Colonic Segments Research Articles

Preferential Neurogenesis of Nitrergic Neurons in the Myenteric Plexus of the DSS-induced Colitis Mouse Colon Causes Colonic Dysmotility in Colitis.

male C57BL/6N mice (12-week-old) were administered 2% DSS in their drinking water for 8 days. After DSS treatment, cross-sections and longitudinal muscle and myenteric plexus preparations from the colon were used for immunohistochemistry. The segments of colons were mounted in organ baths and then exposed to a voltage-gated sodium channel activator veratridine. in the motility study, veratridine-induced colonic contractions were significantly suppressed in DSS-induced colitis mice compared to normal mice. Immunohistochemical analyses revealed that the proportion of nitrergic neurons per ganglion was significantly increased in the colons of DSS-induced colitis mice compared to normal mice. Furthermore, the proportion of Sox2 (new-born neuron marker)-positive neurons per ganglion was not significantly different between normal mice and DSS-induced colitis mice, whereas the proportion of Sox2-positive nitrergic neurons to Sox2-positive neurons per ganglion was significantly increased in the colons of DSS-induced colitis mice compared to normal mice. In addition, NOS inhibitor significantly enhanced veratridine-induced colonic contractions in DSS-induced colitis mice compared with normal mice. these findings suggested that colitis caused an imbalance in the enteric neural circuit composed of excitatory neurons and inhibitory neurons in the myenteric plexus of the colon, which resulted in colonic dysmotility.

MugenNet: A Novel Combined Convolution Neural Network and Transformer Network with Application in Colonic Polyp Image Segmentation

Accurate polyp image segmentation is of great significance, because it can help in the detection of polyps. Convolutional neural network (CNN) is a common automatic segmentation method, but its main disadvantage is the long training time. Transformer is another method that can be adapted to the automatic segmentation method by employing a self-attention mechanism, which essentially assigns different importance weights to each piece of information, thus achieving high computational efficiency during segmentation. However, a potential drawback with Transformer is the risk of information loss. The study reported in this paper employed the well-known hybridization principle to propose a method to combine CNN and Transformer to retain the strengths of both. Specifically, this study applied this method to the early detection of colonic polyps and to implement a model called MugenNet for colonic polyp image segmentation. We conducted a comprehensive experiment to compare MugenNet with other CNN models on five publicly available datasets. An ablation experiment on MugenNet was conducted as well. The experimental results showed that MugenNet can achieve a mean Dice of 0.714 on the ETIS dataset, which is the optimal performance on this dataset compared to other models, with an inference speed of 56 FPS. The overall outcome of this study is a method to optimally combine two methods of machine learning which are complementary to each other.

Determination of optimal cutoff value of ulcerative colitis intestinal ultrasound index to estimate endoscopic improvement in ulcerative colitis.

The ulcerative colitis intestinal ultrasound (UC-IUS) index (UII) has been reported as a sonographic scoring system correlating with the Mayo endoscopic subscore (MES). Endoscopic improvement (EI) of UC (MES ≤ 1) is a crucial therapeutic target in clinical practice. However, the cutoff value for estimating EI using the UII has not been established. We established test and validation cohorts comprising patients with UC undergoing IUS and endoscopy within a 15-day interval at our institution. IUS findings (bowel wall thickness, bowel blood flow, bowel wall structure, haustrations, and inflammatory fat) and endoscopic activity (MES) of each colon segment (ascending, transverse, descending, and sigmoid colon) were assessed. In the test cohort (74 segments), UII was correlated with MES (r = 0.645, p < 0.0001). The median UII was 1.0 and 6.0 among participants with MES ≤ 1 and MES ≥ 2, respectively. A UII of 2 was identified as the threshold for estimating MES ≤ 1 with receiver operating characteristic analysis. In the validation cohort (122 segments), UII was correlated with MES (r = 0.675, p < 0.0001) and the estimation ability of UII ≤ 2 for EI had a positive predictive value of 85.4% and negative predictive value of 79.0%. This estimation ability of UII for EI was numerically lower but not statistically different from the previously reported Milan Ultrasound Criteria and Kyorin Ultrasound Criterion for UC. UII ≤ 2 can be a simple, feasible criterion for estimating EI. Correlation with MES is an advantage of the UII compared with other criteria. Proper use of various sonographic criteria is important.

