• Clinical Endoscopy
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• v.55 no.6
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• pp.767-774
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• 2022

Background/Aims: Few studies have compared the performances of endoscopic knives. This study aimed to compare the therapeutic outcomes of a novel core knife and the conventional IT knife 2 for endoscopic submucosal dissection (ESD) of gastric mucosal lesions. Methods: This prospective, non-inferiority trial included patients diagnosed with gastric adenoma or early-stage adenocarcinoma at Keimyung University Dongsan Hospital between June and November 2020. The patients were randomly assigned to either the core knife or the IT knife 2 group. The operators and assistants scored the knives' grip convenience and cutting abilities. Results: A total of 39 patients were enrolled (core knife group, 20 patients; IT knife 2 group, 19 patients). There were no significant between-group differences in operator-assessed grip convenience (9.600 vs. 9.526, p=0.753), cutting ability (9.600 vs. 9.105, p=0.158), or assistant-assessed grip convenience (9.500 vs. 9.368, p=0.574). Conclusions: The core knife achieved therapeutic outcomes that were comparable to those of the IT knife 2 for ESD of gastric mucosal lesions.

• Clinical Endoscopy
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• v.55 no.4
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• pp.525-531
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• 2022

Background/Aims: Endoscopic wound suturing is an important factor that affects the ability to remove large and full-thickness lesions during endoscopic resection. We aimed to evaluate the effect of a traction metal clip with a fishhook-like device on wound sutures after endoscopic resection. Methods: From July 2020 to April 2021, patients who met the enrollment criteria were treated with a fishhook-like device during the operation to suture the postoperative wound (group A). Patients with similar conditions and similar size wounds who were treated with a "purse-string suture" to suture the wounds were retrospectively analyzed as the control group (group B). Difference in the suture rate, adverse events, time required for suturing, and number of metal clips were compared between the two groups. Results: The time required for suturing was 7.72±0.51 minutes in group A and 11.50±0.91 minutes in group B. This difference was statistically significant (F=13.071, p=0.001). The number of metal clamps used in group A averaged 8.1 pieces/case, and the number of metal clamps used in group B averaged 7.3 pieces/case. This difference was not statistically significant (F=0.971, p=0.331). Conclusions: The traction metal clip with the fishhook-like device is ingeniously designed and easy to operate. It has a good suture effect on the wound after endoscopic submucosal dissection and effectively prevents postoperative adverse events.

• Clinical Endoscopy
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• v.55 no.6
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• pp.793-800
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• 2022

Background/Aims: Fully covered self-expanding metal stents (FCSEMSs) are a relatively novel option for treating painful main pancreatic duct refractory strictures in patients with chronic pancreatitis. Herein, we aimed to assess the efficacy, feasibility, and safety of FCSEMSs in this patient group. Methods: This prospective single-center study included patients who underwent endoscopic retrograde pancreatography with FCSEMS placement. The primary endpoints were the technical and clinical success rates. A reduction in visual analog scale pain score of >50% compared with that before stent placement was defined as clinical success. Secondary endpoints were resolution of pancreatic strictures on fluoroscopy during endoscopic retrograde pancreatography and the development of stent-related adverse events. Results: Thirty-six patients were included in the analysis. The technical success rate was 100% (n=36) and the clinical success rate was 86.1% (n=31). There was a significant increase in stricture diameter from 1.7 mm to 3.5 mm (p<0.001) after stent removal. The mean visual analog scale pain score showed statistically significant improvement. At 19 months of follow-up, 55.6% of the patients were asymptomatic. Stent migration (16.7%), intolerable abdominal pain (8.3%), development of de novo strictures (8.3%), and mild pancreatitis (2.8%) were the most common adverse events. Conclusions: FCSEMS placement showed good technical and clinical success rates for achieving pain relief in patients with refractory main pancreatic duct strictures.

