Endoscopic Data Research Articles

Matrix gla protein, a potential marker of tissue remodelling and physiological ageing of the gut in crohn’s disease

Background The inactive dephosphorylated and uncarboxylated form of the matrix Gla protein (dp-ucMGP) has been shown to be increased in plasma of inflammatory bowel disease (IBD) patients. Our aim was to assess if the plasmatic level of dp-ucMGP could reflect disease endoscopic activity, presence of strictures and cumulative structural bowel damage in Crohn’s disease (CD) patients. Methods The plasmatic level of dp-ucMGP was measured in a monocentric cohort of prospectively recruited patients. The analysis was done by chemiluminescent immunoassay on blood samples collected the day of a planned ileocolonoscopy. In addition to classical clinical data (gender, age, body mass index (BMI), disease duration, current treatment), endoscopic data (disease location, Crohn’s Disease Endoscopic Index of Severity (CDEIS), mucosal healing (MH), presence of 9 CD lesion types) and biological markers (faecal calprotectin and C-reactive protein (CRP)) were collected. The association between dp-ucMGP level and Lémann index was also investigated. Univariate linear regression was used to investigate the relationship between dp-ucMGP level and different parameters collected. Results A total of 82 ileocolonoscopies and dp-ucMGP assays were performed in 75 CD patients (45 females; 37 ileocolonic, 19 ileal and 19 colonic diseases) between October 2012 and November 2019. A total of 24 patients (29.3%) showed MH. The dp-ucMGP levels were not associated with MH, CDEIS, faecal calprotectin or CRP levels. Plasmatic dp-ucMGP levels increased significantly with age (p = 0.0032), disease duration (p = 0.0033), corticosteroids use (p = 0.019) and tended to increase in patients with intestinal strictures (p = 0.086) but not with the Lémann index. Conclusion The significant increase of plasmatic dp-ucMGP levels with age, disease duration and the trend observed in patients with non-ulcerated strictures may suggest that this extracellular matrix protein could be a marker of tissue remodelling and physiological ageing of the gut.

Non-specific Colitis: An Endoscopist-Pathologist Miscommunication

Pathologists commonly report non-specific colitis (NSC) in the pathology reports of colon biopsies when they fail to characterize features of the colonic inflammation and diagnose the disease based on specific forms of colitis. Several conditions, ranging from irritable bowel syndrome, diverticular disease, celiac disease, to other systemic diseases have been proposed to be associated with the reporting of NSC in the colon pathology reports. Specifically, NSC could be a preceding pathological condition associated with these diseases before their symptoms and signs become more apparent. Based on a few studies, NSC may not be a particular disease, but rather a transient presentation of inflammatory bowel disease. This gist of this mini-review article is the failure of sharing demographic, clinical, laboratory, and endoscopic data between endoscopist and pathologist are the most important underlying cause of failed characterization of colitis by pathologists. Therefore, enhancement of endoscopist-pathologist ommunication would reduce the incidence of this misnomer and indirectly improve the diagnosis that helps with more accurate treatment.

Significant Reduction in the Diagnosis of Barrett's Esophagus and Related Dysplasia During the COVID-19 Pandemic.

