Narrow Band Imaging Research Articles

Uncommon Presentation of Gastric Heterotopia Manifesting as a Polypoid Mass

Introduction: Gastric heterotopia (GH) is characterized by the presence of differentiated gastric mucosa tissue outside the stomach, with the most common site being the proximal esophagus, known as the inlet patch. Complications have been reported, but polyps are rarely seen. Despite the low incidence of relevant manifestations described, controversies remain regarding the clinical significance of this condition. Case report: A 53-year-old man with heartburn and regurgitation was referred for management of a sessile polyp (Paris 0-Is) in the proximal esophagus, identified during an esophagogastroduodenoscopy. The patient's medical history includes heavy tobacco consumption. Additionally, he was taking esomeprazole at a dose of 40 mg. We repeated upper gastrointestinal endoscopy and observed two areas of pink mucosa in opposite position in the proximal esophagus, suggestive of gastric heterotopia. One of these areas had a polypoid morphology with congestive and friable mucosa, measuring approximately 12 mm. Narrow Band Imaging evaluation demonstrated a preserved glandular and vascular pattern. Anatomopathological assessment of the lesion revealed fragments of gastric-type mucosa, consisting of occasionally poorly oriented foveolar structures, compatible with ulcerated gastric heterotopia. A multidisciplinary approach led us to decide on an expectant strategy due to its probable benign course. Conclusion: Hyperplastic polyps rarely originate from esophageal inlet patches, and to our knowledge, only a few case reports of gastric heterotopia with polypoid morphology exist in the literature. Further research is needed to determine the most appropriate management for these patients.

Narrow band imaging in oral cancer did not improve visualisation of the tumour borders: a prospective cohort study

Background In oral cancers, tumour borders are typically defined by white light (WL). Narrow-band imaging (NBI) is an optical endoscopic technique commonly used for the larynx and for cancers of unknown primary. However, evidence for using NBI in oral cancers is insufficient. Aims/objectives We investigated whether NBI is a better predictor of the true mucosal tumour borders than WL in oral cancers. Additionally, we examined the agreement between NBI-based Takano intrapapillary capillary loop classifications and pathology reports. Materials and methods In this prospective study, the tumour borders were assessed by both NBI and WL at the time of surgical resection and then compared. Pathology reports of the examined areas were used as gold standard. Results Forty-nine participants were included. After exclusion of 15 patients due to missing data, 34 were included in analyses. In 26.5% of the assessments, the tumour borders defined by NBI were outside the borders defined by WL. However, 55.5% of these were false-positives. Conclusions and significance The delineation of mucosal tumour borders in oral cancers by NBI was not better than that by WL in this study. Several methodological challenges may have influenced the findings of this study, similar to the limitations reported in previous studies.

Results of CO2 laser surgery in laryngeal papillomatosis

Recurrent respiratory papillomatosis is medical condition strictly connected with HPV infection of the epithelium of the upper respiratory track. The main treatment of lesions located in larynx or lower pharynx includes microsurgical excision by using CO2 laser. A thorough preoperative assessment of patients is extremely important, which should not only be based on traditional laryngological examination, but also on endoscopy of the larynx and the use of the NBI (narrow band imaging) technique to assess the vascularization of lesions. In patients with recurrent papillomas, neoadjuvant therapy with antiviral agents or agents that inhibit angiogenesis is also often used. Among our group of 31 patients with laryngeal papillomas, 15 people (48%) required repeated surgical intervention and additional antiviral therapy while 10 (33%) people had to undergo the procedure three or more times due to disease recurrence. In this article we will discuss that laryngeal microsurgery with a CO2 laser is an effective method of treating patients with laryngeal papillomatosis and we will present the possibilities of adjuvant therapy.

