Efficacy of adjuvant mitomycin-C and triamcinoloneimpregnated nasal packing for endoscopic dacryocystorhinostomy

●AIM:To compare the success rate and complications of adjuvant use of mitomycin C and triamcinoloneimpregnated biodegradable nasal packing(TABP)in endoscopic dacryocystorhinostomy(DCR).And to evaluate the efficacy of combining intraoperative mitomycin C and TABP for endoscopic DCR.●METHODS:A total of 198 eyes of 148 patients who underwent endoscopic DCR for acquired nasolacrimal duct obstruction were retrospectively analysed.The patients were randomly divided into three groups:Group A included patients treated without intraoperative mitomycin C but with TABP,Group B included patients treated without triamcinolone but with intraoperative mitomycin C and normal saline-impregnated nasal packing,and Group C included patients treated with intraoperative mitomycin C and TABP.●RESULTS:The results revealed no significant difference in the overall success rates between Groups A(86.8%)and B(89.2%;P=0.377).However,Group C(97.5%)showed a significantly higher overall success rate than Groups A and B.The incidence of granulomas was significantly lower in group C(5%)than in Groups A(20.8%)and B(15.2%;P=0.009).Other complications,such as crust,synechiae,and revision surgery,did not differ significantly among the three groups.●CONCLUSION:The combination of intraoperative mitomycin C and TABP effectively prevents granulomas and enhances surgical success rate.Additionally,there is no statistically significant difference observed between the use of mitomycin C or TABP alone.

Surgical Repair of Ventricular Septal Defect in Neonates: Indications and Outcomes

Background:The optimal surgical timing and clinical outcomes of ventricular septal defect(VSD)closure in neo-nates remain unclear.We aimed to evaluate the clinical outcomes of VSD closure in neonates(age≤30 days).Methods:We retrospectively reviewed 50 consecutive neonates who underwent VSD closure for isolated VSDs between August 2003 and June 2021.Indications for the procedure included congestive heart failure/failure to thrive and pulmonary hypertension.Major adverse events(MAEs)were defined as the composite of all-cause mortality,reoperation,persistent atrioventricular block,and significant(≥grade 2)valvular dysfunction.Results:The median age and body weight at operation were 26.0 days(interquartile range[IQR],18.8–28.3)and 3.7 kg(IQR,3.3–4.2),respectively.The median follow-up duration was 110.4 months(IQR,56.8–165.0).Seven patients required preoperative respiratory support,andfive had significant(≥grade 2)preoperative valvular dysfunction.One early mortality occurred due to irreversible cardiogenic shock;no late mortality was observed.One reopera-tion was due to hemodynamically significant residual VSD at 103.8 months postoperatively.The overall survival,freedom from reoperation,and freedom from MAE at 15-years were 98.0%,96.3%,and 94.4%,respectively.Pre-operative mechanical ventilation was associated with a longer duration of postoperative mechanical ventilation(p<0.001)and a longer length of intensive care unit stay(p<0.001).Conclusions:VSD closure with favorable outcomes without morbidities is feasible even in neonates.However,neonates requiring preoperative respiratory support may require careful postoperative management considering the long-term postoperative risks.Overall,surgical VSD closure might be indicated earlier in neonates with respiratory compromise.

Efficacy and safety of limited endoscopic sphincterotomy before self-expandable metal stent insertion for malignant biliary obstruction