The coronavirus disease 19 (COVID-19) pandemic disrupted endoscopy practices, creating unprecedented decreases in cancer screening and surveillance services. We aimed to assess the impact of the pandemic on the proportion of patients diagnosed with Barrett's esophagus (BE) and BE-related dysplasia and adherence to established quality indicators. Data from all esophagogastroduodenoscopies in the GI Quality Improvement Consortium, a national repository of matched endoscopy and pathology data, were analyzed from January 2018 to December 2022. Four cohorts were created based on procedure date and COVID-19 data: pre-pandemic (January 2018 to February 2020), pandemic-phase I (March 2020 to July 2020), pandemic-phase II (August 2020 to May 2021), and pandemic-phase III (June 2021 to December 2022). Observed and expected number of BE and BE-related dysplasia cases per month and adherence to the Seattle biopsy protocol and recommended surveillance intervals for nondysplastic BE (NDBE) were evaluated. Among 2,446,857 esophagogastroduodenoscopies performed during the study period, 104,124 (4.3%) had pathology-confirmed BE. The histologic distribution was 87.4% NDBE, 1.8% low-grade dysplasia, 2.4% indefinite for dysplasia, and 1.4% high-grade dysplasia. The number of monthly BE (-47.9% pandemic-phase I, -21.5% pandemic-phase II, and -19.0% pandemic-phase III) and BE-related dysplasia (high-grade dysplasia: 41.2%, -27.7%, and -19.0%; low-grade dysplasia: 49.1%, -35.3%, and -26.5%; any dysplasia: 46.7%, -32.3%, and -27.9%) diagnoses were significantly reduced during the pandemic phases compared with pre-pandemic data. Adherence rates to the Seattle protocol and recommended surveillance intervals for NDBE did not decline during the pandemic. There was a significant decline in the number of BE and BE-related dysplasia diagnoses during the COVID-19 pandemic, with an approximately 50% reduction in the number of cases of dysplasia diagnosed in the early pandemic. The absence of a compensatory increase in diagnoses in the pandemic-phase II and III periods may result in deleterious downstream effects on esophageal adenocarcinoma morbidity and mortality.

AUGMENTED REALITY-BASED NASAL ENDOSCOPE VIDEO RECONSTRUCTION AND REGISTRATION

Neuroendoscopic surgery is a minimally invasive surgical technique commonly used to remove a tumor through the patient’s mouth or nose, which requires the surgeon to avoid important neural and vascular structures. Augmented reality-based surgical navigation can provide surgeons with more information and visual aids, clarifying the structure and details of the surgical area. It requires real-time registration of intraoperative endoscopic video with pre-operative CT models. However, 3D reconstruction and camera tracking from nasal endoscopic video are challenging due to the narrow nasal cavity and the lack of texture. Besides, the nasal endoscopic datasets that can be used for deep learning-based depth estimation are scarce and hard to elaborate. To this end, a style-augmented module (SAM) is proposed in this study to minimize discrepancies between different endoscopic datasets. An unsupervised approach was trained to generate depth maps and camera motion paths, which were used to reconstruct the nasal scene’s 3D model. The obtained reconstruction was aligned with a pre-operative CT model for augmented reality-based surgical navigation. The results showed that the proposed SAM improved the generalization of the depth estimation model on nasal endoscopy data. The proposed approach to combining augmented reality technology with surgical navigation is considered instrumental in furnishing surgeons with richer information on the nasal endoscopic surgical scene.

Evaluation of Narrow-band Imaging of Early Gastric Cancer

The purpose of the study was to conduct a comparative assessment of endoscopic data obtained in a narrow-band imaging (NBI), according to the classification of H. Inoue, S. Kudo. In the conditions of the National Center of Oncology and Hematology, 1480 people were examined in the endoscopy department. The classification gives a clear definition of the proliferative processes of the gastric mucosa. A detailed description is provided.

The Diagnostic Yield of Upper GI Endoscopy in Patients Iron Deficiency Anemia and/or Chronic Diarrhea; With a Special Focus on Celiac Disease

