Efficacy of texture and color enhancement imaging for the visibility and diagnostic accuracy of non-polypoid colorectal lesions.

Objective: A newly launched endoscopy system (EVIS X1, CV-1500; Olympus) is equipped with texture and color enhancement imaging (TXI). We aimed to investigate the efficacy of TXI for the visibility and diagnostic accuracy of non-polypoid colorectal lesions. Methods: We examined 100 non-polypoid lesions in 42 patients from the same position, angle, and distance of the view in three modes: white light imaging (WLI), narrow-band imaging (NBI), and TXI. The primary outcome was to compare polyp visibility in the three modes using subjective polyp visibility score and objective color difference values. The secondary outcome was to compare the diagnostic accuracy without magnification. Results: Overall, the visibility score of TXI was significantly higher than that of WLI (3.7 ± 1.1 vs. 3.6 ± 1.1; p = 0.008) and lower than that of NBI (3.7 ± 1.1 vs. 3.8 ± 1.1; p = 0.013). Color difference values of TXI were higher than those of WLI (11.5 ± 6.9 vs. 9.1 ± 5.4; p < 0.001) and lower than those of NBI (11.5 ± 6.9 vs. 13.1 ± 7.7; p = 0.002). No significant differences in TXI and NBI (visibility score: 3.7 ± 1.0 vs. 3.8 ± 1.1; p = 0.833, color difference values: 11.6 ± 7.1 vs. 12.9 ± 8.3; p = 0.099) were observed for neoplastic lesions. Moreover, the diagnostic accuracy of TXI was significantly higher than that of NBI (65.5% vs. 57.6%, p = 0.012) for neoplastic lesions. Conclusions: TXI demonstrated higher visibility than that of WLI and lower than that of NBI. Further investigations are warranted to validate the performance of the TXI mode comprehensively.

Endoscopic detection and diagnosis of gastric cancer using image-enhanced endoscopy: A systematic review and meta-analysis.

Objectives: We aimed to conduct a systematic review and meta-analysis to assess the value of image-enhanced endoscopy including blue laser imaging (BLI), linked color imaging, narrow-band imaging (NBI), and texture and color enhancement imaging to detect and diagnose gastric cancer (GC) compared to that of white-light imaging (WLI). Methods: Studies meeting the inclusion criteria were identified through PubMed, Cochrane Library, and Japan Medical Abstracts Society databases searches. The pooled risk ratio for dichotomous variables was calculated using the random-effects model to assess the GC detection between WLI and image-enhanced endoscopy. A random-effects model was used to calculate the overall diagnostic performance of WLI and magnifying image-enhanced endoscopy for GC. Results: Sixteen studies met the inclusion criteria. The detection rate of GC was significantly improved in linked color imaging compared with that in WLI (risk ratio, 2.20; 95% confidence interval [CI], 1.39-3.25; p < 0.01) with mild heterogeneity. Magnifying endoscopy with NBI (ME-NBI) obtained a pooled sensitivity, specificity, and area under the summary receiver operating curve of 0.84 (95 % CI, 0.80-0.88), 0.96 (95 % CI, 0.94-0.97), and 0.92, respectively. Similarly, ME-BLI showed a pooled sensitivity, specificity, and area under the curve of 0.81 (95 % CI, 0.77-0.85), 0.85 (95 % CI, 0.82-0.88), and 0.95, respectively. The diagnostic efficacy of ME-NBI/BLI for GC was evidently high compared to that of WLI, However, significant heterogeneity among the NBI studies still existed. Conclusions: Our meta-analysis showed a high detection rate for linked color imaging and a high diagnostic performance of ME-NBI/BLI for GC compared to that with WLI.

Narrow-band imaging to enhance intraneural dissection in head and neck schwannoma surgery: a quantitative evaluation.