Simplified magnetic resonance index of activity score versus simple endoscopic score in Crohn's disease: prospective study

BackgroundTo evaluate the correlation between simplified MR index of activity (sMaRIA) score and simple endoscopic score (SES-CD) in Crohn's disease activity assessment. A prospective study was done on established Crohn's disease patients referred to our institution. Magnetic resonance enterography and colonoscopy were performed as an activity assessment protocol searching for activity signs through calculation of sMaRIA score and SES-CD score and correlation between them. One hundred patients were enrolled in the study in period from July 2021 to July 2022. Patients with isolated upper gastrointestinal Crohn's disease (n = 4) or performed surgery before completion of activity assessment protocol (n = 9) or dropout (n = 18) were excluded. Patients with any age group, with ileal or colonic or ileo-colonic Crohn's disease and completed the protocol were eligible for the study (n = 69).ResultsSixty-nine patients with 345 bowel segments (five segments for each patient: ileum, right colon, transverse colon, left colon/sigmoid and rectum) were completely evaluated: 33 males and 36 females with mean age 29.16 ± 11.37 years. sMaRIA and SES-CD scores were calculated for each patient (global), and each bowel segment showed 97.50% sensitivity and 79.31% specificity at the level of global scores as well as significant positive correlation between the two scores at patient level/overall segments (rs = 0.816, p < 0.001), at ileal segments (rs = 0.704, p < 0.001) and colonic segments (right colon rs = 0.661, p ≤ 0.001, transverse colon rs = 0.586, p ≤ 0.001, left colon rs = 0.731, p < 0.001 and rectum rs = 0.786, p < 0.001). There were good inter-rater agreement between the two radiologists for the three parameters (wall thickness > 3 mm, mural edema and fat stranding) and moderate for mucosal ulcer detection with k value 0.666, 0.712, 0.712 and 0.565, respectively.ConclusionssMaRIA score is considered to be a reliable tool for Crohn's disease activity evaluation as compared to SES-CD.

Oncologic outcomes and trends in each colon cancer location and stages over the last two decades: insights from the SEER registry.

The main purpose of the study is to comprehensively evaluate population-level survival disparities stage-by-stage, according to specific anatomical colon segments, and based on prognosis as defined by lymph nodes among patients who have undergone curative resection for non-metastatic colon cancer. The study was conducted from the Surveillance Epidemiology and End Result (SEER) program from the USA. Patients who underwent surgery for colon adenocarcinoma between 2000 and 2019 were identified. Demographics and clinical and pathologic factors were compared amongst each other according to different colon segments, stages, and time periods. A total of 482,672 patients were identified and 195,105 of them met the inclusion criteria. Patients with proximal cancers were significantly older, more likely to be female, had a higher number of lymph nodes, and node positivity (p < 0.001). During the study period, an almost 10% improvement in overall survival rate was observed at 3 and 5years for each colon site and stage (p < 0.05). The study's findings revealed a notable improvement in overall and cancer-specific survival rates across all colon segments and stages in patients who underwent curative treatment for non-metastatic primary colon cancer from a nationwide database.

Investigation into Critical Gut Microbes Influencing Intramuscular Fat Deposition in Min Pigs.

To determine the pivotal microorganisms affecting intramuscular fat (IMF) accumulation in Min pigs and to discern the extent of the influence exerted by various intestinal segments on IMF-related traits, we sequenced 16S rRNA from the contents of six intestinal segments from a high IMF group (Group H) and a low IMF group (Group L) of Min pigs weighing 90 ± 1 kg. We then compared their diversity and disparities in bacterial genera. Group H exhibited considerably higher α diversity in the jejunum and colon than Group L (p < 0.05). When 95% confidence levels were considered, the main β diversity components for the ileum, caecum, and colon within Groups H and L exhibited absolute segregation. Accordingly, 31 differentially abundant genera across Group H were pinpointed via LEfSe and the Wilcoxon test (p < 0.05) and subsequently scrutinised based on their distribution and abundance across distinct intestinal segments and their correlation with IMF phenotypes. The abundances of Terrisporobacter, Acetitomaculum, Bacteroides, Fibrobacter, Treponema, Akkermansia, Blautia, Clostridium sensu stricto 1, Turicibacter, Subdoligranulum, the [Eubacterium] siraeum group, and dgA 11 gut groups were positively correlated with IMF content (p < 0.05), whereas those of Bacillus, the Lachnospiraceae NK4A136 group, Streptococcus, Roseburia, Solobacterium, Veillonella, Lactobacillus, the Rikenellaceae RC9 gut group, Anaerovibrio, and the Lachnospiraceae AC2044 group were negatively associated with IMF content (p < 0.05). Employing PICRUSt2 for predicting intergenic metabolic pathways that differ among intestinal microbial communities revealed that within the 95% confidence interval the colonic microbiome was enriched with the most metabolic pathways, including those related to lipid metabolism. The diversity results, bacterial genus distributions, and metabolic pathway disparities revealed the colonic segment as an influential region for IMF deposition.