To evaluate the safety and efficacy of limited endoscopic sphincterotomy (ES) before placement of self-expandable metal stent (SEMS).METHODSThis was a retrospective analysis of 244 consecutive patients with unresectable malignant biliary obstruction, who underwent placement of SEMSs following limited ES from December 2008 to February 2015. The diagnosis of malignant biliary obstruction and assessment of patient eligibility for the study was established by a combination of clinical findings, laboratory investigations, imaging and pathological results. All patients were monitored in the hospital for at least 24 h following endoscopic retrograde cholangio pancreatography (ERCP). The incidence of immediate or early post-ERCP complications such as post-ERCP pancreatitis (PEP) and bleeding related to limited ES were considered as primary outcomes. Also, characteristics and complications according to the cancer type were classified.RESULTSAmong the 244 patients included, the underlying diagnosis was cholangiocarcinoma in 118 patients, pancreatic cancer in 79, and non-pancreatic or non-biliary malignancies in the remaining 47 patients. Early post-ERCP complications occurred in 9 patients (3.7%), with PEP in 7 patients (2.9%; mild, 6; moderate, 1) and mild bleeding in 2 patients (0.8%). There was no significant association between the incidence of post-ERCP complications and the type of malignancy (cholangiocarcinoma vs pancreatic cancer vs others, P = 0.696) or the type of SEMS used (uncovered vs covered, P = 1.000). Patients who had more than one SEMS placed at the first instance were at a significantly higher risk of post-ERCP complications (one SEMS vs two SEMS, P = 0.031). No other factors were predictive of post-ERCP complications.CONCLUSIONLimited ES is feasible and safe, and effectively facilitates the placement of SEMS, without any significant risk of PEP or severe bleeding.

Real-world utility of serological tests in patients with suspected scrub typhus in the Republic of Korea:A single-center,retrospective,observational study

Objective:Serological tests are widely used for scrub typhus diagnosis;however,their limitations are evident.This study aims to assess their practical value in clinical settings.Methods:We analyzed the data of adult patients with suspected scrub typhus who visited a tertiary care hospital in the Republic of Korea from September to December from 2019 to 2021.The included patients had an acute fever and at least one of the following ten secondary findings:myalgia,skin rash,eschar,headache,thrombocytopenia,increased liver enzyme levels,lymphadenopathy,hepatomegaly,splenomegaly,and pleural effusion.The diagnoses were grouped as scrub typhus or other diseases by two infectious disease physicians.Results:Among 136 patients who met the eligibility criteria,109 had scrub typhus and 27 had different diseases.Single and paired total antibodies using immunofluorescence assay(IFA),and total antibodies using immunochromatography-based rapid diagnostic testing(ICT)were measured in 98%,22%,and 75%of all patients,respectively.Confirmation using paired samples for scrub typhus was established at a median of 11[interquartile range(IQR)10-16]days following the first visit.Among the 82 admitted patients,the median admission time was 9(IQR 7-13)days.According to IFA,58(55%)patients with scrub typhus had total immunoglobulin titers≥1:320,while 23(85%)patients with other disease had titers<1:320.Positive ICT results were observed in 64(74%)patients with scrub typhus and 10(67%)patients with other diseases showed negative ICT results.Conclusions:Serological testing for scrub typhus is currently insufficient for decision-making in clinical practice.

Clinicopathologic significance of expression of nuclear factor-kB RelA and its target gene products in gastric cancer patients

AIM:To assess the prognostic significance of nuclear factor-kB (NF-kB) and its target genes in gastric cancer. METHODS:The tumor tissues of 115 patients with gastric cancer were immunohistochemically evaluated using monoclonal antibodies against NF-kB RelA. Preoperative serum levels of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6) were assessed via enzyme-linked immuno-sorbent assay. C-reactive protein (CRP) and serum amyloid A (SAA) were measured via immunotrubidimetry. RESULTS:Positive rate of NF-kB RelA was 42.6%. NF-kB RelA expression in tumor tissues was also related to serum levels of IL-6 (P = 0.044) and CRP (P = 0.010). IL-6, SAA, CRP were related to depth of invasion, VEGF and SAA were correlated with lymph node metastasis. IL-6, VEGF, SAA and CRP were related to the stage. Univariate analysis demonstrated that immunostaining of NF-kB RelA, levels of IL-6, VEGF, SAA were significantly related with both disease free survival and over-all survival (OS). Multivariate analysis verified that NF-kB RelA [hazard ratio (HR): 3.40, P = 0.024] and SAA (HR: 3.39, P = 0.045) were independently associated with OS. CONCLUSION: Increased expression of NF-kB RelA and high levels of serum SAA were associated with poor OS in gastric cancer patients.