OBJECTIVE: The objective of this study was to assess the utility of narrow-band imaging (NBI) for improving intraneural dissection during gross total resection of head and neck schwannoma. Specifically, we aimed to quantitatively evaluate whether NBI can enhance the identification of pseudocapsule and true capsule within the tumor. METHODS: Nine schwannoma surgery cases conducted between February 2018 and October 2022 were retrospectively analyzed. The surgical procedures followed established principles with a specific focus on utilizing NBI to distinguish between the pseudocapsule and true capsule. Intraneural dissection was performed by searching for a tumor surface with a fascicle-free window, followed by longitudinal incision of the pseudocapsule. NBI was used to distinguish between the pseudocapsule and true capsule. Surgical views were captured under both white light (WL) illumination and NBI for further analysis. The brightness and contrast of the pseudocapsule and true capsule were quantitatively measured using ImageJ and were compared. RESULTS: Under NBI, the pseudocapsule consistently appeared greenish-gray, whereas the true capsule exhibited a white appearance. Quantitative analysis revealed a statistically significant difference (p < 0.0001) in brightness between the pseudocapsule (mean grayscale value 52.1, 95%CI; 46.4-75.3) and true tumor capsule (mean grayscale value 120.8, 95%CI; 155.7-109.0) under NBI. Conversely, there was no statistically significant difference in the brightness of these structures under WL (p = 0.2067). NBI also showed significantly higher contrast between the two structures than did WL (contrast 73.6, 95%CI; 53.1-89.5 vs. 30.9, 95%CI; 1.0-47.5, p = 0.0034). Further spectral analysis revealed that the most substantial difference in brightness between the pseudocapsule and the true tumor capsule was observed in the red spectrum, with a difference in brightness of -0.6 (95%CI; -16.8-14.8) under WL and 83.5 (95%CI; 50.3-100.0) under NBI (p < 0.0001). CONCLUSION: NBI proved to be a valuable tool for enhancing the identification of pseudocapsule and true capsule during intraneural dissection in head and neck schwannoma surgery. The improved contrast and membrane visibility offered by NBI might have the potential to reduce postoperative neurological deficits and improve surgical outcomes. Further research is warranted to validate our findings and explore the broader applications of NBI in schwannoma surgery.

Optimal Pathological Prediction of Vocal Fold Leukoplakia Based on IPCLs and Morphology.

OBJECTIVES: To establish a combined classification based on intrapapillary capillary loops (IPCLs) and morphological characteristics to improve the accuracy of pathological prediction of vocal fold leukoplakia (VFL). MATERIAL AND METHODS: A prospective research was conducted of VFL patients diagnosed by IPCLs and morphology. The VFL cases were classified as Type I-III based on IPCLs and morphological characteristics. Type I referred to VFL with dendritic vessels but not IPCLs. Type II defined VFL without any IPCLs or vessels and classified by morphology into two subtypes as non-rough Type IIa and rough Type IIb. Type III referred to VFL with IPCLs and classified into two subtypes as Type IIIa with small IPCLs and Type IIIb with large IPCLs or vascular distortion in or around lesions. Predicting pathology accuracy was analyzed. RESULTS: 182 eligible patients were recruited. The prediction accuracy rates of VFL pathology were 81.5% according to the 2019 Ni classification. The combined classification includes 4 cases of Type I, 28 Type IIa, 35 Type IIb, 56 Type IIIa, and 59 Type IIIb VFLs. The prediction accuracy rate of combined classification ranged from 95.1% to 97.3% in three observers. The average sensitivity, specificity, positive predictive value, negative predictive value was 97.8%, 86.2%, 97.4%, 88.2%, respectively. The inter-observer agreement varied from 84.1% to 94.0%, and mean area under curve of receiver-operating curve analysis was 0.954. CONCLUSIONS AND SIGNIFICANCE: The new combined classification based on IPCLs and morphological characteristics could predict pathology of VFL accurately. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

Endoscopic detection and diagnostic strategies for minute gastric cancer: A real-world observational study.