Aim of the Study: According to published guidelines, an upper Gastrointestinal (GI) endoscopy with duodenal biopsy sampling should be performed in patients with Iron Deficiency Anemia (IDA) and/or chronic diarrhea. The cost-effectiveness of this strategy in the absence of obvious endoscopic reason explaining patients symptoms has not been thoroughly investigated. Aim of our study was to access the clinical benefit of such a strategy. Patients-Methods: All patients who underwent an upper GI endoscopy in our department due to IDA and/or chronic diarrhea during a 5-year period (1/2015-12/2019) were included in our study. Epidemiological, endoscopic and histologic data were analyzed. Results: The indication for endoscopy was IDA in 350 and chronic diarrhea in 108 patients; histological reports were available in 311 and 100 patients, respectively. Visual abnormalities were observed in 157 patients (34.3% in total; IDA: 32.9%, chronic diarrhea: 38.9%) and were more frequent among males than females (44.6% vs 33.5%, p=0.019) and among older patients (mean age 60 vs 56 years old, p=0.006). The histology report provided a conclusive diagnosis in 71/413 patients (17.2% in total; IDA: 14.8 %, chronic diarrhea: 25%). Celiac Disease (CD) was diagnosed in 7.5% of our total study group. Normal endoscopic appearance of the duodenum was observed in 33% of patients, while bulb atrophy was associated more frequently with a conclusive histological report compared to other or no endoscopic findings (23/63 or 36.5% vs 48/350 or 13,7%, p<0,001). Conclusions: Duodenal biopsy can aid significantly in the diagnosis of IDA or chronic diarrhea, even among patients without endoscopical abnormalities. Duodenal atroph

Endoscopic transaqueductal stent placement for tumor-related aqueductal compression in pediatric patients: surgical consideration, technique, and results

PurposeEndoscopic transaqueductal stenting has become a well-accepted treatment option for a selected small subset of aqueductal stenosis-related obstructive hydrocephalus. However, transaqueductal stenting poses unique challenges and risks which requires critical consideration. This report discusses the clinical experiences with transaqueductal stenting for periaqueductal tumor-related aqueductal stenosis focusing on pediatric patients.MethodsA retrospective analysis of all patients undergoing endoscopic TAS from 01/1993 to 01/2022 in the author’s departments was performed. Demographic, clinical, radiological, and intraoperative endoscopic data were evaluated. All patients with AS-related occlusive hydrocephalus that was treated with TAS were analyzed and prospectively followed. Special attention has been given to providing insights into indications, surgical technique, and limitations.ResultsOut of 28 endoscopic transaqueductal endoscopis stenting procedures, five procedures were performed on periaqueductal tumor-related obstructive hydrocephalus, two children and three adult patients. CSF pathway was obstructed by tumor located in the aqueduct in 2, by tumor in the thalamus/mesencephalon in 1, by a tumor within the third ventricle in 1, and by a tumor of the lamina tecti in 1. Simultaneously with transaqueductal stenting, 2 endoscopic third ventriculostomies (ETV), 3 tumor biopsies, and 1 tumor resection were performed. Postoperative complications included the following: CSF fistula (1 case), and asymptomatic fornix contusion (1 case). A working aqueductal stent was achieved in all cases based on clinical follow-up evaluation. Postoperatively, all patients showed improvement or resolution of their symptoms. The mean follow-up period was 25.2 months (range, 1–108 months). One patient died due to tumor progression during early follow-up. No stent migration was seen.ConclusionEndoscopic third ventriculostomy remains the gold standard for treatment of CSF circulation obstructions with lesions in the posterior third ventricle and aqueduct. Transaqueductal stenting for periaqueductal tumor-related aqueductal compression is technically feasible. However, because of the potential high risks and subtle advantages compared with ETV transaqueductal stenting, it might be indicated in a small subset of well-selected patients if alternative treatment options are not at hand.

De Novo Crohn's Disease in Children With Ulcerative Colitis Undergoing Ileal Pouch-Anal Anastomosis: A Multicenter, Retrospective Study From the Pediatric IBD Porto Group of the ESPGHAN.

