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Coumans, Jean-Valery

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Coumans

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Jean-Valery

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Coumans, Jean-Valery
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Now showing 1 - 9 of 9
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    Interfacility Helicopter Ambulance Transport of Neurosurgical Patients: Observations, Utilization, and Outcomes from a Quaternary Level Care Hospital
    (Public Library of Science (PLoS), 2011) Walcott, Brian; Coumans, Jean-Valery; Mian, Matthew; Nahed, Brian; Kahle, Kristopher T.
    Background: The clinical benefit of helicopter transport over ground transportation for interfacility transport is unproven. We sought to determine actual practice patterns, utilization, and outcomes of patients undergoing interfacility transport for neurosurgical conditions. Methodology/Principal Findings: We retrospectively examined all interfacility helicopter transfers to a single trauma center during 2008. We restricted our analysis to those transfers leading either to admission to the neurosurgical service or to formal consultation upon arrival. Major exclusion criteria included transport from the scene, death during transport, and transport to any area of the hospital other than the emergency department. The primary outcome was time interval to invasive intervention. Secondary outcomes were estimated ground transportation times from the referring hospital, admitting disposition, and discharge disposition. Of 526 candidate interfacility helicopter transfers to our emergency department in 2008, we identified 167 meeting study criteria. Seventy-five (45%) of these patients underwent neurosurgical intervention. The median time to neurosurgical intervention ranged from 1.0 to 117.8 hours, varying depending on the diagnosis. For 101 (60%) of the patients, estimated driving time from the referring institution was less than one hour. Four patients (2%) expired in the emergency department, and 34 patients (20%) were admitted to a non-ICU setting. Six patients were discharged home within 24 hours. For those admitted, in-hospital mortality was 28%. Conclusions/Significance: Many patients undergoing interfacility transfer for neurosurgical evaluation are inappropriately triaged to helicopter transport, as evidenced by actual times to intervention at the accepting institution and estimated ground transportation times from the referring institution. In a time when there is growing interest in health care cost containment, practitioners must exercise discretion in the selection of patients for air ambulance transport—particularly when it may not bear influence on clinical outcome. Neurosurgical evaluation via telemedicine may be one strategy for improving air transport triage.
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    Sporadic hemangioblastomas are characterized by cryptic VHL inactivation
    (Springer Nature, 2014) Shankar, Ganesh; Taylor-Weiner, Amaro; Lelic, Nina; Jones, Robert T; Kim, James C; Francis, Joshua M; Abedalthagafi, Malak; Borges, Lawrence; Coumans, Jean-Valery; Curry, William; Nahed, Brian; Shin, John; Paek, Sun Ha; Park, Sung-Hye; Stewart, Chip; Lawrence, Michael S; Cibulskis, Kristian; Thorner, Aaron R; Van Hummelen, Paul; Stemmer-Rachamimov, Anat; Batchelor, Tracy; Carter, Scott; Hoang, Mai; Santagata, Sandro; Louis, David; Barker, Frederick; Meyerson, Matthew; Getz, Gad; Brastianos, Priscilla; Cahill, Daniel
    Hemangioblastomas consist of 10-20% neoplastic “stromal” cells within a vascular tumor cell mass of reactive pericytes, endothelium and lymphocytes. Familial cases of central nervous system hemangioblastoma uniformly result from mutations in the Von Hippel-Lindau (VHL) gene. In contrast, inactivation of VHL has been previously observed in only a minority of sporadic hemangioblastomas, suggesting an alternative genetic etiology. We performed deep-coverage DNA sequencing on 32 sporadic hemangioblastomas (whole exome discovery cohort n = 10, validation n = 22), followed by analysis of clonality, copy number alteration, and somatic mutation. We identified somatic mutation, loss of heterozygosity and/or deletion of VHL in 8 of 10 discovery cohort tumors. VHL inactivating events were ultimately detected in 78% (25/32) of cases. No other gene was significantly mutated. Overall, deep-coverage sequence analysis techniques uncovered VHL alterations within the neoplastic fraction of these tumors at higher frequencies than previously reported. Our findings support the central role of VHL inactivation in the molecular pathogenesis of both familial and sporadic hemangioblastomas.
