Systematic review and Meta-analysis of treating open angle glaucoma with gonioscopy-assisted transluminal trabeculotomy

●AIM:To systematically review and Meta-analyze studies of managing open angle glaucoma(OAG)with gonioscopyassisted transluminal trabeculotomy(GATT)and to evaluate its effectiveness and safety.●METHODS:Eligible studies were retrieved and screened from five main electronic databases.Mean difference(MD)was hired to show the pooled effectiveness of intraocular pressure(IOP)and medication decrease achieved by GATT.In addition,combined surgical success and reoperation rates were calculated,and complications were also summarized.●RESULTS:Ten studies were included for systematic review,but one study was not pooled for Meta-analysis due to the repeated data.The combined IOP decrease after GATT was 9.81 mm Hg(95%CI:7.98-11.63 mm Hg)which showed significant reduction from the baselines(Z=10.52,P<0.0001).Similarly,the number of medications after GATT also decreased distinctly compared with that of medication before the surgery(Z=9.09,P<0.0001),and the pooled medication decrease was 1.68(95%CI:1.31-2.04).In addition,the combined surgical success rate was 85%,while the pooled reoperation rate was 20%.Sightthreatening complications occurred scarcely,whereas the pooled occurrence rate of hyphemia was as high as 36.0%.●CONCLUSION:GATT could effectively lower IOP and decrease medications for patients with OAG.Moreover,the procedure appears to be a safe and promising treatment for OAG due to its minimally-invasive and conjunctiva-sparing nature.

Calculation mode of side friction for large open caisson

To overcome the problems in design methodologies and construction control measures for the large open caisson, systematic research was conducted on the side friction calculation mode of the large open caisson. Based on the field monitoring data of lateral soil pressure on the side wall of the open caisson for the southern anchorage of the Maanshan Yangtze River Highway Bridge, the statistical result of the side friction under different buried depths of the cutting edge of the open caisson was back-analyzed; and the side friction distribution of the large open caisson was underlined. The analysis results indicate that when the buried depth of the cutting edge is smaller than a certain depth H0, the side friction linearly increases with the increase in the buffed depth. However, as the buffed depth of the cutting edge is larger than H0, the side friction shows a distribution with small at both ends and large in the middle. The top of the distribution can be regarded as a linear curve, while the bottom as a hyperbolic curve. As the buffed depth of cutting edge increases continuously, the peak value of the side friction linearly increases and the location of the peak value gradually moves down. Based on the aforementioned conclusions, a revised calculation mode of the large open caisson is presented. Then, the calculated results are compared with the field monitoring data, which verifies the feasibility of the proposed revised calculation mode.

New strategy during complicated open appendectomy: Convert open operation to laparoscopy

AIM: To introduce a new strategy during complicated open appendectomy - converting open operation to laparoscopy.

Influence of bed elevation discordance on flow patterns and head losses in an open-channel confluence

Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is common.Studies of schematized confluences with a step at the interface between the tributary and the main channel bed reveal that bed elevation discordance is an important additional control for the confluence hydrodynamics.This study aimed to improve understanding of the influence of bed elevation discordance on the flow patterns and head losses in a right-angled confluence of an open channel with rectangular cross-sections.A large eddy simulation (LES)-based numerical model was set up and validated with experiments by others.Four configurations with different bed discordance ratios were investigated.The results confirm that, with increasing bed elevation discordance, the tributary streamlines at the confluence interface deviate less from the geometrical confluence angle, the extent of the recirculation zone (RZ) gets smaller, the ratio of the water depth upstream to that downstream of the confluence decreases, and the water level depression reduces.The bed elevation discordance also leads to the development of a large-scale structure in the lee of the step.Despite the appearance of the large-scale structure, the reduced extent of the RZ and associated changes in flow deflection/contraction reduce total head losses experienced by the main channel with an increase of the bed discordance ratio.It turns out that bed elevation discordance converts the lateral momentum from the tributary to streamwise momentum in the main channel more efficiently.