BACKGROUND: Minute gastric cancers (MGCs) have a favorable prognosis, but they are too small to be detected by endoscopy, with a maximum diameter ≤ 5 mm. AIM: To explore endoscopic detection and diagnostic strategies for MGCs. METHODS: This was a real-world observational study. The endoscopic and clinicopathological parameters of 191 MGCs between January 2015 and December 2022 were retrospectively analyzed. Endoscopic discoverable opportunity and typical neoplastic features were emphatically reviewed. RESULTS: All MGCs in our study were of a single pathological type, 97.38% (186/191) of which were differentiated-type tumors. White light endoscopy (WLE) detected 84.29% (161/191) of MGCs, and the most common morphology of MGCs found by WLE was protruding. Narrow-band imaging (NBI) secondary observation detected 14.14% (27/191) of MGCs, and the most common morphology of MGCs found by NBI was flat. Another three MGCs were detected by indigo carmine third observation. If a well-demarcated border lesion exhibited a typical neoplastic color, such as yellowish-red or whitish under WLE and brownish under NBI, MGCs should be diagnosed. The proportion with high diagnostic confidence by magnifying endoscopy with NBI (ME-NBI) was significantly higher than the proportion with low diagnostic confidence and the only visible groups (94.19% > 56.92% > 32.50%, P < 0.001). CONCLUSION: WLE combined with NBI and indigo carmine are helpful for detection of MGCs. A clear demarcation line combined with a typical neoplastic color using nonmagnifying observation is sufficient for diagnosis of MGCs. ME-NBI improves the endoscopic diagnostic confidence of MGCs.

Towards laryngeal cancer diagnosis using Dandelion Optimizer Algorithm with ensemble learning on biomedical throat region images.

Laryngeal cancer exhibits a notable global health burden, with later-stage detection contributing to a low mortality rate. Laryngeal cancer diagnosis on throat region images is a pivotal application of computer vision (CV) and medical image diagnoses in the medical sector. It includes detecting and analysing abnormal or cancerous tissue from the larynx, an integral part of the vocal and respiratory systems. The computer-aided system makes use of artificial intelligence (AI) through deep learning (DL) and machine learning (ML) models, including convolution neural networks (CNN), for automated disease diagnoses and detection. Various DL and ML approaches are executed to categorize the extraction feature as healthy and cancerous tissues. This article introduces an automated Laryngeal Cancer Diagnosis using the Dandelion Optimizer Algorithm with Ensemble Learning (LCD-DOAEL) method on Biomedical Throat Region Image. The LCD-DOAEL method aims to investigate the images of the throat region for the presence of laryngeal cancer. In the LCD-DOAEL method, the Gaussian filtering (GF) approach is applied to eliminate the noise in the biomedical images. Besides, the complex and intrinsic feature patterns can be extracted by the MobileNetv2 model. Meanwhile, the DOA model carries out the hyperparameter selection of MobileNetV2 architecture. Finally, the ensemble of three classifiers such as bidirectional long short-term memory (BiLSTM), regularized extreme learning machine (ELM), and backpropagation neural network (BPNN) models, are utilized for the classification process. A comprehensive set of simulations is conducted on the biomedical image dataset to highlight the efficient performance of the LCD-DOAEL technique. The comparison analysis of the LCD-DOAEL method exhibited a superior accuracy outcome of 97.54% over other existing techniques.

Clinical Value of Narrow Band Imaging Endoscopy in the Early Diagnosis and Staging Assessment of Laryngeal and Hypopharyngeal Cancer.

