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Patient selection for pediatric extracorporeal membrane oxygenation (ECMO) support has broadened over the years to include children with pre-existing neurologic morbidities. We aimed to determine the prevalence and nature of pre-ECMO neurologic disorders or disability and investigate the association between pre-ECMO neurologic disorders or disability and mortality and unfavorable neurologic outcome.Multicenter retrospective observational cohort study.Eight hospitals reporting to the Pediatric ECMO Outcomes Registry between October 2011 and June 2019.Children younger than 18 years supported with venoarterial or venovenous ECMO.The primary exposure was presence of pre-ECMO neurologic disorders or moderate-to-severe disability, defined as Pediatric Cerebral Performance Category (PCPC) or Pediatric Overall Performance Category (POPC) 3-5. The primary outcome was unfavorable outcome at hospital discharge, defined as in-hospital mortality or survival with moderate-to-severe disability (discharge PCPC 3-5 with deterioration from baseline).Of 598 children included in the final cohort, 68 of 598 (11%) had a pre-ECMO neurologic disorder, 70 of 595 (12%) had a baseline PCPC 3-5, and 189 of 592 (32%) had a baseline POPC 3-5. The primary outcome of in-hospital mortality ( n = 267) or survival with PCPC 3-5 with deterioration from baseline ( n = 39) was observed in 306 of 598 (51%). Overall, one or more pre-ECMO neurologic disorders or disability were present in 226 of 598 children (38%) but, after adjustment for age, sex, diagnostic category, pre-ECMO cardiac arrest, and ECMO mode, were not independently associated with increased odds of unfavorable outcome (unadjusted odds ratio [OR], 1.34; 95% CI, 1.07-1.69; multivariable adjusted OR, 1.30; 95% CI, 0.92-1.82).In this exploratory study using a multicenter pediatric ECMO registry, more than one third of children requiring ECMO support had pre-ECMO neurologic disorders or disability. However, pre-existing morbidities were not independently associated with mortality or unfavorable neurologic outcomes at hospital discharge after adjustment for diagnostic category and other covariates.

This study aimed to determine the cost-effectiveness of drug-coated balloon (DCB) angioplasty compared with conventional balloon angioplasty (cPTA) in patients with arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs) dysfunction from a Singapore healthcare perspective.Existing cost-effectiveness studies comparing DCB and cPTA have not incorporated AVF/AVG abandonment costs. This Markov model-based economic evaluation incorporated AVF/AVG creation and maturation costs on top of routine intervention costs to model a hypothetical cohort of 60-year-old AVF/AVG flow dysfunction patients. Effectiveness was measured in quality-adjusted life-years. Cost-effectiveness was assessed using incremental net monetary benefit (NMB) at a Singapore willingness-to-pay threshold of Singapore dollar (S$)87 000. Deterministic and probabilistic sensitivity analyses were performed to examine parameter uncertainty. To test hypotheses regarding cost-effectiveness, intervention counts per patient, cumulative incidence functions of AVF/AVG abandonment, and survival curves of death were compared between DCB and cPTA.DCB was not cost-effective at 3-year horizon (NMB = -S$1424), but was cost-effective at 1- and 6-year horizons (NMB = S$356 and S$3738, respectively). At 3 years, there was a 34.5% probability of DCB being cost-effective, but at 1- and 6-year horizons there was, respectively, 58.6% and 59.9% probability of DCB being cost-effective. DCB had graphically less AVF/AVG-abandonments, but this was not statistically significant (P = .21). Differences in other parameters were neither graphically nor statistically significant.With AVF/AVG abandonment considered, DCB may be weakly cost-effective compared with cPTA in treating AVF/AVG flow dysfunction. AV access creation and maturation costs could have important explanatory value in assessing DCB cost-effectiveness.

