Triglycerides: A Sensitizer but Not a Trigger for Hypertriglyceridemic Acute Pancreatitis.

BACKGROUND: The incidence of hypertriglyceridemic acute pancreatitis (HTG-AP) is increasing. Although the guideline defines the diagnostic criteria as triglyceride (TG) greater than 11.3 mmol/L, there is actually no specific threshold. Many people with hypertriglyceridemia (HTG) or obvious chyloid blood do not develop acute pancreatitis (AP). AIMS: To explore the role of HTG in the pathogenesis of AP. METHODS: Thirty-six male SD rats were randomly assigned into normal control, AP, HTG, HTG-AP, low-dose fenofibrate and high-dose fenofibrate groups. Serum indices and cytokine levels in serum, and pathological changes in pancreatic tissues were observed. The expression levels of TLR4 and NF-κBp65 in pancreatic tissues were detected by immunohistochemistry and Western blot. RESULTS: In normal rats, HTG alone did not induce AP. However, after establishing the HTG-AP model with Poloxam 407 and L-arginine, serum-free fatty acid and TG levels were positively correlated with the levels of lipase, amylase, IL-1ß, IL-6, pancreatic inflammation scores, and the expressions of TLR4 and NF-κBp65 (all P < 0.001). Expressions of TLR4 and NF-κBp65 were significantly increased in the pancreatic tissues of HTG-AP rats. Fenofibrate effectively decreased TG levels in HTG-AP rats and reduced the expression of TLR4 and NF-κBp65 (all P < 0.001). CONCLUSIONS: HTG does not directly cause AP, but rather increases the susceptibility to AP or aggravates the inflammatory response. It is more like a sensitizer of inflammation rather than an activator.

Mesenteric adipose tissue B lymphocytes promote intestinal injury in severe acute pancreatitis by mediating enteric pyroptosis.

BACKGROUND: Visceral adipose tissue (VAT) has been linked to the severe acute pancreatitis (SAP) prognosis, although the underlying mechanism remains unclear. It has been reported that pyroptosis worsens SAP. The present study aimed to verify whether mesenteric adipose tissue (MAT, a component of VAT) can cause secondary intestinal injury through the pyroptotic pathway. METHODS: Thirty-six male Sprague Dawley (SD) rats were divided into six different groups. Twelve rats were randomly divided into the SAP and control groups. We monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP rats. Twelve SAP rats were injected with MAT B lymphocytes or phosphate buffer solution (PBS). The remaining twelve SAP rats were first injected with MAT B lymphocytes, and then with MCC950 (NLRP3 inhibitor) or PBS. We collected blood and tissue samples from pancreas, gut and MAT for analysis. RESULTS: Compared to the control rats, the SAP group showed inflammation in MAT, including higher expression of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6), lower expression of IL-10, and histological changes. Flow cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and macrophages. The SAP rats also exhibited intestinal injury, characterized by lower expression of zonula occludens-1 (ZO-1) and occludin, higher levels of lipopolysaccharide and diamine oxidase, and pathological changes. The expression of NLRP3 and n-GSDMD, which are responsible for pyroptosis, was increased in the intestine of SAP rats. The injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in MAT. The upregulation of pyroptosis reduced tight junction in the intestine, which contributed to the SAP progression, including higher inflammatory indicators and worse histological changes. The administration of MCC950 to SAP + MAT B rats downregulated pyroptosis, which subsequently improved the intestinal barrier and ameliorated inflammatory response of SAP. CONCLUSIONS: In SAP, MAT B lymphocytes aggravated local inflammation, and promoted the injury to the intestine through the enteric pyroptotic pathway.

Difference in meal-related esophageal intraluminal impedance change between gastroesophageal reflux disease and functional disorders.