Prevalence of an empty colon in patients with acute and chronic small intestinal mechanical obstruction: A retrospective radiographic study in 100 dogs and cats

Small intestinal mechanical obstruction (SIMO) is a common clinical condition, with radiographic studies typically focusing on the small intestine. However, the colon's appearance in SIMO has not been extensively studied. This retrospective study aimed to determine the prevalence of an empty colon on radiographs of dogs and cats with confirmed SIMO. Pre-surgical abdominal radiographs of 100 patients (68 dogs and 32 cats) with surgically confirmed mechanical ileus and a control group of 30 dogs and 20 cats with non-obstructive gastrointestinal (GI) disease and one without GI disease, respectively, were evaluated. The colon was assessed for content (none/collapsed, gas, faeces) and segmental distribution (ascending, transverse, descending colon) and correlated to the duration of clinical signs (acute, chronic). A colon was classified as empty when ≥2/3 was collapsed and/or gas-filled. The overall prevalence of an empty colon in cases of mechanical ileus was 61% (p=0.028), with 49/68 in dogs (72.1%) and 12/32 in cats (37.5%), p=0.001 between dogs and cats. Clinical signs duration did not influence the prevalence 28/61 (45.9%) acute, 33/61 (54.1%) chronic, p=0.522. However, acute cases had more empty colon segments (2/3 segments: 6/28, 21.4%; 3/3 segments: 22/28, 78.6%) than chronic cases (2/3 segments: 23/33, 69.7%; 3/3 segments: 10/33, 30.3%; p≤0.001). In the control groups, the prevalence of an empty colon was 64% (p=0.048) with and 38%, p=0.048) without GI disease, with no statistical difference between dogs and cats. An empty colon can be a supporting radiographic finding in diagnosing patients with GI disease, including SIMO, in addition to other established characteristic features. Dogs are more likely to have an empty colon in the presence of mechanical ileus.

Differentially Expressed Somatostatin (SST) and Its Receptors (SST1-5) in Sporadic Colorectal Cancer and Normal Colorectal Mucosa.

Colorectal cancer (CRC) is one of the most common human malignancies worldwide. The somatotropin-releasing inhibitory factor/somatostatin (SRIF/SST) acts through activation of five membrane receptors (SSTRs, SST1-5). The diagnostic and prognostic role of these peptides in sporadic CRC remains unclear. This study aimed to determine the role of tissue expression of SST and all SSTRs in the pathogenesis, diagnosis, and prognosis of sporadic CRC. The expression of SST and all SSTRs was assessed in the tissues of CRC patients, control colorectal mucosa and lymph node metastasis from the same patients using real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). Decreased SST (mRNA and peptide) and higher SST2 and SST5 (mRNA and peptide) expression in CRC vs. control was noted. A negative correlation between SST mRNA expression and patient's age in CRC and control groups were observed. IHC study confirmed the coexpression of SSTRs in all tissue groups and significant dependence on the cellular localization. Immunoexpression of SST2 and SST3 showed the most correlations with clinicopathological data in CRC patients. Interestingly, only control tissue showed differences in SST1-5 expression depending on the colon segment. Reduced SST expression in CRC indicates a weakening in its antitumor effect in this cancer in vivo. Overexpression of SST2 and SST5 in CRC suggests that these receptors play an important role in the pathogenesis of this cancer. Analysis of SST1-5 tissue expression allows for differentiation between the mucinous and nonmucinous CRC subtypes. The coexpression of all SST1-5 and overexpression of not only SST2 and SST5 in CRC may have applications for future therapy based on the SRIF system in sporadic CRC.

Analysis of the outcomes of postdiverticulitis investigations: a multicentre cohort study including 1,120 patients.