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    Time interval to surgery and outcomes following the surgical treatment of acute traumatic subdural hematoma
    (Elsevier BV, 2014) Walcott, Brian; Khanna, Arjun; Kwon, Churl-Su; Phillips, H. Westley; Nahed, Brian; Coumans, Jean-Valery
    Although the pre-surgical management of patients with acute traumatic subdural hematoma prioritizes rapid transport to the operating room, there is conflicting evidence regarding the importance of time interval from injury to surgery with regards to outcomes. We sought to determine the association of surgical timing with outcomes for subdural hematoma. A retrospective review was performed of 522 consecutive patients admitted to a single center from 2006–2012 who underwent emergent craniectomy for acute subdural hematoma. After excluding patients with unknown time of injury, penetrating trauma, concurrent cerebrovascular injury, epidural hematoma, or intraparenchymal hemorrhage greater than 30 mL, there remained 45 patients identified for analysis. Using a multiple regression model, we examined the effect of surgical timing, in addition to other variables on in-hospital mortality (primary outcome), as well as the need for tracheostomy or gastrostomy (secondary outcome). We found that increasing injury severity score (odds ratio [OR] 1.146; 95% confidence interval [CI] 1.035–1.270; p = 0.009) and age (OR1.066; 95%CI 1.006–1.129; p = 0.031) were associated with in-hospital mortality in multivariate analysis. In this model, increasing time to surgery was not associated with mortality, and in fact had a significant effect in decreasing mortality (OR 0.984; 95%CI 0.971–0.997; p = 0.018). Premorbid aspirin use was associated with a paradoxical decrease in mortality (OR 0.019; 95%CI 0.001–0.392; p = 0.010). In this patient sample, shorter time interval from injury to surgery was not associated with better outcomes. While there are potential confounding factors, these findings support the evaluation of rigorous preoperative resuscitation as a priority in future study.
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    Trends in inpatient setting laminectomy for excision of herniated intervertebral disc: Population-based estimates from the US nationwide inpatient sample
    (Medknow, 2011) Walcott, Brian; Hanak, Brian W; Caracci, James R; Redjal, Navid; Nahed, Brian; Kahle, Kristopher T.; Coumans, Jean-Valery
    Background: Herniated intervertebral discs can result in pain and neurological compromise. Treatment for this condition is categorized as surgical or non-surgical. We sought to identify trends in inpatient surgical management of herniated intervertebral discs using a national database. Methods: Patient discharges identified with a principal procedure relating to laminectomy for excision of herniated intervertebral disc were selected from the Nationwide Inpatient Sample (Healthcare Cost and Utilization Project - Agency for Healthcare Research and Quality, Rockville, MD), under the auspices of a data user agreement. These surgical patients did not undergo instrumented fusion. To account for the Nationwide Inpatient Sample weighting schema, design-adjusted analyses were used. The estimates of standard errors were calculated using SUDAAN software (Research Triangle International, NC, USA). This software is based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM); a uniform and standardized coding system. Results: Using International Classification of Disease 9th Revision clinical modifier (ICD-9 CM) procedure code 80.51, we were able to identify disc excision, in part or whole, by laminotomy or hemilaminectomy. The incidence of laminectomy for the excision of herniated intervertebral disc has decreased dramatically from 1993 where 266,152 cases were reported [CI = 22,342]. In 2007, only 123,398 cases were identified [CI = 12,438]. The average length of stay in 1993 was 4 days [CI = 0.17], and in 2007 it decreased to just 2 days [CI = 0.17]. Both these comparisons were significantly different at P < 0.001. The average inflation adjusted (2007 buying power) charge of the procedure in 1993 was 14,790.87 USD [CI = 916.85]. This value rose in 2007 to 24,639 USD [CI = 1,485.51]. This difference was significant at P < 0.001.Conclusions: National estimates indicate that the incidence of inpatient laminectomy for the excision of herniated intervertebral disc has decreased significantly. This trend is multifactorial and is likely related to developments in outcomes research, the growing popularity of alternative procedures (intervertebral instrumented fusion), and transition to an ambulatory setting of surgical care.