OBJECTIVES: Gastroesophageal reflux disease (GERD) has overlapping symptoms with functional disorders such as functional heart burn. Twenty-four-hour pH with impedance monitoring is useful for differentiation. The intraluminal impedance change with meal in distal esophagus is not investigated. METHODS: We performed a retrospective investigation of clinical files, 24-hour pH with intraluminal impedance monitoring in patients with GERD and functional disorders. The post-reflux swallow induced peristaltic wave (PSPW) index as well as the impedance in distal esophagus before the first meal and 30 min and 60 min after the meal were measured and analyzed. RESULTS: A significant decrease of intraluminal impedance in distal esophagus was noted at 30 min (ΔI30min -301.5 [747.5] Ω, p = 0.018) and recovered at 60 min (ΔI60min -194.6 [766.0] Ω, p = 0.126) after meals in GERD patients. On the other hand, there was no significant change of impedance in patients with functional disorders. There were positive correlations between ΔI30min and PSPW index (correlation = 0.232, p = 0.038). Comparing GERD to functional disorders, the best cut-off value for ΔI30min was -212Ω with 74.4% sensitivity and 60.5% specificity. CONCLUSIONS: The intraluminal impedance in distal esophagus was lowered after meals in GERD patients other than functional disorders. This impedance change was correlated with PSPW index and could help differentiate GERD from functional disorders.

Interactive training versus self-driven training in the prediction of colorectal polyp histology by trainees using the NICE classification.

BACKGROUND: The COVID-19 pandemic has impacted endoscopic training of the Narrow Band Imaging International Colorectal Endoscopic (NICE) classification, which could accurately predict pathology of colorectal polyps. This study aimed to evaluate the diagnostic performance by trainees of self-driven training vs. interactive training in the prediction of colorectal polyp histology. METHODS: This was a prospective randomized controlled study at five academic centers from January 1, 2021 to May 31, 2021. Trainees with no previous formal training of narrow band imaging or blue light imaging for prediction of colorectal polyp histology were randomly allocated to the self-driven training group or interactive training group. Before and after the training, all trainees were given 20 selected cases of colorectal polyp for testing. Their diagnostic performance was analyzed. RESULTS: Overall, the two training groups showed similar accuracy of NICE classification (79.3% vs. 78.1%; P = 0.637), vessel analysis (77.8% vs. 77.6%, P = 0.939), and surface pattern analysis (78.1% vs. 76.9%, P = 0.616). The accuracy of color analysis in the interactive training group was better (74.4% vs. 80.0%, P = 0.027). For high-confidence predictions, the self-driven training group showed higher accuracy of NICE classification (84.8% vs. 78.7%, P < 0.001) but no difference for analysis of color (79.6% vs. 81.0%), vessel pattern (83.0% vs. 78.5%), and surface pattern (81.8% vs. 78.5%). CONCLUSIONS: Overall, self-driven training showed comparable accuracy of NICE classification, vessel pattern, and surface pattern to interactive training, but lower accuracy of color analysis. This method showed comparable effectiveness and is more applicable than interactive training. It is worth spreading during the COVID-19 pandemic. Trial registration Name of the registry: Chinese Clinical Trial Registry, Trial registration number: ChiCTR2000031659, Date of registration: 06/04/2020, URL of trial registry record: http://www.chictr.org.cn/showproj.aspx?proj=51994.

Inflammation of Mesenteric Adipose Tissue Correlates with Intestinal Injury and Disease Severity in Rats with Severe Acute Pancreatitis.

BACKGROUND: Visceral adipose tissue (VAT) is related to SAP prognosis. As a depot of VAT, mesenteric adipose tissue (MAT) resides between pancreas and gut, which might affect SAP and the secondary intestinal injury. AIMS: To investigate the changes of MAT in SAP. METHODS: 24 SD rats were randomly divided into four groups. 18 rats in SAP group were euthanized in time gradients (6 h, 24 h, and 48 h after modeling) and the others in control group. Blood samples and tissues of pancreas, gut, and MAT were taken for analysis. RESULTS: Compared to the control group, SAP rats appeared MAT inflammation, presenting higher mRNA expression of TNF-α and IL-6 and lower IL-10, and histological changes after 6 h of modeling, which became worse over time. Flow cytometry showed that B lymphocytes increased in MAT after 24 h of SAP modeling and lasted up to 48 h, earlier than the changes of T lymphocytes and macrophages. The intestinal barrier integrity was damaged after 6 h of modeling, presenting lower mRNA and protein expression of ZO-1 and occludin, higher serum levels of LPS and DAO, with pathological changes, which gradually aggravated after 24 h and 48 h. SAP rats had higher serum levels of inflammatory indicators and revealed histological inflammation of pancreas, the severity of which increased with the passage of modeling time. CONCLUSION: MAT appeared inflammation in early-stage SAP, and became worse over time, with the same trend as the intestinal barrier injury and the severity of pancreatitis. B lymphocytes infiltrated early in MAT, which might promote the MAT inflammation.

