Spatially distributed atmospheric boundary layer properties in Houston - A value-added observational dataset.

In 2022, Houston, TX became a nexus for field campaigns aiming to further our understanding of the feedbacks between convective clouds, aerosols and atmospheric boundary layer (ABL) properties. Houston's proximity to the Gulf of Mexico and Galveston Bay motivated the collection of spatially distributed observations to disentangle coastal and urban processes. This paper presents a value-added ABL dataset derived from observations collected by eight research teams over 46 days between 2 June - 18 September 2022. The dataset spans 14 sites distributed within a ~80-km radius around Houston. Measurements from three types of instruments are analyzed to objectively provide estimates of nine ABL parameters, both thermodynamic (potential temperature, and relative humidity profiles and thermodynamic ABL depth) and dynamic (horizontal wind speed and direction, mean vertical velocity, updraft and downdraft speed profiles, and dynamical ABL depth). Contextual information about cloud occurrence is also provided. The dataset is prepared on a uniform time-height grid of 1 h and 30 m resolution to facilitate its use as a benchmark for forthcoming numerical simulations and the fundamental study of atmospheric processes.

Treatment of localized hepatocellular carcinoma: resection vs. ablation vs. radiation.

Hepatocellular carcinoma (HCC) is a common malignancy with many patients presenting with local disease. As of date, the use of radiation is not included in the commonly utilized Barcelona Clinic Liver Cancer (BCLC) classification but is in the National Comprehensive Cancer Network guidelines. Radiation can volumetrically cover the entire tumor and with novel technologic advances can be administered non-invasively with excellent clinical outcomes with few adverse events. The gold standard for localized early HCC (such as BCLC-A) is resection or transplantation. In patients who are not candidates for surgical treatment, locoregional therapy should be considered as an optimal therapy for these patients. Tumor ablation techniques such as microwave ablation (MWA) and radiofrequency ablation (RFA) are excellent tools to control local disease or bridge to transplantation. Should these not be possible though then ablation with external beam radiation is also capable of yielding comparable local control and serve as a bridge to transplant without worse rates of adverse events. For tumors that meet Milan criteria for transplantation, in comparison to transarterial chemoembolization (TACE), there is considerable randomized evidence demonstrating better local control, less adverse events, better progression-free survival (PFS), and less costly. It can be utilized as a bridge in Barcelona liver class B. For larger localized tumors though (extrahepatic disease or vascular invasion like BCLC-C), stereotactic body radiation therapy (SBRT) is shown via a randomized clinical trial to have a survival benefit, local control benefit, and no worse adverse events compared to systemic therapy. In this setting, it should be considered the local consolidation standard of care.

The evolution of Big Data in neuroscience and neurology.

Neurological diseases are on the rise worldwide, leading to increased healthcare costs and diminished quality of life in patients. In recent years, Big Data has started to transform the fields of Neuroscience and Neurology. Scientists and clinicians are collaborating in global alliances, combining diverse datasets on a massive scale, and solving complex computational problems that demand the utilization of increasingly powerful computational resources. This Big Data revolution is opening new avenues for developing innovative treatments for neurological diseases. Our paper surveys Big Data's impact on neurological patient care, as exemplified through work done in a comprehensive selection of areas, including Connectomics, Alzheimer's Disease, Stroke, Depression, Parkinson's Disease, Pain, and Addiction (e.g., Opioid Use Disorder). We present an overview of research and the methodologies utilizing Big Data in each area, as well as their current limitations and technical challenges. Despite the potential benefits, the full potential of Big Data in these fields currently remains unrealized. We close with recommendations for future research aimed at optimizing the use of Big Data in Neuroscience and Neurology for improved patient outcomes. Supplementary Information: The online version contains supplementary material available at 10.1186/s40537-023-00751-2.

Effectiveness of three Vitamin D dosing protocols on raising and maintaining blood serum levels of 25-hydroxyvitamin D over a three-month period: a randomized, prospective study.