• Clinical Endoscopy
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• v.55 no.5
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• pp.637-644
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• 2022

Background/Aims: Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is integral to the diagnosis of gastrointestinal (GI) subepithelial tumors (SETs). The impact of different EUS-FNB tissue sampling techniques on specimen adequacy and diagnostic accuracy in SETs has not been fully evaluated. This study aimed to compare the diagnostic outcomes of slow-pull (SP) and standard suction (SS) in patients with GI SETs. Methods: In this retrospective comparative study, 54 patients were enrolled. Medical records were reviewed for location and size of the target lesion, FNB needle type/size, technical order, specimen adequacy, diagnostic yield, and adverse events. The acquisition rate of adequate specimens and diagnostic accuracy were compared according to EUS-FNB techniques. Results: The mean lesion size was 42.6±36.4 mm, and most patients were diagnosed with GI stromal tumor (75.9%). The overall diagnostic accuracies of the SP and SS techniques were 83.3% and 81.5%, respectively (p=0.800). The rates of obtaining adequate core tissue were 79.6% and 75.9%, respectively (p=0.799). No significant clinical factors affected the rate of obtaining adequate core tissue, including lesion location and size, FNB needle size, and final diagnosis. Conclusions: SP and SS had comparable diagnostic accuracies and adequate core tissue acquisition for GI SETs via EUS-FNB.

• Clinical Endoscopy
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• v.55 no.5
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• pp.645-654
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• 2022

Background/Aims: Narrow Band Imaging (NBI) International Colorectal Endoscopic (NICE) and Workgroup Serrated Polyps and Polyposis (WASP) classifications were developed for optical diagnosis of neoplastic and sessile serrated polyps, respectively. Near-focus NBI with NICE combined with WASP criteria for optical diagnosis of colonic polyps has not yet been evaluated. We aimed to compare the accuracy of near-focus NBI (group A) with normal-focus NBI (group B) in real-time optical diagnosis of colorectal polyps using combined NICE and WASP criteria. Methods: Among 362 patients, 118 with 227 polyps were recruited. Groups A and B included 62 patients with 130 polyps (three lost polyps) and 56 patients with 106 polyps (six lost polyps), respectively. Optical diagnoses were compared with pathological reports. Results: The accuracy of optical diagnosis of neoplastic polyps in groups A and B was not significantly different (76% vs. 71%, p=0.52). WASP criteria provided all false positive diagnoses of sessile polyps as serrated polyps in 31 (16.2%) patients. Conclusions: Near-focus NBI was not superior to normal-focus NBI in optical diagnostics of neoplastic polyps using NICE criteria. In our study, WASP classification yielded all false positives in the diagnosis of sessile serrated adenomas/polyps. Routine real-life optical diagnosis of polyps is still unadvisable.

• Clinical Endoscopy
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• v.55 no.5
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• pp.674-682
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• 2022

Background/Aims: Endoscopic channels are difficult to clean and can cause infection transmission. We examined the effectiveness of a newly developed channel-cleaning ball brush (BB), which is sucked into the endoscopic channel and scrapes and cleans the lumen as it passes through. Methods: The upper and lower gastrointestinal endoscopes used for patient examinations were randomly selected as the conventional brush (CB) or BB group. After manual cleaning, the presence or absence of carbohydrates, proteins, adenosine triphosphate, and hemoglobin was assessed. Results: Fifty-six and 58 endoscopes were cleaned with the CB and BB, respectively. Carbohydrate and protein were detected in one (1.8%) and two endoscopes (3.4%) in the CB and BB groups, respectively (p=1.000). Hemoglobin was observed in one (1.8%) and three endoscopes (5.2%) in the CB and BB groups, respectively (p=0.636). The adenosine triphosphate levels were 10.6±15.9 and 12.5±14.3 relative light units in the CB and BB groups, respectively (p=0.496). Twenty-seven (48.2%) and 19 (32.8%) endoscopes were positive for microbial cultures in the CB and BB groups, respectively (p=0.136). Conclusions: The efficacy of BB was not significantly different from that of CB in the endoscopic channel-cleaning process.

• Clinical Endoscopy
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• v.55 no.1
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• pp.113-121
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• 2022

Background/Aims: We have been developing artificial intelligence based polyp histology prediction (AIPHP) method to classify Narrow Band Imaging (NBI) magnifying colonoscopy images to predict the hyperplastic or neoplastic histology of polyps. Our aim was to analyze the accuracy of AIPHP and narrow-band imaging international colorectal endoscopic (NICE) classification based histology predictions and also to compare the results of the two methods. Methods: We studied 373 colorectal polyp samples taken by polypectomy from 279 patients. The documented NBI still images were analyzed by the AIPHP method and by the NICE classification parallel. The AIPHP software was created by machine learning method. The software measures five geometrical and color features on the endoscopic image. Results: The accuracy of AIPHP was 86.6% (323/373) in total of polyps. We compared the AIPHP accuracy results for diminutive and non-diminutive polyps (82.1% vs. 92.2%; p=0.0032). The accuracy of the hyperplastic histology prediction was significantly better by NICE compared to AIPHP method both in the diminutive polyps (n=207) (95.2% vs. 82.1%) (p<0.001) and also in all evaluated polyps (n=373) (97.1% vs. 86.6%) (p<0.001) Conclusions: Our artificial intelligence based polyp histology prediction software could predict histology with high accuracy only in the large size polyp subgroup.

