Minimal Additional Risk Research Articles

OBESITY IN CHILDREN AS A PREDICTOR OF THE DEVELOPMENT OF MYOPIA

Despite a suffi cient number of scientifi c studies devoted to the study of myopia risk factors, the infl uence of obesity on the degree of myopia risk in childhood has not been suffi ciently studied, which prompted us to study this issue using children as an example. The aim is to study the frequency and degree of myopia risk in overweight and obese children.Material and Methods. The sample of children for the study was formed step by step in the process of randomization. Thefi rst stage included a one-time epidemiological study of children aged 10-18 years during preventive examinations in schools of Chernivtsi and Chernivtsi region (1,035 persons). The primary screening included anthropometry and assessment of physical development. For detailed examination 205 persons were selected: with overweight (OW, 65 persons), with obesity (75 persons) and with normal body weight (65 persons, comparison group). The ophthalmologic examination included: visometry without and with correction, autorefractokeratometry before and after cycloplegia, biomicroscopy, ophthalmoscopy, optical biometry of the eye. To reveal the statistical diff erence between indicators in normally distributed groups, the Student’s t criterion of reliability was used, the degree of signifi cance – r. Comparison of groups on a qualitative basis was performed using Pearson’s χ2 test. Diff erences were considered statistically signifi cant at p <0.05.The research design and all methods used in this study were reviewed and approved by the Bioethics Committee of theBukovinian State Medical University (Protocol No. 10, dated 18.05.2002). The study was conducted within the research work «Early diagnosis, treatment and prevention of combined pathology of gastrointestinal tract and thyroid gland in children» (state registration number 0116U002937, implementation period 02.2016-11.2022).Results. The frequency of myopia in children with OW and obesity was signifi cantly higher than in children with average body weight (χ2 = 3.2, p < 0.05). Children with obesity and myopia were 2.7 times more likely to have diseases of the musculoskeletal system, 1.8 times more likely to have pathology of the autonomic nervous system, and 3.1 times more likely to have chronic diseases of the oropharynx than children in the control group. In all groups of children, the additional risk was greatest in children whose mother or father was myopic (49.6 and 41.3 %, respectively). Minimal additional risk was associated with a history of childhood infections (<1.6 %), helminthiasis (<3.9 %), nasal polyps (<3.4 %), adenoids (<2.4 %), and spinal cord injury at birth (<9.1 %). The odds ratio for the development of low myopia in the group with OW and obesity compared to the control group (normal weight) were 1.25 [95 % CI 0.56-2.82] and 0.88 [95 % CI 0.49-1. 58], for the development of moderate myopia – 1.22 [95 % CI 0.57-2.59] and 0.82 [95 % CI 0.46-1.49], respectively, and for the development of high myopia–1.37 [95 % CI 0.51-3.66] and 0.80 [95 % CI 0.49-2.09], respectively.Conclusion. The risk of myopia is higher in children with overweight and obesity, which emphasizes the importance andnecessity of taking into account the somatic condition of the child.

(166) Surgical Excision and Grafting with Simultaneous Dorsal Plication for Ventral Plaque Accompanied by Urethral Tethering