STRESS CONCENTRATIONS IN CYLINDRICAL SHELLS WITH LARGE OPENINGS

Based on Donnell's shallow shell equation, a new method is given in this paper to analyze theoretical solutions of stress concentrations about cylindrical shells with large openings. With the method of complex variable function, a series' of conformal mapping functions are obtained from different cutouts' boundary curves in the developed plane of a cylindrical shell to the unit circle. And, the general expressions for the equations of a cylindrical shell, including the solutions of stress concentrations meeting the boundary conditions of the large openings' edges, are given in the mapping plane. Furthermore, by applying the orthogonal function expansion technique, the problem can be summarized into the solution of infinite algebraic equation series. Finally, numerical results are obtained for stress concentration factors at the cutout's edge with various opening's ratios and different loading conditions. This new method, at the same time, gives a possibility to the research of cylindrical shells with large non-circular openings or with nozzles.

Oval mucosal opening bloc biopsy after incision and widening by ring thread traction for submucosal tumor

Gastric submucosal tumors(SMTs) less than 2 cm are generally considered benign neoplasms, and endoscopic observation is recommended, but SMTs over 2 cm, 40% of which are gastrointestinal stromal tumors(GISTs), have malignant potential. Although the Japanese Guidelines for GIST recommend partial surgical resection for GIST over 2 cm with malignant potential as well as en bloc large tissue sample to obtain appropriate and large specimens of SMTs, several reports have been published on tissue sampling of SMTs, such as with endoscopic ultrasound sound fine needle aspiration, submucosal tunneling bloc biopsy, and the combination of bite biopsy and endoscopic mucosal resection. Because a simpler, more accurate method is needed for appropriate treatment, we developed oval mucosal opening bloc biopsy after incision and widening by ring thread traction for submucosal tumor(OMOB) approach. OMOB was simple and enabled us to obtain large samples under direct procedure view as well as allowed us to restore to original mucosa.

Impact of depth ratio on flow structure and turbulence characteristics of compound open channel flows

Compound open channel flows appear in most natural rivers are of great importance in river management and flood control.In this study,large eddy simulations were carried out to simulate the compound open channel flows with four different depth ratios(hr=0.10,0.25,0.50,and 0.75).The main flow velocity,secondary flow,Reynolds stress,and bed shear stress were obtained from numerical simulations.The depth-averaged stream wise momentum equation was used to quantify the lateral momentum exchange between the main channel and floodplain.The instantaneous coherent structures were presented by the Q criterion method.The impact of hr on flow structure and turbulence charac-teristics was analyzed.The results showed that with the increase of hr,the high velocity area in the main channel shifted to the floodplain,and the dip phenomenon became more obvious;the Reynolds stress largely contributed to the lateral momentum exchange within the flows near the side walls of floodplain;and the vortex structures were found to significantly increase in the floodplain region.

Back to basics:A meta-analysis of stump management during open appendicectomy for uncomplicated acute appendicitis

AIM: To compare simple ligation vs stump invagination during open appendicectomy for uncomplicated acute appendicitis on the risk of postoperative complications. METHODS: A meta-analysis was conducted on randomised controlled trials comparing the two stump closure methods in open appendicectomy. Databases searched were Pub Med, EMBASE and Cochrane Library databases. Included were those studies focusing on inflamed and suppurative appendicitis while perforated and gangrenous appendix was excluded. We also excluded retrospective case-control studies, commentaries, historical technical articles, or trials involving laparoscopic appendicectomies. The outcome of the meta-analysis was to find eventual differences in theincidence of postoperative ileus and wound infections between the two techniques of stump invagination. RESULTS: Seven studies were included corresponding to 1468 patients. Postoperative complications consisted in wound infections(7%), ileus(4%), pyrexia(2%), vomiting(1%), obstructions from adhesions(0.1%). No cases of peritonitis, fecal fistulas(stump leaks), abdominal abscesses or wound dehiscences were reported. Postoperative ileus within the first 72 h was four times more frequent with stump invagination compared to simple ligation(OR: 4.06; 95%CI: 2.14-7.70; P < 0.0001). No significant differences were noted for wound infections(OR: 1.24; 95%CI: 0.83-1.87; P = 0.30) while for the remaining complications the incidence was extremely low in both groups. There was a high homogeneity on results(Q value for heterogeneity of postoperative ileus P = 0.17; Q value for heterogeneity of wound infections P = 0.98). CONCLUSION: Stump invagination does not seem to prevent infective complications but is associated with an increased risk of postoperative ileus in uncomplicated cases. Appropriate studies on complicated appendicitis should now evaluate the influence of the two techniques in this higher-risk subgroup.