JWST Observations of Young protoStars (JOYS)

Context. Due to the high visual extinction and lack of sensitive mid-infrared (MIR) telescopes, the origin and properties of outflows and jets from embedded Class 0 protostars are still poorly constrained. Aims. We aim to characterise the physical, kinematic, and dynamical properties of the HH 211 jet and outflow, one of the youngest protostellar flows. Methods. We used the James Webb Space Telescope (JWST) and its Mid-InfraRed Instrument (MIRI) in the 5–28 µm range to study the embedded HH 211 flow. We mapped a 0′.95 × 0′.22 region, covering the full extent of the blueshifted lobe, the central protostellar region, and a small portion of the redshifted lobe. We extracted spectra along the jet and outflow and constructed line and excitation maps of both atomic and molecular lines. Additional JWST NIRCam H2 narrow-band images (at 2.122 and 3.235 µm) provide a visualextinction map of the whole flow, and are used to deredden our data. Results. The jet-driving source is not detected even at the longest MIR wavelengths. The overall morphology of the flow consists of a highly collimated jet, which is mostly molecular (H2, HD) with an inner atomic ([Fe I], [Fe II], [S I], [Ni II]) structure. The jet shocks the ambient medium, producing several large bow shocks (BSs) that are rich in forbidden atomic ([Fe II], [S I], [Ni II], [Cl I], [Cl II], [Ar II], [Co II], [Ne II], [S III]) and molecular lines (H2, HD, CO, OH, H2O, CO2, HCO+), and is driving an H2 molecular outflow that is mostly traced by low- J, v = 0 transitions. Moreover, H2 0-0 S(1) uncollimated emission is also detected down to 2″-3″ (~650–1000 au) from the source, tracing a cold (T=200–400 K), less dense, and poorly collimated molecular wind. Two H2 components (warm, T =300–1000 K, and hot, T =1000–3500 K) are detected along the jet and outflow. The atomic jet ([Fe II] at 26 µm) is detected down to ~130 au from the source, whereas the lack of H2 emission (at 17 µm) close to the source is likely due to the large visual extinction (AV > 80 mag). Dust-continuum emission is detected at the terminal BSs and in the blue- and redshifted jet, and is likely attributable to dust lifted from the disc. Conclusions. The jet shows an onion-like structure, with layers of different size, velocity, temperature, and chemical composition. Moreover, moving from the inner jet to the outer BSs, different physical, kinematic, and excitation conditions for both molecular and atomic gas are observed. The mass-flux rate and momentum of the jet, as well as the momentum flux of the warm H2 component, are up to one order of magnitude higher than those inferred from the atomic jet component. Our findings indicate that the warm H2 red component is the main driver of the outflow, that is to say it is the most significant dynamical component of the jet, in contrast to jets from more evolved YSOs, where the atomic component is dominant.

Narrow-band imaging offers a shorter menstrual bleeding time and a longer remission for hysteroscopic surgery in symptomatic post-cesarean scar diverticulum compared to white light

Background Narrow-band imaging (NBI) is a novel endoscopic imaging technology that improves the visibility of capillaries. The aim of this study was to evaluate the efficacy of NBI hysteroscopic excision in symptomatic post-cesarean scar diverticulum (PCSD) patients compared to conventional white light (WL) hysteroscopy. Method A total of 73 patients with symptomatic PCSD between January 2014 and December 2018 were enrolled. The enrolled patients were stratified into NBI and WL groups according to whether they received NBI or WL hysteroscopy. Postoperative menstrual patterns at one, six, and 12 months after the operation were collected and compared between the NBI and WL groups. Results A total of 32 patients underwent NBI hysteroscopy (NBI group), while 41 patients received WL hysteroscopy (WL group). The symptom-free remission rates in the NBI group were significantly higher than in the WL group at six months and 12 months post-hysteroscopy. At the final follow-up, the menstrual bleeding duration in the NBI group was significantly shorter than in the WL group. Conclusion The use of NBI hysteroscopy in treating symptomatic PCSD resulted in shorter menstrual bleeding days and longer symptomatic remission compared to conventional WL hysteroscopy.