Abstract Introduction Peyronie's disease, a condition characterized by penile curvature, approximately affects 9% of men. Surgical interventions are often employed to address this bothersome condition, and these can include techniques such as plication of the tunica albuginea, incision, or excision of the plaque with grafting procedures, and penile prosthesis implantation. The recommended treatment options vary depending on the specific constellation of symptoms and underlying conditions experienced by the patient. Objective We present a case of severe ventral curvature and penile shortening due to urethral tethering, resulting in residual curvature even after undergoing plaque excision and grafting. Methods The patient is a 65-year-old gentleman with a history of metastatic renal cell carcinoma, deep vein thrombosis status post inferior vena cava filter placement as well as anticoagulation with apixaban, and diabetes mellitus who presented with a complaint of progressive penile curvature over his past 12 months. His secondary complaints included difficulty and pain with intercourse. He noted a 90-degree ventral erection. He denies any history of penile trauma, surgery, or pelvic radiation, though he did report chest radiation for his metastatic kidney cancer. Penile doppler noted a large ventral mid penile plaque measuring 9.5x7.7x5 mm. Due to the severe, bothersome curvature, the patient was recommended excision and grafting (Tutoplast). Intraoperatively, a 2.5 cm x 3.0 cm plaque was excised and a Tutoplast pericardial allograft was used to cover the corporal defect. However, due to urethral tethering the patient still had residual curvature. We opted to perform a dorsal tunica albuginea plication using the Lue 16 dot technique. Results Penile plication remains a tool in the armamentarium of the reconstructive urologist and andrologist for penile curvature arising from Peyronie’s disease. However, in the setting of severe curvature, the penile length loss arising from plication alone can be prohibitive. Therefore incision, or excision with grafting has been implemented with significant sparing of penile length. On the other hand, there is a limit to which length can be maintained and occasionally the tethering of the corpus spongiosum can result in residual curvature. Contralateral tunical plication is therefore an option to be performed concomitantly with grafting procedures. This combination is uncommon but has been reported. In our approach, the patient’s severe curvature was improved with ventral plaque excision and grafting. However, his residual curvature at this stage was able to be corrected with minimal effect on his penile length by applying a dorsal plication technique with minimal additional risk. During the follow-up after the surgery, the patient reported a smooth recovery without any complications. There was no residual curvature, and the patient was able to achieve normal erections sufficient for intercourse without the need for additional measures. Conclusions The correction of severe ventral curvature deformity can be challenging, the surgeon should be prepared to perform additional correction procedures if penile straightening was limited by the tethering of the neurovascular bundle or urethra. Excision and grafting of ventral plaque with concomitant dorsal tunica plication for residual curvature in settings of urethral tethering is a safe viable and effective option with excellent functional results. Disclosure No.

(191) Excision and Grafting with Concomitant Dorsal Plication for Ventral Plaque with Urethral Tethering

Abstract Introduction Peyronie's disease, a condition characterized by penile curvature, approximately affects 9% of men. Surgical interventions are often employed to address this bothersome condition, and these can include techniques such as plication of the tunica albuginea, incision or excision of the plaque with grafting procedures, and penile prosthesis implantation. The recommended treatment options vary depending on the specific constellation of symptoms and underlying conditions experienced by the patient. Objective We present a case of severe ventral curvature and penile shortening due to urethral tethering, resulting in residual curvature even after undergoing plaque excision and grafting. Methods The patient is a 65-year-old gentleman with a history of metastatic renal cell carcinoma, deep vein thrombosis status post inferior vena cava filter placement as well as anticoagulation with apixaban, and diabetes mellitus who presented with a complaint of progressive penile curvature over his past 12 months. His secondary complaints included difficulty and pain with intercourse. He noted a 90-degree ventral erection. He denies any history of penile trauma, surgery, or pelvic radiation, though he did report chest radiation for his metastatic kidney cancer. Penile doppler noted a large ventral mid penile plaque measuring 9.5x7.7x5 mm. Due to the severe, bothersome curvature, the patient was recommended excision and grafting (Tutoplast). Intraoperatively, a 2.5 cm x 3.0 cm plaque was excised and a Tutoplast pericardial allograft was used to cover the corporal defect. However, due to urethral tethering the patient still had residual curvature. We opted to perform a dorsal tunica albuginea plication using the Lue 16 dot technique. Results Penile plication remains a tool in the armamentarium of the reconstructive urologist and andrologist for penile curvature arising from Peyronie’s disease. However, in the setting of severe curvature, the penile length loss arising from plication alone can be prohibitive. Therefore incision, or excision with grafting has been implemented with significant sparing of penile length. On the other hand, there is a limit to which length can be maintained and occasionally the tethering of the corpus spongiosum can result in residual curvature. Contralateral tunical plication is therefore an option to be performed concomitantly with grafting procedures. This combination is uncommon but has been reported. In our approach, the patient’s severe curvature was improved with ventral plaque excision and grafting. However, his residual curvature at this stage was able to be corrected with minimal effect on his penile length by applying a dorsal plication technique with minimal additional risk. During the follow-up after the surgery, the patient reported a smooth recovery without any complications. There was no residual curvature, and the patient was able to achieve normal erections sufficient for intercourse without the need for additional measures. Conclusions The correction of severe ventral curvature deformity can be challenging, the surgeon should be prepared to perform additional correction procedures if penile straightening was limited by the tethering of the neurovascular bundle or urethra. Excision and grafting of ventral plaque with concomitant dorsal tunica plication for residual curvature in settings of urethral tethering is a safe viable and effective option with excellent functional results. Disclosure No.

Migrating Whooping Cranes avoid wind-energy infrastructure when selecting stopover habitat.

