Background/Aims: We investigated how interactions between humans and computer-aided detection (CADe) systems are influenced by the user’s experience and polyp characteristics. Methods: We developed a CADe system using YOLOv4, trained on 16,996 polyp images from 1,914 patients and 1,800 synthesized sessile serrated lesion (SSL) images. The performance of polyp detection with CADe assistance was evaluated using a computerized test module. Eighteen participants were grouped by colonoscopy experience (nurses, fellows, and experts). The value added by CADe based on the histopathology and detection difficulty of polyps were analyzed. Results: The area under the curve for CADe was 0.87 (95% confidence interval [CI], 0.83 to 0.91). CADe assistance increased overall polyp detection accuracy from 69.7% to 77.7% (odds ratio [OR], 1.88; 95% CI, 1.69 to 2.09). However, accuracy decreased when CADe inaccurately detected a polyp (OR, 0.72; 95% CI, 0.58 to 0.87). The impact of CADe assistance was most and least prominent in the nurses (OR, 1.97; 95% CI, 1.71 to 2.27) and the experts (OR, 1.42; 95% CI, 1.15 to 1.74), respectively. Participants demonstrated better sensitivity with CADe assistance, achieving 81.7% for adenomas and 92.4% for easy-to-detect polyps, surpassing the standalone CADe performance of 79.7% and 89.8%, respectively. For SSLs and difficult-to-detect polyps, participants' sensitivities with CADe assistance (66.5% and 71.5%, respectively) were below those of standalone CADe (81.1% and 74.4%). Compared to the other two groups (56.1% and 61.7%), the expert group showed sensitivity closest to that of standalone CADe in detecting SSLs (79.7% vs 81.1%, respectively). Conclusions CADe assistance boosts polyp detection significantly, but its effectiveness depends on the user’s experience, particularly for challenging lesions.

Background/Aims: Combination of midazolam and opioids is used widely for endoscopic sedation. Compared with meperidine, fentanyl is reportedly associated with rapid recovery, turnover rate of endoscopy room, and quality of endoscopy. We compared fentanyl with meperidine when combined with midazolam for sedative colonoscopy. Methods: A retrospective, cross-sectional, 1:2 matching study was conducted. Induction and recovery time were compared as the primary outcomes. Moreover, cecal intubation time, withdrawal time, total procedure time of colonoscopy, paradoxical reaction, adenoma detection rate, and adverse effect of midazolam or opioids were assessed as the secondary outcomes. Results: A total of 129 subjects (43 fentanyl vs. 86 meperidine) were included in the analysis. The fentanyl group showed significantly more rapid induction time (4.5±2.7 min vs. 7.5±4.7 min, p<0.001), but longer recovery time (59.5±25.6 min vs. 50.3±10.9 min, p=0.030) than the meperidine group. In multivariate analysis, the induction time of the fentanyl group was 3.40 min faster (p<0.001), but the recovery time was 6.38 min longer (p=0.046) than that of the meperidine group. There was no difference in withdrawal time and adenoma detection rate between the two groups. Conclusions The fentanyl group had more rapid sedation induction time but longer recovery time than the meperidine group.

Background/Aims: Dietary fiber intake is considered a protective factor for diverticular disease such as diverticulitis. However, evidence for an inverse connection between dietary fiber consumption and asymptomatic colonic diverticulosis is lacking. Specifically, few studies have investigated this subject in Asians with different presentations of diverticulosis. Therefore, we assessed the protective effects of a vegetarian diet for asymptomatic colonic diverticulosis in Buddhist monks who are obligatory vegetarians for spiritual reasons compared with the general population. Methods: A retrospective, cross-sectional, case-control study was conducted in age- and sex-matched Buddhist monks and the general population who underwent colonoscopy for screening at a Korean health promotion center from August 2005 to June 2018. We compared the prevalence of asymptomatic diverticulosis between the 2 groups using a self-administered questionnaire. Results: In this study, a total of 1,316 individuals were included (Buddhist monks of 658 and general population of 658) with a mean age of 52.6±9.5 years. The prevalence of asymptomatic diverticulosis in Buddhist monks was lower compared with the general population (6.7% [44/658] vs. 10.8% [71/658], P=0.008). Buddhist monks had a higher rate of high body mass index (BMI) and metabolic syndrome. By a multivariate regression analysis model, a nonvegetarian diet (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.21–2.72, P=0.004), old age (OR, 4.53; 95% CI, 1.36–15.12; P=0.014), male sex (OR, 1.91; 95% CI, 1.28–2.85; P=0.002), and a high BMI (OR, 1.50; 95% CI, 1.01–2.23; P=0.047) were independent predictors of asymptomatic diverticulosis. Moreover, a nonvegetarian diet was associated with both right-sided and left-sided diverticulosis. Conclusions A nonvegetarian diet may increase a risk of asymptomatic colonic diverticulosis in Asians.