OBJECTIVE: To explore the clinical value of narrow band imaging (NBI) endoscopy in the early diagnosis and staging assessment of laryngeal and hypopharyngeal cancer. METHODS: A total of 78 patients with lesions in the hypopharynx or larynx were examined using endoscopy, observed under both white light and NBI modes, and graded using NBI. Using Lugol's iodine solution, laryngeal and hypopharyngeal lesions were graded using iodine staining. Using histopathological examination or postoperative pathological results as the diagnostic criteria, the sensitivity, specificity, and accuracy of endoscopy and iodine staining in diagnosing early cancer and precancerous lesions were evaluated. RESULTS: Multiple lesions were identified by both methods, and pathological examination confirmed 86 lesions, including early squamous cell carcinoma and precancerous lesions, such as early esophageal cancer, high-grade esophageal intraepithelial neoplasia, and hypopharyngeal cancer. Endoscopy showed significantly higher accuracy, detection rate, sensitivity, and specificity in NBI mode than in white light mode (96.12%, 86.05%, 97.37%, 86.67% vs 86.05%, 76.74%, 86.84%, 80%, respectively; P < 0.05). NBI grading and iodine staining grading showed good consistency with pathological diagnosis, with a Kappa value of 0.684 and 0.622, respectively. CONCLUSIONS: NBI endoscopy allows for better observation of subtle structural changes on the surface of lesions compared to white light endoscopy. It provides high accuracy in detecting early laryngeal and hypopharyngeal cancer and precancerous lesions, determining biopsy sites, facilitating early diagnosis, and establishing safe surgical margins. NBI endoscopy offers a viable alternative for non-invasive screening and early diagnosis of laryngeal and hypopharyngeal cancer, showing great potential for clinical advancement.

Tumor thickness as a novel risk factor for lymph node metastasis by superficial squamous cell carcinoma of head and neck.

Narrow-band imaging combined with magnified endoscopy has enabled the detection of superficial squamous cell carcinoma of the head and neck (SSCCHN) that has been resected with minimally invasive treatment, preserving vocalization and swallowing functions. However, risk factors of lymph node metastasis (LNM) must be identified, as some patients with LNM have a poor prognosis. From an initial 599 patients with 700 lesions who underwent trans-oral surgery in 27 Japanese hospitals (a nationwide registration survey), we enrolled 541 patients with 633 SSCCHNs, as indicated by central pathological diagnoses. All pathological specimens for each patient were examined using 20 pathological factors that are thought to affect the LNM of SSCCHN. In all, 24 (4.4%) of the 568 SSCCHNs exhibited LNM, and all 24 had at least one solitary nest of epithelial neoplastic cells present in the stroma, clearly separated from the intraepithelial carcinoma. Multivariate analysis also showed that tumor thickness (p = 0.0132, RR: 7.85, 95% confidence interval [CI]: 1.54-40.02), and an INFc pattern classified as infiltrating growth (INF) with unclear boundaries between tumor and non-tumor tissues (p = 0.0003, RR: 14.47, 3.46-60.46), and tumor budding (p = 0.0019, RR: 4.35, CI: 1.72-11.01) were significantly associated with LNM. Solitary nests may be indicative of LNM. In addition, tumor thickness was revealed to be a risk factor for LNM in SSCCHNs using pT factors that do not include an invasion depth element because of the anatomical absence of the muscularis mucosae.

Endoscopic Advances in the Diagnosis and Management of Gastroesophageal Reflux Disease.

Gastroesophageal reflux disease (GERD) is one of the most common diseases that occurs secondary to failure of the antireflux barrier system, resulting in the frequent and abnormal reflux of gastric contents to the esophagus. GERD is diagnosed in routine clinical practice based on the classic symptoms of heartburn and regurgitation. However, a subset of patients with atypical symptoms can pose challenges in diagnosing GERD. An esophagogastroduodenoscopy (EGD) is the most common initial diagnostic test used in the assessment for GERD, although half of these patients will not have any positive endoscopic findings suggestive of GERD. The advanced endoscopic techniques have improved the diagnostic yield of GERD diagnosis and its complications, such as Barrett's esophagus and early esophageal adenocarcinoma. These newer endoscopic tools can better detect subtle irregularities in the mucosa and vascular structures. The management options for GERD include lifestyle modifications, pharmacological therapy, and endoscopic and surgical interventions. The latest addition to the armamentarium is the minimally invasive endoscopic interventions in carefully selected patients, including the electrical stimulation of the LES, Antireflux mucosectomy, Radiofrequency therapy, Transoral Incisionless Fundoplication, Endoscopic Full-Thickness plication (GERDx™), and suturing devices. With the emergence of these advanced endoscopic techniques, it is crucial to understand their selection criteria, advantages, and disadvantages.