We sought to define the prevalence and to characterize possible predictive factors of Crohn's disease (CD) occurring in children with ulcerative colitis (UC) after ileal pouch-anal anastomosis (IPAA). This was a multicenter, retrospective study including 15 centers of the Porto IBD group of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition. Children with a confirmed diagnosis of UC undergoing colectomy with IPAA and a minimal follow up of 6 months were identified. The following data were collected: demographic data; endoscopic and histologic data; disease activity; laboratory exams; therapeutic history; indication for surgery, type, and timing; and IPAA functional outcomes and complications. In de novo CD cases, time of diagnosis, phenotype, location, and therapies were gathered. We identified 111 UC children undergoing IPAA from January 2008 to June 2018 (median age at colectomy: 13 years; age range: 1-18 years; female/male: 59/52). The median time from diagnosis to colectomy was 16 (range, 0-202) months. At the last follow-up, 40 (36%) of 111 children developed pouchitis. The criteria for de novo CD were met in 19(17.1%) of 111 children with a 25-month median (range, 3-61 months). At last follow-up, 12 (63.1%) of 19 were treated with biologics and in 5 (26.3%) of 19 children, the pouch was replaced with definitive ileostomy. In a multivariable logistic regression model, decreased preoperative body mass index z scores (odds ratio, 2.2; 95% confidence interval, 1.1-4.4; P = .01) resulted as the only variable associated with CD development. Children with UC undergoing IPAA carry a high risk of developing subsequent CD. De novo CD cases showed decreased preoperative body mass index z scores, identifying a poor nutritional status as a possible predictive factor.

A Temporal Learning Approach to Inpainting Endoscopic Specularities and Its Effect on Image Correspondence

Video streams are utilised to guide minimally-invasive surgery and diagnosis in a wide range of procedures, and many computer-assisted techniques have been developed to automatically analyse them. These approaches can provide additional information to the surgeon such as lesion detection, instrument navigation, or anatomy 3D shape modelling. However, the necessary image features to recognise these patterns are not always reliably detected due to the presence of irregular light patterns such as specular highlight reflections. In this paper, we aim at removing specular highlights from endoscopic videos using machine learning. We propose using a temporal generative adversarial network (GAN) to inpaint the hidden anatomy under specularities, inferring its appearance spatially and from neighbouring frames, where they are not present in the same location. This is achieved using in-vivo data from gastric endoscopy (Hyper Kvasir) in a fully unsupervised manner that relies on the automatic detection of specular highlights. System evaluations show significant improvements to other methods through direct comparison and ablation studies that depict the importance of the network’s temporal and transfer learning components. The generalisability of our system to different surgical setups and procedures was also evaluated qualitatively on in-vivo data of gastric endoscopy and ex-vivo porcine data (SERV-CT, SCARED). We also assess the effect of our method in comparison to other methods on computer vision tasks that underpin 3D reconstruction and camera motion estimation, namely stereo disparity, optical flow, and sparse point feature matching. These are evaluated quantitatively and qualitatively and results show a positive effect of our specular inpainting method on these tasks in a novel comprehensive analysis. Our code and dataset are made available at https://github.com/endomapper/Endo-STTN.

Endomapper dataset of complete calibrated endoscopy procedures

Computer-assisted systems are becoming broadly used in medicine. In endoscopy, most research focuses on the automatic detection of polyps or other pathologies, but localization and navigation of the endoscope are completely performed manually by physicians. To broaden this research and bring spatial Artificial Intelligence to endoscopies, data from complete procedures is needed. This paper introduces the Endomapper dataset, the first collection of complete endoscopy sequences acquired during regular medical practice, making secondary use of medical data. Its main purpose is to facilitate the development and evaluation of Visual Simultaneous Localization and Mapping (VSLAM) methods in real endoscopy data. The dataset contains more than 24 hours of video. It is the first endoscopic dataset that includes endoscope calibration as well as the original calibration videos. Meta-data and annotations associated with the dataset vary from the anatomical landmarks, procedure labeling, segmentations, reconstructions, simulated sequences with ground truth and same patient procedures. The software used in this paper is publicly available.

Non eosinophilic chronic stricturing esophagitis: Lessons from thirty eight cases.