Efficacy of cap-assisted colonoscopy according to lesion location and endoscopist training level

AIM: To evaluate the efficacy of cap-assisted colonoscopy(CAC) for detection of colorectal polyps and adenomas according to the lesion location and endoscopist training level.METHODS: Patients 20 years or older, who underwent their first screening colonoscopy in a single tertiary center from May 2011 to December 2012 were enrolled in this study. All patients underwent either CAC or standard colonoscopy(SC), and all of the procedures were performed by 11 endoscopists(8 trainees and 3 experts). All procedures were performed with highdefinition colonoscopes and narrow band imaging. The eight trainees had experiences of performing 150 to 500 colonoscopies, and the three experts had experiences of performing more than 3000 colonoscopies. A 4-mmlong transparent cap was attached to the end of a colonoscope in the CAC group. We retrospectively evaluated the number of polyps and adenomas, polyp detection rate(PDR), and the number of adenomas and adenoma detection rate(ADR) according to the lesion location and endoscopist training level between CAC and SC. We also evaluated the number of polyps and adenomas according to their size between CAC and SC.RESULTS: Overall, PDR and ADR using CAC were significantly higher than those using SC for both whole colon(48.5% vs 40.7%, P = 0.012; 35.7% vs 28.3%, P = 0.012) and right-side colon(35.3% vs 26.6%, P = 0.002; 27.0% vs 16.9%, P < 0.001). The number of polyps and adenomas per patient using CAC was significantly higher than that using SC for both the whole colon(1.07 ± 1.59 vs 0.82 ± 1.31, P = 0.008; 0.72 ± 1.32 vs 0.50 ± 1.01, P = 0.003) and right-side colon(0.66 ± 1.18 vs 0.41 ± 0.83, P < 0.001; 0.46 ± 0.97 vs 0.25 ± 0.67, P < 0.001). In the trainee group, the PDR and ADR using CAC were significantly higher than those using SC for both the whole colon(46.7% vs 39.7%, P = 0.040; 33.9% vs 26.0%, P =0.012) and right-side colon(34.2% vs 26.5%, P = 0.015; 25.3% vs 15.9%, P = 0.001). In the expert group, the PDR and ADR using CAC were significantly higher than those using SC only for the right-side colon(42.1% vs 27.0%, P =0.035; 36.8% vs 21.0%, P = 0.020).CONCLUSION: CAC is more effective than SC for detection of colorectal polyps and adenomas, especially when performed by trainees and when the lesions are located in the right-side colon.

Is endoscopic ultrasonography essential for endoscopic resection of small rectal neuroendocrine tumors?

AIM To evaluate the importance of endoscopic ultrasonography(EUS) for small(≤ 10 mm) rectal neuroendocrine tumor(NET) treatment.METHODS Patients in whom rectal NETs were diagnosed by endoscopic resection(ER) at the Pusan National University Yangsan Hospital between 2008 and 2014 were included in this study. A total of 120 small rectal NETs in 118 patients were included in this study. Histologic features and clinical outcomes were analyzed, and the findings of endoscopy, EUS and histology were compared. RESULTS The size measured by endoscopy was not significantly different from that measured by EUS and histology(r = 0.914 and r = 0.727 respectively). Accuracy for the depth of invasion was 92.5% with EUS. No patients showed invasion of the muscularis propria or metastasis to the regional lymph nodes. All rectal NETswere classified as grade 1 and demonstrated an L-cell phenotype. Mean follow-up duration was 407.54 ± 374.16 d. No patients had local or distant metastasis during the follow-up periods. CONCLUSION EUS is not essential for ER in the patient with small rectal NETs because of the prominent morphology and benign behavior.

Advantage of endoscopic mucosal resection with a cap for rectal neuroendocrine tumors