Umbral flashes and their association with running penumbral waves: a study using MAST Ca ii 8542 Å narrow-band observations

ABSTRACT Umbral flashes (UFs) are one of the most dynamic phenomena observed in the sunspot umbra at the chromospheric heights. In this paper, we present spectroscopic observations of UFs in the Ca ii 8542 Å line recorded by a narrow-band imager working with the Multi-Application Solar Telescope (MAST). The deduced data are analysed to obtain various properties of the UFs occuring at different locations inside the umbral boundary. An intensity enhancement of up to 30% or more was observed at the location of UFs, with a periodicity $\approx$3 min. The line-of-sight (LOS) velocity of UFs was estimated using bisector application to the emission profile resulting from the removal of mean umbral and the mean quiet Sun (QS) line profiles. The emission profiles resulting from removing the mean umbral profile were observed to better represent the emission component of the UF line profile. Both up-flows and down-flows of the order $\approx$5 km s$^{-1}$ were associated with the UFs with an average up-flow of $\approx$1 km s$^{-1}$. Out of all UFs analysed, 31% were observed to be associated with down-flows in case of removal of the mean umbral profile from the UF line profile. We observed multiple radially propagating LOS velocity disturbances ($\approx$20–40 km s$^{-1}$) in the penumbra, which might be associated with the UFs, even though we could not establish a one-to-one correspondence. The horizontally propagating LOS velocity disturbances could produce the visual effect of running penumbral waves, which produce intensity fluctuations in intensity images when observed at the line-centre wavelength. The simultaneous photospheric HMI observations showed no distinct intensity or velocity signatures corresponding to the UFs observed in the chromospheric Ca ii 8542 Å line.

Correlation between White Globe Appearance and Clinicopathologic Characteristics in Early Gastric Cancer.

Magnifying endoscopy with narrow-band imaging (ME-NBI) enables the visualization of detailed microsurface (MS) and microvascular (MV) structures in the gastrointestinal tract. White globe appearance (WGA) is a small whitish lesion with a globular shape identified during ME-NBI for early gastric cancer (EGC). This study aimed to investigate the associations between WGA, clinicopathological characteristics, and other ME-NBI findings in patients with EGC. The presence or absence of WGA in 122 patients (126 lesions) with an endoscopic diagnosis of EGC who underwent ME-NBI before endoscopic or surgical resection was prospectively collected and retrospectively analyzed. During ME-NBI, the MS and MV patterns and the presence of WGA and white opaque substances (WOS) were investigated. EGC cases were categorized as differentiated or undifferentiated type, and mucosal, submucosal, or advanced. Of 126 lesions, WGA was observed in 25 (19.8%). WGA was associated with tumor size (≤2 cm [17/63, 27.0%] vs >2 cm [8/63, 12.7%]; p=0.044), histologic type (differentiated type [22/89, 24.7%] vs undifferentiated type [3/37. 8.1%]; p=0.033), and tumor location (upper third [1/11, 9.1%] vs middle third [18/58, 31.0%] and lower third [6/57, 10.5%]; p=0.017). Although WGA was observed more frequently in lesions with an oval/tubular MS pattern, a fine-network MV pattern, and the absence of WOS, the difference was not statistically significant (MS pattern, p=0.358; MV pattern, p=0.212; WOS, p=0.121, respectively). WGA was associated with small tumor size, differentiated-type histology, and middle-third tumor location, and was more frequently observed in lesions with an oval/tubular MS and fine-network MV patterns and the absence of WOS.

Improving the accuracy of SIF quantified from moderate spectral resolution airborne hyperspectral imager using SCOPE: assessment with sub-nanometer imagery

Hyperspectral imaging of solar-induced chlorophyll fluorescence (SIF) is required for plant phenotyping and stress detection. However, the most accurate instruments for SIF quantification, such as sub-nanometer (≤1-nm full-width at half-maximum, FWHM) airborne hyperspectral imagers, are expensive and uncommon. Previous studies have demonstrated that standard narrow-band hyperspectral imagers (i.e., 4–6-nm FWHM) are more cost-effective and can provide far-red SIF quantified at 760 nm (SIF760), which correlates strongly with precise sub-nanometer resolution measurements. Nevertheless, narrow-band SIF760 quantifications are subject to systematic overestimation owing to the influence of the spectral resolution (SR). In this study, we propose a modelling approach based on the Soil Canopy Observation, Photochemistry and Energy Fluxes (SCOPE) model with the objective of enhancing the accuracy of absolute SIF760 levels derived from standard airborne hyperspectral imagers in practical settings. The performance of the proposed method was evaluated using airborne imagery acquired from two airborne hyperspectral imagers (FWHM ≤ 0.2-nm and 5.8-nm) flown in tandem on board an aircraft that collected data from two different wheat and maize phenotyping trials. Leaf biophysical and biochemical traits were first estimated from airborne narrow-band reflectance imagery and subsequently used as SCOPE model inputs to simulate a range of top-of-canopy (TOC) radiance and SIF spectra at 1-nm FWHM. The SCOPE simulated radiance spectra were then convolved to match the spectral configuration of the narrow-band imager to compute the 5.8-nm FWHM SIF760. A site-specific model was constructed by employing the convolved 5.8-nm SR SIF760 as the independent variable and the 1-nm SR SIF760 directly simulated by SCOPE as the dependent variable. When applied to the airborne dataset, the estimated SIF760 at 1-nm SR from the standard narrow-band hyperspectral imager matched the reference sub-nanometer quantified SIF760 with root mean square error (RMSE) less than 0.5 mW/m2/nm/sr, yielding R2 = 0.93–0.95 from the two experiments. These results suggest that the proposed modelling approach enables the interpretation of SIF760 quantified using standard hyperspectral imagers of 4–6 nm FWHM for stress detection and plant physiological condition assessment.