• Clinical Endoscopy
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• v.55 no.2
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• pp.256-262
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• 2022

Background/Aims: The diagnosis of intestinal tuberculosis (ITB) is often challenging. Therapeutic anti-tubercular trial (TATT) is sometimes used for the diagnosis of ITB. We aimed to evaluate the changing pattern of fecal calprotectin (FC) levels during TATT in patients with ITB. Methods: A retrospective review was performed on the data of 39 patients who underwent TATT between September 2015 and November 2018 in five university hospitals in Daegu, South Korea. The analysis was performed for 33 patients with serial FC measurement reports. Results: The mean age of the participants was 48.8 years. The final diagnosis of ITB was confirmed in 30 patients based on complete mucosal healing on follow-up colonoscopy performed after 2 months of TATT. Before starting TATT, the mean FC level of the ITB patients was 170.2 ㎍/g (range, 11.5-646.5). It dropped to 25.4 ㎍/g (range, 11.5-75.3) and then 23.3 ㎍/g (range, 11.5-172.2) after one and two months of TATT, respectively. The difference in mean FC before and one month after TATT was statistically significant (p<0.001), and FC levels decreased to below 100 ㎍/g in all patients after one month of TATT. Conclusions: All ITB patients showed FC decline after only 1 month of TATT, and this finding correlated with complete mucosal healing in the follow-up colonoscopy after 2 months of TATT.

• Clinical Endoscopy
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• v.55 no.3
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• pp.372-380
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• 2022

Background/Aims: Endoscopic resection has become the preferred treatment approach for select early esophageal adenocarcinoma (EAC); however, the epidemiology of early stage disease has not been well defined. Methods: Surveillance Epidemiology and End Results (SEER) data were analyzed to determine age-adjusted incidence rates among major epithelial carcinomas, including EAC, from 1973 to 2017. The percent change in incidence over time was compared according to tumor subtype. Early T-stage, node-negative EAC without metastasis was examined from 2004 to 2017 when precise T-stage data were available. Results: The percent change in annual incidence from 1973 to 2017 was 767% for EAC. Joinpoint analysis showed that the average annual percent change in EAC from 1973 to 2017 was 5.11% (95% confidence interval, 4.66%-5.56%). The annual percent change appeared to plateau between 2004 and 2017; however, early EAC decreased from 2010 to 2017, with an annual percent change of -5.78%. Conclusions: There has been a 7-fold increase in the incidence of EAC, which was significantly greater than that of the other major epithelial malignancies examined. More recently, the incidence of early EAC has been decreasing. Approximately one in five patients has node negative, potentially resectable early stage disease.

• Clinical Endoscopy
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• v.55 no.2
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• pp.263-269
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• 2022

Background/Aims: Difficult biliary cannulation is an important risk factor for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). Therefore, this study aimed to identify the factors that predict difficult cannulation for common bile duct stones (CBDS) to reduce the risk for PEP. Methods: This multicenter retrospective study included 1,406 consecutive patients with native papillae who underwent ERCP for CBDS. Factors predicting difficult cannulation for CBDS were identified using univariate and multivariate analyses. Results: Univariate analysis showed that six factors significantly predicted difficult cannulation: ERCP performed by non-expert endoscopists, low-volume center, absence of acute cholangitis, normal serum bilirubin, intradiverticular papilla, and type of major duodenal papilla. Multivariate analysis identified ERCP performed by non-expert endoscopists (odds ratio [OR], 2.5; p<0.001), low-volume center (OR, 1.6; p<0.001), intradiverticular papilla (OR, 1.3; p=0.007), normal serum bilirubin (OR, 1.3; p=0.038), and absence of acute cholangitis (OR, 1.3; p=0.049) as factors significantly predicting difficult cannulation for CBDS. Conclusions: Initial cannulation by an experienced endoscopist, early rescue cannulation, or early takeover by an experienced endoscopist should be considered when performing ERCP for CBDS in the presence of factors predicting difficult cannulation.