INTRODUCTION: Vitamin D has gained attention in the medical community due to its critical role in calcium homeostasis and overall bone health. No standard vitamin D dosing protocol in fracture care has been established for patients deficient in 25-hydroxyvitamin D. This prospective and randomized study aimed to find a dosing regimen that would safely achieve and maintain a therapeutic level of 25-hydroxyvitamin D in deficient patients over three months. MATERIALS AND METHODS: Between June 2016 and May 2017, 48 patients with baseline total 25-hydroxyvitamin D less than 30.0 ng/mL were randomly assigned to either group one (one dose of 100,000 international units (IU) of Vitamin D2) or group 2 (100,000 IU of Vitamin D2 once weekly for twelve weeks) or group 3 (50,000 IU of Vitamin D2 daily for ten days followed by 2,000 IU of Vitamin D3 daily for 74 days). Baseline serum levels were drawn followed by interval levels at week 2, 6 and 12. The primary outcome was to determine which protocol could achieve and maintain therapeutic levels of total 25-hydroxyvitamin D over the course of three months. Our secondary outcome was to monitor for negative side effects. RESULTS: Group 1 did not show any statistically significant increase in serum levels and had no reported side effects. There was a statistically significant increase in serum total 25-hydroxyvitamin D in group 2 between all-time points except between weeks 6 and 12. Two (12.5%) participants in group 2 reported side effects. Group 3 had the greatest change in serum levels from weeks 0 to 2 but had a significant decrease between weeks 2 and 6. No change was seen between weeks 6 and 12. Three (17.5%) participants in group 3 reported side effects. CONCLUSIONS: Group 2 sustained and maintained a satisfactory level of total 25-hydroxyvitamin D over three months without any severe side effects.

Cost-Effectiveness Analysis to Inform Randomized Controlled Trial Design in Chronic Pain Research: Methods for Guiding Decisions on the Addition of a Run-In Period.

Introduction: Run-In (RI) periods can be used to improve the validity of randomized controlled trials (RCTs), but their utility in Chronic Pain (CP) RCTs is debated. Cost-effectiveness analysis (CEA) methods are commonly used in evaluating the results of RCTs, but they are seldom used for designing RCTs. We present a step-by-step overview to objectively design RCTs via CEA methods and specifically determine the cost effectiveness of a RI period in a CP RCT. Methods: We applied the CEA methodology to data obtained from several noninvasive brain stimulation CP RCTs, specifically focusing on (1) defining the CEA research question, (2) identifying RCT phases and cost ingredients, (3) discounting, (4) modeling the stochastic nature of the RCT, and (5) performing sensitivity analyses. We assessed the average cost-effectiveness ratios and incremental cost effectiveness ratios of varied RCT designs and the impact on cost-effectiveness by the inclusion of a RI period vs. No-Run-In (NRI) period. Results: We demonstrated the potential impact of varying the number of institutions, number of patients that could be accommodated per institution, cost and effectiveness discounts, RCT component costs, and patient adherence characteristics on varied RI and NRI RCT designs. In the specific CP RCT designs that we analyzed, we demonstrated that lower patient adherence, lower baseline assessment costs, and higher treatment costs all necessitated the inclusion of an RI period to be cost-effective compared to NRI RCT designs. Conclusions: Clinical trialists can optimize CP RCT study designs and make informed decisions regarding RI period inclusion/exclusion via CEA methods.

Major vascular reconstruction in colorectal adenocarcinoma and retroperitoneal sarcoma: A retrospective study of safety and margins in a tertiary referral centre.

BACKGROUND: The role of en bloc vascular resection and reconstruction (EVRR) is controversial in colorectal adenocarcinoma (CRC), but well-established in retroperitoneal sarcoma (RPS). Sparse data exists regarding these complex procedures. METHODS: Patients undergoing curative intent EVRR for advanced CRC and RPS between 2014 and 2021 at a tertiary centre were included. Morbidity, margins, recurrence, and survival were evaluated. RESULTS: 24 patients underwent EVRR with 48 reconstructions (11 CRC and 13 RPS). For CRC, 100% of patients underwent Iliac system reconstructions. For RPS, inferior vena cava reconstructions were the most common (69.2%). There were 2 arterial and 1 venous graft thromboses. Primary graft patency was 89.4% arterial and 93.1% venous, while secondary patency was 100% arterial and 96.5% venous at last follow up. 1 venous and 1 arterial graft required reoperation for bleeding. There were no compromised limbs. Major complications occurred in 6 patients (25.0%) with no observed difference between CRC and RPS (OR 0.43 95%CI[0.60,3.19], P = 0.41). R1 margins occurred 1 CRC (90.9%) and 3 RPS (76.9%), with no R2 resections. All vascular resection margins were clear. There were 6 CRC (50%) and 4 RPS (33.3%) recurrences. Median recurrence time was 20.9 months for CRC and 'not yet reached' for RPS. Median follow-up was 19.4 months for CRC and 21.4 months for RPS. CONCLUSION: EVRR for locally advanced CRC or RPS is safe and achieves favorable R0 resection rates. CRC patients with major vascular invasion can still be considered for curative intent surgery. Larger cohorts with longer follow up are needed to assess oncologic outcomes.