[The effect of narrow band imaging in CO2 laser therapy in early-stage glottic cancer].

Objective:To explore efficacy of narrow band imaging（NBI） technique in CO2laser therapy in Early-Stage Glottic cancer. Methods:The clinical data of patients with Early-Stage Glottic cancer who underwent CO2laser vocal cord resection from June 2011 to August 2022 were retrospectively analyzed. Among these, 27 patients who underwent surgery assisted by NBI were assigned to the observation group, while 25 patients who underwent conventional CO2 laser microsurgery with a suspension laryngoscope were assigned to the control group. The differences between the two groups were analyzed in terms of intraoperative frozen pathology results, postoperative recurrence rates, 5-year cumulative disease-free survival rates, complications, and voice recovery. Results:All 52 patients were operated successfully. Temporary tracheostomy and serious complications did not occur during the operation. The postoperative patient's pronunciation was satisfactory. One patient experienced vocal cord adhesion, but there were no severe complications such as breathing difficulties or bleeding, with an overall complication rate of 1.92%. Postoperative follow-up was 1-5 years. The 5 years recurrence free survival in the general group was 77.90％, and the 5 years recurrence free survival in the NBI group was 100％, the difference was statistically significant（P<0.05）. NBI endoscopy is safer and more accurate than the general group in determining the safe margin of tumor mucosal resection（P<0.05）. Among the patients who accepted the voice analysis, the difference was no statistically significant（P>0.05）. Conclusion:Compared with conventional CO2laser surgery under microscope, NBI guided laser resection of Early-Stage Glottic cancer is more accurate. NBI guided laser resection could improve 5 years recurrence free survival rate. In a word, narrow-band imaging endoscopy can has very high value in clinical application.

Design and Evaluation of ScanCap: A Low-Cost, Reusable Tethered Capsule Endoscope with Blue-Green Illumination Imaging for Unsedated Screening and Early Detection of Barrett's Esophagus.

Esophageal carcinoma is the sixth-leading cause of cancer death worldwide. A precursor to esophageal adenocarcinoma (EAC) is Barrett's Esophagus (BE). Early-stage diagnosis and treatment of esophageal neoplasia (Barrett's with high-grade dysplasia/intramucosal cancer) increase the five-year survival rate from 10% to 98%. BE is a global challenge; however, current endoscopes for early BE detection are costly and require extensive infrastructure for patient examination and sedation. We describe the design and evaluation of the first prototype of ScanCap, a high-resolution optical endoscopy system with a reusable, low-cost tethered capsule, designed to provide high-definition, blue-green illumination imaging for the early detection of BE in unsedated patients. The tethered capsule (12.8 mm diameter, 35.5 mm length) contains a color camera and rotating mirror and is designed to be swallowed; images are collected as the capsule is retracted manually via the tether. The tether provides electrical power and illumination at wavelengths of 415 nm and 565 nm and transmits data from the camera to a tablet. The ScanCap prototype capsule was used to image the oral mucosa in normal volunteers and ex vivo esophageal resections; images were compared to those obtained using an Olympus CV-180 endoscope. Images of superficial capillaries in intact oral mucosa were clearly visible in ScanCap images. Diagnostically relevant features of BE, including irregular Z-lines, distorted mucosa, and dilated vasculature, were clearly visible in ScanCap images of ex vivo esophageal specimens.

Automatic lesion detection for narrow-band imaging bronchoscopy.