S3149 Lynch Syndrome Uncovered: Identifying Anastomotic Site Recurrence Through Narrow Band Imaging

S3149 Lynch Syndrome Uncovered: Identifying Anastomotic Site Recurrence Through Narrow Band Imaging

Spectrum aided vision enhancer enhances mucosal visualization by hyperspectral imaging in capsule endoscopy.

Narrow-band imaging (NBI) is more efficient in detecting early gastrointestinal cancer than white light imaging (WLI). NBI technology is available only in conventional endoscopy, but unavailable in magnetic-assisted capsule endoscopy (MACE) systems due to MACE's small size and obstacles in image processing issues. MACE is an easy, safe, and convenient tool for both patients and physicians to avoid the disadvantages of conventional endoscopy. Enabling NBI technology in MACE is mandatory. We developed a novel method to improve mucosal visualization using hyperspectral imaging (HSI) known as Spectrum Aided Visual Enhancer (SAVE, Transfer N,Hitspectra Intelligent Technology Co., Kaohsiung, Taiwan). The technique was developed by converting the WLI image captured by MACE to enhance SAVE images. The structural similarity index metric (SSIM) between the WLI MACE images and the enhanced SAVE images was 91%, while the entropy difference between the WLI MACE images and the enhanced SAVE images was only 0.47%. SAVE algorithm can identify the mucosal break on the esophagogastric junction in patients with gastroesophageal reflux disorder. We successfully developed a novel image-enhancing technique, SAVE, in the MACE system, showing close similarity to the NBI from the conventional endoscopy system. The future application of this novel technology in the MACE system can be promising.

Narrow band imaging: Important tool for early diagnosis, management, and improved outcomes in gastrointestinal lesions.

Narrow band imaging-magnifying endoscopy (NBI-ME) is used to identify changes in mucosal or vascular pattern observed on GI endoscopy in real time on the basis of optical image enhancement.It has a significant role in early detection of dysplasia, premalignant, and Malignant lesions along with its depth of invasion. Upper and lower GI endoscopy performed in 1742 patients who presented with gastrointestinal symptoms at this tertiary center over 5years out of which 1623 were evaluated with both NBI-ME and histopathology. Real time endoscopic assessment was performed. Targeted biopsies were taken for comparative analysis. Of the 1742 patients, 119 were excluded from the study. 807 underwent upper GI endoscopy and 816 underwent lower GI endoscopy. Mean age of presentation was 38 +/- 2.7years. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of NBI-ME for neoplastic esophageal lesions were 96.3%, 90.6%, 91.1%, 96.03%, respectively. For Barrett's esophagus it was 95.4%, 90.7%, 86.1%, and 90.7%; For gastric neoplastic lesions the values were 96.1%, 91.04%, 83.8%, and 97.9%. For colorectal it was 96.7%, 91.3%, 88.0%, and 97.7%. Overall sensitivity, specificity, PPV, andNPVof NBI-ME for neoplastic lesions (both upper and lower GI) were 96.2%, 91.0%, 96.2%, and 97.2%. Of the 1623 patients, 951 received medical management with regular surveillance and 672 patients with high-grade dysplasia, premalignant, and malignant conditions underwent interventions in form of either endoscopy or surgery. NBI-ME has a greater role and can be considered as an effective tool in making early diagnosis and guiding optimum treatment.