We report here the results of the external quality assessment scheme (EQA) of blood bank tests in Korea carried out in 2015. The proficiency testing specimens used in the survey were prepared at Ajou University Hospital. The response rates from participating laboratories for the first and second trials were 98.7% (542/549) and 98.2% (544/554), respectively. No answers to tests were considered incorrect, and the average accuracy rates for six different test items on the standard survey were as follows: ABO grouping, 99.4% to 100.0%; RhD typing, 99.4% to 100.0%; crossmatching, 93.6% to 99.0%; direct antiglobulin test (DAT) using a polyspecific reagent, 92.9% to 98.3%; DAT using an IgG monospecific reagent, 94.6% to 100.0%; DAT using a C3d monospecific reagent, 84.2% to 98.6%; unexpected antibody screening test, 94.5% to 100.0%; and antibody identification test, 93.8% to 100.0%. We performed a pilot survey on reactivities to A1 (54 responses) and H (50 responses); Rh C, c, E, and e antigen testing (47 responses); and ABO antibody titration (10-34 responses). We obtained excellent results for this EQA, and these results will be helpful for improving or maintaining the quality of the participating laboratories.
Blood Banks* ; Coombs Test ; Immunoglobulin G ; Korea* ; Laboratory Proficiency Testing ; Mass Screening

BACKGROUND: Arsenic is a carcinogenic heavy metal that has a species-dependent health effects and abandoned metal mines are a source of significant arsenic exposure. Therefore, the aims of this study were to analyze urinary arsenic species and their concentration in residents living near abandoned metal mines and to monitor the environmental health effects of abandoned metal mines in Korea. METHODS: This study was performed in 2014 to assess urinary arsenic excretion patterns of residents living near abandoned metal mines in South Korea. Demographic data such as gender, age, mine working history, period of residency, dietary patterns, smoking and alcohol use, and type of potable water consumed were obtaining using a questionnaire. Informed consent was also obtained from all study subjects (n = 119). Urinary arsenic species were quantified using high performance liquid chromatography (HPLC) and inductively coupled plasma mass spectrometry (ICP/MS). RESULTS: The geometric mean of urinary arsenic (sum of dimethylarsinic acid, monomethylarsonic acid, As3+, and As5+) concentration was determined to be 131.98 μg/L (geometric mean; 95% CI, 116.72–149.23) while urinary inorganic arsenic (As3+ and As5+) concentration was 0.81 μg/L (95% CI, 0.53–1.23). 66.3% (n = 79) and 21.8% (n = 26) of these samples exceeded ATSDR reference values for urinary arsenic (>100 μg/L) and inorganic arsenic (>10 μg/L), respectively. Mean urinary arsenic concentrations (geometric mean, GM) were higher in women then in men, and increased with age. Of the five regions evaluated, while four regions had inorganic arsenic concentrations less than 0.40 μg/L, one region showed a significantly higher concentration (GM 15.48 μg/L; 95% CI, 7.51–31.91) which investigates further studies to identify etiological factors. CONCLUSION: We propose that the observed elevation in urinary arsenic concentration in residents living near abandoned metal mines may be due to environmental contamination from the abandoned metal mine. TRIAL REGISTRATION: Not Applicable (We do not have health care intervention on human participants).
Arsenic* ; Cacodylic Acid ; Chromatography, Liquid ; Delivery of Health Care ; Drinking Water ; Environmental Health ; Female ; Humans ; Informed Consent ; Internship and Residency ; Korea* ; Male ; Mass Spectrometry ; Plasma ; Reference Values ; Smoke ; Smoking