Atypical or complex clubfoot constitutes a small number of cases. Due to the difference in complexity of anatomy, standard deformity correction by Ponseti is not effective. Hence a modified Ponseti method was advised which focuses on deformity differences for treatment. We conducted a prospective study to analyze the outcome in atypical or complex clubfoot treated with the modified Ponseti method. All the children of age less than 1 year were included in the study with atypical or complex clubfoot. Every case was treated according to the modified Ponseti method and tenotomy. Pirani scores were measured at pretreatment, each visit, before application of a brace, and at the latest follow-up. Statistical analysis of all continuous and categorical variables was done. A total of 30 patients (47 feet) were included in the study. Mean Pirani score improved from 5.69 at presentation to 0.45 at time of brace application and latest follow-up 0.34 (p.001). Six patients (9 feet) had a relapse which was managed with recasting. The mean Pirani score of relapse was 0.72, which after correction reduced to 0.11 (p = .008). Six patients had cast-related complications which were managed with conservative treatment. With an increase in popularity of the Ponseti method, a greater number of complex clubfoot cases are seen due to inadequate reduction or slippage of cast or improper cast application techniques. All these need to be identified at an early age. This helps in proper treatment and improves the quality of life as well as foot appearance.

Mycetoma is a neglected tropical infectious disease which runs a prolonged and protracted course. Microbiological confirmation is diagnostic yet unreliable due to poor sensitivity and variable availability of culture facilities in resource poor settings.A retrospective review was performed on electronic records (histopathology, microbiology, and radiology) of all patients who underwent skin biopsies with mycetoma as one of the clinical differential diagnoses from year 2016 to 2020.Out of 73 patients biopsied with a differential of mycetoma, 42 fit the clinical triad of swelling-sinuses-granules. After clinical, microbiological, pathological, and radiological correlation, 31 cases were of eumycetoma and seven were of actinomycetoma. Mean patient age was 37.58 ± 13.8 years with a male to female ratio 2.45 : 1 and mean disease duration of 11.31 ± 10.9 years. Histopathological findings revealed fungal hyphae in 18 cases and gram-positive bacteria in six cases. Fungal culture was positive in 13 cases with the three commonest organisms being Madurella mycetomatis in five cases, Fusarium and Aspergillus nidulans in two cases each. X-ray changes of soft tissue, bones, and joints were seen in 25 cases, and "dot-in-circle" sign was seen in eight of nine MRIs.Eumycetoma was more common than actinomycetoma in our setup, ratio being 4.43 : 1. A clinical triad of swelling, multiple sinuses and grainy discharge with any one diagnostic support (histopathology/radiology) is sufficient to make a definitive diagnosis of mycetoma in the absence of microbiological identification.

Introduction- Monteggia is a fracture of the proximal third of the ulna with dislocation of the radial head from both the proximal radioulnar and radio-capitellar joints. At present in most case scenario all the monteggia fractures in adults operated with ORIF platting but hereby we have study about monteggia fracture managed with CRIF with rush nail compared with ORIF and platting. This study aimed to see the clinical and functional outcome of m Aim- onteggia fracture xation with Rush nail compared to platting in adult. A prospective study was conducted over 6 months of a total of 30 patients Material and Method- with monteggia fracture operated with rush nail and 30 patient operated with platting. Patients were divided by randomized controlled trial. All these 60 patients were followed up for mean duration of 6 months. The postoperative Mayo Elbow Performance Index at the tim Results- e of follow-up ranged from 65 to 100, with twenty-two excellent, ve good, three fair, and no poor results in operated case with rush nail and twenty-three excellent, four good, three fair, no poor result in operated case with platting. The radial head remained in a completely reduced position in twenty-ve patient (86%) and was subluxated in ve patients (14%) in operated case with rush nail and radial head completely reduced position in twenty-eight patient (94%) and was subluxated in two patient (6%) in operated case with platting at the time of the latest follow-up. Radiographically, there were twenty-six good, four fair, and no poor results operated with rush nail. A good radiographic result was obtained in all of the patients who had undergone open reduction and platting within three years after the injury. In overall comparison of Conclusion- clinical, functional and radiological outcome it was found that Rush nail gives superior results than platting.

Drug-coated balloon angioplasty (DCBA) has been studied as a potentially superior option compared to conventional percutaneous transluminal angioplasty (PTA) in treating below-the-knee (BTK) arteries in chronic limb-threatening ischemia (CLTI). The aim of this study is to examine the cost-effectiveness of DCBA versus PTA in BTK arteries based on a randomized controlled trial.A prospective economic study was embedded in a randomized controlled trial of 138 patients with CLTI. Resource use and health outcomes were assessed at baseline, and at 3, 6 and 12 months post-intervention. Costs were calculated from a societal perspective and health outcomes measured using quality-adjusted life years with probabilistic sensitivity analysis performed to account for subject heterogeneity.Compared with participants randomized to receive PTA, participants randomized to DCBA gained an average baseline-adjusted quality-adjusted life years (QALYs) of .012 while average total costs were USD$1854 higher; this translates to an incremental cost-effectiveness ratio (ICER) of US$154,500 additional cost per QALY gained. However, the estimate of ICER had substantial variance with only 48% of bootstrap ICERs meeting a benchmark threshold of US$57,705 (the average gross domestic product (GDP) per capita of Singapore).The use of DCBA in BTK arteries in CLTI patients was not cost-effective compared with PTA.2, Randomized trial.