Electricity generation from renewable-energy sources has increased dramatically worldwide in recent decades. Risks associated with wind-energy infrastructure are not well understood for endangered Whooping Cranes (Grus americana) or other vulnerable Crane populations. From 2010 to 2016, we monitored 57 Whooping Cranes with remote-telemetry devices in the United States Great Plains to determine potential changes in migration distribution (i.e., avoidance) caused by presence of wind-energy infrastructure. During our study, the number of wind towers tripled in the Whooping Crane migration corridor and quadrupled in the corridor's center. Median distance of Whooping Crane locations from nearest wind tower was 52.1km, and 99% of locations were >4.3km from wind towers. A habitat selection analysis revealed that Whooping Cranes used areas ≤5.0km (95% confidence interval [CI]4.8-5.4) from towers less than expected (i.e., zone of influence) and that Whooping Cranes were 20 times (95% CI 14-64) more likely to use areas outside compared to adjacent to towers. Eighty percent of Whooping Crane locations and 20% of wind towers were located in areas with the highest relative probability of Whooping Crane use based on our model, which comprised 20% of the study area. Whooping Cranes selected for these places, whereas developers constructed wind infrastructure at random relative to desirable Whooping Crane habitat. As of early 2020, 4.6% of the study area and 5.0% of the highest-selected Whooping Crane habitat were within the collective zone of influence. The affected area equates to habitat loss ascribed to wind-energy infrastructure; losses from other disturbances have not been quantified. Continued growth of the Whooping Crane population during this period of wind infrastructure construction suggests no immediate population-level consequences. Chronic or lag effects of habitat loss are unknown but possible for long-lived species. Preferentially constructing future wind infrastructure outside of the migration corridor or inside of the corridor at sites with low probability of Whooping Crane use would allow for continued wind-energy development in the Great Plains with minimal additional risk to highly selected habitat that supports recovery of this endangered species.

The effectiveness of social bubbles as part of a Covid-19 lockdown exit strategy, a modelling study.

Background: ​ During the coronavirus disease 2019 (COVID-19) lockdown, contact clustering in social bubbles may allow extending contacts beyond the household at minimal additional risk and hence has been considered as part of modified lockdown policy or a gradual lockdown exit strategy. We estimated the impact of such strategies on epidemic and mortality risk using the UK as a case study. Methods: ​ We used an individual based model for a synthetic population similar to the UK, stratified into transmission risks from the community, within the household and from other households in the same social bubble. The base case considers a situation where non-essential shops and schools are closed, the secondary household attack rate is 20% and the initial reproduction number is 0.8. We simulate social bubble strategies (where two households form an exclusive pair) for households including children, for single occupancy households, and for all households. We test the sensitivity of results to a range of alternative model assumptions and parameters. Results: Clustering contacts outside the household into exclusive bubbles is an effective strategy of increasing contacts while limiting the associated increase in epidemic risk. In the base case, social bubbles reduced fatalities by 42% compared to an unclustered increase of contacts. We find that if all households were to form social bubbles the reproduction number would likely increase to above the epidemic threshold of R=1. Strategies allowing households with young children or single occupancy households to form social bubbles increased the reproduction number by less than 11%. The corresponding increase in mortality is proportional to the increase in the epidemic risk but is focussed in older adults irrespective of inclusion in social bubbles. Conclusions: ​ If managed appropriately, social bubbles can be an effective way of extending contacts beyond the household while limiting the increase in epidemic risk.

The effectiveness of social bubbles as part of a Covid-19 lockdown exit strategy, a modelling study

Background: ​ During the coronavirus disease 2019 (COVID-19) lockdown, contact clustering in social bubbles may allow extending contacts beyond the household at minimal additional risk and hence has been considered as part of modified lockdown policy or a gradual lockdown exit strategy. We estimated the impact of such strategies on epidemic and mortality risk using the UK as a case study. Methods: ​ We used an individual based model for a synthetic population similar to the UK, stratified into transmission risks from the community, within the household and from other households in the same social bubble. The base case considers a situation where non-essential shops and schools are closed, the secondary household attack rate is 20% and the initial reproduction number is 0.8. We simulate social bubble strategies (where two households form an exclusive pair) for households including children, for single occupancy households, and for all households. We test the sensitivity of results to a range of alternative model assumptions and parameters. Results: Clustering contacts outside the household into exclusive bubbles is an effective strategy of increasing contacts while limiting the associated increase in epidemic risk. In the base case, social bubbles reduced fatalities by 42% compared to an unclustered increase of contacts. We find that if all households were to form social bubbles the reproduction number would likely increase to above the epidemic threshold of R=1. Strategies allowing households with young children or single occupancy households to form social bubbles increased the reproduction number by less than 11%. The corresponding increase in mortality is proportional to the increase in the epidemic risk but is focussed in older adults irrespective of inclusion in social bubbles. Conclusions: ​ If managed appropriately, social bubbles can be an effective way of extending contacts beyond the household while limiting the increase in epidemic risk.