Monte Carlo modeling of the Elekta Versa HD and patient dose calculation with EGSnrc/BEAMnrc.

INTRODUCTION: Numerous studies have proven the Monte Carlo method to be an accurate means of dose calculation. Although there are several commercial Monte Carlo treatment planning systems (TPSs), some clinics may not have access to these resources. We present a method for routine, independent patient dose calculations from treatment plans generated in a commercial TPS with our own Monte Carlo model using free, open-source software. MATERIALS AND METHODS: A model of the Elekta Versa HD linear accelerator was developed using the EGSnrc codes. A MATLAB script was created to take clinical patient plans and convert the DICOM RTP files into a format usable by EGSnrc. Ten patients' treatment plans were exported from the Monaco TPS to be recalculated using EGSnrc. Treatment simulations were done in BEAMnrc, and doses were calculated using Source 21 in DOSXYZnrc. Results were compared to patient plans calculated in the Monaco TPS and evaluated in Verisoft with a gamma criterion of 3%/2 mm. RESULTS: Our Monte Carlo model was validated within 1%/1-mm accuracy of measured percent depth doses and profiles. Gamma passing rates ranged from 82.1% to 99.8%, with 7 out of 10 plans having a gamma pass rate over 95%. Lung and prostate patients showed the best agreement with doses calculated in Monaco. All statistical uncertainties in DOSXYZnrc were less than 3.0%. CONCLUSION: A Monte Carlo model for routine patient dose calculation was successfully developed and tested. This model allows users to directly recalculate DICOM RP files containing patients' plans that have been exported from a commercial TPS.

Frail patients having vascular surgery during the early COVID-19 pandemic experienced high rates of adverse perioperative events and amputation.

BACKGROUND: Frailty predicts adverse perioperative outcomes and increased mortality in patients having vascular surgery. Frailty assessment is a potential tool to inform resource allocation, and shared decision-making about vascular surgery in the resource constrained COVID-19 pandemic environment. This cohort study describes the prevalence of frailty in patients having vascular surgery and the association between frailty, mortality and perioperative outcomes. METHODS: The COVID-19 Vascular Service in Australia (COVER-AU) prospective cohort study evaluates 30-day and six-month outcomes for consecutive patients having vascular surgery in 11 Australian vascular units, March-July 2020. The primary outcome was mortality, with secondary outcomes procedure-related outcomes and hospital utilization. Frailty was assessed using the nine-point visual Clinical Frailty Score, scores of 5 or more considered frail. RESULTS: Of the 917 patients enrolled, 203 were frail (22.1%). The 30 day and 6 month mortality was 2.0% (n = 20) and 5.9% (n = 35) respectively with no significant difference between frail and non-frail patients (OR 1.68, 95%CI 0.79-3.54). However, frail patients stayed longer in hospital, had more perioperative complications, and were more likely to be readmitted or have a reoperation when compared to non-frail patients. At 6 months, frail patients had twice the odds of major amputation compared to non-frail patients, after adjustment (OR 2.01; 95% CI 1.17-3.78), driven by a high rate of amputation during the period of reduced surgical activity. CONCLUSION: Our findings highlight that older, frail patients, experience potentially preventable adverse outcomes and there is a need for targeted interventions to optimize care, especially in times of healthcare stress.

Electroencephalography Signatures for Conditioned Pain Modulation and Pain Perception in Nonspecific Chronic Low Back Pain-An Exploratory Study.

