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Find video protocols related to scientific articles indexed in Pubmed.
Prospective multicenter assessment of risk factors for rod fracture following surgery for adult spinal deformity.
J Neurosurg Spine
PUBLISHED: 10-18-2014
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Object Improved understanding of rod fracture (RF) following adult spinal deformity (ASD) surgery could prove valuable for surgical planning, patient counseling, and implant design. The objective of this study was to prospectively assess the rates of and risk factors for RF following surgery for ASD. Methods This was a prospective, multicenter, consecutive series. Inclusion criteria were ASD, age > 18 years, ?5 levels posterior instrumented fusion, baseline full-length standing spine radiographs, and either development of RF or full-length standing spine radiographs obtained at least 1 year after surgery that demonstrated lack of RF. ASD was defined as presence of at least one of the following: coronal Cobb angle ?20°, sagittal vertical axis (SVA) ?5 cm, pelvic tilt (PT) ?25°, and thoracic kyphosis ?60°. Results Of 287 patients who otherwise met inclusion criteria, 200 (70%) either demonstrated RF or had radiographic imaging obtained at a minimum of 1 year after surgery showing lack of RF. The patients' mean age was 54.8 ± 15.8 years; 81% were women; 10% were smokers; the mean body mass index (BMI) was 27.1 ± 6.5; the mean number of levels fused was 12.0 ± 3.8; and 50 patients (25%) had a pedicle subtraction osteotomy (PSO). The rod material was cobalt chromium (CC) in 53%, stainless steel (SS), in 26%, or titanium alloy (TA) in 21% of cases; the rod diameters were 5.5 mm (in 68% of cases), 6.0 mm (in 13%), or 6.35 mm (in 19%). RF occurred in 18 cases (9.0%) at a mean of 14.7 months (range 3-27 months); patients without RF had a mean follow-up of 19 months (range 12-24 months). Patients with RF were older (62.3 vs 54.1 years, p = 0.036), had greater BMI (30.6 vs 26.7, p = 0.019), had greater baseline sagittal malalignment (SVA 11.8 vs 5.0 cm, p = 0.001; PT 29.1° vs 21.9°, p = 0.016; and pelvic incidence [PI]-lumbar lordosis [LL] mismatch 29.6° vs 12.0°, p = 0.002), and had greater sagittal alignment correction following surgery (SVA reduction by 9.6 vs 2.8 cm, p < 0.001; and PI-LL mismatch reduction by 26.3° vs 10.9°, p = 0.003). RF occurred in 22.0% of patients with PSO (10 of the 11 fractures occurred adjacent to the PSO level), with rates ranging from 10.0% to 31.6% across centers. CC rods were used in 68% of PSO cases, including all with RF. Smoking, levels fused, and rod diameter did not differ significantly between patients with and without RF (p > 0.05). In cases including a PSO, the rate of RF was significantly higher with CC rods than with TA or SS rods (33% vs 0%, p = 0.010). On multivariate analysis, only PSO was associated with RF (p = 0.001, OR 5.76, 95% CI 2.01-15.8). Conclusions Rod fracture occurred in 9.0% of ASD patients and in 22.0% of PSO patients with a minimum of 1-year follow-up. With further follow-up these rates would likely be even higher. There was a substantial range in the rate of RF with PSO across centers, suggesting potential variations in technique that warrant future investigation. Due to higher rates of RF with PSO, alternative instrumentation strategies should be considered for these cases.
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TheT1 pelvic angle, a novel radiographic measure of global sagittal deformity, accounts for both spinal inclination and pelvic tilt and correlates with health-related quality of life.
J Bone Joint Surg Am
PUBLISHED: 10-03-2014
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Adult spinal deformity is a prevalent cause of pain and disability. Established measures of sagittal spinopelvic alignment such as sagittal vertical axis and pelvic tilt can be modified by postural compensation, including pelvic retroversion, knee flexion, and the use of assistive devices for standing. We introduce the T1 pelvic angle, a novel measure of sagittal alignment that simultaneously accounts for both spinal inclination and pelvic retroversion. The purpose of this study was to investigate the relationship of the T1 pelvic angle and other established sagittal alignment measures and to correlate these parameters with health-related quality-of-life measures.
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Proximal Junctional Kyphosis and Failure Following Spinal Deformity Surgery: A Systematic Review of the Literature as a Background to Classification Development.
Spine
PUBLISHED: 10-02-2014
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Study Design. Systematic review of literatureObjective. To perform a comprehensive English language systematic literature review of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF), concentrating on incidence, risk factors, HRQOL impact, prevention strategy, outcomes of revision surgery and classification systems.Summary of Background Data. PJK and PJF are well described clinical pathologies and is a frequent cause of revision surgery. The development of a PJK classification which correlates with clinical outcomes and guides treatment decisions and possible prevention strategies would be of significant benefit to patients and surgeons.Methods. The phrases "proximal junctional," "proximal junctional kyphosis," and "proximal junctional failure" were used as search terms in PubMed for all years up to 2014 to identify all articles that included at least one of these terms.Results. 53 articles were identified overall. 18 articles assessed for risk factors. 8 studies specially reviewed prevention strategies. There were no randomized prospective studies. There are 3 published studies that have attempted to classify PJK. The reported incidence of PJK ranged widely, from 5% to 46% in patients undergoing spinal instrumentation and fusion for adult spinal deformity (ASD). It is reported that 66% of PJK occurs within 3 months postoperatively, and 80% within 18 months. The reported revision rates due to PJK range from 13% to 55%. Modifiable and non-modifiable risk factors for PJK have been characterized.Conclusion. PJK and PJF affect many patients following long segment instrumentation following the correction of ASD. The epidemiology and risk factors for the disease are well defined. Preoperative risk factor scoring may help guide prevention strategy recommendations. The development and prospective validation of an SRS PJK Classification system is important considering the prevalence of the problem and its clinical and economic impact.
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Clinical correlates of infarct shape and volume in lacunar strokes: the Secondary Prevention of Small Subcortical Strokes trial.
Stroke
PUBLISHED: 09-04-2014
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Infarct size and location are thought to correlate with different mechanisms of lacunar infarcts. We examined the relationship between the size and shape of lacunar infarcts and vascular risk factors and outcomes.
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Risk of ischaemic stroke according to pattern of atrial fibrillation: analysis of 6563 aspirin-treated patients in ACTIVE-A and AVERROES.
Eur. Heart J.
PUBLISHED: 09-03-2014
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The pattern of atrial fibrillation (AF) occurrence-paroxysmal, persistent, or permanent-is associated with progressive stages of atrial dysfunction and structural changes and may therefore be associated with progressively higher stroke risk. However, previous studies have not consistently shown AF pattern to predict stroke but have been hampered by methodological shortcomings of low power, variable event ascertainment, and variable anticoagulant use.
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Predictors of mortality in patients with lacunar stroke in the secondary prevention of small subcortical strokes trial.
Stroke
PUBLISHED: 08-26-2014
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The Secondary Prevention of Small Subcortical Stroke trial (SPS3) recruited participants meeting clinical and radiological criteria for symptomatic lacunes. Individuals randomized to dual antiplatelet therapy with clopidogrel and aspirin had an unanticipated increase in all-cause mortality compared with those assigned to aspirin. We investigated the factors associated with mortality in this well-characterized population.