Visceral adipose tissue predicts severity and prognosis of acute pancreatitis in obese patients.

Acute pancreatitis is a common systemic inflammatory disease, manifested by a spectrum of severity, ranging from mild in the majority of patients to severe acute pancreatitis. Patients with severe acute pancreatitis suffer from severe local and systemic complications and organ failure, leading to a poor prognosis. The early recognition of the severe condition is important to improve prognosis. Obesity has risen in tandem with an increase in the severity of acute pancreatitis in recent years. Studies have revealed that adipose tissue, particularly visceral adipose tissue is associated with the prognosis of acute pancreatitis. This review discussed the role of visceral adipose tissue in obese patients with acute pancreatitis and explored the possible mechanism involved.

Risk factors associated with missed colorectal lesions in colonoscopy and impact of colonoscopy with anesthesia on miss rate.

OBJECTIVES: To systematically determine the miss rate and risk factors for polyps, adenomas and advanced adenomas in the same population, and to further analyze the impact of colonoscopy with anesthesia on miss rate. METHODS: We retrospectively analyzed the information of the patients undergoing the second colonoscopy within 1 year after their first. The patient and lesion miss rate were calculated. The patient and lesion features of missed lesion were compared with non-missed lesion. Finally, the patients were divided into anesthesia group and without anesthesia group, and the impact of colonoscopy with anesthesia on missed lesions was further analyzed. RESULTS: The patient miss rate of polyps, adenomas and advanced adenomas was 32.8, 25.6 and 10.4%, and the lesions miss rate was 19.6, 15.8 and 7.2%. In multivariable logistic regression analysis, lesion-related factors (large number of lesions, small lesion size, flat shape and location at the right colon) and patient-related factors (male, elder, abdominal symptoms, surgical history, diverticulum, colonoscopy without anesthesia and suboptimal bowel preparation) were found to be independently associated with missed polyps and adenomas (p < .05). Large number of lesions, flat shape and suboptimal bowel preparation were associated with missed advanced adenoma (p < .05). Colonoscopy with anesthesia can reduce the polyp miss rate (PMR) and male and elderly patients are more likely to be missed during colonoscopy without anesthesia. CONCLUSIONS: Many factors of patients and lesions can affect the lesions miss rate. Colonoscopy with anesthesia can reduce the PMR and male and elderly patients are more likely to be missed during colonoscopy without anesthesia.

Endoscopic management of iatrogenic gastrointestinal defects with the over-the-scope clip (OTSC) system: an updated systematic review.

BACKGROUND: Management of iatrogenic gastrointestinal (GI) defects traditionally required surgical interventions. Recently, the over-the-scope-clip system (OTSC) has been reported to be effective for GI defects. So we aimed to conduct an updated systematic review to evaluate the clinical safety and efficacy of the OTSC system for the management of iatrogenic GI defects. MATERIAL AND METHODS: Studies published in PubMed, Embase and Cochrane library from January 2006 to December 2018 were searched. The literature was selected independently by two reviewers according to inclusion and exclusion criteria. The statistical analysis was carried out using Comprehensive Meta-Analysis software version 3.0. RESULTS: A total of 12 studies including 191 patients with iatrogenic GI defects were identified. The major causes for iatrogenic GI defects were endoscopic submucosal dissection (n = 79) and endoscopic mucosal resection (n = 31). Pooled technical success was achieved in 182 patients (89.1%; 95% confidence interval (CI), 81.6%-93.8%, I2 =41.06%), and the pooled clinical success was achieved in 170 patients (85.2%; 95% CI, 71.9%-92.8%, I2=58.92%). Two patients (1%) suffered complications after OTSC system procedures. CONCLUSIONS: Our study revealed that endoscopic closure of iatrogenic GI defects by the OTSC system was a safe and effective approach. Further randomized controlled trials are warranted to compare the OTSC system to other treatment modalities.