Conditioned pain modulation (CPM) can discriminate between healthy and chronic pain patients. However, its relationship with neurophysiological pain mechanisms is poorly understood. Brain oscillations measured by electroencephalography (EEG) might help gain insight into this complex relationship. OBJECTIVE: To investigate the relationship between CPM response and self-reported pain intensity in non-specific chronic low back pain (NSCLBP) and explore respective EEG signatures associated to these mechanisms. DESIGN: Cross-sectional analysis. PARTICIPANTS: Thirty NSCLBP patients participated. METHODS: Self-reported low back pain, questionnaires, mood scales, CPM (static and dynamic quantitative sensory tests), and resting surface EEG data were collected and analyzed. Linear regression models were used for statistical analysis. RESULTS: CPM was not significantly correlated with self-reported pain intensity scores. Relative power of EEG in the beta and high beta bands as recorded from the frontal, central, and parietal cortical areas were significantly associated with CPM. EEG relative power at delta and theta bands as recorded from the central area were significantly correlated with self-reported pain intensity scores while controlling for self-reported depression. CONCLUSIONS: Faster EEG frequencies recorded from pain perception areas may provide a signature of a potential cortical compensation caused by chronic pain states. Slower EEG frequencies may have a critical role in abnormal pain processing.

On the evaluation of mobile target trajectory between four-dimensional computer tomography and four-dimensional cone-beam computer tomography.

PURPOSE: For mobile lung tumors, four-dimensional computer tomography (4D CT) is often used for simulation and treatment planning. Localization accuracy remains a challenge in lung stereotactic body radiation therapy (SBRT) treatments. An attractive image guidance method to increase localization accuracy is 4D cone-beam CT (CBCT) as it allows for visualization of tumor motion with reduced motion artifacts. However, acquisition and reconstruction of 4D CBCT differ from that of 4D CT. This study evaluates the discrepancies between the reconstructed motion of 4D CBCT and 4D CT imaging over a wide range of sine target motion parameters and patient waveforms. METHODS: A thorax motion phantom was used to examine 24 sine motions with varying amplitudes and cycle times and seven patient waveforms. Each programmed motion was imaged using 4D CT and 4D CBCT. The images were processed to auto segment the target. For sine motion, the target centroid at each phase was fitted to a sinusoidal curve to evaluate equivalence in amplitude between the two imaging modalities. The patient waveform motion was evaluated based on the average 4D data sets. RESULTS: The mean difference and root-mean-square-error between the two modalities for sine motion were -0.35 ± 0.22 and 0.60 mm, respectively, with 4D CBCT slightly overestimating amplitude compared with 4D CT. The two imaging methods were determined to be significantly equivalent within ±1 mm based on two one-sided t tests (p < 0.001). For patient-specific motion, the mean difference was 1.5 ± 2.1 (0.8 ± 0.6 without outlier), 0.4 ± 0.3, and 0.8 ± 0.6 mm for superior/inferior (SI), anterior/posterior (AP), and left/right (LR), respectively. CONCLUSION: In cases where 4D CT is used to image mobile tumors, 4D CBCT is an attractive localization method due to its assessment of motion with respect to 4D CT, particularly for lung SBRT treatments where accuracy is paramount.

Characterization of ground-based atmospheric pollution and meteorology sampling stations during the Lake Michigan Ozone Study 2017.

The Lake Michigan Ozone Study 2017 (LMOS 2017) in May and June 2017 enabled study of transport, emissions, and chemical evolution related to ozone air pollution in the Lake Michigan airshed. Two highly instrumented ground sampling sites were part of a wider sampling strategy of aircraft, shipborne, and ground-based mobile sampling. The Zion, Illinois site (on the coast of Lake Michigan, 67 km north of Chicago) was selected to sample higher NOx air parcels having undergone less photochemical processing. The Sheboygan, Wisconsin site (on the coast of Lake Michigan, 211 km north of Chicago) was selected due to its favorable location for the observation of photochemically aged plumes during ozone episodes involving southerly winds with lake breeze. The study encountered elevated ozone during three multiday periods. Daytime ozone episode concentrations at Zion were 60 ppb for ozone, 3.8 ppb for NOx, 1.2 ppb for nitric acid, and 8.2 µg m-3 for fine particulate matter. At Sheboygan daytime, ozone episode concentrations were 60 ppb for ozone, 2.6 ppb for NOx, and 3.0 ppb for NOy. To facilitate informed use of the LMOS 2017 data repository, we here present comprehensive site description, including airmass influences during high ozone periods of the campaign, overview of meteorological and pollutant measurements, analysis of continuous emission monitor data from nearby large point sources, and characterization of local source impacts from vehicle traffic, large point sources, and rail. Consistent with previous field campaigns and the conceptual model of ozone episodes in the area, trajectories from the southwest, south, and lake breeze trajectories (south or southeast) were overrepresented during pollution episodes. Local source impacts from vehicle traffic, large point sources, and rail were assessed and found to represent less than about 15% of typical concentrations measured. Implications for model-observation comparison and design of future field campaigns are discussed.Implications: The Lake Michigan Ozone Study 2017 (LMOS 2017) was conducted along the western shore of Lake Michigan, and involved two well-instrumented coastal ground sites (Zion, IL, and Sheboygan, WI). LMOS 2017 data are publicly available, and this paper provides detailed site characterization and measurement summary to enable informed use of repository data. Minor local source impacts were detected but were largely confined to nighttime conditions of less interest for ozone episode analysis and modeling. The role of these sites in the wider field campaign and their detailed description facilitates future campaign planning, informed data repository use, and model-observation comparison.