The aim of this study was to assess the yield of the endoscopic investigations performed following the resolution of acute diverticulitis. A retrospective multicentre study included patients with multislice computed tomography (MSCT)-proven diverticulitis, in four NHS hospitals, between January 2016 and April 2023. The primary outcome was the rate of colonic cancer in the diseased segment. Secondary outcomes included the rate of malignancy in the nondiseased colonic segments, the benign colonic polyp detection rate, the rate of malignancy in the resected surgical specimens in patients who underwent an emergency surgery on the index admission and the rate of complications in the investigated group. A total of 1,120 patients were included in the study, out of which 604 were females, with a median age of 61 years; 731 patients (65%) had uncomplicated diverticulitis (Hinchey 1A) while 389 (35%) had complicated diverticulitis (Hinchey 1B-4). Following the acute episode, 757 (74%) patients had subsequent endoscopic evaluation. The incidence of colorectal cancer (CRC) or advanced adenomas (AA) in patients with uncomplicated diverticulitis was 0.14%. In the complicated diverticulitis group, the incidence of CRC/AA in patients with Hinchey 1b and Hinchey 2 was 1.4% and 5.4%, respectively. Out of the 102 patients who underwent emergency colonic resection for suspected perforated diverticulitis, 18 (17.6%) had histological evidence of colonic malignancy. Endoscopic investigations following uncomplicated diverticulitis have a low yield for sinister colonic pathology. Colonoscopy should be planned following complicated diverticulitis and in patients with uncomplicated diverticulitis with suspicious radiological finding on index imaging or in patients with ongoing clinical manifestations. In patients who undergo emergency surgery, oncological principles should be applied whenever possible.

Lubiprostone Improves Distal Segment-Specific Colonic Contractions through TRPC4 Activation Stimulated by EP3 Prostanoid Receptor

Background: Prokinetic agents are effective in increasing gastrointestinal (GI) contractility and alleviating constipation, often caused by slow intestinal motility. Lubiprostone (LUB), known for activating CLC-2 chloride channels, increases the chloride ion concentration in the GI tract, supporting water retention and stool movement. Despite its therapeutic efficacy, the exact mechanisms underlying its pharmacological action are poorly understood. Here, we investigated whether LUB activates the canonical transient receptor potential cation channel type 4 (TRPC4) through stimulation with E-type prostaglandin receptor (EP) type 3. Methods: Using isotonic tension recordings on mouse colon strips, we examined LUB-induced contractility in both proximal and distal colon segments. Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to determine mRNA levels of EP1-4 receptor subtypes in distal colonic muscular strips and isolated myocytes. The effects of a TRPC4 blocker and EP3 antagonist on LUB-stimulated contractions were also evaluated. Results: LUB showed significant contraction in the distal segment compared to the proximal segment. EP3 receptor mRNA levels were highly expressed in the distal colon tissue, which correlated with the observed enhanced contraction. Furthermore, LUB-induced spontaneous contractions in distal colon muscles were reduced by a TRPC4 blocker or EP3 antagonist, indicating that LUB-stimulated EP3 receptor activation may lead to TRPC4 activation and increased intracellular calcium in colonic smooth muscle. Conclusions: These findings suggest that LUB improves mass movement through indirect activation of the TRPC4 channel in the distal colon. The segment-specific action of prokinetic agents like LUB provides compelling evidence for a personalized approach to symptom management, supporting the defecation reflex.

New Approaches Based on Inflammatory Indexes in the Evaluation of the Neoplastic Potential of Colon Polyps

Colorectal polyps, precursors to colorectal cancer (CRC), require precise identification for appropriate diagnosis and therapy. This study aims to investigate the differences in hematological and inflammatory markers, specifically the CALLY index, HALP score, and immuno-inflammatory indexes, between neoplastic and nonneoplastic polyps. A retrospective cross-sectional study was conducted on 758 patients aged 61.0 ± 11.8 who underwent polypectomy between June 2021 and May 2024. Patients with colorectal adenocarcinoma (n = 22) were excluded. The polyps were classified into neoplastic and nonneoplastic categories based on histopathological evaluation. The study compared the CALLY index, HALP score, and various inflammatory indexes between neoplastic and nonneoplastic polyps. Out of 758 polyps analyzed, 514 were neoplastic, and 244 were nonneoplastic. Neoplastic polyps exhibited significantly lower CALLY and HALP scores (p &lt; 0.05) and higher immuno-inflammatory indexes (p &lt; 0.05) compared to nonneoplastic polyps. Dysplasia status, polyp diameter, and sigmoid colon localization were significant factors in determining neoplastic growth potential. No significant differences were observed in polyp localization in the proximal and distal colon segments or in solitary versus multiple polyps. The CALLY and HALP scores and immuno-inflammatory indexes can serve as valuable markers for distinguishing neoplastic from nonneoplastic polyps. These indexes reflect underlying inflammatory and immune responses, highlighting their potential utility in the early detection and risk stratification of colorectal polyps. Integrating these markers into clinical practice may enhance diagnostic accuracy and improve patient management, leading to timely interventions and better outcomes for individuals at risk of CRC.