Purpose: Early detection of cancer is crucial for lung cancer patients, as it determines disease prognosis. Lung cancer typically starts as bronchial lesions along the airway walls. Recent research has indicated that narrow-band imaging (NBI) bronchoscopy enables more effective bronchial lesion detection than other bronchoscopic modalities. Unfortunately, NBI video can be hard to interpret because physicians currently are forced to perform a time-consuming subjective visual search to detect bronchial lesions in a long airway-exam video. As a result, NBI bronchoscopy is not regularly used in practice. To alleviate this problem, we propose an automatic two-stage real-time method for bronchial lesion detection in NBI video and perform a first-of-its-kind pilot study of the method using NBI airway exam video collected at our institution. Approach: Given a patient's NBI video, the first method stage entails a deep-learning-based object detection network coupled with a multiframe abnormality measure to locate candidate lesions on each video frame. The second method stage then draws upon a Siamese network and a Kalman filter to track candidate lesions over multiple frames to arrive at final lesion decisions. Results: Tests drawing on 23 patient NBI airway exam videos indicate that the method can process an incoming video stream at a real-time frame rate, thereby making the method viable for real-time inspection during a live bronchoscopic airway exam. Furthermore, our studies showed a 93% sensitivity and 86% specificity for lesion detection; this compares favorably to a sensitivity and specificity of 80% and 84% achieved over a series of recent pooled clinical studies using the current time-consuming subjective clinical approach. Conclusion: The method shows potential for robust lesion detection in NBI video at a real-time frame rate. Therefore, it could help enable more common use of NBI bronchoscopy for bronchial lesion detection.

New Horizons and Prospects in Oral Cancer Detection.

Recent advancements in oral cancer detection prioritize non-invasive and minimally invasive techniques for efficient and accurate screening. This review outlines progress in methods such as narrow band imaging, fluorescence imaging, and optical coherence tomography, showing promise in early lesion detection. Biomarker detection in saliva and targeted nanoparticles enhance early diagnosis, while machine learning improves diagnostic accuracy. However, clinical validation and large-scale studies are needed for widespread adoption.

Standard-definition White-light, High-definition White-light versus Narrow-band Imaging Endoscopy for Detecting Colorectal Adenomas: A Multicenter Randomized Controlled Trial.

OBJECTIVE: This study aimed to compare the performance of standard-definition white-light endoscopy (SD-WL), high-definition white-light endoscopy (HD-WL), and high-definition narrow-band imaging (HD-NBI) in detecting colorectal lesions in the Chinese population. METHODS: This was a multicenter, single-blind, randomized, controlled trial with a non-inferiority design. Patients undergoing endoscopy for physical examination, screening, and surveillance were enrolled from July 2017 to December 2020. The primary outcome measure was the adenoma detection rate (ADR), defined as the proportion of patients with at least one adenoma detected. The associated factors for detecting adenomas were assessed using univariate and multivariate logistic regression. RESULTS: Out of 653 eligible patients enrolled, data from 596 patients were analyzed. The ADRs were 34.5% in the SD-WL group, 33.5% in the HD-WL group, and 37.5% in the HD-NBI group (P=0.72). The advanced neoplasm detection rates (ANDRs) in the three arms were 17.1%, 15.5%, and 10.4% (P=0.17). No significant differences were found between the SD group and HD group regarding ADR or ANDR (ADR: 34.5% vs. 35.6%, P=0.79; ANDR: 17.1% vs. 13.0%, P=0.16, respectively). Similar results were observed between the HD-WL group and HD-NBI group (ADR: 33.5% vs. 37.7%, P=0.45; ANDR: 15.5% vs. 10.4%, P=0.18, respectively). In the univariate and multivariate logistic regression analyses, neither HD-WL nor HD-NBI led to a significant difference in overall adenoma detection compared to SD-WL (HD-WL: OR 0.91, P=0.69; HD-NBI: OR 1.15, P=0.80). CONCLUSION: HD-NBI and HD-WL are comparable to SD-WL for overall adenoma detection among Chinese outpatients. It can be concluded that HD-NBI or HD-WL is not superior to SD-WL, but more effective instruction may be needed to guide the selection of different endoscopic methods in the future. Our study's conclusions may aid in the efficient allocation and utilization of limited colonoscopy resources, especially advanced imaging technologies.

Objective Comparison of White Light and Narrow-Band Imaging for Detecting Scars, Sulci and Nodules.