The effectiveness of social bubbles as part of a Covid-19 lockdown exit strategy, a modelling study.

Background: ​ During the coronavirus disease 2019 (COVID-19) lockdown, contact clustering in social bubbles may allow extending contacts beyond the household at minimal additional risk and hence has been considered as part of modified lockdown policy or a gradual lockdown exit strategy. We estimated the impact of such strategies on epidemic and mortality risk using the UK as a case study. Methods: ​ We used an individual based model for a synthetic population similar to the UK, stratified into transmission risks from the community, within the household and from other households in the same social bubble. The base case considers a situation where non-essential shops and schools are closed, the secondary household attack rate is 20% and the initial reproduction number is 0.8. We simulate social bubble strategies (where two households form an exclusive pair) for households including children, for single occupancy households, and for all households. We test the sensitivity of results to a range of alternative model assumptions and parameters. Results: Clustering contacts outside the household into exclusive bubbles is an effective strategy of increasing contacts while limiting the associated increase in epidemic risk. In the base case, social bubbles reduced fatalities by 42% compared to an unclustered increase of contacts. We find that if all households were to form social bubbles the reproduction number would likely increase to above the epidemic threshold of R=1. Strategies allowing households with young children or single occupancy households to form social bubbles increased the reproduction number by less than 11%. The corresponding increase in mortality is proportional to the increase in the epidemic risk but is focussed in older adults irrespective of inclusion in social bubbles. Conclusions: ​ If managed appropriately, social bubbles can be an effective way of extending contacts beyond the household while limiting the increase in epidemic risk.

Asymptotics of multivariate conditional risk measures for Gaussian risks

This paper investigates accurate approximations of marginal moment excess, marginal conditional tail moment and marginal moment shortfall for multivariate Gaussian system risks. Based on the dimension reduction property via the quadratic programming problem, the super-exponential and polynomial convergence speeds are specified. Two interesting questions involved in risk management are well addressed, namely the minimal additional risk capital injection to avoid infinite risk contagion and a sufficient and necessary condition to alternate the convergence speeds. Numerical study and typical examples are given to illustrate the efficiency of our findings. Due to the flexible moment order, additional applications may involve in risk management, including tail mean–variance portfolio and multivariate conditional risk measures of tail covariance, tail skewness with dependence and extremal risk contagion under consideration.

The Safety and Feasibility of Gynecologic Cancer Surgery Combined With Surgery for Pelvic Floor Dysfunction.

Women with gynecologic cancer may also present with pelvic floor dysfunction that can have a significant effect on quality of life. Combined surgical intervention for both malignancy and pelvic floor dysfunction may improve quality of life with minimal additional risk. We sought to determine the safety, feasibility, and frequency of combined gynecologic cancer surgery and surgery for pelvic floor dysfunction. This is a retrospective cohort study that utilized the National Surgical Quality Improvement Program database provided through the American College of Surgeons. The National Surgical Quality Improvement Program database was queried for patients with a final diagnosis of gynecologic malignancy from 2011 to 2015. Common Procedural Terminology codes for gynecologic oncology procedures and pelvic floor dysfunction surgery were used to identify the study population. Baseline demographics and postoperative complications were abstracted from the database for these patients and compared for patients with combined surgeries versus gynecologic cancer surgeries alone. One hundred twenty-nine women underwent combined procedures compared with 25,838 women undergoing gynecologic cancer surgery alone. Patients who underwent combined procedures were older, had lower body mass index, had higher preoperative albumin and hematocrit, and lower morbidity estimates (P < 0.05). Mean operative time was longer (226.4 vs 174.4 minutes, P < 0.01). There were no statistically significant differences in race, ethnicity, or medical comorbidities. There were no statistically significant differences in postoperative complications or readmissions between the 2 groups (P > 0.1). Combined gynecologic cancer and pelvic floor dysfunction procedures are feasible and can safely be performed without differences in postoperative complications in appropriately selected patients.