AIM: To compare the outcomes of endoscopic mucosal resection with a cap(EMR-C) with those of endoscopic submucosal dissection(ESD) for the resection of rectal neuroendocrine tumors.METHODS: One hundred and sixteen lesions in 114 patients with rectal neuroendocrine tumor(NET) resected with EMR-C or ESD were included in the study. This study was performed at Pusan National University Yangsan Hospital between July 2009 and August 2014. We analyzed endoscopic complete resection rate,pathologic complete resection rate,procedure time,and adverse events in the EMR-C(n = 65) and ESD(n = 51) groups. We also performed a subgroup analysis by tumor size.RESULTS: Mean tumor size was 4.62 ± 1.66 mm in the EMR-C group and 7.73 ± 3.14 mm in the ESD group(P < 0.001). Endoscopic complete resection rate was 100% in both groups. Histologic complete resection rate was significantly greater in the EMR-C group(92.3%) than in the ESD group(78.4%)(P = 0.042). Mean procedure time was significantly longer in the ESD group(14.43 ± 7.26 min) than in the EMR-C group(3.83 ± 1.17 min)(P < 0.001). Rates of histologic complete resection without complication were similar for tumor diameter ≤ 5 mm(EMR-C,96%; ESD,100%,P = 0.472) as well as in cases of 5 mm < tumor diameter ≤ 10 mm(EMR-C,80%; ESD,71.0%,P = 0.524).CONCLUSION: EMR-C may be simple,faster,and more effective than ESD in removing rectal NETs and may be preferable for resection of small rectal NETs.

Effect of angiotensin Ⅱ type 1 receptor blocker and angiotensin converting enzyme inhibitor on the intraocular growth factors and their receptors in streptozotocin-induced diabetic rats

AIM： To investigate the effect of angiotensin II type 1 receptor blocker （ARB） and angiotensin converting enzyme inhibitor （ACEI） on intraocular growth factors and their receptors in streptozotocin-induced diabetic rats. METHODS： Forty Sprague-Dawley rats were divided into 4 groups： control, diabetes mellitus （DM）, candesartan- treated DM, and enalapril-treated DM （each group, n---10）. After the induction of DM by streptozotocin, candesartan [ARB, 5 mg/（kg · d）] and enalapril [ACEI, 10 mg/（kg · d）] were administered to rats orally for 4Wko Vascular endothelial growth factor （VEGF） and angiotensin II （Ang II） concentrations in the vitreous were measured using enzyme-linked immunosorbent assays, and VEGF receptor 2 and angiotensin II type 1 receptor （ATIR） levels were assessed at week 4 by Western blotting. RESULTS： Vitreous Ang II levels were significantly higher in the DM group and candesartan-treated DM group than in the control （P=0.04 and 0.005, respectively）. Vitreous ATIR increased significantly in DM compared to the other three groups （P〈0.007）. Candesartan-treated DM rats showed higher vitreal ATIR concentration than the enalapril-treated DM group and control （P〈0.001 and P=0.005, respectively）. No difference in vitreous Ang II and ATIR concentration was found between the enalapril- treated DM group and control. VEGF and its receptor were below the minimum detection limit in all 4 groups. CONCLUSION： Increased Ang II and ATIR in the hyperglycemic state indicate activated the intraocular renin-angiotensin system, which is inhibited more effectively by systemic ACEI than systemic ARB.

Double layered self-expanding metal stents for malignant esophageal obstruction, especially across the gastroesophageal junction

AIM: To evaluate the clinical outcomes of double-layered self-expanding metal stents (SEMS) for treatment of malignant esophageal obstruction according to whether SEMS crosses the gastroesophageal junction (GEJ). METHODS: Forty eight patients who underwent the SEMS insertion for malignant esophageal obstruction were enrolled. Patients were classified as GEJ group (SEMS across GEJ, 18 patients) and non-GEJ group (SEMS above GEJ, 30 patients) according to SEMS position. Double layered (outer uncovered and inner covered stent) esophageal stents were placed. RESULTS: The SEMS insertion and the clinical improvement were achieved in all patients in both groups. Stent malfunction occurred in seven patients in the GEJ group and nine patients in the non-GEJ group. Tumor overgrowth occurred in five and eight patients, respectively, food impaction occurred in one patient in each group, and stent migration occurred in one and no patient, respectively. There were no significant differences between the two groups. Reflux esophagitis occurred more frequently in the GEJ group (eight vs five patients, P = 0.036) and was controlled by proton pump inhibitor. Aspiration pneumonia occurred in zero and five patients, respectively, and tracheoesophageal fistula occurred in zero and two patients, respectively. CONCLUSION: Double-layered SEMS are a feasible and effective treatment when placed across the GEJ for malignant esophageal obstruction. Double-layered SEMS provide acceptable complications, especially migration, although reflux esophagitis is more common in the GEJ group.