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Autonomous in situ measurements of seawater alkalinity.
Environ. Sci. Technol.
PUBLISHED: 08-07-2014
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Total alkalinity (AT) is an important parameter for describing the marine inorganic carbon system and understanding the effects of atmospheric CO2 on the oceans. Measurements of AT are limited, however, because of the laborious process of collecting and analyzing samples. In this work we evaluate the performance of an autonomous instrument for high temporal resolution measurements of seawater AT. The Submersible Autonomous Moored Instrument for alkalinity (SAMI-alk) uses a novel tracer monitored titration method where a colorimetric pH indicator quantifies both pH and relative volumes of sample and titrant, circumventing the need for gravimetric or volumetric measurements. The SAMI-alk performance was validated in the laboratory and in situ during two field studies. Overall in situ accuracy was -2.2 ± 13.1 ?mol kg(-1) (n = 86), on the basis of comparison to discrete samples. Precision on duplicate analyses of a carbonate standard was ±4.7 ?mol kg(-1) (n = 22). This prototype instrument can measure in situ AT hourly for one month, limited by consumption of reagent and standard solutions.
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Life Expectancy and Metastatic Spine Scoring Systems: An Academic Institutional Experience.
J Spinal Disord Tech
PUBLISHED: 08-05-2014
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A retrospective data collection study with application of metastatic spine scoring systems.
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Intraoperative neurophysiological monitoring in anterior lumbar interbody fusion surgery.
J Clin Neurophysiol
PUBLISHED: 08-02-2014
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Somatosensory evoked potential (SSEP) and motor evoked potentials (MEP) are frequently fused to monitor neurological function during spinal deformity surgery. However, there are few studies regarding the utilization of intraoperative neuromonitoring during anterior lumbar interbody fusion (ALIF). This study presents the authors' experience with intraoperative neuromonitoring in ALIF.
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Posterior fixation without debridement for vertebral body osteomyelitis and discitis.
Neurosurg Focus
PUBLISHED: 08-02-2014
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The authors evaluated the efficacy of posterior instrumentation for the management of spontaneous spinal infections. Standard surgical management of spontaneous spinal infection is based on debridement of the infected tissue. However, this can be very challenging as most of these patients are medically debilitated and the surgical debridement requires a more aggressive approach to the spine either anteriorly or via an expanded posterior approach. The authors present their results using an alternative treatment method of posterior-only neuro-decompression and stabilization without formal debridement of anterior tissue for treating spontaneous spinal infection.
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Lacunar strokes in patients with diabetes mellitus: risk factors, infarct location, and prognosis: the secondary prevention of small subcortical strokes study.
Stroke
PUBLISHED: 07-17-2014
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Diabetes mellitus is an independent risk factor for lacunar strokes. Few data are available regarding patient features, infarct location, and recurrent vascular events for patients with diabetes mellitus with lacunar stroke.
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Insecticidal properties and chemical composition of essential oils of some aromatic herbs from Morocco.
Nat. Prod. Res.
PUBLISHED: 07-15-2014
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The essential oils (EOs) of Artemisia herba alba, Rutachalepensis and Satureja calamintha aerial parts were analysed by GC/MS and the EOs were tested for their toxicity against two flour beetles, Tribolium castaneum and Tribolium confusum. EO composition showed that the major compounds were pulegone, menthone and menthol for S. calamintha, camphor and ?-thujone for A. herba alba and 2-undecanone for R. chalepensis. Contact bioassay showed that all EOs were toxic to adults of T. castaneum and T. confusum. Higher toxicity was found with the EOs from S. calamintha and R. chalepensis (LD50 of 0.09-0.13 ?L/cm(2) and LD90 of 0.17-0.29 ?L/cm(2)). In fumigant toxicity test, A. herba alba and S. calamintha EOs produced insecticidal activity with S. calamintha EO being more toxic with LD50 and LD90 values of 10.5 and 19.1 ?L/L air, respectively, for T. confusum against 7.8 and 17.4 ?L/L air, respectively, for T. castaneum.
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Surgical management of primary hyperparathyroidism in Canada.
J Otolaryngol Head Neck Surg
PUBLISHED: 07-11-2014
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Primary hyperparathyroisim is a relatively common condition, for which the standard treatment is surgical excision of one or more of the parathyroid glands. Primary hyperparathyroidism can be due to a single adenoma or multiple gland hyperplasia. In recent decades localizing imaging has improved and there has been a shift away from multiple gland exploration toward a single gland excision. There are, however, no practice guidelines regarding an optimal approach to this condition. This study shows that there is a high degree of variation in practices across Canada and a large amount of uncertainty in the approach to primary hyperparathyroidism.
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`The air that we breathe¿: assessment of laser and electrosurgical dissection devices on operating theater air quality.
J Otolaryngol Head Neck Surg
PUBLISHED: 06-11-2014
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ObjectivesTo measure changes in air quality during surgery.MethodsOperating room (OR) and hallway air quality was continuously monitored over a 3-month period. Rooftop monitoring was used to control for environmental changes and to account for the infiltration of outdoor air pollutants. Air quality measurements were correlated with operative times and electro-dissection equipment used.ResultsOR air is cooler and drier compared to the adjacent hallway. Volatile organic compounds and other gases are below indoor air exposure limit guidelines. Lasers create greater 2.5 ¿m particulate matter (PM2.5) mass concentration, and greater fine and coarse particle number than cautery or cold tissue dissection. Cautery produces more ultrafine particles (UFP) than other dissection techniques. OR air has lower particle counts than outdoor environmental air by virtue of air conditioning HEPA filtration.ConclusionCompared to the outside air, operating room air has lower particle counts. Lasers produce higher concentrations of PM2.5 mass and, fine and coarse particle number counts. Cautery produces higher concentrations of UFP number counts than other modalities and warrants consideration of the use of masks with ultrafine particle filtration capacity. Operating room air is consistently cooler with decreased humidity, which may cause airway irritation.
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Bone mineral density and donor age are not predictive of femoral ring allograft bone mechanical strength.
J. Orthop. Res.
PUBLISHED: 06-10-2014
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While metal or plastic interbody spinal fusion devices are manufactured to appropriate mechanical standards, mechanical properties of commercially prepared structural allograft bone remain relatively unassessed. Robust models predicting compressive load to failure of structural allograft bone based on easily measured variables would be useful. Three hundred twenty seven femoral rings from 34 cadaver femora were tested to failure in axial compression. Predictive variables included age, gender, bone mineral density (BMD), position along femoral shaft, maximum/minimum wall thickness, outer/inner diameter, and area. We used support vector regression and 10-fold cross-validation to develop robust nonlinear predictive models for load to failure. Model performance was measured by the root-mean-squared-deviation (RMSD) and correlation coefficients (r). A polynomial model using all variables had RMSD?=?7.92, r?=?0.84, indicating excellent performance. A model using all variables except BMD was essentially unchanged (RMSD?=?8.12, r?=?0.83). Eliminating both age and BMD produced a model with RMSD?=?8.41, r?=?0.82, again essentially unchanged. Compressive strength of structural allograft bone can be estimated using easily measured geometric parameters, without including BMD or age. As DEXA is costly and cumbersome, and setting upper age-limits for potential donors reduces the supply, our results may prove helpful to increase the quality and availability of structural allograft.