PS01.196: SHORT-TERM AND MEDIUM-TERM OUTCOMES IN PATIENTS OVER 70 DIAGNOSED WITH OESOPHAGEAL CANCER

Abstract Background Oesophageal cancer incidence has increased over the last decade in the UK, particularly in older patients. Surgery, with or without perioperative chemotherapy, remains the gold standard treatment for patients with potentially curable disease. Currently, 41% of new cases of oesophageal cancer are in patients aged over 70. However, only 10% underwent surgery compared to 25% of those aged under 70. Concerns exist that advanced age may prejudice treatment decisions. The aim of our review is to evaluate the impact of age on outcomes in those undergoing planned curative treatment for oesophageal cancer. Methods A retrospective review of patients undergoing oesophagectomy for carcinoma between 2006 to 2016 at a single institution was performed. Patients were divided into two cohorts based on age at the time of diagnosis; under 70 years (Group A) and over 70 (Group B). Patients underwent a standardised staging protocol and treatment was decided by a multi-disciplinary team. Oesophagectomy was performed using a transthoracic approach with two field lymphadenectomy and perioperative chemo (radio) therapy used in those patients with locally advanced disease who were fit enough. Results There were 555 patients in Group A and 241 in Group B. Adenocarcinoma was the prevalent histological subtype in both cohorts: 76% (423) in Group A and 68% (165) in Group B. Median age at the time of diagnosis was 62 in Group A versus 74 in Group B. In Group A, 12% (18/343) did not receive neo-adjuvant treatment for locally advanced cancer versus 47% (101/212) in Group B (P &lt; 0.001). Median hospital stay was longer in Group B (18 v 15 days P = 0.02). There was no significant difference in hospital mortality (Group A 1% vs Group B 2.4% P = 0.37) and major complication rate (Group A 14% vs Group B 20% P = 0.31). Two-year survival was 66% (adenocarcinoma) and 78% (SCC) in Group A compared to 60% (adenocarcinoma) and 64% (SCC) in Group B. Conclusion These results demonstrate that patients over 70 can be treated successfully with minimal additional risk to morbidity and mortality. However, these patients are more likely to be denied neoadjuvant treatment which may compromise their long-term outcomes. Disclosure All authors have declared no conflicts of interest.

Utilization of intraoperative neuromonitoring throughout the United States over a recent decade: an analysis of the nationwide inpatient sample.

To identify temporal changes to the demographics and utilization of intraoperative neuromonitoring (IONM) throughout the United States (U.S.). The National Inpatient Sample (NIS) database was queried for IONM of central and peripheral nervous electrical activity (ICD-9-CM 00.94) between 2008 and 2014. The NIS database represents a 20% sample of discharges from U.S. Hospitals, weighted to provide national estimates. Demographic and economic data were obtained which included the annual number of surgeries, age, sex, insurance type, location, and frequency of routine discharge. The estimated use of IONM of central and peripheral nervous electrical activity increased 296%, from 31,762 cases in 2008 to 125,835 cases in 2014. Based on payer type, privately insured patients (45.0%), rather than Medicare (36.8%) or Medicaid patients (9.2%), were more likely to undergo IONM during spinal procedures. When stratifying by median income for patient zip code, there was a substantial difference in the rates of IONM between low (19.9%) and high-income groups (78.1%). IONM was significantly more likely to be utilized at urban teaching hospitals (72.9%) rather than nonteaching hospitals (25.0%) or rural centers (2.2%). Over the last decade, there has been a massive increase of 296% in utilization of IONM during spine surgery. This is likely due to its proven benefit in reducing neurologic morbidity in spinal deformity surgery, while introducing minimal additional risk. While IONM may improve patient care, it is still rather isolated to teaching hospitals and patients from higher income zip codes.