A novel colonoscope with an extra-wide field of view increases polyp detection rate compared with standard colonoscope: Prospective model-based trial.

Background and study aims Colonoscopy, the gold standard for early detection of colorectal cancer, may miss polyps especially those hidden behind folds. This prospective study compared polyp detection and performance of a novel colonoscope with extra-wide field of view (EFOV) of 230 degrees (partially retrograde) to a standard colonoscope (SC, 170 degrees) in a colon model. Patients and methods A 3D printed colon model was used featuring 12 polyps placed throughout different colon segments, with several located on the proximal side of haustral folds. Endoscopists were instructed to identify polyps, first inserting the SC immediately followed by the EFOV device, and to place a snare to simulate a polypectomy. A standardized survey was used to record operator impressions. Results Twenty-nine experienced endoscopists participated in this study. On average, 5.3 vs 9.6 polyps were detected with the standard and EFOV colonoscopes, respectively ( P < 0.001). Five of 29 operators (17.2%) detected all 12 polyps with the EFOV device, whereas no operator detected all polyps with the SC. The success rate for snare placement was 100% for both endoscopes with similar times (mean of 14 vs 15 seconds for SC and EFOV, respectively). EFOV handling and optical performance were rated as equally good or better by all endoscopists. Conclusions Use of a colonoscope with novel optics significantly improved polyp detection compared with a standard colonoscope in this non-randomized model-based study, with favorable performance and usability ratings for the EFOV instrument. Clinical studies are needed to confirm these encouraging preliminary results.

Detecting and characterizing creeping fat in Crohn’s disease: agreement between intestinal ultrasound and computed tomography enterography

ObjectivesCreeping fat (CF) is associated with stricture formation in Crohn’s disease (CD). This study evaluated the feasibility of intestinal ultrasound (IUS) for semiquantitative analysis of CF and compared the agreement between IUS and computed tomography enterography (CTE).MethodsIn this retrospective study, we recruited consecutive CD patients who underwent IUS and CTE. CF wrapping angle was analyzed on the most affected bowel segment and was independently evaluated by IUS and CTE. We evaluated the wrapping angle of CF in the cross- and vertical sections of the diseased bowel. CF wrapping angle was divided into < 180° and ≥ 180°. IUS performance was assessed using CTE as a reference standard, and IUS interobserver consistency was evaluated.ResultsWe enrolled 96 patients. CTE showed that CF wrapping angle was < 180° in 35 patients and ≥ 180° in 61 patients. We excluded three cases in which the observation positions were inconsistent between the IUS and CTE. Excellent agreement was shown between US and CTE (82/93, 88.2%). The eleven remaining cases showed inconsistencies mostly in the terminal ileum (n = 5) and small intestine (n = 4). Total agreement between IUS observers was 89.6% (86/96, κ = 0.839, p = 0.000), with perfect agreement for the ileocecal and colonic segments (35/37, 94.6% and 20/21, 95.2%, respectively) and moderate agreement for small intestinal segments (16/21, 76.2%).ConclusionsIUS could be of value and complementary to CTE for assessing CF, particularly in patients with affected terminal ileum and colon. IUS is a non-invasive technique for monitoring CD patients.Critical relevance statementIn our study, excellent agreement was shown between intestinal US observers as well as between US and CT enterography (CTE) for assessing creeping fat (CF), which showed that ultrasound could be of value and complementary to CTE.Key PointsCreeping fat (CF) is a potential therapeutic target in Crohn’s disease.Excellent agreement was shown between US and CT Enterography (CTE) for assessing CF.Ultrasound could be complementary to CTE for assessing CF.Graphical

Lipopolysaccharide accelerates peristalsis by stimulating glucagon-like peptide-1 release from L cells in the rat proximal colon.