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Modification of outcomes with aspirin or apixaban in relation to female and male sex in patients with atrial fibrillation: a secondary analysis of the AVERROES study.
Stroke
PUBLISHED: 06-10-2014
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The main objective of the present analysis was to assess the effect of treatment with aspirin compared with apixaban on ischemic stroke and major bleeding in women compared with men. Female patients with atrial fibrillation are at increased stroke risk compared with male patients, and the underlying reasons for higher risk are uncertain.
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Eyelid and brow asymmetry in patients evaluated for upper lid blepharoplasty.
J Otolaryngol Head Neck Surg
PUBLISHED: 05-29-2014
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IntroductionIn evaluation for blepharoplasty, patients often desire improved cosmesis and/or correction of visual field deficits. However, patients are usually unaware of eyelid or brow asymmetry. Furthermore, the prevalence of eyelid and brow asymmetry is infrequently reported in the medical literature.PurposeTo determine the prevalence of brow and eyelid asymmetry in patients evaluated for upper lid blepharoplasty.MethodsOne hundred consecutive patients evaluated for upper lid blepharoplasty were included in the study. Standard pre-operative photographs were taken of all patients using consistent background and photographic equipment. Two of the authors (KM & AM) independently recorded the margin pupil (MPD), central eyebrow (CED), nasal eyebrow (NED) and temporal eyebrow (TED) distances. To test the inter-observer reliability, the senior author (SMT) recorded the same measurements for 10% of randomly selected patients. We calculated 95% confidence intervals to compare symmetry between the right and left sides.ResultsOne hundred patients (94 female, mean age 57.7) were included in the study. The average MPD, CED, NED and TED distances were 0.55 mm (95%CI 0.45-0.65), 1.77 mm (95%CI 1.47-2.07), 1.34 mm (95%CI 1.14-1.54), and 1.78 mm (95%CI 1.50-2.06), respectively. Ninety-three percent of patients had at least one asymmetric measurement of greater than 1 mm. Seventy-five percent of patients studied had at least one measurement greater than 2 mm while 37 percent had at least one greater than 3 mm.ConclusionBrow and eyelid asymmetry is common in patients being evaluated for upper lid blepharoplasty. The facial plastic surgeon should identify and document facial asymmetry pre-operatively, and discuss it with prospective blepharoplasty patients. This will improve informed consent and patient expectations.
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Vitamin K antagonists and risk of subdural hematoma: meta-analysis of randomized clinical trials.
Stroke
PUBLISHED: 05-13-2014
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Subdural hematomas are an important bleeding complication of anticoagulation. We quantify the risk of subdural hematoma associated with anticoagulation with vitamin K antagonists (VKAs) compared with other oral antithrombotic therapies.
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Stroke prevention in atrial fibrillation: Commentary regarding the AAN's evidence-based guideline update.
Neurol Clin Pract
PUBLISHED: 05-03-2014
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Atrial fibrillation is a common, potentially preventable cause of disabling stroke in the elderly, particularly in elderly women, resulting from embolism of stasis-precipitated thrombi formed in the left atrial appendage. In 1989, the first randomized clinical trial of anticoagulant therapy in atrial fibrillation showed that warfarin produced a large reduction in ischemic stroke.(1) In the ensuing 25 years, more than 40 additional randomized trials have permitted stroke prophylaxis to be importantly refined. It has been a period of remarkable progress in stroke prevention. Here, we discuss selected aspects of the American Academy of Neurology (AAN)'s evidence-based guideline update.(2.)
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Complications and intercenter variability of three-column osteotomies for spinal deformity surgery: a retrospective review of 423 patients.
Neurosurg Focus
PUBLISHED: 05-03-2014
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Three-column resection osteotomies (3COs) are commonly performed for sagittal deformity but have high rates of reported complications. Authors of this study aimed to examine the incidence of and intercenter variability in major intraoperative complications (IOCs), major postoperative complications (POCs) up to 6 weeks postsurgery, and overall complications (that is, both IOCs and POCs). They also aimed to investigate the incidence of and intercenter variability in blood loss during 3CO procedures.
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Surgical treatment of pathological loss of lumbar lordosis (flatback) in patients with normal sagittal vertical axis achieves similar clinical improvement as surgical treatment of elevated sagittal vertical axis: clinical article.
J Neurosurg Spine
PUBLISHED: 04-25-2014
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Increased sagittal vertical axis (SVA) correlates strongly with pain and disability for adults with spinal deformity. A subset of patients with sagittal spinopelvic malalignment (SSM) have flatback deformity (pelvic incidence-lumbar lordosis [PI-LL] mismatch > 10°) but remain sagittally compensated with normal SVA. Few data exist for SSM patients with flatback deformity and normal SVA. The authors' objective was to compare baseline disability and treatment outcomes for patients with compensated (SVA < 5 cm and PI-LL mismatch > 10°) and decompensated (SVA > 5 cm) SSM.
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Adverse events recording and reporting in clinical trials of cervical total disk replacement.
Instr Course Lect
PUBLISHED: 04-12-2014
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Adverse events reporting in pivotal trials of new technologies, such as cervical total disk replacement, are essential to determine safety. Important questions concerning the adequacy of reporting about such new technologies in peer-reviewed publications have prompted this analysis to assess the safety of cervical disk replacement compared with fusion as presented in peer-reviewed publications and FDA summary reports. Identifying differences among these reports highlight the poor quality of adverse event reporting in the peer-reviewed literature. Nine peer-reviewed studies and five FDA summary reports documented excellent safety for both cervical fusion and disk arthroplasty. No differences in rates of adverse events were found to exist between the two treatments. The methods of recording and the actual reporting of adverse events were poor in peer-reviewed manuscripts, whereas they were comprehensive but difficult to clinically apply in the FDA summaries. Recommendations to improve documentation and reporting of adverse events are presented.
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Developing a toolkit for comparing safety in spine surgery.
Instr Course Lect
PUBLISHED: 04-12-2014
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Safety information in spine surgery is important for informed patient choice and performance-based payment incentives, but measurement methods for surgical safety assessment are not standardized. Published reports of complication rates for common spinal procedures show wide variation. Factors influencing variation may include differences in safety ascertainment methods and procedure types. In a prospective cohort study, adverse events were observed in all patients undergoing spine surgery at two hospitals during a 2-year period. Multiple processes for adverse occurrence surveillance were implemented, and the associations between surveillance methods, surgery invasiveness, and observed frequencies of adverse events were examined. The study enrolled 1,723 patients. Adverse events were noted in 48.3% of the patients. Reviewers classified 25% as minor events and 23% as major events. Of the major events, the daily rounding team reported 38.4% of the events using a voluntary reporting system, surgeons reported 13.4%, and 9.1% were identified during clinical conferences. A review of medical records identified 86.7% of the major adverse events. The adverse events occurred during the inpatient hospitalization for 78.1% of the events, within 30 days for an additional 12.5%, and within the first year for the remaining 9.4%. A unit increase in the invasiveness index was associated with an 8.2% increased risk of a major adverse event. A Current Procedural Terminology-based algorithm for quantifying invasiveness correlated well with medical records-based assessment. Increased procedure invasiveness is associated with an increased risk of adverse events. The observed frequency of adverse events is influenced by the ascertainment modality. Voluntary reports by surgeons and other team members missed more than 50% of the events identified through a medical records review. Increased surgery invasiveness, measured from medical records or billing codes, is quantitatively associated with an increased risk of adverse events.