The 100 top cited articles in the field of digestive endoscopy: from 1950 to 2017.

BACKGROUND: the present study aimed to describe the characteristics of articles that had the most citations in the field of digestive endoscopy. METHOD: articles included were obtained from the Web of Science database, which were selected and ranked according to the number of citations. The characteristics of the 100 most cited articles were then analyzed. RESULTS: the number of citations of the top 100 of 303,063 eligible papers ranged from 370 to 2,866. The most cited paper was a study of colorectal cancer prevention using colonoscopic polypectomy. The most common topics discussed by the top 100 papers included colonoscopy (n = 33) and upper gastrointestinal endoscopy (n = 23), with most of the papers focusing on diagnosis (n = 24) and treatment (n = 15). CONCLUSION: by identifying the most influential publications, the present study could serve as a guide toward further development in the area of digestive endoscopy.

Bibliometric analysis of the 100 most-cited articles in the field of hepatology.

OBJECTIVE: Bibliometric search of citation classics can function as a tool to identify extraordinary landmark articles and advanced research studies. We aimed to examine and characterize the 100 most-cited published articles in the field of hepatology. PATIENTS AND METHODS: A comprehensive list of the 100 most-cited articles published from 1950 to 2017 in the field of hepatology was compiled after searching the Web of Science with relevant terms, including "liver," "hepatitis," "hepatic," "hepatocellular," "hepatology," "cirrhosis," and "steatohepatitis." The articles were ranked according to their citation counts and were evaluated for characteristics including country, institution, authorship, publication year, subspecialty and others. RESULTS: The database search returned 323,291 articles associated with liver disease published between 1950 and 2017. The 100 most-cited articles were from 21 major journals, with the highest number of articles being published in Hepatology (n=20). The average number of citations of the 100 most-cited articles was 1946.8; among these articles, the most frequently cited article received 5515 citations, and the least frequently cited article received 1155 citations. In total, 60 were original articles among the 100 most-cited articles. The most frequently represented specialties were hepatitis, hepatocellular carcinoma, and nonalcoholic fatty liver disease, which accounted for 53.3%, 23.3%, and 11.7% of these articles, respectively. DISCUSSION: Our study identified citation classics and provided a review of the most advanced studies in the field of hepatology. This can help to guide clinical treatment and future academic research resulting in advancements in hepatology.

Peroral endoscopic shorter versus longer myotomy for the treatment of achalasia: a comparative retrospective study.

INTRODUCTION: Peroral esophageal myotomy (POEM) is a novel endoscopic treatment for achalasia. It has gained popularity worldwide among surgeons and endoscopists, but no studies have compared peroral endoscopic short with long myotomy for achalasia. We aimed to compare the clinical efficacy and safety between peroral endoscopic shorter and longer myotomy. METHODS: The retrospective study enrolled 129 achalasia patients who underwent POEM from July 2011 to September 2017. Based on the myotomy length (ML), patients were divided into shorter myotomy (SM) group (ML ≤ 7 cm, n = 36) and longer myotomy (LM) group (ML > 7 cm, n = 74). Procedure-related parameters, symptom scores, adverse events and manometric data were compared between two groups. RESULTS: The mean ML was 6.0 ± 0.6 cm in SM group, and 11.5 ± 3.1 cm in LM group (p < 0.001). The mean operation time was significantly less in SM group than LM group (46.6 ± 18.5 min vs 62.1 ± 25.2 min, p = 0.001). During a mean follow-up period of 28.7 months, treatment success (Eckardt score ≤ 3) was achieved in 94.4% (34/36) of patients in SM group and 91.9% (68/74) in LM group (p = 0.926). There was no statistical difference in the incidence of intraoperative complications (8.4% vs 8.2%, p = 0.823) and reflux rate (8.3% vs. 14.9%, p = 0.510) between two groups. CONCLUSIONS: Peroral endoscopic shorter myotomy is comparable with longer myotomy for treating achalasia with regard to clinical efficacy and has the advantage of shorter procedure time.

Efficacy and safety of submucosal tunneling endoscopic resection for upper gastrointestinal submucosal tumors with more than 1-year' follow-up: a systematic review and meta-analysis.