Impact of open hepatectomy on postoperative bile leakage in patients with biliary tract cancer

BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer.AIM To evaluate the incidence,risk factors,and management of bile leakage after open hepatectomy in patients with biliary tract cancer.METHODS We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February 2023.Bile leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on imaging.The incidence,severity,timing,location,and treatment of the bile leaks were recorded.The risk factors for bile leakage were analyzed using univariate and multivariate logistic regression analyses.RESULTS The incidence of bile leak was 16.7%(20/120),and most cases were grade A(75%,15/20)according to the International Study Group of Liver Surgery classification.The median time of onset was 5 d(range,1-14 d),and the median duration was 7 d(range,2-28 d).The most common location of bile leakage was the cut surface of the liver(70%,14/20),followed by the anastomosis site(25%,5/20)and the cystic duct stump(5%,1/20).Most bile leaks were treated conservatively with drainage,antibiotics,and nutritional support(85%,17/20),whereas some required endoscopic retrograde cholangiopancreatography with stenting(10%,2/20)or percutaneous transhepatic cholangiography with drainage(5%,1/20).Risk factors for bile leakage include male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion.CONCLUSION Bile leakage is a frequent complication of open hepatectomy for biliary tract cancer.However,most cases are mild and can be conservatively managed.Male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion were associated with an increased risk of bile leak.

Open education is a really complicated idea

There are some very good things about open education.This way of teaching allows the students to grow as people,and to develop their own interests in many subjects.Open education allows students to be responsible for their own education,as they are responsible for what they do in life.Some students do badly

AN APPLICATION OF THEORETICAL SOLUTIONS ABOUT CYLINDRICAL SHELLS WITH SMALL OPENINGS

Stress concentrations about thin cylindrical shells with small openings are reconsidered front a nerv angle. There is a sort of special internal relation between theoretical solutions about cylindrical shells,vith large openings and one,with small openings. Using this relation, the extent of applying the theory about small openings to engineering practice is estimated again, thus an idea of how to use this theory and a nerv appraisal of the application of theoretical solutions about cylindrical shells with small openings to engineering practice are given.

Meta-analysis of laparoscopic vs open cholecystectomy in elderly patients

AIM:To investigate the comparative effect of laparoscopic and open cholecystectomy in elderly patients.METHODS:Laparoscopic cholecystectomy has induced a revolution in the treatment of gallbladder disease.Nevertheless,surgeons have been reluctant to implement the concepts of minimally invasive surgery in older patients.A systematic review of Medline was embarked on,up to June 2013.Studies which provided outcome data on patients aged 65 years or older,subjected to laparoscopic or open cholecystectomy were considered.Mortality,morbidity,cardiac and pulmonary complications were the outcome measures of treatment effect.The methodological quality of selected studies was appraised using valid assessment tools.Τhe random-effects model was applied to synthesize outcome data.RESULTS:Out of a total of 337 records,thirteen articles(2 randomized and 11 observational studies)reporting on the outcome of 101559 patients(48195in the laparoscopic and 53364 in the open treatment group,respectively)were identified.Odds ratios(OR)were constantly in favor of laparoscopic surgery,in terms of mortality(1.0%vs 4.4%,OR=0.24,95%CI:0.17-0.35,P<0.00001),morbidity(11.5%vs 21.3%,OR=0.44,95%CI:0.33-0.59,P<0.00001),cardiac(0.6%vs 1.2%,OR=0.55,95%CI:0.38-0.80,P=0.002)and respiratory complications(2.8%vs 5.0%,OR=0.55,95%CI:0.51-0.60,P<0.00001).Critical analysis of solid study data,demonstrated a trend towards improved outcomes for the laparoscopic concept,when adjusted for age and co-morbid diseases.CONCLUSION:Further high-quality evidence is necessary to draw definite conclusions,although bestavailable evidence supports the selective use of laparoscopy in this patient population.