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Liposuction for Submental Lymphedema Improves Appearance and Self-Perception in the Head and Neck Cancer Patient.
Otolaryngol Head Neck Surg
PUBLISHED: 04-08-2014
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Patients who have undergone treatment for head and neck cancer are at risk for neck lymphedema, which can severely affect quality of life. Liposuction has been used successfully for cancer patients who suffer from posttreatment limb lymphedema. The purpose of our study was to review the outcomes of head and neck cancer patients at our center who have undergone submental liposuction for posttreatment lymphedema.
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Likelihood of reaching minimal clinically important difference in adult spinal deformity: a comparison of operative and nonoperative treatment.
Ochsner J
PUBLISHED: 04-02-2014
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Few studies have examined threshold improvements in health-related quality of life (HRQOL) by measuring minimal clinically important differences (MCIDs) in treatment of adult spinal deformity. We hypothesized that patients undergoing operative treatment would be more likely to achieve MCID threshold improvement compared with those receiving nonoperative care, although a subset of nonoperative patients may still reach threshold.
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Plasmodium yoelii vitamin B5 pantothenate transporter candidate is essential for parasite transmission to the mosquito.
Sci Rep
PUBLISHED: 03-27-2014
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In nearly all non-photosynthetic cells, pantothenate (vitamin B5) transport and utilization are prerequisites for the synthesis of the universal essential cofactor Coenzyme A (CoA). Early studies showed that human malaria parasites rely on the uptake of pantothenate across the parasite plasma membrane for survival within erythrocytes. Recently, a P. falciparum candidate pantothenate transporter (PAT) was characterized by functional complementation in yeast. These studies revealed that PfPAT mediated survival of yeast cells in low pantothenate concentrations and restored sensitivity of yeast cells lacking pantothenate uptake to fenpropimorph. In addition, PfPAT was refractory to deletion in P. falciparum in vitro, but nothing is known about the in vivo functions of PAT in Plasmodium life cycle stages. Herein, we used gene-targeting techniques to delete PAT in Plasmodium yoelii. Parasites lacking PAT displayed normal asexual and sexual blood stage development compared to wild-type (WT) and WT-like p230p(-) parasites. However, progression from the ookinete to the oocyst stage and sporozoite formation were completely abolished in pat(-) parasites. These studies provide the first evidence for an essential role of a candidate pantothenate transport in malaria transmission to Anopheles mosquitoes. This will set the stage for the development of PAT inhibitors against multiple parasite life cycle stages.
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Embolic strokes of undetermined source: the case for a new clinical construct.
Lancet Neurol
PUBLISHED: 03-21-2014
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Cryptogenic (of unknown cause) ischaemic strokes are now thought to comprise about 25% of all ischaemic strokes. Advances in imaging techniques and improved understanding of stroke pathophysiology have prompted a reassessment of cryptogenic stroke. There is persuasive evidence that most cryptogenic strokes are thromboembolic. The thrombus is thought to originate from any of several well established potential embolic sources, including minor-risk or covert cardiac sources, veins via paradoxical embolism, and non-occlusive atherosclerotic plaques in the aortic arch, cervical, or cerebral arteries. Accordingly, we propose that embolic strokes of undetermined source are a therapeutically relevant entity, which are defined as a non-lacunar brain infarct without proximal arterial stenosis or cardioembolic sources, with a clear indication for anticoagulation. Because emboli consist mainly of thrombus, anticoagulants are likely to reduce recurrent brain ischaemia more effectively than are antiplatelet drugs. Randomised trials testing direct-acting oral anticoagulants for secondary prevention of embolic strokes of undetermined source are warranted.
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Revision Surgery After Three-Column Osteotomy in 335 Adult Spinal Deformity Patients: Inter-Center Variability and Risk Factors.
Spine
PUBLISHED: 03-04-2014
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Study Design. Multicenter, retrospective review.Objective. Assess rates, site variability, and risk factors for revision surgery (RS) following three-column osteotomy(3CO).Summary of Background Data. Complex spinal osteotomies, including 3CO, are being increasingly performed in the setting of adult spinal deformity (ASD) patients with sagittal plane deformity. 3CO procedures are associated with high complication and RS rates, but risk factors for complications and variability across centers for revision have not been well defined.Methods. The incidence and indications for RS in 335 ASD patients were analyzed. RS indications were classified as "mechanical"(MR: implant failure, pseudarthrosis, junctional failure, loss/lack of correction) or "non-mechanical"(NMR: neurologic deficit, infection, wound dehiscence, stenosis). Risks factors for RS were analyzed using generalized linear models.Results. Three-month and one-year RS incidences were 12.3% and 17.6%, respectively. Single-level 3CO (n = 311) had lower RS rates than multi-level 3CO(n = 24, 15.8% vs. 41.7%, p = 0.001). The 16.7% rate for single-level lumbar 3CO included 11.4% for MR and 5.7% for NMR. For all RS, 50% of MR and 78.6% of NMR occurred within three-months of the index surgery. There was significant variation in rates across sites(range = 6.3% to 31.9%, p = 0.001), however low- and high-volume sites had similar rates(18.2% vs. 16.2%, p = 0.503). Patients with MR were more likely to be sagittaly under-corrected at three-months(SVA = 7cm vs 3.2cm, p = 0.003). Patients with NMR had more caudal 3CO levels (L4 vs L3, p = 0.014) and larger 3CO bone resections than patients who did not(34° vs 24.5°, p = 0.003).Conclusions. 3CO procedures for ASD surgery can provide significant deformity correction and lead to marked improvement in function despite established complication and revision rates. This study shows that RS is associated with lower level osteotomy and higher residual SVA. There is significant variability in revision rates across sites independent of site volume, suggesting potential systems and practice variations that warrant further study.
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Clinical-MRI correlations in a multiethnic cohort with recent lacunar stroke: the SPS3 trial.
Int J Stroke
PUBLISHED: 03-03-2014
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Neuroimaging manifestations of small vessel disease are heterogeneous, and correlation with patient features has not been adequately characterized.
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Genetic variation amongst biotypes of Dactylopius tomentosus.
Insect Sci.