Upon epithelial barrier dysfunction, lipopolysaccharide (LPS) stimulates glucagon-like peptide-1 (GLP-1) secretion from enteroendocrine L cells by activating Toll-like receptor 4 (TLR4). Because GLP-1 accelerates peristalsis in the proximal colon, the present study aimed to explore whether LPS facilitates colonic peristalsis by stimulating L cell-derived GLP-1 release. In isolated segments of rat proximal colon that were serosally perfused with physiological salt solution and luminally perfused with 0.9% saline, peristaltic wall motion was video recorded and converted into spatio-temporal maps. Fluorescence immunohistochemistry was also carried out. Intraluminal administration of LPS (100 or 1µgmL-1 but not 100ngmL-1) increased the frequency of oro-aboral propagating peristaltic contractions. The LPS-induced acceleration of colonic peristalsis was blocked by TAK-242 (the TLR4 antagonist), exendin-3 (the GLP-1 receptor antagonist) or BIBN4096 (the calcitonin gene-related peptide receptor antagonist). GLP-1-positive epithelial cells co-expressed TLR4 immunoreactivity. In aspirin-pretreated preparations where epithelial barrier function had been impaired, a lower dose of LPS (100ngmL-1) became capable of accelerating peristalsis. By contrast, luminally applied dimethyl sulphoxide, a reactive oxygen species scavenger that protects epithelial integrity, attenuated the prokinetic effects of a higher dose of LPS (100µgmL-1). In colonic segments of a stress rat model leading to a leaky gut, LPS induced more pronounced prokinetic effects. Colonic L cells may well sense luminal LPS via TLR4 triggering the release of GLP-1 that stimulates calcitonin gene-related peptide-containing neurons. The resultant acceleration of peristalsis would facilitate excretion of Gram-negative bacteria from the intestine, and thus L cells may have a protective role against intestinal bacterial infections. KEY POINTS: Colonic epithelial cells form a barrier against bacterial invasion but also may contribute more actively to the exclusion of luminal pathogen by stimulating colonic motility. Luminal lipopolysaccharide (LPS) accelerated colonic peristalsis by stimulating calcitonin gene-related peptide-containing neurons. The prokinetic effect of LPS was mediated by the secretion of glucagon-like peptide-1 from enteroendocrine L cells in which Toll-like receptor 4 was expressed. The LPS-mediated acceleration of peristalsis depended on epithelial barrier integrity. L cells have a defensive role against Gram-negative bacterial infections by facilitating faecal excretion, and could be a potential therapeutic target for gastrointestinal infections.

Will Transformers change gastrointestinal endoscopic image analysis? A comparative analysis between CNNs and Transformers, in terms of performance, robustness and generalization

Gastrointestinal endoscopic image analysis presents significant challenges, such as considerable variations in quality due to the challenging in-body imaging environment, the often-subtle nature of abnormalities with low interobserver agreement, and the need for real-time processing. These challenges pose strong requirements on the performance, generalization, robustness and complexity of deep learning-based techniques in such safety–critical applications. While Convolutional Neural Networks (CNNs) have been the go-to architecture for endoscopic image analysis, recent successes of the Transformer architecture in computer vision raise the possibility to update this conclusion. To this end, we evaluate and compare clinically relevant performance, generalization and robustness of state-of-the-art CNNs and Transformers for neoplasia detection in Barrett’s esophagus. We have trained and validated several top-performing CNNs and Transformers on a total of 10,208 images (2,079 patients), and tested on a total of 7,118 images (998 patients) across multiple test sets, including a high-quality test set, two internal and two external generalization test sets, and a robustness test set. Furthermore, to expand the scope of the study, we have conducted the performance and robustness comparisons for colonic polyp segmentation (Kvasir-SEG) and angiodysplasia detection (Giana). The results obtained for featured models across a wide range of training set sizes demonstrate that Transformers achieve comparable performance as CNNs on various applications, show comparable or slightly improved generalization capabilities and offer equally strong resilience and robustness against common image corruptions and perturbations. These findings confirm the viability of the Transformer architecture, particularly suited to the dynamic nature of endoscopic video analysis, characterized by fluctuating image quality, appearance and equipment configurations in transition from hospital to hospital. The code is made publicly available at: https://github.com/BONS-AI-VCA-AMC/Endoscopy-CNNs-vs-Transformers.