The endoscopic workup of dysphagia can lead to the diagnosis of atypical esophagitis, with thickened esophageal mucosa, strictures, mucosal exudates, furrows, and sloughing. While these aspects suggest eosinophilic esophagitis, pathology might not report the presence of eosinophils, but rather chronic inflammation, with spongiosis, parakeratosis, and lymphocytic infiltrate. We aimed to report the management of this disease and assess the prevalence of associated dermatological conditions. We retrospectively evaluated the medical records of our patients with non-eosinophilic stricturing esophagitis for clinical, endoscopy, and pathology data. Patients were evaluated by a dermatologist. A blood immunoassay and skin biopsy were performed if needed. Thirty-eight patients (twenty-six women) were included in the study. The median age at onset of symptoms was 56.5 years, with a median duration of symptoms of two years. Thirty-five patients presented with dysphagia at diagnosis and eighteen with weight loss. At endoscopy, a single esophageal stenosis was diagnosed in 19 patients, localized in the upper third in 22 patients. Thirty patients received endoscopic treatment (dilatation in 29/38 and local triamcinolone injection in 11/38 patients). In 21 patients, oral, skin or vulvo-anal lesions were found on dermatological examination. Nineteen patients received systemic treatment, including corticosteroids, immunosuppressive drugs and plasmapheresis. Five patients developed esophageal squamous cell carcinoma. The management of non-eosinophilic chronic stricturing esophagitis is challenging, because of a low contribution of esophageal biopsies and the refractory nature of the strictures. In our experience, a dermatological evaluation helped in 55% of cases to introduce a systemic treatment, leading to limit the use of endoscopic dilatation. Endoscopic follow-up is needed, considering the significant risk of esophageal squamous cell carcinoma.

Outcome of Very Early Onset Inflammatory Bowel Disease Associated With Primary Sclerosing Cholangitis: A Multicenter Study From the Pediatric IBD Porto Group of ESPGHAN.

Whether primary sclerosing cholangitis related to inflammatory bowel disease (PSC-IBD) diagnosed before 6 years (ie, VEO-IBD) has a distinct phenotype and disease course is uninvestigated. We aimed to analyze the characteristics and natural history of VEO-PSC-IBD, compared with early and adolescent-onset PSC-IBD. This is a multicenter, retrospective, case-control study from 15 centers affiliated with the Porto and Interest IBD group of ESPGHAN. Demographic, clinical, laboratory, endoscopic, and imaging data were collected at baseline and every 6 months. Inflammatory bowel disease-related (clinical remission, need for systemic steroids and biologics, and surgery) and PSC-related (biliary and portal hypertensive complications, need for treatment escalation and liver transplantation, cholangiocarcinoma, or death) outcomes were compared between the 2 groups. Sixty-nine children were included, with a median follow-up of 3.63 years (interquartile range, 1-11): 28 with VEO-PSC-IBD (23 UC [82%], 2 IBD-U [7%] and 3 [11%] CD), and 41 with PSC-IBD (37 UC [90%], 3 IBDU [7.5%] and 1 [2.5%] CD). Most patients with UC presented with pancolitis (92% in VEO-PSC-UC vs 85% in PSC-UC, P = .2). A higher number of patients with VEO-PSC-IBD were diagnosed with PSC/autoimmune hepatitis overlap syndrome than older children (24 [92%] vs 27 [67.5%] PSC-IBD, P = .03), whereas no other differences were found for PSC-related variables. Time to biliary strictures and infective cholangitis was lower in the VEO-PSC-IBD group (P = .01 and P = .04, respectively), while no difference was found for other outcomes. No cases of cholangiocarcinoma were reported. Primary sclerosing cholangitis related to inflammatory bowel disease has similar baseline characteristics whether diagnosed as VEO-IBD or thereafter. A milder disease course in terms of biliary complications characterizes VEO-PSC-IBD.

Utility of the Serum-Based Endoscopic Healing Index in Monitoring Therapeutic Response in Ulcerative Colitis.