Endoscopic resection using band ligation for esophageal SMT in less than 10mm

AIM:To evaluate the safety and feasibility of endoscopic resection using band ligation(EMR-B) for the diagnostic and therapeutic removal of tumors located in the esophageal subepithelial region having originated from the submucosa.METHODS:From May 2009 to September 2014,after medical chart and endoscopic ultrasonography report review,a total of 15 esophageal tumors located in the submucosal layer were resected by EMR-B.Previous symptom,location,pathology,complete resection rate,incidence of complications,incidence of minor complication,size,length of procedures time and follow up months were evaluated.To evaluate local recurrence at the resection site,periodic follow-up endoscopic examination was undertaken in all of the patients.The first endoscopic examination was performed about 6 mo after the endoscopic resection.Thereafter,the endoscopic follow up were scheduled annually.RESULTS:The mean age was 50.3 ± 9.67 years.The mean tumor size was 6.93 ± 3.15 mm and most of the lesions size was between 5-10 mm in diameter(10/15,66.6%).In all patients,endoscopic en bloc resection was achieved.In one patient,the vertical margin was involved.The mean procedural time was 8.86 ± 3.66 min.In all patients,no evidence of severe complications such as perforation or bleeding occurred.Minor complications such as chest pain(2/15,13.3%) and heartburn(3/15,13.3%) were reported but they symptoms were controlled by proton pump inhibitors,ulcermin and/or analgesics.Histologic assessments of the removed specimens revealed 10 granular cell tumors(66.6%),4 leiomyomas(16.6%) and one lipoma(6.6%).No recurrence was observed during the mean follow up period of 45 ± 3.5 mo(range:5-64 mo).CONCLUSION:EMR-B might be considered safe and effective for the diagnosis and treatment of lesions measuring less than 10 mm in diameter.

Therapeutic efficacy and stent patency of transhepatic portal vein stenting after surgery

AIM To evaluate portal vein(PV) stenosis and stent patency after hepatobiliary and pancreatic surgery, using abdominal computed tomography(CT).METHODS Percutaneous portal venous stenting was attempted in 22 patients with significant PV stenosis(> 50%)-after hepatobiliary or pancreatic surgery- diagnosed by abdominal CT. Stents were placed in various stenotic lesions after percutaneous transhepatic portography. Pressure gradient across the stenotic segment was measured in 14 patients. Stents were placed when the pressure gradient across the stenotic segment was > 5 mm Hg or PV stenosis was > 50%, as observed on transhepatic portography. Patients underwent followup abdominal CT and technical and clinical success, complications, and stent patency were evaluated.RESULTS Stent placement was successful in 21 patients(technical success rate: 95.5%). Stents were positioned through the main PV and superior mesenteric vein(n = 13), main PV(n = 2), right and main PV(n = 1), left and main PV(n = 4), or main PV and splenic vein(n = 1). Patients showed no complications after stent placement. The time between procedure and final follow-up CT was 41-761 d(mean: 374.5 d). Twenty stents remained patent during the entire follow-up. Stent obstruction-caused by invasion of the PV stent by a recurrent tumor- was observed in 1 patient in a follow-up CT performed after 155 d after the procedure. The cumulative stent patency rate was 95.7%. Small in-stent low-density areas were found in 11(55%) patients; however, during successive follow-up CT, the extent of these areas had decreased.CONCLUSION Percutaneous transhepatic stent placement can be safe and effective in cases of PV stenosis after hepatobiliary and pancreatic surgery. Stents show excellent patency in follow-up abdominal CT, despite development of small in-stent low-density areas.