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    Craniectomy for Malignant Cerebral Infarction: Prevalence and Outcomes in US Hospitals
    (Public Library of Science (PLoS), 2011) Walcott, Brian; Kuklina, Elena V.; Nahed, Brian; George, Mary G.; Kahle, Kristopher T.; Simard, J. Marc; Asaad, Wael F.; Coumans, Jean-Valery
    Object: Randomized trials have demonstrated the efficacy of craniectomy for the treatment of malignant cerebral edema following ischemic stroke. We sought to determine the prevalence and outcomes related to this by using a national database. Methods: Patient discharges with ischemic stroke as the primary diagnosis undergoing craniectomy were queried from the US Nationwide Inpatient Sample from 1999 to 2008. A subpopulation of patients was identified that underwent thrombolysis. Two primary end points were examined: in-hospital mortality and discharge to home/routine care. To facilitate interpretations, adjusted prevalence was calculated from the overall prevalence and two age-specific logistic regression models. The predictive margin was then generated using a multivariate logistic regression model to estimate the probability of in-hospital mortality after adjustment for admission type, admission source, length of stay, total hospital charges, chronic comorbidities, and medical complications. Results: After excluding 71,996 patients with the diagnosis of intracranial hemorrhage and posterior intracranial circulation occlusion, we identified 4,248,955 adult hospitalizations with ischemic stroke as a primary diagnosis. The estimated rates of hospitalizations in craniectomy per 10,000 hospitalizations with ischemic stroke increased from 3.9 in 1999–2000 to 14.46 in 2007–2008 (p for linear trend,0.001). Patients 60+ years of age had in-hospital mortality of 44% while the 18–59 year old group was found to be 24%(p = 0.14). Outcomes were comparable if recombinant tissue plasminogen activator had been administered. Conclusions: Craniectomy is being increasingly performed for malignant cerebral edema following large territory cerebral ischemia. We suspect that the increase in the annual incidence of DC for malignant cerebral edema is directly related to the expanding collection of evidence in randomized trials that the operation is efficacious when performed in the correct patient population. In hospital mortality is high for all patients undergoing this procedure.
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    Volumetric analysis of syringomyelia following hindbrain decompression for Chiari malformation Type I: syringomyelia resolution follows exponential kinetics
    (Journal of Neurosurgery Publishing Group (JNSPG), 2011) Coumans, Jean-Valery; Walcott, Brian; Butler, William; Nahed, Brian; Kahle, Kristopher T.
    Object: Resolution of syringomyelia is common following hindbrain decompression for Chiari malformation, yet little is known about the kinetics governing this process. The authors sought to establish the volumetric rate of syringomyelia resolution. Methods: A retrospective cohort of patients undergoing hindbrain decompression for a Chiari malformation Type I with preoperative cervical or thoracic syringomyelia was identified. Patients were included in the study if they had at least 3 neuroimaging studies that detailed the entirety of their preoperative syringomyelia over a minimum of 6 months postoperatively. The authors reconstructed the MR images in 3 dimensions and calculated the volume of the syringomyelia. They plotted the syringomyelia volume over time and constructed regression models using the method of least squares. The Akaike information criterion and Bayesian information criterion were used to calculate the relative goodness of fit. The coefficients of determination R2 (unadjusted and adjusted) were calculated to describe the proportion of variability in each individual data set accounted for by the statistical model. Results: Two patients were identified as meeting inclusion criteria. Plots of the least-squares best fit were identified as 4.01459e−0.0180804x and 13.2556e−0.00615859x. Decay of the syringomyelia followed an exponential model in both patients (R2 = 0.989582 and 0.948864). Conclusions: Three-dimensional analysis of syringomyelia resolution over time enables the kinetics to be estimated. This technique is yet to be validated in a large cohort. Because syringomyelia is the final common pathway for a number of different pathological processes, it is possible that this exponential only applies to syringomyelia related to treatment of Chiari malformation Type I.