To study the safety and efficacy of cutting balloon angioplasty (CBA) followed by paclitaxel drug-coated balloon (PCB) angioplasty for recurrent venous lesions in arteriovenous fistulas (AVFs).We conducted a prospective single-arm cohort study of CBA followed by PCB angioplasty for recurrent AVF stenoses between September 2017 and April 2019. In total, 44 participants were recruited. Target lesions were included if they had recurred within 12 months post-angioplasty, were = 0.5 cm upstream from the arteriovenous anastomosis, and did not involve the central veins. Up to two non-target lesions per circuit/participant with the same definition were allowed. Lesions were considered separate when there was an intervening 2-cm segment of normal vessel. Technical success was defined as complete lesion effacement on angioplasty. End-points of target and circuit patency were evaluated clinically at 3, 6, and 12 months post-procedure.Technical success was 96% (42/44): Two participants were excluded from analysis due to the need for high-pressure balloon angioplasty as the target lesions did not efface with CBA. The median follow-up duration was 337.5 days. Mean stenosis pre- and post-angioplasty was 69.0% (51.6-84.8) and 20.8% (0-44.8), respectively. The target lesion primary, primary assisted and circuit patency for the entire study population (n = 42) were 61.6 ± 7.8%, 92.7 ± 4.0%, and 54.7 ± 7.9%, respectively, at 12 months. For participants without non-target lesions (n = 22), the rates were 77.3 ± 8.9%, 90.9 ± 6.1%, and 60.7 ± 11.0%, respectively, at 12 months.CBA followed by PCB angioplasty appears safe and feasible for treatment of recurrent venous lesions in dysfunctional AVFs.

This study investigates the free vibration responses of laminated composite sandwich beam with multi-cores using experimental and numerical methods. The laminated composite face sheets are made by using hand layup method. An experimental modal test has been carried for different configurations of multi-core sandwich beams under different end conditions. The single-core and multi-core sandwich beams has been modeled and the natural frequencies of sandwich beams are determined using ANSYS software. The numerical model is verified by comparing the obtained natural frequencies with experimental results. The numerical and experimental results indicate that the multi-core sandwich beam greatly influences the structural stiffness compared with single-core sandwich beam under different end conditions. Furthermore, the influence of several parameters such as the end conditions, thickness of the core layer, and stacking sequence on the natural frequencies of the various configurations of the multi-core sandwich beams are presented.

To perform an individual patient data level meta-analysis of randomised controlled trials comparing drug coated balloon angioplasty (DCB) against conventional percutaneous transluminal angioplasty (PTA) in the treatment of dysfunctional haemodialysis venous access.A search was conducted from inception to 13 November 2020. Kaplan-Meier curves comparing DCB with PTA by target lesion primary patency (TLPP) and access circuit primary patency (ACPP) were graphically reconstructed to retrieve patient level data. One stage meta-analyses with Cox models with random effects shared frailties were conducted to determine hazard ratios (HRs). Dynamic restricted mean survival times (RMST) were conducted in view of violation of the proportional hazards assumption. Conventional two stage meta-analyses and network meta-analyses under random effects Frequentist models were conducted to determine overall and comparative outcomes of paclitaxel concentrations used. Where outliers were consistently detected through outlier and influence analyses, sensitivity analyses excluding those studies were conducted.Among 10 RCTs (1 207 patients), HRs across all models favoured DCB (one stage shared frailty HR 0.62, 95% CI 0.53 - 0.73, p.001; two stage random effects HR 0.60, 95% CI 0.42 - 0.86, p = .018, IOverall evidence suggests that DCB is favoured over PTA in TLPP and ACPP.