PURPOSE: This study was to evaluate the effects of bacterial cellulose (BC) membranes as a barrier membrane on guided bone regeneration (GBR) in comparison with those of the resorbable collagen membranes. MATERIALS AND METHODS: BC membranes were fabricated using biomimetic technology. Surface properties were analyzed, Mechanical properties were measured, in vitro cell proliferation test were performed with NIH3T3 cells and in vivo study were performed with rat calvarial defect and histomorphometric analysis was done. The Mann-Whitney U test and the Wilcoxon signed rank test was used (alpha<.05). RESULTS: BC membrane showed significantly higher mechanical properties such as wet tensile strength than collagen membrane and represented a three-dimensional multilayered structure cross-linked by nano-fibers with 60 % porosity. In vitro study, cell adhesion and proliferation were observed on BC membrane. However, morphology of the cells was found to be less differentiated, and the cell proliferation rate was lower than those of the cells on collagen membrane. In vivo study, the grafted BC membrane did not induce inflammatory response, and maintained adequate space for bone regeneration. An amount of new bone formation in defect region loaded with BC membrane was significantly similar to that of collagen membrane application. CONCLUSION: BC membrane has potential to be used as a barrier membrane, and efficacy of the membrane on GBR is comparable to that of collagen membrane.
Animals ; Biomimetics ; Bone Regeneration* ; Cell Adhesion ; Cell Proliferation ; Cellulose* ; Collagen* ; Membranes* ; Osteogenesis ; Porosity ; Rats ; Surface Properties ; Tensile Strength ; Transplants

BACKGROUND/AIMS: Gallbladder polyps (GBP) are a common clinical finding that can express malignant potential. The aim of this study was to evaluate whether vegetarianism protects against GBP, together with other putative risk factors. METHODS: A retrospective, cross-sectional study was conducted with subjects who received a health check-up from July 2005 to December 2011. Korean Buddhist priests, who are obligatory vegetarians by religious belief, were identified as vegetarians (vegetarian group) and compared with a non-vegetarian control group sampled from those coming for health check-ups at the same institution. RESULTS: Out of 18,483 subjects, GBP were found in 810 (4.4%). Although GBP tended to be less common in the vegetarian group (23 [3.5%] out of 666) than in control group (787 [4.4%] out of 17,817), the difference was insignificant statistically (p=0.233). By logistic regression, old age (OR=1.61, 95% CI=1.19-2.26 for 30-39 years; OR=1.47, 95% CI=1.08-1.98 for 40-49 years), male gender (OR=1.51, 95% CI=1.31-1.75), high BMI (OR=1.18, 95% CI=1.00-1.39 for > or =23.0 kg/m2 and <25.0 kg/m2) and HBsAg positivity (OR=1.53, 95% CI=1.19-1.98) were independent risk factors of GBP. CONCLUSIONS: GBP was significantly associated with old age, male gender, high BMI and HBsAg positivity, but not with vegetarianism.
Adult ; Age Factors ; Aged ; Body Mass Index ; Cross-Sectional Studies ; Female ; Gallbladder Diseases/diagnosis/*epidemiology ; Humans ; Logistic Models ; Male ; Middle Aged ; Odds Ratio ; Polyps/*epidemiology/pathology ; Prevalence ; Retrospective Studies ; Risk Factors ; Sex Factors ; Vegetarians