Comparison of cytotoxicity and wound healing effect of carboxymethylcellulose and hyaluronic acid on human corneal epithelial cells

AIM: To investigate the cytotoxic effect on human corneal epithelial cells(HCECs) and the ability to faciliate corneal epithelial wound healing of carboxymethylcellulose(CMC) and hyaluronic acid(HA).METHODS: HCECs were exposed to 0.5% CMC(Refresh plus, Allergan, Irvine, California, USA) and 0.1% and 0.3%HA(Kynex , Alcon, Seoul, Korea, and Hyalein mini,Santen, Osaka, Japan) for the period of 30 min, and 4, 12,and 24 h. Methyl thiazolyl tetrazoiun(MTT)-based calorimetric assay was performed to assess the metabolic activity of cellular proliferation and lactate dehydrogenase(LDH) leakage assay to assess the cytotoxicity. apoptotic response was evaluated with flow cytometric analysis and fluorescence staining with Annexin V and propiodium iodide. Cellular morphology was evaluated by inverted phase-contrast light microscopy and electron microscopy. The wound widths were measured 24 h after confluent HCECs were scratch wounded.RESULTS: The inhibitory effect of human corneal epithelial proliferation and cytotoxicity showed the time-dependent response but no significant effect. Apoptosis developed in flow cytometry and apoptotic cells weredemonstrated in fluorescent micrograph. The damaged HCECs were detached from the bottom of the dish and showed the well-developed vacuole formations. Both CMC and HA stimulated reepithehlialization of HCECs scratched, which were more observed in CMC.CONCLUSION: CMC and HA, used in artificial tear formulation, could be utilized without any significant toxic effect on HCECs. Both significantly stimulated HCEC reepithelialization of corneal wounds.

Surgical perspectives of symptomatic omphalomesenteric duct remnants: Differences between infancy and beyond

BACKGROUND The clinical manifestations of omphalomesenteric duct remnant(OMDR)can vary with the age at diagnosis,from asymptomatic incidental findings to symptoms related to gastrointestinal complications.The lifelong complication rates are reported as 4%-34%,and complications are more common in patients younger than 2 years of age.The authors attempted to identify different clinical features and management for the various pediatric age groups.AIM To find surgical perspectives for the pediatric age-related variants of OMDR and make recommendations for optimal management.METHODS The medical records of pediatric patients diagnosed with OMDR were reviewed retrospectively.Fifteen patients diagnosed based on incidental findings during other surgeries were excluded.The patients were divided into two groups based on age:<12 mo(infants)and>12 mo(beyond infancy).We analyzed the demographic characteristics,clinical manifestations,diagnostic tools,surgical procedures,and clinical outcomes of the patients and compared them for the age groups.Chi-squared and Fisher's exact tests were used for nominal scales and a Mann-Whitney test was used for ratio scales.RESULTS A total of 35 patients(7 infants,28 children beyond infancy)were finally included.In both groups,Meckel's diverticulum(MD)was the most common type of OMDR,while umbilical lesions were more common in the infant group(P=0.006).Hematochezia and abdominal pain were common in the beyond infancy group,while umbilical lesions were the most frequent symptoms in the infant group.Several diagnostic tools were used,but Meckel's scan was most useful in diagnosing OMDR in patients with painless rectal bleeding.Minimally invasive surgery was more commonly performed for children than for infants(P=0.016).Single-incision laparoscopic surgery(SILS)was performed for fifteen patients who underwent laparoscopic surgery.There were only three cases of postoperative complications,and all patients survived in good condition.CONCLUSION The clinical type of OMDR varies with age,umbilical lesions in infants,and MD beyond infancy.SILS is effective for managing children with MD regardless of age.

Congestive ischemic colitis successfully treated with antiinflammatory therapy: A case report

BACKGROUND Congestive ischemic colitis is a rare subtype of ischemic colitis with an unknown pathophysiology.Excluding conservative management,such as fasting,no established treatment exists;therefore,surgical intervention should be considered in some cases if symptoms worsen.Current literature suggests that anti-inflam-matory agents may effectively treat congestive ischemic colitis.CASE SUMMARY We present the case of a 68-year-old female patient who underwent laparoscopic left hemicolectomy for transverse colon cancer 3 years ago.Postoperatively,follow-up included an annual colonoscopy and abdominal computed tomography(CT)at a local clinic.However,progressive erythema and edema of the sigmoid colon were observed 1 year postoperatively.Upon admission to our hospital,she complained of abdominal pain and diarrhea.Abdominal CT showed thickening of the sigmoid colon walls,and colonoscopy revealed erythema,edema,and multiple ulcers with exudate in the sigmoid colon.CT angiography showed engorgement of the sigmoid vasa recta without any vascular abnormalities.The diagnosis was congestive ischemic colitis,and we treated the patient with anti-inflammatory agents.After 2 mo of glucocorticoid therapy(20 mg once daily)and 7 mo of 5-aminosalicylate therapy(1 g twice daily),the ulcers completely healed.She has not experienced any recurrence for 2 years.CONCLUSION Anti-inflammatory therapy,specifically glucocorticoids and 5-aminosalicylate,has demonstrated promising efficacy and introduces potential novel treatment options for congestive ischemic colitis.