Convenient and objective noninvasive tools to monitor therapy response in patients with ulcerative colitis (UC) are needed. This study aimed to evaluate the performance of the Endoscopic Healing Index [EHI], a serum test originally developed to monitor mucosal inflammation in Crohn's disease, in patients with UC. Serum samples paired with endoscopic data from consecutive adult patients with UC initiating advanced therapy for active disease (Mayo Endoscopic Subscore [MES] > 1) were analyzed. EHI values were compared between groups showing endoscopic improvement, remission, and nonresponse, defined, respectively, as MES of ≤1, 0 and >1. We also assessed the association of EHI with longitudinal changes of MES and compared its performance with that of fecal calprotectin (FC) and C-reactive protein. A total of 127 patients provided 303 samples. Median EHI increased significantly with increasing MES score ( P < 0.001). Median EHI was significantly lower in patients with endoscopic remission or improvement compared with patients with no response ( P < 0.001, P < 0.001, respectively). A 10-point decrease in EHI was associated with 89% higher odds of 1-point decrease in MES ( P < 0.001). EHI detected MES 0-1 with an area under the receiver operating curve of 77.8%, which was comparable with that of FC and C-reactive protein (85.0% [ P = 0.076] and 70.6% [ P = 0.055], respectively). EHI values are significantly responsive to changes in mucosal inflammation, also in patients with UC, and can confirm and/or rule out mucosal inflammation with an almost similar accuracy to that of FC.

Intraoperative Neuromonitoring Does Not Reduce the Risk of Temporary and Definitive Recurrent Laryngeal Nerve Damage during Thyroid Surgery: A Systematic Review and Meta-Analysis of Endoscopic Findings from 73,325 Nerves at Risk.

While intraoperative neuromonitoring (IONM) helps the early identification of recurrent laryngeal nerve (RLN) damage, IONM's role in RLN damage prevention is not defined, given the lack of large studies on the subject. In a PRISMA-compliant framework, all original thyroid surgery prospective studies providing early postoperative endoscopic data for all patients were pooled in a random-effects meta-analysis. We compared the temporary (and definitive where available) RLN damage rates according to IONM use and IONM type (intermittent, I-IONM, or continuous, C-IONM). We identified 2358 temporary and 257 definitive RLN injuries in, respectively, 73,325 and 66,476 nerves at risk. The pooled temporary and definitive RLN injury rates were, respectively, 3.15% and 0.422% considering all procedures, 3.29% and 0.409% in cases using IONM, and 3.16% and 0.463 in cases not using IONM. I-IONM and C-IONM, respectively, showed a pooled temporary RLN injury rate of 2.48% and 2.913% and a pooled definitive injury rate of 0.395% and 0.4%. All pooled rates had largely overlapping 95% confidence intervals. Our data suggest that IONM does not affect the temporary or definitive RLN injury rate following thyroidectomy, though its use can be advised in selected cases and for bilateral palsy prevention.

Evaluation of Gastrointestinal System Complaints and Comorbidities in Pediatric Familial Mediterranean Fever Patients.

Familial Mediterranean fever (FMF) is the most prevalent hereditary autoinflammatory disease among children. Abdominal pain and various gastrointestinal system (GIS) manifestations may arise directly from FMF or concomitantly with FMF. This study aimed to evaluate GIS complaints and findings other than classic peritonitis attacks in patients with FMF and to interpret concomitant GIS and hepatic disorders in these patients. The medical and genetic findings of patients with FMF who attended our clinic between December 2011 and December 2021 were reviewed. Gastrointestinal system symptoms, liver function tests, abdominal images, and endoscopic and histopathological data were extracted from medical records. A total of 576 pediatric patients (female, 52.3%) diagnosed with FMF were included. Among them, almost one-fifth displayed GIS complaints, such as abdominal pain, defecation problems, and dyspepsia, distinct from typical FMF attacks. High serum aminotransferase levels were detected in 18.4% of the patients, with viral infections being the most common cause of moderate/severe hypertransaminasemia. In addition, during follow-up, 26.9% of them were referred to the pediatric gastroenterology department. At least 1 gastroenterological and hepatobiliary disorder was detected in 17.5% of the patients because of organic and functional GIS disorders or hepatobiliary disorders, such as gastroesophageal reflux disease, esophagitis, functional dyspepsia, and inflammatory bowel diseases. Various GIS and hepatic disorders can be encountered in children with FMF. The spectrum of these complaints and pathologies can range from frequently observed health problems to more severe diseases.