PUBLISHED: 02-23-2014
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The tomentose cochineal scale insect, Dactylopius tomentosus (Lamarck) (Hemiptera: Dactylopiidae), is an important biological control agent against invasive species of Cylindropuntia (Caryophyllales: Cactaceae). Recent studies have demonstrated that this scale is composed of host-affiliated biotypes with differential host specificity and fitness on particular host species. We investigated genetic variation and phylogenetic relationships among D. tomentosus biotypes and provenances to examine the possibility that genetic diversity may be related to their host-use pattern, and whether their phylogenetic relationships would give insights into taxonomic relatedness of their host plants. Nucleotide sequence comparison was accomplished using sequences of the mitochondrial cytochrome c oxidase I (COI) gene. Sequences of individuals from the same host plant within a region were identical and characterized by a unique haplotype. Individuals belonging to the same biotype but from different regions had similar haplotypes. However, haplotypes were not shared between different biotypes. Phylogenetic analysis grouped the monophyletic D. tomentosus into 3 well-resolved clades of biotypes. The phylogenetic relationships and clustering of biotypes corresponded with known taxonomic relatedness of their hosts. Two biotypes, Fulgida and Mamillata, tested positive for Wolbachia (?-Proteobacteria), a common endosymbiont of insects. The Wolbachia sequences were serendipitously detected by using insect-specific COI DNA barcoding primers and are most similar to Wolbachia Supergroup F strains. This study is the first molecular characterization of cochineal biotypes that, together with Wolbachia sequences, contribute to the better identification of the biotypes of cochineal insects and to the biological control of cacti using host-specific biotypes of the scale.
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High-grade spondylolisthesis treated using a modified Bohlman technique: results among multiple surgeons.
J Neurosurg Spine
PUBLISHED: 02-21-2014
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The ideal surgical management of high-grade spondylolisthesis remains unclear. Concerns regarding the original Bohlman transsacral interbody fusion technique with stand-alone autologous fibular strut include late graft fracture and incomplete reduction of lumbosacral kyphosis. The authors' goal was to evaluate the radiographic and surgical outcomes of patients treated for high-grade spondylolisthesis with either transsacral S-1 screws or standard pedicle screw fixation augmenting the Bohlman posterior transsacral interbody fusion technique.
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CO(2) laser versus cold steel margin analysis following endoscopic excision of glottic cancer.
J Otolaryngol Head Neck Surg
PUBLISHED: 01-27-2014
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To compare the suitability of CO2 laser with steel instruments for margin excision in transoral laser microsurgery.
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A case of bilateral internal auditory canal osteomas.
Ear Nose Throat J
PUBLISHED: 01-24-2014
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Osteomas of the skull base are rare, benign, slowly progressing growths of dense cortical bone. Osteomas occurring in the internal auditory canal are extremely rare. These lesions have sometimes been linked with dizziness, sensorineural hearing loss, and/or tinnitus. Although there have been documented cases in which surgical excision has improved these symptoms, symptomatic relief is not always achieved with surgical management. Here we present, to the best of our knowledge, only the third reported case of bilateral osteomas of the internal auditory canal. An 82-year-old woman presented with an acute onset of vertigo without a history of trauma or ear infection. She reported two similar episodes occurring a few years earlier, with symptoms persisting for only a few days. Audiometry showed presbycusis. Computed tomography and magnetic resonance imaging identified bilateral internal auditory canal osteomas. The patient was treated conservatively, monitored, and had complete resolution of her symptoms.
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Long-term functional donor site morbidity of the free radial forearm flap in head and neck cancer survivors.
J Otolaryngol Head Neck Surg
PUBLISHED: 01-13-2014
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To assess the functional donor site morbidity of the forearm free flap in patients surviving at least 2 years after ablative head and neck cancer surgery in a tertiary care centre.
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ASA failure: does the combination ASA/clopidogrel confer better long-term vascular protection?
Neurology
PUBLISHED: 01-02-2014
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To assess whether adding clopidogrel to acetylsalicylic acid (ASA) has a long-term protective vascular effect in patients with lacunar stroke while taking ASA.
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Is Lower Socioeconomic Status Associated with More Advanced Thyroid Cancer Stage at Presentation? A Study in Two Canadian Centers.
Thyroid
PUBLISHED: 12-13-2013
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Background: Some studies have shown a higher incidence of thyroid cancer in patients with insurance coverage and higher socioeconomic status (SES), and a higher thyroid cancer stage in patients with lower SES, suggesting SES-related health disparity in thyroid cancer. However, it is not known if the same is evident under a universal healthcare system such as that in Canada. Methods: We used data from the Canadian Thyroid Cancer Consortium, a large thyroid cancer registry that collects data from two major thyroid cancer referral centers (London, Ontario, and Halifax, Nova Scotia). We included patients who presented with thyroid cancer between 1998 and 2011. We determined age at presentation, sex, and thyroid cancer status using the American Joint Committee on Cancer (AJCC) staging criteria. Individuals postal codes were used to retrieve data from the Canadian census for the years 1996, 2001, and 2006 to approximate household income. Ordered logistic regression was used to determine odds ratios of presenting with more advanced stage thyroid cancer as they relate to income, age, and sex. Results: We included 1701 patients: 1334 cases from London and 367 from Halifax. Thyroid cancer was diagnosed more frequently in the higher SES groups (p<0.001). Compared to patients in the top income quintile, patients in the lowest and second-lowest income quintiles had significantly higher odds of having more advanced stage thyroid cancer at presentation (OR 1.58, p=0.002; 1.37, p=0.024 respectively). Conclusions: Our study suggests that, similar to countries that lack a universal healthcare system, health disparity in thyroid cancer also exists in Canada. It appears that while thyroid cancers were diagnosed more frequently in Canadian patients of higher SES, Canadian patients in the lower SES groups had more advanced stage thyroid cancer at presentation.
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Does Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) Use in Adult Spinal Deformity (ASD) Increase Complications and Are Complications Associated With Location of rhBMP-2 Use?: A Prospective, Multicenter Study of 279 Consecutive Patients.
Spine
PUBLISHED: 11-21-2013
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Study Design. Multi-center, prospective analysis of consecutive ASD patients.Objective. Evaluate complications associated with rhBMP-2 use in ASDSummary of Background Data. Off-label rhBMP-2 use is common, however under-reporting of rhBMP-2 associated complications has been recently scrutinized.Methods. ASD patients consecutively enrolled into a prospective, multicenter database, were evaluated for type and timing of acute perioperative complications. Inclusion criteria: age ? 18 years, ASD, spinal arthrodesis >4 levels, and ?3 months follow-up. Patients divided into those receiving rhBMP-2 (BMP) or no rhBMP-2 (NOBMP). BMP divided into location of use: posterior (PBMP), interbody (IBMP), and interbody + posterior spine (I+PBMP). Correlations between acute perioperative complications and rhBMP-2 use including total dose, dose/level and location of use were evaluated.Results. 279 patients (mean age 57 years, mean spinal levels fused 12.0, mean follow-up 28.8 months) met inclusion criteria. BMP (n = 172; average posterior dose = 2.5 mg/level, average interbody dose = 5 mg/level) had similar age, smoking history, previous spine surgery, total spinal levels fused, estimated blood loss, and duration of hospital stay as NOBMP (n = 107; p>0.05). BMP had greater Charlson Comorbidity Index (1.9 vs. 1.2), greater scoliosis (43° vs. 38°), longer operative time (488.2 vs. 414.6 minutes), more osteotomies/patient (4.0 vs. 1.6) and greater percentage of anteroposterior fusion (APSF; 20.9% vs. 8.4%) than NOBMP, respectively (p<0.05). BMP had more total complications/patient (1.4 vs.0.6) and more minor complications/patient (0.9 vs. 0.2) than NOBMP, respectively (p<0.05). NOBMP had more complications requiring surgery/patient than BMP (0.3 vs. 0.2; p<0.05). Major, neurological, wound, and infection complications were similar for NOBMP, BMP, PBMP, IBMP, and I+PBMP (p>0.05). Multivariate analysis demonstrated small to non-existent correlations between rhBMP-2 use and complications.Conclusions. RhBMP-2 use and location of rhBMP-2 use in ASD surgery, at reported doses, does not increase acute major, neurological or wound complications. Research is needed for higher rhBMP-2 dosing and long-term follow-up.