Endoscopic diagnosis of melanoma

Background. Although skin melanoma is a tumour which can be localised visually, its current diagnosis remains unsatisfactory. Skin melanoma exhibits an extremely diverse clinical presentation and a highly variable progression of the neoplastic process.Aim. To analyze our experience in diagnosing metastatic melanoma of the gastrointestinal tract.Materials and methods. The paper presents data from endoscopic and morphological studies of 29 patients who were diagnosed with metastatic melanoma with lesions of the gastrointestinal tract at the Department of Endoscopy the N. Blokhin National Medical Research Centre of Oncology.Results. Among the patients there were 12 (41.3 %) men and 17 (58.6 %) women, whose average age was 50 and 53 years, respectively, the majority of metastatic lesions of the gastrointestinal tract were asymptomatic, only 4 (13.8 %) patients had the disease accompanied by complaints such as difficulty passing food, in 2 cases (6.9 %) episodes of gastrointestinal bleeding were detected. In 7 (24.1 %) cases, the source of metastasis was not identified. The features of the manifestation of metastatic melanomas include the frequently combined lesions of the oesophagus, stomach and duodenum. In rare cases, there is a combination of pigmented and pigmented forms of melanoma.Conclusion. Given the high potential for regional metastasis, the ability of melanoma to disseminate through the skin, the occurrence of multiple metastases even in the absence of local growth, and its often asymptomatic progression in gastrointestinal organs, the diagnostic protocol should encompass the full spectrum of endoscopic techniques. This includes esophagogastroduodenoscopy and colonoscopy, utilizing advanced methods such as narrow-band imaging, magnification, or a combination of both. Biopsy samples should be taken for morphological, cytological, and immunological analysis. Additionally, comprehensive diagnostic methods such as immunoscopy should be employed.

Confocal laser endomicroscopy for gastric neoplasm.

Confocal laser endomicroscopy (CLE) is a novel endoscopic modality that provides real-time histological information via high-resolution magnified view of the mucosa. CLE has a higher sensitivity, specificity, and diagnostic accuracy in detecting atrophic gastritis as compared to chromoendoscopy and narrow-band imaging. It can even predict low-grade and high-grade intraepithelial neoplasia by analyzing gastric pit patterns. CLE may have some advantages over the standard biopsy protocol, such as higher diagnostic yield and fewer biopsy requirements. Its diagnostic accuracy in detecting superficial gastric cancer is higher than that of white-light endoscopy. Inherent limitations, such as a narrow field of vision, can be surpassed by technological advancements and integration with other detection methods. Artificial intelligence holds promise in automated analysis of histopathological images. Thus, CLE can be helpful in screening for early gastric cancer and may help reduce the risk of complications from repeated biopsies, such as mucosal damage, bleeding, and infection.

Endoscopic Evaluation and Management of Superficial Esophageal Squamous Cell Carcinoma

AbstractEsophageal squamous cell carcinoma (SCC) is the seventh most common malignancy and the sixth leading cause of cancer-related deaths globally, demanding precise diagnostic and individualized therapeutic interventions. This case study describes the diagnosis and treatment of esophageal SCC in a 54-year-old man initially detected during an upper gastrointestinal endoscopy. The lesion was identified using narrow-band imaging and magnifying endoscopy; after imaging studies, it was treated with endoscopic submucosal dissection (ESD). ESD is known for its minimal invasiveness and the definitive histopathological evaluation it facilitates.The management strategy described in this paper reiterates the criticality of extensive pretreatment evaluations, the indication of the application of ESD, and the importance of a multidisciplinary team. It underscores the significance of careful posttreatment monitoring and the informed selection of adjuvant therapies, particularly in areas like India, where such advanced endoscopic techniques are still on the rise.