Overview of the Lake Michigan Ozone Study 2017.

The Lake Michigan Ozone Study 2017 (LMOS 2017) was a collaborative multiagency field study targeting ozone chemistry, meteorology, and air quality observations in the southern Lake Michigan area. The primary objective of LMOS 2017 was to provide measurements to improve air quality modeling of the complex meteorological and chemical environment in the region. LMOS 2017 science questions included spatiotemporal assessment of nitrogen oxides (NO x = NO + NO2) and volatile organic compounds (VOC) emission sources and their influence on ozone episodes; the role of lake breezes; contribution of new remote sensing tools such as GeoTASO, Pandora, and TEMPO to air quality management; and evaluation of photochemical grid models. The observing strategy included GeoTASO on board the NASA UC-12 aircraft capturing NO2 and formaldehyde columns, an in situ profiling aircraft, two ground-based coastal enhanced monitoring locations, continuous NO2 columns from coastal Pandora instruments, and an instrumented research vessel. Local photochemical ozone production was observed on 2 June, 9-12 June, and 14-16 June, providing insights on the processes relevant to state and federal air quality management. The LMOS 2017 aircraft mapped significant spatial and temporal variation of NO2 emissions as well as polluted layers with rapid ozone formation occurring in a shallow layer near the Lake Michigan surface. Meteorological characteristics of the lake breeze were observed in detail and measurements of ozone, NOx, nitric acid, hydrogen peroxide, VOC, oxygenated VOC (OVOC), and fine particulate matter (PM2.5) composition were conducted. This article summarizes the study design, directs readers to the campaign data repository, and presents a summary of findings.

Preemptive Femoral-Femoral Crossover Grafting of Artery and Vein Before Pelvic Exenterative Surgery for Locally Advanced and Recurrent Pelvic Malignancy Involving the Aortoiliac Axis.

INTRODUCTION: Achieving a negative resection through a pelvic exenteration for a recurrent or an advanced pelvic malignancy offers the potential for cure. Exenterative surgical units have expanded the boundaries and redefined what constitutes resectable disease through improved surgical technique. In selected cases, contiguous tumor involvement of the aortoiliac axis requires en bloc resection and subsequent vessel reconstruction. However, vascular reconstruction can be challenging in a contaminated field during an extended radical resection. TECHNIQUE: The aim of this Technical Note is to describe a novel method in the management of patients with recurrent or advanced pelvic malignancy involving the aortoiliac axis by performing preemptive femoral-femoral arterial and venous crossover grafts, with adjunctive arteriovenous loop fistula formation before undergoing an extended radical pelvic resection 4 weeks later. RESULTS: Four patients have undergone preemptive femoral-femoral arterial and venous crossover grafts at our institution (median age = 60 y (range, 47-66 y); 2 women). There were no early complications, and all of the patients subsequently underwent extended radical pelvic resections for a pelvic malignancy. CONCLUSIONS: Preemptive vascular reconstruction before major pelvic surgery reduces the risk of graft infection because this method avoids the wounds being contaminated by GI or genitourinary organisms. Other advantages to this technique include a reduction in the overall operating time for the pelvic exenteration, a significant reduction in the ischemia time to the lower limbs, and ensuring that the grafts are patent before embarking on major intra-abdominal surgery.