BACKGROUND: Moyamoya syndrome (MMS) is a relatively uncommon vascular complication of sickle cell disease (SCD) characterized by progressive stenosis of the supraclinoid carotid arteries and development of typical collaterals. MMS confers a signicant lifetime risk of ischemic stroke, and frequently results in multiple cerebrovascular events leading to poor outcomes. Management of MMS in this population is challenging. Ischemic stroke develops in 7% to 11% of children with homozygous sickle cell anemia (HbSS) CLINICAL DESCRIPTION: We present a case of Moyamoya syndrome disease that was detected in a 7-year-old female who presented with transient altered mental status &leftsided hemiparesis. On MR angiography and further investigation, the child was diagnosed to have Moyamoya diseases with sickle cell disease. MANAGEMENT: Although there is no denitive medicaltreatment, numerous direct and indirect revascularization procedures have been used to improve the compromisedcerebral circulation, with outcomes varying according to procedure type, the treatment goal is toimprove blood ow to hypoperfused cerebral regions bysurgery. Our patient was treated conservatively and referred to a higher Centre for specic neurosurgery. Neurosurgical revascularization process leads to favorable outcome. CONCLUSION: Moyamoya disease can be diagnosed if history, physical exam and brain imaging is highly suspicious. Conventional angiography remains the gold standard for diagnosis and aids in surgical planning for patients with suspected Moyamoya disease

Background & Aims Biannual ultrasound has poor sensitivity for hepatocellular carcinoma (HCC) screening. MRI is accurate for the detection of HCC, but a complete MRI is not feasible as a screening tool. Abbreviated MRI (AMRI) is an acceptable alternative. The diagnostic performance of different AMRI protocols is not known. We performed a systematic review to determine the diagnostic accuracy of AMRI for HCC screening. Methods We searched the MEDLINE and EMBASE databases for studies reporting the diagnostic accuracy of AMRI for HCC screening. The pooled sensitivity and specificity of different AMRI protocols were calculated based on a random intercept logistic regression model. The diagnostic performance of AMRI was compared with ultrasound. Study quality was assessed using the QUADAS-2 tool. Results Of the 11,327 studies screened by titles, 15 studies (3 prospective and 12 retrospective: 2,807 patients, 917 with HCC) were included in the final analysis. The pooled per-patient sensitivity and specificity were 86% (95% CI 84–88%, I2 0%) and 94% (95% CI 91–96%, I2 83%), respectively. Pooled per-lesion sensitivity was 77% (95% CI 74–81%, I2 8%). There was no influence of study type, screening setting, reference standard, and presence and etiology of cirrhosis on the performance of AMRI. The sensitivity of AMRI for detection of HCC Conclusions AMRI has high sensitivity and specificity for HCC screening. Different AMRI protocols have comparable diagnostic performance. Lay summary Abbreviated MRI (AMRI) has been suggested as an alternative to ultrasound and complete MRI for hepatocellular carcinoma (HCC) screening. Our study results showed that AMRI has a high per-patient and per-lesion sensitivity for HCC. Although the sensitivity of AMRI for detection of HCC

Background Dysfunction of arteriovenous fistula (AVF) remains a significant morbidity for patients who are suffering from end-stage-kidney-disease (ESKD). The primary cause of dysfunction in AVF is due to stenosis from neointimal hyperplasia. Plain old balloon angioplasty (POBA) has been the standard of care for the treatment of AVF stenosis however the average patency rates remain poor. Drug-coated balloon (DCB) represents an emerging alternative to POBA in prolonging the patency of AV access. Paclitaxel-coated balloon (PCB) is currently the most widely studied DCB as compared to second generation DCB, sirolimus-coated balloon (SCB). Methods This is a single center, prospective and retrospective double arm registry study that is investigator driven to compare the efficacy and safety of the two DCBs in the real-world setting in Singapore. A total of 200 eligible participants will be recruited and followed-up for 12-months. The primary endpoint is the patency rates at 6-month while the secondary endpoints are the patency rates and the number of repeat interventions needed to maintain patency at 6-and 12-months. Discussion Drug-coated balloon is an emerging device in endovascular intervention of AV access. PCB was the most used DCB, until its safety concern was raised recently due to the findings of increasing risk of death following application of PCB in femoro-popliteal artery of the leg. Compared to paclitaxel, sirolimus is cytostatic in its action with a high safety margin and has anti-inflammatory effects. It has a high transfer rate to the vessel wall and effectively inhibits neointimal hyperplasia. There have not been head-to-head comparison of PCB and SCB in the treatment of dysfunctional AV access; hence through this study, we will be able to study the safety and efficacy of the two DCBs in the real-world setting. Trial registration: ClinicalTrials.gov Identifier: NCT05333640 on 19 April 2022