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Between red and yellow: evidence of intermediates in a vapochromic Pt(II) salt.
Chem. Commun. (Camb.)
PUBLISHED: 08-29-2013
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[Pt(tpy)Cl]ClO4·H2O (1·H2O) changes from red to yellow upon dehydration due to increased Pt···Pt distances. Spectroscopic, diffraction, gravimetric and calorimetric data demonstrate the presence of intermediates during hydration and dehydration which signifies surprising mechanistic complexity in the vapochromic response.
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Reoperation rates and impact on outcome in a large, prospective, multicenter, adult spinal deformity database: clinical article.
J Neurosurg Spine
PUBLISHED: 08-23-2013
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Complications and reoperation for surgery to correct adult spinal deformity are not infrequent, and many studies have analyzed the rates and factors that influence the likelihood of reoperation. However, there is a need for more comprehensive analyses of reoperation in adult spinal deformity surgery from a global standpoint, particularly focusing on the 1st year following operation and considering radiographic parameters and the effects of reoperation on health-related quality of life (HRQOL). This study attempts to determine the prevalence of reoperation following surgery for adult spinal deformity, assess the indications for these reoperations, evaluate for a relation between specific radiographic parameters and the need for reoperation, and determine the potential impact of reoperation on HRQOL measures.
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A standardized nomenclature for cervical spine soft-tissue release and osteotomy for deformity correction: clinical article.
J Neurosurg Spine
PUBLISHED: 07-05-2013
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Cervical spine osteotomies are powerful techniques to correct rigid cervical spine deformity. Many variations exist, however, and there is no current standardized system with which to describe and classify cervical osteotomies. This complicates the ability to compare outcomes across procedures and studies. The authors objective was to establish a universal nomenclature for cervical spine osteotomies to provide a common language among spine surgeons.
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Identification of Decision Criteria for Revision Surgery among Patients with Proximal Junctional Failure following Surgical Treatment for Spinal Deformity.
Spine
PUBLISHED: 06-20-2013
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Study Design: Multi-center, retrospective, consecutive case series.Objective: This study aims to identify demographic and radiographic characteristics that influence the decision to perform revision surgery among patients with Proximal Junctional Failure (PJF).Summary of Background Data: Revision rates following PJF remain relatively high, yet the decision criteria for performing revision surgeries is not uniform and varies by surgeon. A better understanding of the factors that impact the decision to perform revision surgery is important in order to improve efficiency of surgical treatment for adult spinal deformity (ASD).Methods: A cohort of 57 PJF patients was identified retrospectively from 1,218 consecutive ASD patients. PJF was identified based on 10° post-operative increase in kyphosis between upper instrumented vertebra (UIV) and UIV+2, along with one or more of the following: fracture of the vertebral body of UIV or UIV +1, posterior osseo-ligamentous disruption, or pull-out of instrumentation at the UIV. Univariate statistical analysis was performed using t-tests and Fishers exact tests. Multivariate analysis was performed using logistic regression.Results: Twenty-seven (47.4%) patients underwent revision surgery within 6 months of the index operation. Regression results revealed that patients with combined posterior/anterior approaches at index were significantly more likely to undergo revision (p = 0.001) as were patients with more extreme PJK angulation (p = 0.034). Patients sustaining trauma were also significantly more likely to undergo revision (p = 0.019). Variables approaching but not reaching significance as predictors of revision included female gender (p = 0.066) and higher SVA (p = 0.090).Conclusions: The decision to perform revision surgery is complicated and varies by surgeon. Factors that appear to influence this decision include traumatic etiology of PJF, severity of PJK angulation, higher SVA, and female gender. Factors that were expected to influence revision but had no statistical effect included soft-tissue versus bony mode of failure, age, levels fused, and upper thoracic versus thoracolumbar proximal junction.
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Change in Classification Grade by the SRS-Schwab Adult Spinal Deformity Classification Predicts Impact on Health-Related Quality of Life Measures: Prospective Analysis of Operative and Non-operative Treatment.
Spine
PUBLISHED: 06-14-2013
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Study Design. Multicenter, prospective, consecutive series.Objective. Evaluate responsiveness of the SRS-Schwab adult spinal deformity (ASD) classification to changes in health-related quality of life (HRQOL) following treatment for ASD.Summary of Background Data. Ideally, a classification system should describe and be responsive to changes in a disease state. We hypothesized that the SRS-Schwab classification is responsive to changes in HRQOL measures following treatment for ASD.Methods. Multicenter, prospective, consecutive series from the International Spine Study Group (ISSG). Inclusion criteria: ASD, age>18, operative or non-operative treatment, baseline and one-year x-rays and HRQOL measures (Oswestry Disability Index [ODI], SRS-22, SF-36). The SRS-Schwab classification includes a curve descriptor and three sagittal spinopelvic modifiers (sagittal vertical axis [SVA], pelvic tilt [PT], pelvic incidence/lumbar lordosis mismatch [PI-LL]). Changes in modifiers at one year were assessed for impact on HRQOL from pre-treatment values based on minimal clinically important differences (MCID).Results. 341 patients met criteria (mean age = 54; 85% women; 177 operative and 164 non-operative). Change in PT modifier at one year follow-up was associated with changes in ODI and SRS-22 (total and appearance scores) (p?0.034). Change in SVA modifier at one year was associated with changes in ODI, SF-36 PCS and SRS-22 (total, activity and appearance scores) (p?0.037). Change in PI-LL modifier at one year was associated with changes in SF-36 PCS and SRS-22 (total, activity and appearance scores) (p?0.03). Patients with improvement of PT, SVA, or PI-LL modifiers were significantly more likely to achieve MCID for ODI, SF-36 PCS (SVA and PI-LL only), SRS activity, and SRS pain (PI-LL only).Conclusions. The SRS-Schwab classification provides a validated system to evaluate ASD, and the classification components correlate with HRQOL measures. The current study demonstrates that the classification modifiers are responsive to changes in disease state and reflect significant changes in patient-reported outcomes.
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The SRS-Schwab adult spinal deformity classification: assessment and clinical correlations based on a prospective operative and nonoperative cohort.
Neurosurgery
PUBLISHED: 06-13-2013
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The SRS-Schwab classification of adult spinal deformity (ASD) is a validated system that provides a common language for the complex pathology of ASD. Classification reliability has been reported; however, correlation with treatment has not been assessed.
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The Relationship between Marital Status and Psychological Resilience in Chronic Pain.