OBJECTIVE: The purpose of this study is to examine the difference between the numbers of patients in rheumatoid arthritis (RA) who are eligible to TNF inhibitors by the past Korean National Health Insurance reimbursement guideline and by the disease activity score with 28-joint assessment (DAS28) based criteria. METHODS: Data were obtained from a multi-center registry for biologics users in Korean RA patients, BIOlogics Pharmacoepidemiologic StudY (BIOPSY). DAS28 was calculated based on either ESR or CRP, and DAS28 of more than 5.1 or between 3.2 and 5.1 with radiographic changes was defined as a cut-off point for the initiation of TNF inhibitors. For the maintenance criteria, we used both of improving in DAS28 score (>1.2) and low disease activity (DAS 28<3.2). Differences between the numbers in each step by two criteria were described with Chi-square test and Kappa agreement. RESULTS: Of the 489 patients in BIOPSY, 299 were included in this study. Among them, 278 patients (93.0%) were eligible of TNF inhibitors when we applied the new initiation criteria with DAS28-ESR, and 244 patients (81.6%) were indicated for TNF inhibitors with DAS28-CRP. For the maintenance criteria, a low disease activity (DAS28<3.2) in 3 months after starting TNF inhibitors is too strict for achieving (33.6% with DAS28-ESR and 50.0% with DAS28-CRP). Instead, decreasing DAS28 by more than 1.2 is more reasonable as a tool for deciding early responsiveness of TNF inhibitors in RA patients (81.2% both with DAS28-ESR and DAS28-CRP). CONCLUSION: Our results show that the candidates for TNF inhibitors will be enormously changed according to a change in the reimbursement criteria. To define appropriate patients to receive TNF inhibitors, a further study with regard to the impact of changes in the reimbursement criteria on the outcomes of RA patients will be required.
Arthritis, Rheumatoid ; Biological Products ; Biopsy ; Humans ; National Health Programs

Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurrent episodes of fever and serosal, synovial, or cutaneous inflammation, caused by a dysfunction of pyrin as a result of mutation within the MEFV gene. It occurs mainly among Mediterranean and Middle Eastern populations, including Jews, Arabs, and Turks. However, FMF cases have been reported outside the Mediterranean and Middle Eastern countries in recent years. Although FMF has been relatively rare in Korea until now, proper recognition of FMF might lead to more frequent diagnoses of FMF. We experienced an interesting case, a 31-year-old Korean man who presented with recurrent abdominal pain with fever and urticarial eruption for 10 years. DNA analysis showed complex mutations (p.Leu110Pro, p.Glu148Gln) in the MEFV gene. To date, three cases have been reported, and this case of FMF with skin conditions is the first case in Korea.
Abdominal Pain/*etiology ; Adult ; Base Sequence ; Cytoskeletal Proteins/genetics ; Familial Mediterranean Fever/complications/*diagnosis/genetics ; Humans ; Male ; Polymorphism, Single Nucleotide ; Recurrence ; Sequence Analysis, DNA ; Urticaria/*diagnosis

BACKGROUND/AIMS: Proton pump inhibitor (PPI) is generally prescribed to prevent post endoscopic submucosal dissection (ESD) bleeding. However, there was no consensus about the effectiveness of intravenous (IV) or oral PPI. We conducted this investigation to evaluate whether oral PPI can be also safely and effectively used to prevent post-ESD bleeding by measurement of intragastric pH. MATERIALS AND METHODS: Patients were assigned in the fixed order to IV pantoprazole by 40 mg every 12 hours and oral lansoprazole fast disintegrating tablet (LFDT) by 30 mg every 8 hours. We checked intragastric pH and hemoglobin (Hb) levels at pre and post-ESD procedure. RESULTS: A total of 10 patients (LFDT group: 6 patients, IV pantoprazole group: 4 patients) were included. There was no difference of baseline Hb level between two groups (LFDT, 14.38+/-0.46 mg/dL; IV pantoprazole, 13.85+/-0.83 mg/dL; P=0.18). After 24 hours, change of Hb level was not different between LFDT (0.95+/-0.30 mg/dL) and IV pantoprazole group (0.98+/-0.45 mg/dL; P=0.96). Baseline intragastric pH was 3.72+/-0.19 with LFDT and 4.31+/-0.41 with IV pantoprazole group (P=0.18). After 24 hours, there was no significant difference of the extent of pH increase between LFDT (2.38+/-0.28) and IV pantoprazole group (2.17+/-0.21; P=0.60). CONCLUSIONS: There was no difference in both the increase of post-24 hour intragastric pH and decrease of post-24 hour Hb between LFDT and IV pantoprazole group. Oral PPI regimen may be able to replace IV PPI therapy for the prevention of post-ESD bleeding and LFDT might be superior to IV PPIs in the aspect of cost-effectiveness.
Consensus ; Hemorrhage* ; Humans ; Hydrogen-Ion Concentration ; Lansoprazole* ; Proton Pump Inhibitors ; Proton Pumps