Pulsed electric field therapy is a novel non-invasive approach for cancer therapy. It serves as a cell permeability enhancing agent for cancer treatment. Nanosecond, high-electrical field pulse power technology is used for delivering variable, controllable, intracellular electrical perturbations in several biological systems. Here, we investigated the effect of nanosecond (ns) electric pulse (nsEP) as a therapeutic tool for cancer. In in-vitro study, the breast cancer cells (MCF-7) were exposed with electric field of ~18kV/cm intensity, ~25ns duration, at 1.5Hz in a 2mm electroporation cuvette. Post exposure, observation shows a significant reduction in cell viability. It was evident that after treatment the viability of MCF-7 cancer cells at 630 pulses are remains ~38% only. The optical microscopic analysis of MCF-7 cells shows cell morphology changes after electrical pulse exposure. Moreover, we have also investigated a comparative study of the effect nano-second electrical pulses on MCF-7 cells and Chinese Hamster Ovary (CHO) cell line. The comparative study, demonstrated that the effect of nsEPF on MCF-7 is more destructive than on CHO cell line. The obtained results support that the pulse electrical field of nanosecond (ns) duration therapy would be a potential solution for cancer treatment. Keywords: Nanosecond Pulse Electric Field; Full Width at Half Maxima; Pulse Forming Line; Pulse Exposure; Viability

Background: Parasympathomimetic reflexes are reported in literature in spine surgery. Our primary hypothesis is proposed that nociceptive stimuli can be elicited by various maneuvers of lumbar spinal surgery and the physiological manifestation depends on many patient variables and anesthesia. However, a sympathomimetic pathological response is indicative of potential neural damages, which may or may not be reversible. A spino-cardiac protective reflex (SPR), as a new entity for lumbar spinal surgery, is proposed. Study Design: This was a prospective single institution. Materials and Methods: All the patients who were undergoing single motion segment transforaminal lumbar interbody fusion (TLIF) in our institute for lumbar disc herniation or non-discogenic lumbar stenosis lumbar spinal stenosis were included who fitted into inclusion criteria till 200 subjects were recruited. Patients’ pertinent vital data were collected at clinical first pre-operative visit and preoperatively on admission. The intraoperative parameters were recorded: Pre-induction, post-induction, post-positioning, before skin incision, after skin/subcutaneous exposure, pre-screw insertion, after screw insertion, after rod connection and distraction, during central decompression-laminotomy/laminectomy, during lateral recess decompression, discectomy, and segmental compression. Significant pulse rate (PR) and mean arterial pressure (MAP) changes were monitored and correlated. Results: In the enrolled 200 patients, the change in mean MAP and PR changes in varying steps of TLIF was not significant. The positivity of a significant change in MAP and PR correlating with an evident manipulative/pathological-demographic cause was noted (plausibility), which could revert back to baseline (reversibility) after addressing the culprit in 22 cases. Non-correlating raise was also noted in 35 cases. Conclusion: Spino-protective reflex exists like any reflex in body. Prospective study on huge database needs to be done to validate these observations. However, this study does make the surgeon think for finding clues to neurological damage or left out residual compressions which can be identified and rectified in real time in many cases. INOM is the standard of care and SPR should be compared with intraoperative neuromonitoring to identify sensitivity and threshold of pathological response in future studies. Keywords: Lumbar, Protective, Reflex, Spine, Sympathomimetic, Transforaminal lumbar interbody fusion

Mucopolysacchridosis (MPS) are a clinically heterogeneous group of erratic metabolic disorders referred to as lysosomal storage disorders (LSDs). MPS disorders rise owed to deciencies in enzymes that break down glycosaminoglycans (GAGs). [1, 2, 3] The build-up of GAGs, both directly or indirectly, reason of reformist damage to cells, tissues and various organ systems and consequence in severe morbidity and condensed life expectancy. [4, 5] Clinical features that are mutual to all MPS disorders include skeletal and joint abnormalities, dysfunction in vision and hearing, cardiorespiratory problems, hepatosplenomegaly and coarse features. The central nervous system changes are characteristic of some of these disorders, with typical imaging ndings which involves white matter lesions, hydrocephalus, cervical spinal canal stenosis and bone abnormalities of the skull and spine. [6] MPS type IVA or Morquio A syndrome is an autosomal recessive MPS disorder caused by a decit of the N-acetylgalactosamine-6-sulfatase (GALNS) enzyme, which damages lysosomal degradation of keratan sulphate and chondroitin-6-sulphate.