Pain Res Treat
PUBLISHED: 06-05-2013
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We examined the relationship between marital status and a 2-stage model of pain-related effect, consisting of pain unpleasantness and suffering. We studied 1914 chronic pain patients using multivariate analysis of covariance (MANCOVA) to clarify whether marital status was a determinant factor in the emotional or ideational suffering associated with chronic pain after controlling for pain sensation intensity, age, and ethnicity. Marital status was unrelated to immediate unpleasantness (P = 0.08). We found a strong association with emotional suffering (P < 0.0001) but not with negative illness beliefs (P = 0.44). Interestingly, widowed subjects experienced significantly less frustration, fear, and anger than all other groups (married, divorced, separated, or single). A final MANCOVA including sex as a covariate revealed that the emotional response to pain was the same for both widow and widower. Only those individuals whose spouse died experienced less emotional turmoil in the face of a condition threatening their lifestyle. These data suggest that after experiencing the death of a spouse, an individual may derive some "emotional inoculation" against future lifestyle threat.
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Effect of addition of clopidogrel to aspirin on stroke incidence: Meta-analysis of randomized trials.
Int J Stroke
PUBLISHED: 05-23-2013
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It remains controversial whether dual antiplatelet therapy reduces stroke more than aspirin alone.
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Can temperate insects take the heat? A case study of the physiological and behavioural responses in a common ant, Iridomyrmex purpureus (Formicidae), with potential climate change.
J. Insect Physiol.
PUBLISHED: 04-06-2013
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Insects in temperate regions are predicted to be at low risk of climate change relative to tropical species. However, these assumptions have generally been poorly examined in all regions, and such forecasting fails to account for microclimatic variation and behavioural optimisation. Here, we test how a population of the dominant ant species, Iridomyrmex purpureus, from temperate Australia responds to thermal stress. We show that ants regularly forage for short periods (minutes) at soil temperatures well above their upper thermal limits (upper lethal temperature = 45.8 ± 1.3°C; CT(max) = 46.1°C) determined over slightly longer periods (hours) and do not show any signs of a classic thermal performance curve in voluntary locomotion across soil surface temperatures of 18.6-57°C (equating to a body temperature of 24.5-43.1°C). Although ants were present all year round, and dynamically altered several aspects of their thermal biology to cope with low temperatures and seasonal variation, temperature-dependence of running speed remained invariant and ants were unable to elevate high temperature tolerance using plastic responses. Measurements of microclimate temperature were higher than ant body temperatures during the hottest part of the day, but exhibited a stronger relationship with each other than air temperatures from the closest weather station. Generally close associations of ant activity and performance with microclimatic conditions, possibly to maximise foraging times, suggest I. purpureus displays highly opportunistic thermal responses and readily adjusts behaviour to cope with high trail temperatures. Increasing frequency or duration of high temperatures is therefore likely to result in an immediate reduction in foraging efficiency. In summary, these results suggest that (1) soil-dwelling temperate insect populations may be at higher risks of thermal stress with increased frequency or duration of high temperatures resulting from climate change than previously thought, however, behavioural cues may be able to compensate to some extent; and (2) indices of climate change-related thermal stress, warming tolerance and thermal safety margin, are strongly influenced by the scale of climate metrics employed.
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Predictors of Stroke Recurrence in Patients with Recent Lacunar Stroke and Response to Interventions According to Risk Status: Secondary Prevention of Small Subcortical Strokes Trial.
J Stroke Cerebrovasc Dis
PUBLISHED: 04-01-2013
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Among participants in the Secondary Prevention of Small Subcortical Strokes randomized trial, we sought to identify patients with high versus low rates of recurrent ischemic stroke and to assess effects of aggressive blood pressure control and dual antiplatelet therapy according to risk status.
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Assessment of anticoagulation intensity and management of bleeding with old and new oral anticoagulants.
Can J Cardiol
PUBLISHED: 03-26-2013
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Warfarin is effective for the prevention and treatment of thromboembolism but produces variable anticoagulant effects and requires routine monitoring of the international normalized ratio (INR) to optimize the balance between efficacy and safety. The new oral anticoagulants (NOACs) have a more predictable anticoagulant effect and were recently demonstrated to be at least as efficacious and safe as warfarin despite being administered in fixed doses without routine coagulation monitoring. Specific laboratory tests have been developed to measure the anticoagulant effect of the NOACs but are not yet widely available, and the relation between drug levels and both coagulation test results and outcomes is uncertain. It remains to be demonstrated whether adjustment of the dose of NOACs, according to the results of laboratory testing, may lead to even greater efficacy and safety. The principles of bleeding management in patients treated with NOACs compared with patients receiving warfarin are similar. Most patients can be safely managed by interrupting drug treatment, performing local measures to stem the bleeding, and providing transfusion support as required. In patients with major or life-threatening bleeding and those requiring surgery, the anticoagulant effects of warfarin can be reversed using oral or intravenous vitamin K, fresh frozen plasma (FFP), and prothrombin complex concentrates (PCCs). Specific antidotes are under development for the NOACs but are not yet approved for clinical use. PCCs and recombinant factor VIIa may improve hemostasis in patients in whom bleeding develops during treatment with a NOAC, but their efficacy is unproven.
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Stroke prevention in atrial fibrillation patients with chronic kidney disease.
Can J Cardiol
PUBLISHED: 03-19-2013
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Chronic kidney disease (CKD) is prevalent in elderly patients with atrial fibrillation and is an independent risk factor for stroke. Warfarin anticoagulation is efficacious for stroke prevention in atrial fibrillation patients with moderate CKD (stage III, estimated glomerular filtration rate 30-59 mL/min), but recent observational studies have challenged its value for patients with end-stage renal disease requiring dialysis. The novel oral anticoagulants (i.e., dabigatran, apixaban, rivaroxaban) all undergo renal metabolism to varying degrees, and hence dosing, efficacy, and safety require special consideration in CKD patients. In randomized trials to date involving 11,169 patients with moderate CKD, the novel oral anticoagulants performed well, with similar efficacy and safety profiles as for non-CKD patients. For atrial fibrillation patients with stage III CKD, the available data are strongest for dabigatran 150 mg twice daily as superior to warfarin for stroke prevention and for apixaban as superior to warfarin regarding reduced major hemorrhage. Renal function should be monitored at least annually in patients receiving a novel oral anticoagulant, and more often in elderly patients and those with underlying CKD or comorbidities who are at special risk for dehydration and deterioration of renal function. Much remains to be learned about the optimal use of the novel oral anticoagulants in CKD patients; additional studies about optimal dosing of the novel oral anticoagulants and frequency of monitoring renal function in CKD patients with atrial fibrillation are needed. Anticoagulation options for hemodialysis patients require testing in randomized trials.
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Efficacy and safety of warfarin vs. antiplatelet therapy in patients with systolic heart failure and sinus rhythm: a systematic review and meta-analysis of randomized controlled trials.
Int J Stroke
PUBLISHED: 03-19-2013
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Heart failure is an independent risk factor for stroke. Anticoagulation is effective for prevention of cardio-embolic stroke secondary to atrial fibrillation or mechanical heart valves but is of uncertain benefit in heart failure patients. We performed this meta-analysis to obtain the best estimates of the efficacy and safety of warfarin as compared with antiplatelet therapy in patients with systolic heart failure who are in sinus rhythm.