Decisions in Diversion: Enterostomy vs. Primary Anastomosis for Colonic Atresia

BackgroundColonic atresia (CA) is associated with Hirschsprung disease (HD) in up to 10% of cases. Therefore, some surgeons elect to complete proximal diversion at the initial operation. We sought to better define the incidence of concurrent HD and evaluate practice patterns regarding diversion for CA. MethodsThe Pediatric Health Information System (PHIS) database was used to identify patients with CA from 2013 to 2022. Patients with small bowel atresia, anorectal malformation, gastroschisis, or first operation after 14 days of age were excluded. Index and subsequent operations were defined. Complications, time to enterostomy closure, and unplanned operations were evaluated. ResultsHD was diagnosed in 8 (9.5%) patients and 7 of these were initially diverted. Diverted and anastomosed patients were demographically similar. In the 58 (69%) patients initially diverted, 19 (33%) had an ileostomy. Continuity was restored with an ileo-colic anastomosis in 63% of diverted and 27% of primarily anastomosed patients. Of those initially managed with a colostomy, 53% ultimately had a colo-colonic anastomosis. Patients with primary anastomoses had fewer operations and received more days of parenteral nutrition. Other outcomes did not vary. ConclusionIn a large population of infants with CA, 9.5% had concurrent HD. Almost 70% of CA patients underwent initial diversion and only one with HD had a primary anastomosis. Patients managed with a primary anastomosis were substantially more likely to retain the proximal colonic segment, but had a similar incidence of complications. When intraoperative colonic biopsies are obtained, primary anastomosis is a safe and effective strategy for CA. Level of Evidence3.

Adverse tissue reactions to ORISE gel during endoscopic mucosal resection and dissection

BackgroundSubmucosal injection of lifting agents (LAs) is frequently used to facilitate endoscopic mucosal resection or endoscopic submucosal dissection. ORISE (Boston Scientific Corporation) gel, approved in 2018 by the United States Food and Drug Administration, has been commonly used until recently. Its use proliferated because of its practical prefilled syringe, prolonged lift effect, and ideal coloration. However, it has been noted to cause unexpected tissue reactions, described as “giant cell reaction” (GCR), which can obscure macroscopic and microscopic views, potentially interfering with pathologic evaluation. This study aimed to describe the adverse effects of ORISE gel. MethodsThis retrospective study analyzed pathologic specimens from all consecutive patients who received ORISE injections for attempted polyp removal and subsequently underwent segmental colon resection at our center between 2019 and 2022. A descriptive analysis was performed. ResultsA total of 45 patients were included, of whom 17 (38.0%) were female and the median age was 66 years. The indications for surgery included adenocarcinoma in 14 patients (31%), suspected malignancy in 3 patients (7%) who had benign GCR-induced masses, and other indications in 28 patients, such as large polyps or recurrent polyps after initial endoscopic treatment. Surgical procedures included right hemicolectomy (44%), low anterior resection (13%), left colectomy (11%), sigmoidectomy (7%), and abdominoperineal resection (4%). Histologic evidence of previous LA injection was seen in 31 patients (69%), with 24 patients exhibiting GCR. At final pathology, no residual neoplasm was found in 9 patients (18%); however, 14 patients (31%) had adenocarcinoma (T1 [7], T2 [3], T3 [3], and T4 [1]). ConclusionORISE gel interacts with various tissue layers of the colon, frequently resulting in GCR. This reaction and the potential subsequent mass effect formation can affect decision-making regarding the management of complex colorectal lesions. Further study into the causes and consequences of LA tissue reactions is warranted.