Organ-preserving treatment for urothelial carcinoma of the upper urinary tract

Urothelial carcinoma of the upper urinary tract is rare but the incidence is currently increasing in western countries. Radical nephroureterectomy has long been the standard treatment; however, it can lead to chronic kidney failure and also the necessity for dialysis. Therefore, organ-preserving treatment is now recommended for selected patients with low-risk tumors. The choice of treatment depends on the tumor characteristics, comorbidities and individual risk factors. Surgical options for organ preservation include ureterorenoscopy (URS), percutaneous treatment and partial ureteral resection. The URS is the most frequently used method for organ preservation. Photodynamic diagnostics (PDD) and narrow band imaging (NBI) can potentially also be used for tumor detection in the upper urinary tract. Conservative options such as topical treatment with mitomycinC or Bacillus Calmette-Guérin (BCG) and systemic treatment options are also possible.

A novel color-aided system for diagnosis of early gastric cancer using magnifying endoscopy with narrow-band imaging.

The Pink Zone Pattern (PP) sign is a typical color alteration of early gastric cancer (EGC) under magnifying endoscopic narrow-band imaging (ME-NBI). By integrating the color changes (PP sign) with the "vessel plus surface (VS)" classification system, we developed an innovative diagnostic system for EGC and named it "Pink Microsurface Microvascular (PSV)" system. Here, we aimed to elucidate the diagnostic performance of the PSV system for EGC. We conducted a single-center prospective clinical study (before-after design) consisting of 2 cross-sectional studies at 2 separate periods. In the before phase, 184 suspected lesions were evaluated using the VS system under ME-NBI; in the after phase, 183 suspected lesions were evaluated using the PSV system. We compared the diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) between the VS group and the PSV group. The accuracy, sensitivity, specificity, PPV, and NPV of the VS system for EGC were 84.6%, 87.0%, 83.6%, 67.8%, and 94.2%, respectively, and those for the PSV system were 93.0%, 92.0%, 93.4%, 85.2%, and 96.6%, respectively. The accuracy, specificity, and PPV of the PSV system were superior to those of the VS system. However, the sensitivity and NPV did not significantly differ between the VS system and the PSV system. The VS system was inconclusive for 22 lesions (12.0%) and the PSV system was inconclusive for 11 lesions (6.0%). The PSV system could identify more suspicious lesions than the VS system. We propose a new PSV diagnostic system by combining the VS system and the PP sign. Compared with the VS system, the PSV system could identify more suspected lesions and improve the diagnostic performance of EGC.

435. PREVALENCE OF OESOPHAGEAL PREMALIGNANT LESIONS AMONG PATIENTS REFERRED FOR GASTRO-OESOPHAGEAL-DUODENOSCOPY AT A TERTIARY CARE HOSPITAL IN NORTHERN, SRI LANKA

Abstract Background Oesophageal cancer is the second leading cause of cancer-related mortality in Sri Lanka, where a higher prevalence is found among Tamil-speaking Sri Lankans. Endoscopic screening with Lugol’s chromo endoscopy in high-incidence populations reduces mortality from oesophageal cancer. The objective of this study is to determine the prevalence of premalignant oesophageal lesions - squamous dysplasia and Barrett’s oesophagus and the associated risk factors among Tamil patients undergoing oesophageal-gastro-duodenoscopy (OGD). Methods Consecutive patients undergoing OGD for dyspeptic and gastric acid reflux symptoms were recruited. An interviewer-administered questionnaire was used for data collection. During OGD, the oesophagus was examined under white light imaging, narrow band imaging (NBI), and Lugol’s iodine chromo endoscopy. Biopsies were taken from abnormal mucosa and sent for pathological diagnosis. Statistical software SPSS (V25) was used to analyse the data. Results The study incorporates 410 participants. The majority (61.7%) were females and the median age was 57 (Interquartile range 21) years. On Endoscopy under white light and NBI 11.0%(n=45) had squamous neoplasia. Of them, 16.0% had Low grade dysplasia (LGD), 2.0% had invasive carcinoma and the remaining 82.0% had inflammatory or reactive changes. Endoscopic Barrett’s oesophagus (BO) was found in 17.0% (n=69) and 5.0% (n=19) had both endoscopic and histological confirmation of BO. Of them, 21.0% had LGD. In regression analysis, male gender was at higher risk for BO (OR- 1.251, 95%CI 0.420 – 3.730). Overall, 3.0% of the participants had premalignant lesions. Conclusions The prevalence of premalignant lesions in a symptomatic population was only 3.0%. Further studies with a larger number of targeted population is needed to assess the exact prevalence.