Deep learning-based survival analysis for brain metastasis patients with the national cancer database.

PURPOSE: Prognostic indices such as the Brain Metastasis Graded Prognostic Assessment have been used in clinical settings to aid physicians and patients in determining an appropriate treatment regimen. These indices are derivative of traditional survival analysis techniques such as Cox proportional hazards (CPH) and recursive partitioning analysis (RPA). Previous studies have shown that by evaluating CPH risk with a nonlinear deep neural network, DeepSurv, patient survival can be modeled more accurately. In this work, we apply DeepSurv to a test case: breast cancer patients with brain metastases who have received stereotactic radiosurgery. METHODS: Survival times, censorship status, and 27 covariates including age, staging information, and hormone receptor status were provided for 1673 patients by the NCDB. Monte Carlo cross-validation with 50 samples of 1400 patients was used to train and validate the DeepSurv, CPH, and RPA models independently. DeepSurv was implemented with L2 regularization, batch normalization, dropout, Nesterov momentum, and learning rate decay. RPA was implemented as a random survival forest (RSF). Concordance indices of test sets of 140 patients were used for each sample to assess the generalizable predictive capacity of each model. RESULTS: Following hyperparameter tuning, DeepSurv was trained at 32 min per sample on a 1.33 GHz quad-core CPU. Test set concordance indices of 0.7488 ± 0.0049, 0.6251 ± 0.0047, and 0.7368 ± 0.0047, were found for DeepSurv, CPH, and RSF, respectively. A Tukey HSD test demonstrates a statistically significant difference between the mean concordance indices of the three models. CONCLUSION: Our results suggest that deep learning-based survival prediction can outperform traditional models, specifically in a case where an accurate prognosis is highly clinically relevant. We recommend that where appropriate data are available, deep learning-based prognostic indicators should be used to supplement classical statistics.

Demographic and Tumor Characteristic Impact on Laryngeal Cancer Outcomes in a Minority Underserved Patient Population.

OBJECTIVE: Advanced laryngeal squamous cell carcinoma remains associated with approximately 50% mortality at 5 years. Delivery of multimodality treatment remains critical to maximizing survival for this disease, but achieving this at a national level remains a difficult undertaking, particularly in under- and uninsured patients as well as minority patients. We sought to evaluate laryngeal cancer treatment delivery and clinical outcomes in a predominantly minority and underserved cohort of largely under- and uninsured patients in a county hospital. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary care county hospital in Houston, Texas. SUBJECTS AND METHODS: Patients (N = 210) with a new diagnosis of laryngeal squamous cell carcinoma treated between 2005 and 2015 were included in a retrospective analysis of patient demographics, tumor and treatment characteristics, and oncologic outcomes. RESULTS: The majority of patients presented with advanced disease (T4 = 43%, N>0 = 45%). Treatment selection was compliant with National Comprehensive Cancer Network guidelines in 81% of cases, but 76% of patients who required adjuvant radiotherapy were unable to start it within 6 weeks postsurgery. Overall survival and disease-free survival were 52% and 63% for the entire cohort, respectively. Supraglottic subsite and nodal metastases were significantly associated with decreased overall survival and disease-free survival. Race/ethnicity and insurance status were not associated with worse oncologic outcomes. CONCLUSION: Under- and uninsured patients often present with advanced laryngeal cancer. Oncologic outcomes in this cohort of patients is similar to that of other published series. Moreover, tumor characteristics rather than demographic variables drive oncologic outcomes for the predominantly minority and underserved patients seeking care in our tertiary care county hospital.

Percutaneous Axillary Artery Access in Complex Endovascular Aortic Repair.