New magnifying endoscopic classification for superficial esophageal squamous cell carcinoma

To assess the accuracy of a new magnifying endoscopy (ME) classification for predicting depth of invasion of superficial esophageal squamous cell carcinoma (SESCC). METHODSThis study included a total of 70 lesions in 69 patients with SESCC who underwent ME with narrow-band imaging (ME-NBI) before resection from August 2010 to July 2016. Accuracy of ME-NBI for predicting depth of invasion of SESCC was analyzed by using a new ME classification proposed by the Japan Esophageal Society (JES), and interobserver agreement was assessed. RESULTSOverall accuracy of ME-NBI for estimating depth of invasion of SESCC was 78.6%. Sensitivity and specificity of type B1 for tumors limited to the epithelial layer (m1) or invading into the lamina propria (m2) were 71.4% and 100%, respectively. Sensitivity and specificity of type B2 for tumors invading into the muscularis mucosa (m3) or superficial submucosa (≤ 200 μm, sm1) were 94.4% and 73.1%, respectively, while those of type B3 for tumors invading into the deep submucosa (> 200 μm, sm2) were 75.0% and 97.8%, respectively. Interobserver agreement was excellent (κ = 0.86, 95%CI: 0.76-0.95). CONCLUSIONThe recently developed JES ME classification is useful for predicting depth of invasion of SESCC, with reliable interobserver agreement.

Artificial intelligence based real-time microcirculation analysis system for laparoscopic colorectal surgery

BACKGROUND Colonic perfusion status can be assessed easily by indocyanine green(ICG)angiography to predict ischemia related anastomotic complications during laparoscopic colorectal surgery.Recently,various parameter-based perfusion analysis have been studied for quantitative evaluation,but the analysis results differ depending on the use of quantitative parameters due to differences in vascular anatomical structure.Therefore,it can help improve the accuracy and consistency by artificial intelligence(AI)based real-time analysis microperfusion(AIRAM).AIM To evaluate the feasibility of AIRAM to predict the risk of anastomotic complication in the patient with laparoscopic colorectal cancer surgery.METHODS The ICG curve was extracted from the region of interest(ROI)set in the ICG fluorescence video of the laparoscopic colorectal surgery.Pre-processing was performed to reduce AI performance degradation caused by external environment such as background,light source reflection,and camera shaking using MATLAB 2019 on an I7-8700k Intel central processing unit(CPU)PC.AI learning and evaluation were performed by dividing into a training patient group(n=50)and a test patient group(n=15).Training ICG curve data sets were classified and machine learned into 25 ICG curve patterns using a self-organizing map(SOM)network.The predictive reliability of anastomotic complications in a trained SOM network is verified using test set.RESULTS AI-based risk and the conventional quantitative parameters including T1/2max,time ratio(TR),and rising slope(RS)were consistent when colonic perfusion was favorable as steep increasing ICG curve pattern.When the ICG graph pattern showed stepped rise,the accuracy of conventional quantitative parameters decreased,but the AI-based classification maintained accuracy consistently.The receiver operating characteristic curves for conventional parameters and AI-based classification were comparable for predicting the anastomotic complication risks.Statistical performance verifications were improved in the AI-based analysis.AI analysis was evaluated as the most accurate parameter to predict the risk of anastomotic complications.The F1 score of the AI-based method increased by 31% for T1/2max,8% for TR,and 8% for RS.The processing time of AIRAM was measured as 48.03 s,which was suitable for real-time processing.CONCLUSION In conclusion,AI-based real-time microcirculation analysis had more accurate and consistent performance than the conventional parameter-based method.