Two-year outcomes of ab interno trabeculectomy with the Trabectome for Chinese primary open angle glaucoma： a retrospective multicenter study

AIM： To evaluate the 2-year efficacy and safety of ab interno trabeculectomy with the Trabectome in Chinese primary open angle glaucoma （POAG） patients. METHODS： This was a multicenter, retrospective, observational study and included POAG patients with or without visually-significant cataracts. The Chinese patients were enrolled from three glaucoma centers and a group of comparable Japanese POAG patients was analyzed from our international Trabectome database. The patients received Trabectome or a combined surgery with phacoemulsification and intraocular lens implantation. The primary outcome was intraocular pressure （IOP） reduction. Secondary outcomes included reduction of glaucoma medications, surgical complications, and success at 2y. Success was defined as： 1） IOP≤21 mm Hg and at least 20% IOP reduction from baseline after 3mo at any two consecutive visits; 2） no additional glaucoma surgery required. RESULTS： A total of 42 Chinese POAG patients from three glaucoma centers were enrolled. Twelve patients underwent Trabectome surgery combined with phacoemulsification and intraocular lens implantation while the remainder underwent Trabectome surgery alone. Thirteen patients had a history of failed glaucoma surgery and were considered as complicated cases. In China data, the mean preoperative IOP was 21.4±1.23 mm Hg. The Trabectome lowered IOP to 17.9±1.8 mm Hg at 2y （P=0.05）. The number of glaucoma medications also decreased significantly from a baseline of 2.0±0.9 to 1.1±0.8 at 2y post-surgery （P=0.04）. The overall 2-year success rate was 78%, with patients undergoing combined surgery having a higher success rate compared with those undergoing Trabectome surgery alone （100% vs 76%）. In Japan data, the mean preoperative IOP was 20.8±7.7 mm Hg. The Trabectome lowered IOP to 12.20±2.0 mm Hg at 2y. The number of glaucoma medications also decreased significantly from a baseline of 2.1±0.9 to 3.4±0.6 at 2y post-surgery. In all patients, no major complications were seen. CONCLUSION： Surgery with the Trabectome appears to be an efficient and safe procedure in Chinese POAG patients in the long-term.

Long-term complications of the transmeatal approach (Open Transcanal) in cochlear implants: A follow-up study

Objective: Multiple alternative approaches of cochlear implant surgery have been described, such as the suprameatal approach, transcanal approach, transmeatal approach and middle cranial fossa approach.Transmeatal(open trnascanal) approach has not been adapted since first described in the clinical field.we aimed to assess the long-term complications of the transmeatal approach in a series of 131 patients at our center between 2004 and 2008.Methods: This study was a retrospective case series of all patients who underwent cochlear implants with the transmeatal(open transcanal) approach from May 2004 to December 2008 at King Faisal Specialist and Research Hospital(Riyadh, Saudi Arabia), which were conducted by the same surgeon.Results: Complications were observed often with various combinations-recurrent otitis externa, posterior tympanic membrane perforation, electrode extrusion, cholesteatoma, and chronic mastoiditis. The overall long-term complication rate was 16%(21/131). The gap between the implantation and the diagnosis of a complication ranged from <1 year to 11 years. Major complications were as follows:cholesteatoma in 5(3.8%) patients, extrusion of the electrode in 5(3.8%) patients, and tympanic membrane perforation or deep retractions in 5(3.8%) patients. Minor complications were as follows: recurrent mastoiditis with/without concomitant temporary facial nerve palsy in 4(3%) patients, recurrent otitis externa infections in 7(5%) patients, and weakness of the posterior canal wall in 1 patient.Conclusion: The transmeatal approach posed an high rate of complications on long-term follow-up such as cholestetoma formation, extrusion of electrode or perielectrode reaction formation to tympanic membrane and external auditory canal.

Laparoscopic vs open donor nephrectomy:Lessons learnt from single academic center experience

AIM To compare laparoscopic and open living donor neph-rectomy, based on the results from a single center during a decade.METHODS This is a retrospective review of all living donor neph-rectomies performed at the Massachusetts General Hospital, Harvard Medical School, Boston, between 1/1998 - 12/2009. Overall there were 490 living donors, with 279 undergoing laparoscopic living donor nephrectomy （LLDN） and 211 undergoing open donor nephrectomy （OLDN）. Demographic data, operating room time, the effect of the learning curve, the number of conversions from laparoscopic to open surgery, donor preoperative glomerular fltration rate and creatinine （Cr）, donor and recipient postoperative Cr, delayed graft function and donor complications were analyzed. Statistical analysis was performed.RESULTSOverall there was no statistically significant differencebetween the LLDN and the OLDN groups regardingoperating time, donor preoperative renal function, donorand recipient postoperative kidney function, delayed graftfunction or the incidence of major complications. Whenthe last 100 laparoscopic cases were analyzed, there wasa statistically significant difference regarding operatingtime in favor of the LLDN, pointing out the importanceof the learning curve. Furthermore, another significantdifference between the two groups was the decreasedlength of stay for the LLDN （2.87 d for LLDN vs 3.6 d for OLDN）.CONCLUSION Recognizing the importance of the learning curve, this paper provides evidence that LLDN has a safety profle comparable to OLDN and decreased length of stay for the donor.