INTRODUCTION: Narrow-band imaging (NBI) can improve detection of lesions in the aerodigestive tract. However, its role in benign lesions of the larynx is unclear. This study aims to determine whether NBI improves the detection of scars, sulci, and nodules compared to panchromatic lighting using objective image analysis. METHODS: In total, 120 vocal folds (VFs) were analyzed with and without NBI (21 normal, 15 scars, 16 sulci, and 45 nodules). Each VF image had anterior, middle, and posterior thirds analyzed for brightness using an area morphometry software (Optimas 5.1a). The middle-third with the lesion was analyzed against surrounding VF segments for average and standard deviation (SD) in absolute grayscale. RESULTS: The use of panchromatic light resulted in greater illumination and grayscale values than NBI. All lesions tended to be in the mid-membranous fold. Under panchromatic light, change in brightness when comparing anterior versus middle (A-M) was +6.1% for normal, versus 6.5%, 8.1%, and 7.1% for sulci, nodules, and scars, respectively. Under NBI, they were 9.0% (normal), 12.3% (sulci), 13.7% (nodules), and 13.1% (scars). A greater SD of luminescence was observed at pathology sites (p < 0.05) when using NBI. The change in absolute grayscale at all lesion sites was greater when using NBI than when using panchromatic light (p < 0.05). CONCLUSION: NBI significantly enhanced the area of pathology in patients with nodules, sulci, and scars. Greater SD values in grayscale at pathologic sites were observed compared at normal sites. Thus, NBI may improve the detection of phonotraumatic lesions compared to panchromatic light. LEVEL OF EVIDENCE: N/A Laryngoscope, 134:4066-4070, 2024.

Association between colonic adenoma size and proliferative zone in the crypt.

BACKGROUND: We previously reported unusual adenomas with proliferative zones confined to the lower two-thirds of the crypt. The proliferative zones of colorectal adenomas have three patterns: 'lower,' 'superficial' and 'entire'. This study aimed to clarify the characteristics of each adenoma pattern. METHODS: We investigated 2925 consecutive patients who underwent colonoscopy at our institute. All polyps that were removed were histologically examined using hematoxylin and eosin staining. The location of the proliferative zone was assessed for adenomas. Data were compared using Dunn's and Kruskal-Wallis tests. RESULTS: Colorectal adenomas with 'lower' proliferative zone often appeared similar to hyperplastic polyps (42.8%), and the frequency was significantly higher than that of adenomas with 'superficial' and 'entire' proliferative zones (p < 0.001). The mean sizes of adenomas were 2.4, 3.0 and 3.9 mm for 'lower,' 'superficial' and 'entire' proliferative zones, respectively. A significant gradual increase was observed. Regarding morphology, the proportion of type 0-I in adenomas with an 'entire' proliferative zone was significantly higher than that in adenomas with 'superficial' proliferative zone (p < 0.001). CONCLUSION: While colorectal adenomas develop and increase in size, the proliferative zone appears to shift upward and become scattered.

Squamous cell papilloma of the hypopharynx with elongated villous projections.

Squamous cell papilloma with elongated villous projections may occur in the hypopharynx and present with symptoms observable on physical examination.

Extracapsular Dissection With Narrow-Band Imaging Using the Transnasal Endoscopic Tri-port Approach for Extracranial Trigeminal Schwannoma: A Case Report.

The pterygopalatine fossa and infratemporal fossa are often approached through an external incision because of their deep facial location, but this can present problems such as facial scarring and deformity. In schwannoma surgery, intraneural dissection is a useful surgical technique for achieving gross total resection while preserving the capsule, including the nerves. For appropriate enucleation and preservation of the functional nerve, it is indispensable to distinguish between the pseudocapsule and the tumor capsule. This case report presents a case of endonasal surgical intervention for an extracranial trigeminal schwannoma employing the tri-port approach and narrow-band imaging.