Routine Endoscopy Prior to Surgical Ostomy Closure: An Obsolete Concept

BackgroundClosure of temporary diverting ostomies is commonly preceded by an endoscopic study of the colonic mucosa and anastomosis, despite lacking evidence of its relevance and impact on subsequent operative management.AimWe sought to determine the incidence of pathological findings and therefore evaluate the clinical benefit of routine pre-operative endoscopy in asymptomatic patients, hypothesizing sole evaluation of the anastomotic integrity to be sufficient in these cases.MethodsWe retrospectively identified all adult patients with ostomy installations who were followed up for potential reversal surgery between 2002 and 2020 at the University Hospital of Zurich, Switzerland. Main outcome measures were the incidence of endoscopically identified pathological findings in the asymptomatic case cohort and their impact on the subsequent course of treatment.ResultsPre-procedural endoscopic data of 187 cases evaluated for ostomy closure were evaluated. Relevant mucosal findings in the asymptomatic cohort were documented in 26.3% and findings at the anastomotic site detected in 8.7%. A change in subsequent surgical management was noted in 10 patients of the entire cohort (5.3%) and in 9 (5.1%) of all asymptomatic cases. Upon multivariate analyses, the age range of 51 to 60 years old was found to be significantly linked to the presence of endoscopic findings entailing a change in patient management.ConclusionOur findings strongly suggest ostomy closure surgery without previous assessment of the bowel mucosa by means of endoscopy to be acceptable in asymptomatic patients. However, we found it to be indicated in all patients meeting the screening criteria for colorectal carcinoma.

Automatic Registration of Anatomical Structures of Stereo-Endoscopic Point Clouds

Abstract In image-guided surgery, imaging systems such as (stereo-)endoscopes allow intra-operative 3D reconstructions in form of point clouds. However, endoscopes provide only a narrow field of view, resulting in a confined point cloud. In this paper, we present an analysis and registration pipeline for confined point clouds acquired by stereo endoscopes into a fused representation. For a coarse registration, TEASER is applied, while a refinement is conducted utilizing point-to-plane ICP. The pipeline is tested on two datasets: acquired point clouds of a head phantom using a EinsteinVision® 3.0 endoscope and point clouds from the Stereo Correspondence And Reconstruction of Endoscopic Data challenge. The results for both datasets show that 3D reconstructions of anatomical structures by utilizing stereo-endoscopes and point cloud registration is a promising contactless and radiation-free method. However, non-rigid deformations are not yet incorporated and evaluation of the method compared to reference data is challenging.

Tissue Cyclooxygenase-2 Activity in Juvenile Polyposis Syndrome versus Solitary Juvenile Polyps among Pediatric Patients