Objectives: Submucosal tunneling endoscopic resection (STER) is a novel therapeutic approach for upper gastrointestinal submucosal tumors (SMTs) especially for tumors originating from the muscularis propria layer. Presently, several studies have reported the efficacy and safety of STER for SMTs. Therefore, we conducted this study to review the clinical outcomes of STER with more than 1-year' follow-up duration. Materials and methods: Medline, Embase and Cochrane databases were searched on November 2018 to identify studies reporting STER for SMTs. Weighted pooled rates were calculated for en bloc resection, complete resection and adverse event (AE). Risk ratios (RR) were calculated and pooled to compare STER with thoracoscopic enucleation (TE). Results: A total of 701 patients with 728 lesions from 12 original studies were review. Pooled WPR for en bloc resection of STER was 86.3% (95% CI: 74.5-93.1%), (I2=82.5). Pooled WPR for complete resection of STER was 97.7% (95% CI: 92.8-99.3%), (I2=77.6). WPR for AE was 18.3% (95% CI: 9.7-31.6%), (I2=90.6%). Two studies with 292 patients compared the performance of STER with TE. Pooled RR for en bloc resection was 1.02 (95% CI: 0.95-1.09). Pooled RR for complete resection was 1.0 (95% CI: 0.98-1.03). Pooled RR for AE was 0.82 (95% CI: 0.33-2.05). Conclusions: Our study showed that STER has relatively long-term efficacy for treating upper gastrointestinal SMTs, and the incidence of AE was not low for STER, but all of them can be managed conservatively.

Clinical outcomes of over-the-scope-clip system for the treatment of acute upper non-variceal gastrointestinal bleeding: a systematic review and meta-analysis.

BACKGROUND: Conventional endoscopic treatments can't control bleeding in as many as 20% of patients with non-variceal gastrointestinal (GI) bleeding. Recent studies have shown that over-the-scope-clip (OTSC) system allowed for effective hemostasis for refractory GI bleeding lesions. So we aimed to conduct a systematic review to evaluate the effectiveness and safety of the OTSC system for management of acute non-variceal upper GI bleeding. METHOD: A comprehensive literature search was conducted on PubMed, EMBASE, and Cochrane Library covering the period from January 2007 to May 2019. The literature was selected independently by two reviewers according to the inclusion and exclusion criteria. The statistical analysis was carried out using Comprehensive Meta-Analysis software version 3.0. RESULTS: A total of 16 studies including 769 patients with 778 GI bleeding lesions were identified. Pooled technical success was achieved in 761 lesions [95.7%; 95% confidence interval (CI), 93.5-97.2%], and the pooled clinical success was achieved in 666 lesions (84.2, 95% CI, 77.4-89.2%). The incidence of re-bleeding was reported in 81 patients and the post-procedure mortality was 10.9% (n = 84). Only 2 (0.3%) patients occurred complications after OTSC system procedure. CONCLUSIONS: Our study demonstrated that the OTSC system was a technically feasible modality and highly efficacious in achieving hemostasis in acute non-variceal upper gastrointestinal bleeding.

Pre-treatment Eckardt score is a simple factor for predicting one-year peroral endoscopic myotomy failure in patients with achalasia.

BACKGROUND: Peroral endoscopic myotomy (POEM) is a novel treatment for achalasia with excellent outcomes. But the predictor for treatment failure is not well defined. This study was aimed to prospectively investigate the factors for predicting failed POEM. METHODS: From June 2011 to May 2015, a total of 115 achalasia patients treated by POEM were included for the retrospective cohort study from Nanfang Hospital and the First People's Hospital of Yunnan Province. Patients were followed up with Eckardt score, high-resolution manometry and endoscope. POEM failure was defined as primary failure (Eckardt score failed to decrease to 3 or below) and recurrences (decrease of Eckardt score to 3 or below, then rise to more than 3) during one-year follow-up. Univariate and multivariate Cox regression analyses were performed to assess the predictive factor. For the associated factor, receiver operating characteristic curve (ROC) was utilized to determine the cutoff value of the predicting factor. RESULTS: The failure rate of POEM after 1 year was 7.0% (8/115), including 5 primary failure cases and 3 recurrences. Multivariate analysis showed higher pre-treatment Eckardt score was the single independent factor associated with POEM failure [9.5 (6-12) vs. 7 (2-12), odds ratio (OR) 2.24, 95 confidence interval (95% CI) 1.39-3.93, p = 0.001]. The cutoff value (Eckardt score ≥9) had 87.5 sensitivity (95% CI 47.3-99.7%) and 73.8% specificity (95% CI 64.4-81.9%) for predicting failed POEM. CONCLUSIONS: Pre-treatment Eckardt score could be a predictive factor for failed POEM. Eckardt score ≥9 was associated with high sensitivity and specificity for predicting POEM failure.