The Potential of Narrow-Band Imaging as a Novel Light Source for Photodynamic Therapy for Superficial Cancers via Endoscopes.

Background: Photodynamic therapy (PDT) has advanced through the utilization of photosensitizers and specific-wavelength light (≥ 600 nm). However, the widespread adoption of PDT is still impeded by high equipment costs and stringent laser safety requirements. Porphyrins, crucial in PDT, have another absorbance peak of blue light (λ = 380 - 500 nm). This peak corresponds to the wavelength of narrow-band imaging (NBI) (λ = 390 - 445 nm), an image-enhancement technology integrated into endoscopes by Olympus Medical Systems. The study aimed to investigate the potential of widely adopted NBI as a PDT light source for superficial cancers via endoscopes. Methods: Esophageal and biliary cancers were selected for investigation. Human esophageal cancer cell lines (KYSE30, KYSE70, KYSE170) and cholangiocarcinoma cell lines (HuCCT-1, KKU-213) were subjected to verteporfin-mediated PDT under NBI light (λ = 390 - 445 nm). Assessments included spectrometry, crystal violet staining, and fluorescein imaging of singlet oxygen generation and apoptosis. Results: Verteporfin exhibited a peak (λ = 436 nm) consistent with the NBI spectrum, suggesting compatibility with NBI light. NBI light significantly inhibited the growth of esophageal and biliary cancer cells. The half-maximum effective concentration (EC50) values (5 J/cm2) for KYSE30, KYSE70, KYSE170, HuCCT-1, and KKU-213 were calculated as 2.78 ± 0.37µM, 1.76 ± 1.20 µM, 0.77 ± 0.16 µM, 0.65 ± 0.18 µM, and 0.32 ± 0.04 µM, respectively. Verteporfin accumulation in mitochondria, coupled with singlet oxygen generation and observed apoptotic changes, suggests effective PDT under NBI light. Conclusions: NBI is a promising PDT light source for superficial cancers via endoscopes.

Implementing narrow banding imaging with dual focus magnification for histological prediction of small rectosigmoid polyps in Vietnamese setting.

Background and Aim: Small rectosigmoid colorectal polyps (<10 mm) are prevalent, with a low prevalence of advanced neoplastic lesions. The "diagnose-and-leave" strategy, employing narrow band imaging (NBI), is gaining popularity for its safety and cost-effectiveness by reducing polypectomy complications and minimizing histopathology expenses. This study assessed the diagnostic efficacy of NBI with dual focus (DF) magnification for real-time neoplastic prediction of rectosigmoid polyps and explored the feasibility of implementing this strategy in Vietnam. Methods: In a prospective single-center study, 307 rectosigmoid polyps from 245 patients were analyzed using three consecutive endoscopic modes: white light endoscopy (WLE), NBI, and NBI-DF. Endoscopists assessed polyps for size, location, macroscopic shape, optical diagnosis, and confidence levels before histopathological evaluation. High confidence was assigned when the polyp exhibited all features of a single histology type. Predictions were compared with final histopathology results. Results: Of the total, 237 (77.2%) were diminutive (≤5 mm) polyps, and 18 (5.8%) were advanced neoplastic lesions. WLE + NBI and WLE + NBI + NBI-DF exhibited significantly higher accuracy compared to WLE (88.6% and 90.2% vs 74.2%, P < 0.01). For diminutive polyps, the DF mode significantly increased the rate of high-confidence optical diagnoses (89.1% vs 94.9%, P < 0.001). WLE + NBI + NBI-DF demonstrated high sensitivity (90.1%), specificity (95.5%), and negative predictive value (93.4%) in high-confidence predictions, enabling the implementation of the "diagnose-and-leave" strategy. This approach would have reduced 58.2% of unnecessary polypectomies without missing any advanced neoplastic lesions. Conclusion: NBI and DF modes provide accurate neoplastic predictions for rectosigmoid polyps. For diminutive polyps, DF magnification improves the confidence level of the optical diagnosis, allowing the safe implementation of the "diagnose-and-leave" strategy.