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    Multimodal Therapy of an Intramedullary Cervical Primitive Neuroectodermal Tumor in an Adult
    (American Society of Clinical Oncology (ASCO), 2012) Coumans, Jean-Valery; Walcott, B. P.; Nahed, Brian; Oh, Kevin; Chi, Anthony Wei Shine
    Primitive neuroectodermal tumors (PNETs) are malignant, poorly differentiated neoplasms derived from the neural crest.1 They include cerebellar medulloblastomas but can also arise in the cerebral cortex (supratentorial PNETs), pineal region (pineoblastomas), spinal cord, cauda equina, and peripheral nerves.2 Only a few cases of primary intraspinal PNETs have been reported in children3-14 and in adults.15-17 To our knowledge, there has only been one previously reported case of intramedullary PNET of the cervical spine in an adult.17 In this article, we present a rare adult patient with a primary intramedullary cervical PNET and describe his treatment regimen and outcome.
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    Socioeconomic Status Correlates with the Prevalence of Advanced Coronary Artery Disease in the United States
    (Public Library of Science, 2012) Bashinskaya, Bronislava; Nahed, Brian; Walcott, Brian; Coumans, Jean-Valery; Onuma, Oyere Kalu
    Background: Increasingly studies have identified socioeconomic factors adversely affecting healthcare outcomes for a multitude of diseases. To date, however, there has not been a study correlating socioeconomic details from nationwide databases on the prevalence of advanced coronary artery disease. We seek to identify whether socioeconomic factors contribute to advanced coronary artery disease prevalence in the United States. Methods and Findings: State specific prevalence data was queried form the United States Nationwide Inpatient Sample for 2009. Patients undergoing percutaneous coronary angioplasty and coronary artery bypass graft were identified as principal procedures. Non-cardiac related procedures, lung lobectomy and hip replacement (partial and total) were identified and used as control groups. Information regarding prevalence was then merged with data from the Behavioral Risk Factor Surveillance System, the largest, on-going telephone health survey system tracking health conditions and risk behaviors in the United States. Pearson's correlation coefficient was calculated for individual socioeconomic variables including employment status, level of education, and household income. Household income and education level were inversely correlated with the prevalence of percutaneous coronary angioplasty (−0.717; −0.787) and coronary artery bypass graft surgery (−0.541; −0.618). This phenomenon was not seen in the non-cardiac procedure control groups. In multiple linear regression analysis, socioeconomic factors were significant predictors of coronary artery bypass graft and percutaneous transluminal coronary angioplasty (p<0.001 and p = 0.005, respectively). Conclusions: Socioeconomic status is related to the prevalence of advanced coronary artery disease as measured by the prevalence of percutaneous coronary angioplasty and coronary artery bypass graft surgery.
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    Conflict of Interest in Spine Research Reporting
    (Public Library of Science, 2012) Walcott, Brian; Sheth, Sameer Anil; Nahed, Brian; Coumans, Jean-Valery
    Background: Medical studies are more likely to report favorable findings when a conflict of interest is declared. We aim to quantify and determine the effect of author disclosure of conflict of interest on scientific reporting. Methods: Abstracts from an international spine research meeting (North American Spine Society 2010) were selected that specifically evaluated a device, biologic, or proprietary procedure. They were then made anonymous to reviewers. An item of interest was established in each of the abstracts in order to standardize evaluation. Next, three blinded reviewers independently rated the abstracts as favorable, neutral, or unfavorable with regard to the item of interest. Additionally, the blinded reviewers attempted to predict whether a related disclosure was made. The meeting disclosure index was used to tabulate the minimum US dollar value attributable to disclosures. Results: Of the 344 total abstracts, 76 met inclusion criteria. In 79%, a related conflict of interest was reported. The amount of the disclosure was incompletely reported in 30% of cases. Where available, it averaged a cumulative minimum of $219,634 USD per abstract. The results of the abstracts were judged to be favorable, neutral, and unfavorable in 63%, 32% and 5% of abstracts, respectively. There was no correlation between the presence of a related disclosure and the findings of the studies (p = 0.81), although interpretation of this is limited by a small sample size and an overall apparent bias to report favorable studies. Additionally, the blinded reviewers were unable to predict whether a related disclosure was made (p = 0.40). Conclusion: No association existed between the presence of a related disclosure and the results of the studies. While the actual compliance with reporting a potential conflict of interest is unable to be determined, the value amount related to the disclosures made was inadequately reported according to meeting guidelines.