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic disease. Tumors are poorly immunogenic and immunosuppressive, preventing T cell activation in the tumor microenvironment. Here, we present a microbial-based immunotherapeutic treatment for selective delivery of an immunogenic tetanus toxoid protein (TT856-1313) into PDAC tumor cells by attenuatedListeria monocytogenes. This treatment reactivated preexisting TT-specific memory T cells to kill infected tumor cells in mice. Treatment of KrasG12D,p53R172H, Pdx1-Cre (KPC) mice withListeria-TT resulted in TT accumulation inside tumor cells, attraction of TT-specific memory CD4 T cells to the tumor microenvironment, and production of perforin and granzyme B in tumors. Low doses of gemcitabine (GEM) increased immune effects ofListeria-TT, turning immunologically cold into hot tumors in mice. In vivo depletion of T cells fromListeria-TT + GEM–treated mice demonstrated a CD4 T cell–mediated reduction in tumor burden. CD4 T cells from TT-vaccinated mice were able to kill TT-expressing Panc-02 tumor cells in vitro. In addition, peritumoral lymph node–like structures were observed in close contact with pancreatic tumors in KPC mice treated withListeria-TT orListeria-TT + GEM. These structures displayed CD4 and CD8 T cells producing perforin and granzyme B. Whereas CD4 T cells efficiently infiltrated the KPC tumors, CD8 T cells did not.Listeria-TT + GEM treatment of KPC mice with advanced PDAC reduced tumor burden by 80% and metastases by 87% after treatment and increased survival by 40% compared to nontreated mice. These results suggest thatListeria-delivered recall antigens could be an alternative to neoantigen-mediated cancer immunotherapy.

Spine metastases are very common in cancer patients often requiring urgent assessment and the initiation of therapy. Treatment paradigms have changed exponentially over the past decade with the evolution and integration of stereotactic body radiotherapy, minimally invasive spine techniques, and systemic options including biologics and checkpoint inhibitors. These advances necessitate multidisciplinary assessments and interventions to optimize outcomes. The NOMS framework provides a mechanism for all practitioners to evaluate the 4 sentinel assessments required to make decisions in patients with spine metastases: Neurologic, Oncologic, Mechanical Stability, and Systemic disease. The NOMS framework is continuously updated with the integration of newer technologies and evidence-based medicine as they become available. This paper presents the current iteration of NOMS with a focus on the role of medical and neuro-oncologists in the assessment and treatment of metastatic spine tumors.

Introduction: To evaluate the mid-term outcomes of regular surveillance venography with or without percutaneous transluminal angioplasty in haemodialysis patients presenting with central venous occlusive disease. Materials and Methods: A single-centre retrospective analysis of haemodialysis patients who presented with central vein occlusion (CVO) and central vein stenosis (CVS) between January 2008 and December 2011 was performed. CVO and significant CVS were defined as 100% and >50% luminal narrowing respectively. Upon successful angioplasty on first presentation, patients were followed up with regular surveillance venography within 3–6 months of the intervention and were re-treated when a significant stenosis or occlusion was demonstrated. Data on patient’s demographics, comorbidities, presenting symptoms, type of upper limb dialysis access, lesion characteristics and complications were collected. Technical success, primary patency and primary assisted patency were analysed. Results: Thirty-five patients with CVO and 77 patients with CVS were enrolled. The technical success of initial PTA was 77% and 73% for the CVO and CVS groups, respectively. The primary patency at 3 months was 65% and 55% for the CVO group and CVS group, respectively (P = 0.32). The primary assisted patency at 1 year was 88% and 99% for the CVO group and CVS group, respectively (P = 0.009). At 2 years, the primary assisted patency were 77% and 90%, respectively (P = 0.07). There was significant difference in the overall primary assisted patency (P = 0.048) between the CVO and CVS groups. Conclusion: CVOs are more difficult to treat than CVS. High primary assisted patency rates can be achieved with surveillance venography, albeit at the expense of increased number of interventions. Further cost effectiveness studies need to be performed to study the true benefit of our surveillance programme. Ann Acad Med Singapore 2020;49:360–66 Key words: Dialysis circuit, End stage renal failure, Renal replacement therapy