Manipulation of contact network structure and the impact on foot-and-mouth disease transmission

The movements of livestock between premises and markets can be characterised as a dynamic network where the structure of the network itself can critically impact the transmission dynamics of many infectious diseases. As evidenced by the 2001 foot-and-mouth disease (FMD) epidemic in the UK, this can involve transmission over large geographical distances and can result in major economic loss. One consequence of the FMD epidemic was the introduction of mandatory livestock movement restrictions: a 13-day standstill in Scotland for cattle and sheep after moving livestock onto a farm (allowing many exemptions) and a 6-day standstill for cattle and sheep in England and Wales (with minor exemptions, e.g. direct movements to slaughter). Such standstills are known to be effective but commercial considerations result in pressures to relax them. When contemplating legislative changes such as a change in length of movement restrictions we need to consider the consequent effect these could have on the emergent properties of the system, i.e. the network structure itself. In this study, we investigate how disease dynamics change when the local contact structure of the recorded livestock movement network in Scotland is altered through rewiring movements between premises. The network rewiring used here changes the structure of the recorded trade network through a combination of altered movement restrictions and redirection of movements between holdings and markets to avoid nonsensical activity (e.g. movements to markets on days when they are inactive) while conserving other characteristics (e.g. movement date as closely as possible and market sales of the correct animal production type). Rewiring results in networks with higher clustering coefficients and lower network density. The impact of rewiring on a hypothetical foot-and-mouth disease outbreak in Scotland was assessed by stochastic simulation, considering scenarios with and without exemptions to the standstill rules. As expected, rewiring leads to a decrease in outbreak size and - if standstill exemptions are prohibited – higher probability of smaller outbreaks. Without exemptions, a shorter movement standstill is almost as effective as a longer standstill period, indicating that a simpler biosecurity system would offer minimal additional risk for FMD. These results suggest that explicitly manipulating the contact network structure in a sensible way has the potential to significantly impact disease control.

Advanced ultrasound applications in the assessment of renal transplants: contrast-enhanced ultrasound, elastography, and B-flow.

Ultrasound is routinely used as the first imaging exam for evaluation of renal transplants and can identify most major surgical complications and evaluate vascularity with color Doppler. Ultrasound is limited, however, in the detection of parenchymal disease processes and Doppler evaluation is also prone to technical errors. Multiple new ultrasound applications have been developed and are under ongoing investigation which could add additional diagnostic capability to the routine ultrasound exam with minimal additional time, cost, and patient risk. Contrast-enhanced ultrasound (CEUS) can be used off-label in the transplant kidney, and can assist in detection of infection, trauma, and vascular complications. CEUS also can demonstrate perfusion of the transplant assessed quantitatively with generation of time-intensity curves. Future directions of CEUS include monitoring treatment response and microbubble targeted medication delivery. Elastography is an ultrasound application that can detect changes in tissue elasticity, which is useful to diagnose diffuse parenchymal disease, such as fibrosis, otherwise unrecognizable with ultrasound. Elastography has been successfully applied in other organs including the liver, thyroid, and breast; however, it is still under development for use in the transplant kidney. Unique properties of the transplant kidney including its heterogeneity, anatomic location, and other technical factors present challenges in the development of reference standard measurements. Lastly, B-flow imaging is a flow application derived from B-mode. This application can show the true lumen size of a vessel which is useful to depict vascular anatomy and bypasses some of the pitfalls of color Doppler such as demonstration of slow flow.

What is the fate of artificial urinary sphincters among men undergoing repetitive bladder cancer treatment?

PurposeFunctional characteristics and durability of the artificial urinary sphincter (AUS) among patients who develop bladder cancer has been poorly characterized. We sought to evaluate AUS outcomes among patients subsequently diagnosed with bladder cancer, in order to describe device survivability when subject to diagnostic and therapeutic procedures such as cystoscopy, transurethral resection, and cystectomy.Materials and MethodsWe retrospectively reviewed 1,803 male patients treated with AUS surgery at a single institution between 1983–2014. We describe AUS device outcomes among patients undergoing surveillance and treatment for bladder cancer.ResultsFollowing AUS placement, 14 (0.8%) patients were subsequently diagnosed with and treated for bladder cancer and 4 patients with bladder cancer undergoing treatment and screening, subsequently received AUS placement. The median follow-up from device placement was 7.2 years (interquartile range [IQR], 2.8–11.5), and the median time from AUS placement to bladder cancer diagnosis was 6 (IQR, 0–9). There were a total of 8 primary and 1 secondary devices failures. Despite a median of 2 diagnostic cystoscopies (IQR, 1–6) and 0 bladder tumor resections (IQR, 0–0) per patient following device implantation, only 1 (5.6%) patient experienced an iatrogenic erosion related to urethral manipulation. Among those undergoing cystectomy (n=4), 1 device was left in situ without complication.ConclusionsBladder cancer surveillance and treatment with an AUS device in place appears to confer minimal additional risk to AUS survival. Careful attention should be given to device deactivation and use of the smallest caliber instruments available to minimize the risk of iatrogenic urethral erosion.