Assessment of disease activity by fecal immunochemical test in ulcerative colitis

AIM To evaluate the efficacy of quantitative fecal immunochemical test(FIT) as biomarker of disease activity in ulcerative colitis(UC).METHODS Between February 2013 and November 2014, a total of 82 FIT results, obtained in conjunction with colonoscopies, were retrospectivelyevaluated for 63 patients with UC. The efficacy of FIT for evaluation of disease activity was compared to colonoscopic findings. Quantitative fecal blood with automated equipment examined from collected feces. Endoscopic disease severity were assessed using the Mayo endoscopic subscore(MES) classification. The extent of disease were classified by proctitis(E1), left sided colitis(E2), and extensive colitis(E3). Clinical activity were subgrouped by remission or active.RESULTS All of 21 patients with MES 0 had negative FIT(< 7 ng/mL), but 22 patients with MES 2 or 3 had a mean FIT of > 134.89 ng/m L. The sensitivity, specificity, positive predictive value(PPV), negative predictive value(NPV) and accuracy of negative FIT about mucosal healing were 73.33%, 81.82%, 91.49%, 51.43% and 73.17%, respectively. The sensitivity, specificity, PPV, NPV and accuracy of predictive value of positive FIT(cutoff value > 100 ng/mL) about active disease status were 45.45%, 93.33%, 71.43%, 82.35%and 26.83%, respectively. Among patients with clinical remission, FIT was negative in 31(81.6%) of 38 cases, with a mean fecal hemoglobin concentration of 6.12 ng/mL(range, negative to 80.9 ng/mL) for this group of patients. Among patients with clinical active disease, FIT was negative in 16(36.4%) out of 44 cases, with a mean fecal hemoglobin concentration > 167.4 ng/mL for this group of patients. FIT was positively correlated with endoscopic activity(r = 0.626, P < 0.01) and clinical activity(r = 0.496, P < 0.01). But, FIT did not correlate with the extent of disease(r =-0.047, P = 0.676)CONCLUSION Quantitative FIT can be a non-invasive and effective biomarker for evaluation of clinical and endoscopic activity in UC, but not predict the extent of disease.

Rectal tonsil:A case report and literature review

The rectal tonsil,a reactive proliferation of lymphoidtissue located in the rectum,is rare.Histologically,benign lymphoid hyperplasia of the rectum is usuallycharacterized by large lymphoid follicles with activegerminal centers and a narrow surrounding mantlezone and marginal zone.This lesion is benign,but must be differentiated from the polypoid type of mucosaassociated lymphoid tissue lymphomas.In the current paper,we present a case of rectal tonsil in a 59-yearold woman.We describe the endoscopic ultrasound imaging findings with literature review.

Second-look endoscopy and factors associated with delayedbleeding after endoscopic submucosal dissection

Endoscopic submucosal dissection(ESD) is a widely used procedure as curative treatment for superficial gastric neoplasms, including early gastric cancer without lymph node metastasis. However, ESD requires advanced endoscopic skill and there is a major concern regarding complications from bleeding. So far, extensive efforts have been made to develop strategies to reduce post-ESD bleeding. Use of proton pump inhibitors and coagulating exposed vessels on the ulcer floor after ESD are strategies known to reduce the risk of delayed bleeding. Second-look endoscopy(SLE) is also carried out to reduce delayed bleeding following ESD in many institutions. However, the incidence of bleeding still remains around 5%, and further measures are needed to reduce delayed bleeding after gastric ESD. Recently, three randomized studies indicated that routine SLE was unnecessary. Although routine SLE may not be recommended for all patients after gastric ESD, SLE might be an important tool for the prevention of the delayed bleeding in selected high-risk patients. Thus, the identification of the risk factors, such as large size of resected specimen and treatment with multiple antiplatelet medications, may help to further guide clinicians in deciding whether to perform SLE. Studies carried out on larger cohorts are necessary to clarify the efficacy of SLE after ESD in the prevention of post-ESD bleeding in potentially high-risk patients.