PURPOSE: This study was designed to assess the feasibility and safety of percutaneous axillary access in complex endovascular aortic repair (EVAR) with use of a percutaneous closure device. MATERIALS AND METHODS: All patients undergoing percutaneous axillary artery access between 2012 and 2017 were included. Left percutaneous axillary access was the sole antegrade aortic approach used. Patient and intervention characteristics were documented. Mortality, procedural success, technical success, peri- and postoperative complications, and repeat interventions were examined. A total of 25 percutaneous axillary access procedures were performed in 23 patients. The mean age of the treated patients was 72.2 years, and 71% were male. Percutaneous axillary access was obtained for a variety of indications (chimney EVAR, thoracoabdominal aortic aneurysm repair, thoracic EVAR, and type B dissections). Vascular access sheath sizes ranged from 6 F to 12 F. RESULTS: The procedural success rate was 96%. Technical success of vascular closure was 100%. The perioperative access complication rate was 8%: 1 dissection of the axillary artery and 1 stenosis occurred. No hematoma, hemorrhage, or neuropathies were seen. One access-related repeat intervention had to be performed. The 30-d mortality rate was 4%. CONCLUSIONS: Direct puncture and percutaneous closure of the axillary artery for complex aortic procedures is safe and feasible.

A Binational Need Assessment to Define the Level of Endovascular Expertise Required by Vascular Surgical Trainees.

BACKGROUND: There has been a shift toward competency-based surgical education programs to improve trainee performance and achieve better patient outcomes. Endovascular procedures comprise a significant volume of vascular surgery, but the current methods for assessing the endovascular competence of vascular trainees in Australia and New Zealand are suboptimal. The objective of this study was to perform a need assessment to define the scope of endovascular expertise required by vascular surgical trainees to later aid in the development of novel surgical training assessment tools. METHODS: A modified Delphi method was used to achieve expert consensus. Fifty-three key stakeholders in vascular surgical education and training (SET) in Australia and New Zealand were invited to take part in the 2-stage survey. Experts were asked which procedures they considered to be requisite for vascular surgery trainees and at which SET level competence should be achieved. The results were reiterated to the expert panel in the second stage, and consensus considered achieved if over 75% of experts were in agreement. RESULTS: In the first stage 25 experts reached consensus that competence in 18 of the 26 procedures should be requisite for SET trainees. Twenty-two experts responded to the second stage and consensus was achieved for 12 out of 14 of the procedural items with mean percentage of experts in agreement being 90%. CONCLUSIONS: A need assessment using a modified Delphi method has achieved consensus among experts in vascular surgery regarding the endovascular procedures considered to be requisite for vascular surgery trainees in Australia and New Zealand.

Anterior lumbar interbody fusion in a lateral decubitus position: technique and outcomes in obese patients.

BACKGROUND: Multilevel lumbar interbody fusion (LIF) surgery in obese patients is problematic, with positioning and anaesthetic risks during posterior approaches, vascular and visceral complications during anterior approaches, and lack of access to L5/S1 during lateral approaches. Modified anterior LIF (ALIF) via an anterolateral retroperitoneal approach in the lateral decubitus position permits access to L3/4, L4/5, and L5/S1 levels without patient repositioning. This study reports our initial experience with this lateral ALIF in obese patients and describes modifications of existing lateral and anterior techniques. METHODS: We retrospectively analysed a prospectively maintained registry including the first 30 consecutive patients who underwent lateral ALIF. In all patients, supine ALIF was relatively contraindicated because of obesity or previous abdominal surgery. All patients had a body mass index (BMI) ≥30 kg/m2. Fusion was assessed by high-definition computed tomography. Patient-reported outcomes included visual analogue scale pain scores, Oswestry Disability Index (ODI), and 36-Item Short-Form Survey (SF-36) physical and mental component scores (PCS and MCS). All patients underwent ≥2 years follow-up. RESULTS: At last follow-up (mean, 35.0 months) mean back pain improved 64%, leg pain improved 67%, ODI improved 54%, and PCS and MCS both improved 37% (P<0.05 versus preoperative for all). Mean BMI was unchanged postoperatively (P=0.83). Complications occurred in 7 (23%) patients: dysesthesia [2], retroperitoneal hematoma [2], radiculopathy [1], and subsidence [2]. Solid interbody fusion occurred in 19 (63%) patients at 12 months postoperatively and in 26 (87%) patients at 24 months. CONCLUSIONS: Lateral ALIF enables L5/S1 anterior fusion in obese patients and permits multilevel fusion using a single position. Satisfactory clinical outcomes and complication rates are achieved despite unchanged BMI and 87% radiological fusion rates. Lateral ALIF appears to be a reasonable alternative to posterior, lateral, and supine-position anterior approaches for L3/4, L4/5, and L5/S1 interbody fusions.