal metaplasia that affect the differences in visibility scale scores between TXI-1/TXI-2 and WLI.

RESULTS

Fifty-two gastric neoplasms were analyzed. The mean visibility scale scores with the NE were 2.79 ± 1.07, 3.23 ± 0.96 and 3.14 ± 0.92 for WLI, TXI-1 and TXI-2, respectively. The mean visibility scales with the CE were 2.53 ± 1.10, 3.04 ± 1.05 and 2.96 ± 1.92 for WLI, TXI-1 and TXI-2, respectively. For both endoscopes, significant differences were observed in visibility scale scores between WLI and TXI-1 (p < 0.001) and between WLI and TXI-2 (p < 0.001). The visibility scale scores of NE were superior to those of CE in all modalities. In the secondary outcome, there was no factor affected the differences of visibility scale scores between TXI-1/TXI-2 and WLI.

CONCLUSIONS

This study demonstrated that TXI-1 and TXI-2 enhanced the visibility scale scores of gastric neoplasms compared with that of WLI. Moreover, newly developed endoscope has the potential to improve visibility compared to conventional endoscope.

TRIAL REGISTRATION

This study was registered with the University Hospital Medical Information Network (UMIN000042429, 16/11/2020).

Image enhanced colonoscopy: updates and prospects-a review

Colonoscopy has been proven to be a successful approach in both identifying and preventing colorectal cancer. The incorporation of advanced imaging technologies, such as image-enhanced endoscopy (IEE), plays a vital role in real-time diagnosis. The advancements in endoscopic imaging technology have been continuous, from replacing fiber optics with charge-coupled devices to the introduction of chromoendoscopy in the 1970s. Recent technological advancements include "push-button" technologies like autofluorescence imaging (AFI), narrowed-spectrum endoscopy, and confocal laser endomicroscopy (CLE). Dye-based chromoendoscopy (DCE) is falling out of favor due to the longer time required for application and removal of the dye and the difficulty of identifying lesions in certain situations. Narrow band imaging (NBI) is a technology that filters the light used for illumination leading to improved contrast and better visibility of structures on the mucosal surface and has shown a consistently higher adenoma detection rate (ADR) compared to white light endoscopy. CLE has high sensitivity and specificity for polyp detection and characterization, and several classifications have been developed for accurate identification of normal, regenerative, and dysplastic epithelium. Other IEE technologies, such as blue laser imaging (BLI), linked-color imaging (LCI), i-SCAN, and AFI, have also shown promise in improving ADR and characterizing polyps. New technologies, such as Optivista, red dichromatic imaging (RDI), texture and color enhancement imaging (TXI), and computer-aided detection (CAD) using artificial intelligence (AI), are being developed to improve polyp detection and pathology prediction prior to widespread use in clinical practice.