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Illness Apprehension, Depression, Anxiety, and Quality of Life in Liver Transplant Candidates: Implications for Psychosocial Interventions.
Psychosomatics
PUBLISHED: 03-12-2013
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End-stage liver disease is associated with diminished quality of life (QOL). Numerous physical and psychosocial problems that affect QOL are common in those undergoing evaluation for liver transplantation.
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Management of high-grade spondylolisthesis.
Neurosurg. Clin. N. Am.
PUBLISHED: 02-21-2013
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Management of high-grade spondylolisthesis (HGS) remains challenging and is associated with significant controversies. The best surgical procedure remains debatable. Although the need for instrumentation is generally agreed upon, significant controversies still surround the role of reduction and anterior column support in the surgical management of HGS. Complications with operative management of HGS can be significant and often dictate the selection of surgical approach. This review highlights the pathophysiology, classification, clinical presentation, and management controversies of HGS, in light of recent advances in our understanding of the importance of sagittal spinopelvic alignment and technologic advancements.
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Proximal junctional kyphosis and proximal junctional failure.
Neurosurg. Clin. N. Am.
PUBLISHED: 02-21-2013
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Proximal junctional failure (PJF) should be distinguished from proximal junctional kyphosis, which is a recurrent deformity with limited clinical impact. PJF includes mechanical failure, and is a significant complication following adult spinal deformity surgery with potential for neurologic injury and increased need for surgical revision. Risk factors for PJF include age, severity of sagittal plane deformity, and extent of operative sagittal plane realignment. Techniques for avoiding PJF will likely require refinements in both perioperative and surgical strategies.
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Rationale and design of the Clarification of Optimal Anticoagulation through Genetics trial.
Am. Heart J.
PUBLISHED: 02-06-2013
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Current dosing practices for warfarin are empiric and result in the need for frequent dose changes as the international normalized ratio gets too high or too low. As a result, patients are put at increased risk for thromboembolism, bleeding, and premature discontinuation of anticoagulation therapy. Prior research has identified clinical and genetic factors that can alter warfarin dose requirements, but few randomized clinical trials have examined the utility of using clinical and genetic information to improve anticoagulation control or clinical outcomes among a large, diverse group of patients initiating warfarin.
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Modification of outcomes with aspirin or apixaban in relation to CHADS(2) and CHA(2)DS(2)-VASc scores in patients with atrial fibrillation: a secondary analysis of the AVERROES study.
Circ Arrhythm Electrophysiol
PUBLISHED: 02-06-2013
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The impact of apixaban versus aspirin on ischemic stroke and major bleeding in relation to the CHADS(2) and CHA(2)DS(2)-VASc stroke risk scores in atrial fibrillation has not been investigated.
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Title: Postoperative Prevertebral Soft Tissue Swelling Does Not Affect the Development of Chronic Dysphagia Following Anterior Cervical Spine Surgery.
Spine
PUBLISHED: 02-06-2013
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Study Design. Prospective cohort studyObjective. To characterize the relation between postoperative soft tissue swelling and the development of chronic dysphagia after anterior cervical spine surgery. Chronic dysphagia was defined as dysphagia that persists greater than one year.Summary of Background Data. Dysphagia is commonly reported in the early postoperative period following anterior cervical spine surgery. Although prevertebral soft tissue swelling (STS) has been hypothesized as a potential risk factor for development dysphagia, no studies have assessed STS relation to dysphagia that persists greater than one year.Methods. Sixty-seven patients who underwent elective anterior cervical spine surgery from 2008-2011 and completed a dysphagia questionnaire were included in the study. Prevertebral soft tissue swelling was measured at the caudal endplates of C2 and C6 on plain lateral cervical radiographs preoperatively, immediate, six and 12 weeks postoperatively. The presence and severity of chronic dysphagia was assessed using the Bazaz-Yoo Dysphagia Score. The prevalence of dysphagia in relation to soft tissue swelling was evaluated using the Wilcoxon Rank-Sum Test.Results. By six weeks after surgery, 89% of STS at C2 and 97% of STS at C6 had resolved, as compared to preoperative values. The overall dysphagia prevalence in our cohort was 73%, with 48% reporting no or mild symptoms. Moderate symptoms were present in 39% and severe symptoms were present in 13% of the patients. There was no relation between STS measured at all time points compared to the development of chronic dysphagia. Dysphagia did trend towards significance with higher cervical fusions (C4 and above) and as the number of levels fused increased, but STS did not appear to influence this.Conclusions. Postoperative soft tissue swelling is a self-limiting process. The magnitude of soft tissue swelling during the postoperative period does not appear to influence the development of chronic dysphagia.
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Lumbar Stiffness Disability Index: pilot testing of consistency, reliability, and validity.
Spine J
PUBLISHED: 01-19-2013
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The primary goal of surgical arthrodesis is to eliminate the motion of spinal segments in an effort to alleviate pain, improve deformity, and reduce disability. However, decreased spinal mobility may impair performance of activities of daily living (ADLs) due to the resulting stiffness or the lack of mobility of the fused segment. Current clinical outcome instruments do not seek information regarding the impact of spinal stiffness on functional ability. Therefore, a patient-reported outcome questionnaire measuring the impact of lumbar stiffness on functional abilities was devised and assessed for internal consistency, retest repeatability, and external validity.
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Aspirin therapy and risk of subdural hematoma: meta-analysis of randomized clinical trials.
J Stroke Cerebrovasc Dis
PUBLISHED: 01-14-2013
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Subdural hematomas are an important bleeding complication of antithrombotic therapies. We sought to characterize the risk of subdural hematoma associated with antiplatelet therapy.
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Balancing the benefits and risks of 2 doses of dabigatran compared with warfarin in atrial fibrillation.
J. Am. Coll. Cardiol.
PUBLISHED: 01-10-2013
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This study sought to compare the net clinical benefit of dabigatran 110 mg bid and 150 mg bid with that of warfarin in patients with atrial fibrillation (AF).
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A Portable Analyzer for Pouch-Actuated, Immunoassay Cassettes.
Sens Actuators B Chem
PUBLISHED: 11-30-2011
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A portable, small footprint, light, general purpose analyzer (processor) to control the flow in immunoassay cassettes and to facilitate the detection of test results is described. The durable analyzer accepts disposable cassettes that contain pouches and reaction chambers for various unit operations such as hydration of dry reagents, stirring, and incubation. The analyzer includes individually controlled, linear actuators to compress the pouches in the cassette, which facilitates the pumping and mixing of sample and reagents, and to close diaphragm-based valves for flow control. The same types of actuators are used to compress pouches and actuate valves. The analyzer also houses a compact OEM scanner/reader to excite fluorescence and detect emission from labels. The analyzer is hydraulically isolated from the cassette, reducing the possibility of cross-contamination. The analyzer facilitates programmable, automated execution of a sequence of operations such as pumping and valving in a timely fashion, reducing the level of expertise required from the operator and the possibility for errors. The analyzers design is modular and expandable to accommodate cassettes of various complexities and additional functionalities. In this paper, the utility of the analyzer has been demonstrated with the execution of a simple, consecutive, lateral flow assay of a model biological system and the test results were detected with up converting phosphor labels that are excited at infrared frequencies and emit in the visible spectrum.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.