Background Polyps are the most common benign lesions of the colon; they arise from the inner lining and usually protrude into the lumen of the large intestine. Amongst these, the juvenile polyps are the commonest of the pediatric population and may occur in juvenile polyposis syndrome (JPS) or most often sporadically. Yet to mention that the expression "juvenile" points to the type of polyp, rather than to the age of onset of these polyps. Aim of the Work We aimed to evaluate tissue cyclooxygenase-2 activity in juvenile polyposis syndrome versus solitary juvenile polyps among pediatric patients. In order to identify a possible role of COX-2 inhibitors in treatment and management of children with JPS. Patients and Methods The study enrolled 15 patients with juvenile polyposis syndrome as cases and 15 patients with solitary juvenile polyps as control. The collected polyps’ samples from routine endoscopic polypectomies intervention were proceeded for immunohistochemistry method on tissue microarray using Anti-COX-2 antibody to evaluate and compare its activity in polyps of JPS and SJP. Demographic, clinicopathological, and endoscopic data were obtained. Results Thirteen children with JPS were included in the study with mean age ±SD (7.2± 3.2) years and 7 (46.7%) patients were males, SJP control group included 13 children with mean age ±SD (5.8± 3.5) years, 9 (60%) male patients. Number of lower endoscopies and upper endoscopies was significantly higher in JPS group with P-value=0.009, 0.032 respectively. Intussusception was significantly higher in juvenile polyposis syndrome patients compared to control group with P-value=0.032. COX-2 expression was nonsignificantly different in cases group compared to control group patients with P-value= 0.464. Conclusion COX-2 expression is nonsignificantly higher in polyps of JPS patients in comparison to solitary juvenile polyp patients.

Gastric Cancer Risk Factors ina Veteran Population.

Risk factors for gastric cancer in the United States are not well understood, especially in populations with a low proportion of immigrants. We conducted a matched case-control study in a Veteran Affairs Medical Center to identify risk factors for gastric cancer. Gastric cancer patients and age- and sex-matched controls were identified in a 1:4 ratio from January 1, 1997 to October 31, 2018. Demographic, medical, endoscopic, and histologic data were extracted. We performed conditional logistic regression to estimate odds ratios and 95% CIs for associations between potential risk factors and gastric cancer. Most gastric cancer cases were diagnosed on initial endoscopy (71.4%). Of these, the most common presenting stage was stage IV (40.8%). Risk factors for gastric cancer included Black and Asian race and never or current (compared to former) drinkers, although Helicobacter pylori eradication and pernicious anemia were associated with decreased risk. The high proportion of late-stage gastric cancer diagnoses highlights the need for improved risk stratification as well as screening and surveillance protocols in the U.S. population. Racial disparities among veterans in an equal-access system necessitate further investigation into the etiology of these disparities.

Optimizing individualized management of patients with ulcerative colitis: Identification of risk factors predicting ulcerative colitis-associated neoplasia.

The risk of developing colorectal neoplasia in patients with ulcerative colitis (UC) is increased. The purpose of this study is to analyze the risk factors of UC-associated neoplasia (UCAN) in UC patients and establish a clinical prediction model. 828 UC patients were included in this retrospective study. 602 patients were in discovery cohort and 226 patients were in validation cohort (internal validation cohort/external validation cohort: 120/106). Clinical and endoscopic data were collected. The discovery cohort was divided into UC group and UCAN group for univariate and multivariate binary logistic analyses. The UCAN clinical prediction model was established and verified. In the univariate analysis, 7 risk factors were related to UCAN. Multivariate logistic regression analysis showed that age at diagnosis of UC (OR: 1.018, 95% CI: 1.003-1.033), Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score (OR: 1.823, 95% CI: 1.562-2.128), and size of polyps (size1: OR: 6.297, 95% CI: 3.669-10.809; size2: OR: 12.014, 95% CI: 6.327-22.814) were independent risk factors of UCAN. A mathematical equation was established. The area under the ROC curve (AUC) of this model was calculated to be 0.845 (95%CI: 0.809-0.881). The sensitivity was 0.884 and the specificity was 0.688. The AUC of internal validation cohort was 0.901 (95%CI: 0.815, 0.988), sensitivity was 75.0% and specificity was 92.6%. The AUC of external validation cohort was 0.842 (95%CI: 0.709, 0.976), sensitivity was 62.5% and specificity was 93.9%. This prediction model is simple, practical, and effective for predicting the risk of UCAN, which is beneficial to the individualized management of patients with UC.