Comparison of conventional versus Hybrid knife peroral endoscopic myotomy methods for esophageal achalasia: a case-control study.

OBJECTIVE: Peroral endoscopic myotomy (POEM) has been developed to treat achalasia as a novel less invasive modality. We aimed to compare the efficacy and safety of conventional knife versus Hybrid knife (HK) during POEM procedure. MATERIALS AND METHODS: Between June 2012 and July 2014, 31 patients underwent POEM using HK in our department (HK group), and 36 patients underwent POEM using conventional method (injection needle and triangular tip [TT] knife, TT group). Procedure-related parameters, symptom relief, adverse events were compared between two groups. RESULTS: There were no significant differences in the age, sex and other baseline characteristics between the two groups. The mean procedural time was significantly shorter in HK group than TT group (53.0 ± 17.2 vs. 67.6 ± 28.4 min, p = 0.015). The mean frequency of devices exchange was 4.7 ± 1.7 in HK group and 10.9 ± 1.8 in TT group (p = 0.000). No serious adverse events occurred postoperatively in both groups. At one-year follow-up, a total of 94% treatment success was achieved in all patients (93.5% in HK group and 94.4% in TT group, p = 0.877). CONCLUSION: HK in POEM can shorten the procedural time, and achieve similar treatment success compared to conventional TT knife.

Factors predicting the technical difficulty of peroral endoscopic myotomy for achalasia.

BACKGROUND: Peroral endoscopic myotomy (POEM) has been described as a novel treatment for esophageal achalasia. Owing to its technical difficulty, POEM is not widely performed. This study was aimed to prospectively assess the factor predicting technical difficulty of POEM in a single center with large volume cases. METHODS: A total of 105 cases of achalasia treated by POEM from April 2011 to September 2014 were analyzed. Difficult cases of POEM were defined as procedure time ≥90 min and occurrence of adverse events, including mucosal perforation, pneumothorax, and major bleeding. Univariate and multivariate logistic regression analyses were performed to assess the predictive factors of difficult POEM. RESULTS: POEM was successfully completed in all the patients, and no one was converted to laparoscopy. The number of cases with procedure time ≥90 min was 17. Mucosal perforations occurred in six (5.7 %) patients during submucosal tunnel creation, major bleeding occurred in seven (6.7 %) patients, and pneumothorax occurred in six (5.7 %) patients immediately after procedure. All the complications were managed conservatively. No other intraoperative and immediate postoperative complications, including infections and pneumoperitoneum, occurred. Multivariate analysis showed that early period (odds ratio [OR] 4.173, 95 % confidence interval [95 % CI] 1.36-6.829, P = 0.023) and triangular tip knife ([OR] 6.712, [95 % CI] 1.479-30.460, P = 0.014) were independent factors associated with technical difficulty regarding longer procedure time (procedure time ≥90 min). CONCLUSION: POEM is safe for the treatment of esophageal achalasia. Triangular tip knife and early period were independent risk factors for longer procedural time.

A stepwise approach for peroral endoscopic myotomy for treating achalasia: from animal models to patients.