Microinvasive glaucoma surgeries

Because of the complications of current penetrating glaucoma surgeries as in trabeculectomy or glaucoma drainage devices, there is now an increased interest in newly introduced microinvasive glaucoma surgeries, which provide a safer and not a less-efficient alternative for such procedures, along with a decrease in dependence of glaucoma medications postoperatively. The microscopic implants can be implanted by following either an ab-interno approach (e.g. iStent, CyPass, Trabectome, and Xen Gel microshunt) or an ab-externo approach (e.g. Ex-Press minishunt and canaloplasty). The procedures aim to utilize the trabecular pathway, suprachoroidal space, or the subconjunctival space to increase aqueous drainage. These procedures can be performed in conjunction with phacoemulsification to augment the intraocular pressure-lowering effect, and the devices can be implanted during the same session without or with minimal additional risk.

A heuristic framework for the bi-objective enhanced index tracking problem

The index tracking problem is the problem of determining a portfolio of assets whose performance replicates, as closely as possible, that of a financial market index chosen as benchmark. In the enhanced index tracking problem the portfolio is expected to outperform the benchmark with minimal additional risk. In this paper, we study the bi-objective enhanced index tracking problem where two competing objectives, i.e., the expected excess return of the portfolio over the benchmark and the tracking error, are taken into consideration. A bi-objective Mixed Integer Linear Programming formulation for the problem is proposed. Computational results on a set of benchmark instances are given, along with a detailed out-of-sample analysis of the performance of the optimal portfolios selected by the proposed model. Then, a heuristic procedure is designed to build an approximation of the set of Pareto optimal solutions. We test the proposed procedure on a reference set of Pareto optimal solutions. Computational results show that the procedure is significantly faster than the exact computation and provides an extremely accurate approximation.

Outcomes in lung transplantation after previous lung volume reduction surgery in a contemporary cohort

Lung volume reduction surgery (LVRS) provides palliation and improved quality of life in select patients with end-stage chronic obstructive pulmonary disease (COPD). The effect of previous LVRS on lung transplant outcomes has been inadequately studied. We report our experience in the largest single institution series of these combined procedures. The records of 472 patients with COPD undergoing lung transplantation or LVRS between 1995 and 2010 were reviewed. Outcomes of patients undergoing transplant after LVRS were compared with outcomes of patients undergoing transplant or LVRS alone. Survival was compared using log-rank tests and the Kaplan-Meier method. Demographics, comorbidities, and spirometry were similar at the time of transplantation. Patients who had undergone lung transplant after LVRS had longer transplant operative times (mean 4.4 vs 5.6 hours; P=.020) and greater hospital length of stay (mean 17.6 vs 29.1 days; P=.005). Thirty-day mortality and major morbidity were similar. Posttransplant survival was reduced for transplant after LVRS (median, 49 months; 95% confidence interval [CI], 16, 85 months) compared with transplant alone (median, 96 months; 95% CI, 82, 106 months; P=.008). The composite benefit of combined procedures, defined as bridge from LVRS to transplant of 55 months and posttransplant survival of 49 months (total 104 months), was comparable with survival of patients undergoing either procedure alone. Lung transplant after LVRS leads to minimal additional perioperative risk. The reduced posttransplant survival in patients undergoing combined procedures is in contradistinction to reports from other smaller series. When determining the best surgical treatment for patients with more severe disease, the benefit ofLVRSbefore transplant should be weighed against the consequence of reduced posttransplant survival.

Abstract 18819: Clinical Outcomes Following Implantation of a Centrifugal Flow Left-Ventricular Assist Device and Concomitant Cardiac Valve Procedures