Exploring vision transformers for classifying early Barrett's dysplasia in endoscopic images: A pilot study on white-light and narrow-band imaging.

Various deep learning models, based on convolutional neural network (CNN), have been shown to improve the detection of early esophageal neoplasia in Barrett's esophagus. Vision transformer (ViT), derived from natural language processing, has emerged as the new state-of-the-art for image recognition, outperforming predecessors such as CNN. This pilot study explores the use of ViT to classify the presence or absence of early esophageal neoplasia in endoscopic images of Barrett's esophagus. A BO dataset of 1918 images of Barrett's esophagus from 267 unique patients was used. The images were classified as dysplastic (D-BO) or non-dysplastic (ND-BO). A pretrained vision transformer model, ViTBase16, was used to develop our classifier models. Three ViT models were developed for comparison based on imaging modality: white-light imaging (WLI), narrow-band imaging (NBI), and combined modalities. Performance of each model was evaluated based on accuracy, sensitivity, specificity, confusion matrices, and receiver operating characteristic curves. The ViT models demonstrated the following performance: WLI-ViT (Accuracy: 92%, Sensitivity: 82%, Specificity: 95%), NBI-ViT (Accuracy: 99%, Sensitivity: 97%, Specificity: 99%), and combined modalities-ViT (Accuracy: 93%, Sensitivity: 87%, Specificity: 95%). Combined modalities-ViT showed greater accuracy (94% vs 90%) and sensitivity (80% vs 70%) compared with WLI-ViT when classifying WLI images on a subgroup testing set. ViT exhibited high accuracy in classifying the presence or absence of EON in endoscopic images of Barrett's esophagus. ViT has the potential to be widely applicable to other endoscopic diagnoses of gastrointestinal diseases.

CHANG-ES. XXXII. Spatially Resolved Thermal–Nonthermal Separation from Radio Data Alone—New Probes into NGC 3044 and NGC 5775

We have carried out spatially resolved thermal–nonthermal separation on two edge-on galaxies, NGC 3044 and NGC 5775, using only radio data. Narrowband imaging within a frequency band that is almost contiguous from 1.25 to 7.02 GHz (L band, S band, and C band) has allowed us to fit spectra and construct thermal, nonthermal, and nonthermal spectral index maps. This method does not require any ancillary Hα and IR data or rely on dust corrections that are challenging in edge-on galaxies. For NGC 3044, at 15″ resolution, we find a median thermal fraction of ∼13% with an estimated uncertainty in this fraction of ∼50% at 4.13 GHz. This compares well with the Hα mixture method results. We uncovered evidence for a vertical outflow feature reaching at least z ∼ 3.5 kpc in projection above the plane, reminiscent of M82's starburst wind. For the higher star formation rate galaxy, NGC 5775, at 12″ resolution, we find a median thermal fraction of 44% at 4.13 GHz with an estimated error on this fraction of 17%. Both galaxies show a change of slope (flattening) in L band. These results suggest that a radio-only method for separating thermal from nonthermal emission is not only feasible, but able to reveal new features that might otherwise be obscured in edge-on disks.

Resolving a Candidate Dual Active Galactic Nucleus with ∼100 pc Separation in MCG-03-34-64

We report the serendipitous multiwavelength discovery of a candidate dual black hole system with a separation of ∼100 pc, in the gas-rich luminous infrared galaxy MCG-03-34-64 (z = 0.016). Hubble Space Telescope/Advanced Camera for Surveys observations show three distinct optical centroids in the [O iii] narrow-band and F814W images. Subsequent analysis of Chandra/ACIS data shows two spatially resolved peaks of equal intensity in the neutral Fe Kα (6.2–6.6 keV) band, while high-resolution radio continuum observations with the Very Large Array at 8.46 GHz (3.6 cm band) show two spatially coincident radio peaks. Fast shocks as the ionizing source seem unlikely, given the energies required for the production of Fe Kα. If confirmed, the separation of ∼100 pc would represent the closest dual active galactic nuclei reported to date with spatially resolved, multiwavelength observations.