Experience with Open Prostatectomy in Lomé, Togo

Background: Open prostatectomy is the most commonly available surgical procedure for benign prostatic hyperplasia and this is the case in most countries in West African even with all the limitations of the procedure. Objective: The objective is to determine the pattern and outcomes of open prostatectomy in Lomé. Patients & Methods: From December 2011 to November 2012, we conducted a descriptive cross-sectional study on a series of patients treated for prostate adenoma. Dysuria was assessed using the International Prostate Symptom Score (IPSS). The history of each patient was recorded, as well as paraclinical data. All patients were surgically treated via abdominal incision procedure. The data obtained included the patients’ demographics, clinical features, the IPSS scores, investigations, type of open prostatectomy, outcome and follow-up. The data were analyzed for means and frequencies using Epi Info version 3.5.3. Results: Fifty-four consecutive patients underwent surgery consecutively, their ages ranging from 40 to 92 years, with an average of 67.27 ± 12.50 years. In all, 46 (85.2%) patients presented with obstructive symptoms and 26 (48.1%) presented with urinary retention. The average prostate volume was 114.31 ± 20.11 cm3 with a range of 31 - 485 cm3. The average blood loss at surgery was 425.92 ± 38.2 ml with an average operating time of 66.05 ± 15.75 mins and the main complications were hemorrhaging and clot retention in 7 (13%), epididymo-orchitis in 9 (16.7%), and urinary incontinence in 6 (11.1%) patients. IPSS scores were under 7 in 92% of patients three months after surgery and the mortality rate was 3.7%. Conclusion: This study has shown that open prostatectomy in our environment is still the commonest surgical option for benign prostatic hyperplasia with good outcomes though with manageable complications.

Search for production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at√s=8 TeV using CMS open data

In this study,we conducted a search for dark matter using a part of the data recorded by the CMS experiment during run-I of the LHC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−1.These data were gathered from the CMS open data.Dark matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum channel.One benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CMS open data.No evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

A Method of Reliability Allocation of a Complicated Large System

Aiming at the problem of reliability allocation for a complicated largesystem, a new thought is brought up. Reliability allocation should be a kind of decision-makingbehavior; therefore the more information is used when apportioning a reliability index, the morereasonable an allocation is obtained. Reliability allocation for a complicated large system consistsof two processes, the first one is a reliability information reporting process from bottom to top,and the other one is a reliability index apportioning process from top to bottom. By a typicalexample, we illustrate the concrete process of reliability allocation algorithms.

Safety of fast-track rehabilitation after gastrointestinal surgery:Systematic review and meta-analysis

AIM: To compare the safety of fast-track rehabilitation protocols (FT) and conventional care strategies (CC), or FT and laparoscopic surgery (LFT) and FT and open surgery (OFT) after gastrointestinal surgery.

LARGE EDDY SIMULATION OF PULSATING TURBULENT OPEN CHANNEL FLOW

Pulsating turbulent open channel flow has been investigated by the use ofLarge Eddy Simulation (LES) tech-nique coupled with dynamic Sub-Grid-Scale (SGS) model for turbulentSGS stress to closure the governing equations. Three-dimensional filtered Navier-Stokes equationsare numerically solved by a fractional — step method. The objective of this study is to deal withthe behavior of the pulsating turbulent open channel flow and to examine the reliability of the LESapproach for predicting the pulsating turbulent flow. In this study, the Reynolds number (Re_τ) ischosen as 180 based on the friction velocity and the channel depth. The frequency of the drivingpressure gradient for the pulsating turbulent flow ranges low, medium and high value. Statisticalturbulence quantities as well as the flow structures are analyzed.