Nitric oxide in the mechanisms of inhibitory effects of sodium butyrate on colon contractions in a mouse model of irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a multifactorial disorder, with altered intestinal motility, visceral hypersensitivity, and dysfunction of the gut-brain axis. The aim of our study was to analyze the role of nitric oxide (NO) in the inhibitory effects of sodium butyrate on spontaneous contractility of proximal colon in a mouse model of IBS. IBS was induced by intracolonic infusion of acetic acid in the early postnatal period. Spontaneous contractions of proximal colon segments were studied in isometric conditions. The amplitude and frequency of colon contractions were higher in the IBS group. Sodium butyrate exerted inhibitory effects on colon contractions, which were less pronounced in IBS group. NO donors decreased spontaneous colon contractility and prevented the inhibitory effects of sodium butyrate in control and IBS groups. Nitric oxide synthase (NOS) inhibition by L-NAME increased contractile activity more effective in the control group and decreased the inhibitory action of sodium butyrate. In IBS group, preliminary application of L-NAME did not prevent sodium butyrate action. Our data indicate that butyrate exerts its inhibitory effects on colon motility at least partially through activation of NO synthesis. In the IBS model group, the NO-dependent mechanisms were less effective probably due to downregulation of NOS.

Four intestinal ultrasound scores and bowel wall thickness alone correlated well with pediatric ulcerative colitis disease activity.

Intestinal ultrasound (IUS) is a noninvasive tool in ulcerative colitis (UC), but scoring systems have mostly been developed for adults, Crohn's disease, and flaring UC. Our aim was to evaluate the performance of bowel wall thickness (BWT) and four IUS scores in pediatric patients with newly diagnosed UC. Patients <18 years old with suspected UC were prospectively enrolled. Baseline IUS was done, and ulcerative colitis intestinal ultrasound score (UC-IUS), Milan criteria, simple pediatric activity ultrasound score (SPAUSS), and Civatelli Index were calculated. Mayo endoscopic segment subscore, pediatric ulcerative colitis activity index (PUCAI), and biomarkers were correlated with IUS using nonparametric and receiver operating characteristic analyses. Fifty-two patients (56% male, median age 13.9 years, interquartile range [IQR] 11.2-16.3) with 206 colon segments were included. Patients who needed hospitalization (n = 27/52) had significantly worse IUS (BWT and all scores) compared to those not hospitalized. For all patients, IUS scores and BWT significantly correlated with baseline endoscopic, clinical, and biochemical disease activity (p = 0.32-0.67, p < 0.05). BWT (τb = 0.53), UC-IUS (τb = 0.55), and Milan (τb = 0.52) had the strongest endoscopic correlations. For differentiating between endoscopic disease severity, BWT, UC-IUS, and Milan, had the highest areas under the curve (0.89-0.93). Using BWT alone, a thinner cut-off had improved sensitivity while maintaining high specificity: ≥2.5 mm for moderate/severe endoscopic inflammation (sensitivity 66%; specificity 94%) and ≥3.5 mm for severe endoscopic inflammation (sensitivity 92%; specificity 86%). BWT and all four IUS scores correlated well with endoscopic, clinical, and biochemical disease activity, and was another useful marker of severity in identifying patients needing hospitalization. Pediatric patients needed a thinner BWT cut-off, which should be accounted for when developing pediatric-specific scores. BWT alone may be just as clinically useful as composite US scores.

Self-Adaptive Teacher-Student framework for colon polyp segmentation from unannotated private data with public annotated datasets.

Colon polyps have become a focal point of research due to their heightened potential to develop into appendiceal cancer, which has the highest mortality rate globally. Although numerous colon polyp segmentation methods have been developed using public polyp datasets, they tend to underperform on private datasets due to inconsistencies in data distribution and the difficulty of fine-tuning without annotations. In this paper, we propose a Self-Adaptive Teacher-Student (SATS) framework to segment colon polyps from unannotated private data by utilizing multiple publicly annotated datasets. The SATS trains multiple teacher networks on public datasets and then generates pseudo-labels on private data to assist in training a student network. To enhance the reliability of the pseudo-labels from the teacher networks, the SATS includes a newly proposed Uncertainty and Distance Fusion (UDFusion) strategy. UDFusion dynamically adjusts the pseudo-label weights based on a novel reconstruction similarity measure, innovatively bridging the gap between private and public data distributions. To ensure accurate identification and segmentation of colon polyps, the SATS also incorporates a Granular Attention Network (GANet) architecture for both teacher and student networks. GANet first identifies polyps roughly from a global perspective by encoding long-range anatomical dependencies and then refines this identification to remove false-positive areas through multi-scale background-foreground attention. The SATS framework was validated using three public datasets and one private dataset, achieving 76.30% on IoU, 86.00% on Recall, and 7.01 pixels on HD. These results outperform the existing five methods, indicating the effectiveness of this approach for colon polyp segmentation.