Purpose: Patients undergoing implantation of left ventricular assist devices (LVAD) often undergo concomitant cardiac valve procedures, but the added procedural risk has not been studied in detail. We reviewed patients receiving a centrifugal flow LVAD system in the ADVANCE Bridge to Transplant Trial (BTT) and Continued Access Protocol (CAP) to evaluate the impact of concomitant valve procedures on early outcomes. Methods: The ADVANCE BTT and CAP trial enrolled 381 patients (pts) through November 2012. This group was divided into two subgroups: pts who underwent a concomitant valve procedure in addition to LVAD implant (VP) and those who did not undergo a concomitant valve procedure (no VP). Preop characteristics, adverse events and Kaplan-Meier survival were compared for the two groups. Results: A total of 19.7% (75/381) of pts underwent VP at the time of LVAD implantation. The most frequent procedure was tricuspid valve repair or replacement, performed in 14.7% of pts, followed by aortic (3.4%), and mitral (2.1%) valve procedures. Patients undergoing a VP were younger and had more recent onset of heart failure. Other pre-implant variables were similar for the two groups. Length of time on cardiopulmonary bypass was increased for VP pts, but mean length of hospital stay did not differ. Proportions of pts having perioperative tamponade, bleeding, arrhythmias, or strokes were similar. VP pts had more right heart failure (RHF) requiring inotropic therapy (37.3% vs. 22.9%, P =0.01); however, there was no difference in RHF requiring RVAD support (2.7% vs. 2.6%, P =1.00). Overall Kaplan Meier survival for the two groups was similar, 97.3% VP vs. 98.0% No VP at 30 days and 88.2% VP vs. 90.5% No VP at 6 months ( P =0.57). Survival was also similar for aortic (N=13) versus tricuspid (N=56) procedures, with 6 month survival 90.0% and 88.5%, respectively ( P =0.75). Conclusion: Tricuspid repair was the most common VP. Increased post-op RHF may have reflected more pre-op right heart dysfunction in this patient subgroup. Overall, the concomitant valve group experienced very good survival, suggesting that VP can be performed at the time of LVAD implant with minimal additional risk.

Investigation of Deep Brain Stimulation Mechanisms During Implantable Pulse Generator Replacement Surgery

Direct testing of deep brain stimulation (DBS) mechanisms in humans is needed to assess therapy and to understand stimulation effects. We developed an innovative paradigm for investigation of DBS on human movement disorders. Temporary connection to the DBS electrode during implantable pulse generator (IPG) replacement permitted analysis of novel patterns of stimulation on motor symptoms, which could enhance efficacy and improve battery life. Patients enrolled in this prospective, Institutional Review Board-approved study underwent IPG replacement using local (monitored) anesthesia. Following device explant, the DBS electrode was connected to an external, isolated electrical stimulator using a sterile adapter cable. Different temporal patterns of stimulation were delivered while quantifying upper-extremity tremor (tri-axial accelerometry) or bradykinesia (finger-tapping). Upon experiment completion, the new IPG was implanted. Among 159 IPG replacements from 2005 to 2011, 56 patients agreed to the research study (16 essential tremor [ET], 31 Parkinson's disease [PD], 5 mixed ET/PD tremor, 3 multiple sclerosis, 1 tremor/myoclonus). Surgical procedures were extended by 42 ± 8.2 min in 37 patients completing the study. Motor symptoms varied with stimulation pattern, with some patterns showing improved tremor or bradykinesia control. No postoperative infections or complications were observed in the 159 patients. IPG replacement occurs when the DBS/brain interface is stable and patients demonstrate symptom reduction with known stimulation parameters. Conducting research at this time point avoids DBS implant issues, including temporary microlesion effects, fluctuating electrode impedances, and technical limitations of contemporary IPGs, providing advantageous conditions to conduct translational DBS research with minimal additional risk to research subjects.

Transesophageal echocardiography in the management of burn patients

A systematic review was conducted to assess the level of evidence for the use of transesophageal echocardiography (TEE) in the management of burn patients. We searched any article published before and including June 30, 2013. Our search yielded 118 total publications, 11 met the inclusion criteria of burn injury and TEE. Available studies published in any language were rated and included. At the present time, there are no available systematic reviews/meta-analyses published that met our search criteria. Only a small number of clinical trials, all with a limited number of patients were available. Therefore, a meta-analysis on outcome parameters was not performed. However, the major pathologic findings in burn patients were reduced left ventricular (LV) systolic and diastolic function, mitral valve vegetation, pulmonary hypertension, pericardial effusion, fluid overload, and right heart failure. The advantages of TEE include offering direct assessment of cardiac valve competency, myocardial contractility, and most importantly real time assessment of adequacy of hemodynamic resuscitation and preload in the acute phase of resuscitation, with minimal additional risk. TEE serves multiple diagnostic purposes and is being used to better understand the fluid status and cardiac physiology of the critically ill burn patient. Randomized controlled trials especially on fluid resuscitation and cardiac performance in acute burns are warranted to potentially further improve outcome.