OBJECTIVES: Peroral endoscopic myotomy (POEM) was initially developed for the treatment of achalasia. This study aimed to investigate the feasibility and safety of a stepwise approach for POEM in the management of achalasia. METHODS: A total of five ex-vivo porcine esophagus-stomach training models were created and POEM was performed. Then, 25 patients with achalasia were treated similarly. The Eckardt score, barium esophagrams, and high-resolution manometry were used to evaluate its efficacy. RESULTS: POEM procedures were completed in five stomach-esophagus models, with perforations in the initial three and success in the last two. A total of 25 achalasia patients (13 males, 12 females) with achalasia successfully underwent POEM. The mean operation time was 72.0 min (range, 45-180 min). There were two complications--one case each of severe bleeding and pneumothorax--that were both treated successfully. During the follow-up period, the median Eckardt score decreased dramatically from 8 to 1 (p = 0.000). The lower basal esophageal sphincter pressure decreased markedly (41.3 ± 12.6 vs. 11.3 ± 4.3 mmHg, p = 0.000), as well as the 4-s integrated relaxation pressure (37.1 ± 12.6 vs. 7.1 ± 2.4 mmHg, p = 0.000). Additionally, the maximum esophagus width was significantly reduced (mean reduced width: 1.6 ± 1.1 cm, p = 0.000). CONCLUSIONS: The ex-vivo porcine esophagus-stomach can be used as a simple and cheap training model that mimics the POEM procedure. POEM is a safe and effective therapy for achalasia patients.

Usefulness of peroral endoscopic myotomy for treating achalasia in children: experience from a single center.

INTRODUCTION: Achalasia is a rare esophageal motility disorder in the pediatric population. Peroral endoscopic myotomy (POEM) has been demonstrated to be effective and safe for the treatment of achalasia as a novel endoscopic technique, but data involving its utility in pediatric patients are limited. We aimed to assess the safety and efficacy of POEM for pediatric patients with achalasia. MATERIALS AND METHODS: Between July 2012 and August 2014, five consecutive pediatric patients (2 female and 3 male, with a median age of 15 years) with achalasia underwent POEM in our center. Diagnosis was based on symptoms, manometry, radiology and endoscopy. Preoperative and postoperative symptoms scores, and manometry outcomes were recorded and analyzed. RESULTS: Procedure was performed successfully in all patients, and the median time required for the procedure was 50 min (range 40-90 min). There were no mortalities and no serious intraoperative and postoperative complications. The median length of myotomy was 8 cm (range 6-11 cm). During a median follow-up period of 18 months, treatment success (Eckardt score ≤3) was achieved in all patients. There was a significant improvement of symptoms relief, dysphagia score and lower esophageal sphincter pressure decrease after POEM. No patient developed gastroesophageal reflux disease. CONCLUSION: Our study suggests that POEM is a safe and effective technique for treating pediatric achalasia. Further studies with long-term follow-up in large-volume pediatric patients are warranted to clearly define the durability of the procedure.

In vivo pilot study into superficial microcirculatory characteristics of colorectal adenomas using novel high-resolution magnifying endoscopy with blue laser imaging.

BACKGROUND: No studies have yet been conducted on changes in microcirculatory hemodynamics of colorectal adenomas in vivo under endoscopy. The microcirculation of the colorectal adenoma could be observed in vivo by a novel high-resolution magnification endoscopy with blue laser imaging (BLI), thus providing a new insight into the microcirculation of early colon tumors. AIM: To observe the superficial microcirculation of colorectal adenomas using the novel magnifying colonoscope with BLI and quantitatively analyzed the changes in hemodynamic parameters. METHODS: From October 2019 to January 2020, 11 patients were screened for colon adenomas with the novel high-resolution magnification endoscope with BLI. Video images were recorded and processed with Adobe Premiere, Adobe Photoshop and Image-pro Plus software. Four microcirculation parameters: Microcirculation vessel density (MVD), mean vessel width (MVW) with width standard deviation (WSD), and blood flow velocity (BFV), were calculated for adenomas and the surrounding normal mucosa. RESULTS: A total of 16 adenomas were identified. Compared with the normal surrounding mucosa, the superficial vessel density in the adenomas was decreased (MVD: 0.95 ± 0.18 vs 1.17 ± 0.28 µm/µm2, P < 0.05). MVW (5.11 ± 1.19 vs 4.16 ± 0.76 µm, P < 0.05) and WSD (11.94 ± 3.44 vs 9.04 ± 3.74, P < 0.05) were both increased. BFV slowed in the adenomas (709.74 ± 213.28 vs 1256.51 ± 383.31 µm/s, P < 0.05). CONCLUSION: The novel high-resolution magnification endoscope with BLI can be used for in vivo study of adenoma superficial microcirculation. Superficial vessel density was decreased, more irregular, with slower blood flow.