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Dive into the research topics where Jean-Valery Coumans is active.

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Featured researches published by Jean-Valery Coumans.


The New England Journal of Medicine | 2016

Laminectomy plus Fusion versus Laminectomy Alone for Lumbar Spondylolisthesis.

Zoher Ghogawala; James Dziura; William E. Butler; Feng Dai; Norma Terrin; Subu N. Magge; Jean-Valery Coumans; J. Fred Harrington; Sepideh Amin-Hanjani; J. Sanford Schwartz; Volker K H Sonntag; Fred G. Barker; Edward C. Benzel

BACKGROUND The comparative effectiveness of performing instrumented (rigid pedicle screws affixed to titanium alloy rods) lumbar spinal fusion in addition to decompressive laminectomy in patients with symptomatic lumbar grade I degenerative spondylolisthesis with spinal stenosis is unknown. METHODS In this randomized, controlled trial, we assigned patients, 50 to 80 years of age, who had stable degenerative spondylolisthesis (degree of spondylolisthesis, 3 to 14 mm) and symptomatic lumbar spinal stenosis to undergo either decompressive laminectomy alone (decompression-alone group) or laminectomy with posterolateral instrumented fusion (fusion group). The primary outcome measure was the change in the physical-component summary score of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36; range, 0 to 100, with higher scores indicating better quality of life) 2 years after surgery. The secondary outcome measure was the score on the Oswestry Disability Index (range, 0 to 100, with higher scores indicating more disability related to back pain). Patients were followed for 4 years. RESULTS A total of 66 patients (mean age, 67 years; 80% women) underwent randomization. The rate of follow-up was 89% at 1 year, 86% at 2 years, and 68% at 4 years. The fusion group had a greater increase in SF-36 physical-component summary scores at 2 years after surgery than did the decompression-alone group (15.2 vs. 9.5, for a difference of 5.7; 95% confidence interval, 0.1 to 11.3; P=0.046). The increases in the SF-36 physical-component summary scores in the fusion group remained greater than those in the decompression-alone group at 3 years and at 4 years (P=0.02 for both years). With respect to reductions in disability related to back pain, the changes in the Oswestry Disability Index scores at 2 years after surgery did not differ significantly between the study groups (-17.9 in the decompression-alone group and -26.3 in the fusion group, P=0.06). More blood loss and longer hospital stays occurred in the fusion group than in the decompression-alone group (P<0.001 for both comparisons). The cumulative rate of reoperation was 14% in the fusion group and 34% in the decompression-alone group (P=0.05). CONCLUSIONS Among patients with degenerative grade I spondylolisthesis, the addition of lumbar spinal fusion to laminectomy was associated with slightly greater but clinically meaningful improvement in overall physical health-related quality of life than laminectomy alone. (Funded by the Jean and David Wallace Foundation and others; SLIP ClinicalTrials.gov number, NCT00109213.).


Neurosurgery | 2007

Cervical radiculopathy: pathophysiology, presentation, and clinical evaluation.

Khalid M. Abbed; Jean-Valery Coumans

CERVICAL RADICULOPATHY IS a common condition that usually results from compression and inflammation of the cervical nerve root or roots in the region of the neural foramen. It is frequently caused by cervical disc herniation and cervical spondylosis. The diagnosis can be established by history and physical examination, but care should be taken, as diagnoses can mimic or coexist with cervical radiculopathy, such as entrapment neuropathies. The pathophysiology, presentation, and clinical evaluation of cervical radiculopathy are discussed.


Journal of Neurosurgery | 2013

Predictors of cranioplasty complications in stroke and trauma patients

Brian P. Walcott; Churl-Su Kwon; Sameer A. Sheth; Corey R. Fehnel; Robert M. Koffie; Wael F. Asaad; Brian V. Nahed; Jean-Valery Coumans

OBJECT Decompressive craniectomy mandates subsequent cranioplasty. Complications of cranioplasty may be independent of the initial craniectomy, or they may be contingent upon the craniectomy. Authors of this study aimed to identify surgery- and patient-specific risk factors related to the development of surgical site infection and other complications following cranioplasty. METHODS A consecutive cohort of patients of all ages and both sexes who had undergone cranioplasty following craniectomy for stroke or trauma at a single institution in the period from May 2004 to May 2012 was retrospectively established. Patients who had undergone craniectomy for infectious lesions or neoplasia were excluded. A logistic regression analysis was performed to model and predict determinants related to infection following cranioplasty. RESULTS Two hundred thirty-nine patients met the study criteria. The overall rate of complication following cranioplasty was 23.85% (57 patients). Complications included, predominantly, surgical site infection, hydrocephalus, and new-onset seizures. Logistic regression analysis identified previous reoperation (OR 3.25, 95% CI 1.30-8.11, p = 0.01) and therapeutic indication for stroke (OR 2.45, 95% CI 1.11-5.39, p = 0.03) as significantly associated with the development of cranioplasty infection. Patient age, location of cranioplasty, presence of an intracranial device, bone flap preservation method, cranioplasty material, booking method, and time interval > 90 days between initial craniectomy and cranioplasty were not predictive of the development of cranioplasty infection. CONCLUSIONS Cranioplasty complications are common. Cranioplasty infection rates are predicted by reoperation following craniectomy and therapeutic indication (stroke). These variables may be associated with patient-centered risk factors that increase cranioplasty infection risk.


Neurosurgery | 2011

Comparative Effectiveness of Ventral vs Dorsal Surgery for Cervical Spondylotic Myelopathy

Zoher Ghogawala; Brook I. Martin; Edward C. Benzel; James Dziura; Subu N. Magge; Khalid M. Abbed; Erica F. Bisson; Javed Shahid; Jean-Valery Coumans; Tanvir Choudhri; Michael P. Steinmetz; Ajit A. Krishnaney; Joseph T. King; William E. Butler; Fred G. Barker; Robert F. Heary

BACKGROUND:Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction. OBJECTIVE:To determine the feasibility of a randomized clinical trial comparing the clinical effectiveness and costs of ventral vs dorsal decompression with fusion surgery for treating CSM. METHODS:A nonrandomized, prospective, clinical pilot trial was conducted. Patients ages 40 to 85 years with degenerative CSM were enrolled at 7 sites over 2 years (2007-2009). Outcome assessments were obtained preoperatively and at 3 months, 6 months, and 1 year postoperatively. A hospital-based economic analysis used costs derived from hospital charges and Medicare cost-to-charge ratios. RESULTS:The pilot study enrolled 50 patients. Twenty-eight were treated with ventral fusion surgery and 22 with dorsal fusion surgery. The average age was 61.6 years. Baseline demographics and health-related quality of life (HR-QOL) scores were comparable between groups; however, dorsal surgery patients had significantly more severe myelopathy (P < .01). Comprehensive 1-year follow-up was obtained in 46 of 50 patients (92%). Greater HR-QOL improvement (Short-Form 36 Physical Component Summary) was observed after ventral surgery (P = .05). The complication rate (16.6% overall) was comparable between groups. Significant improvement in the modified Japanese Orthopedic Association scale score was observed in both groups (P < .01). Dorsal fusion surgery had significantly greater mean hospital costs (


Journal of Neurosurgery | 2013

Radiographic predictors of delayed instability following decompression without fusion for degenerative Grade I lumbar spondylolisthesis

Claire Blumenthal; Jill Curran; Edward C. Benzel; Rachel Potter; Subu N. Magge; J. Frederick Harrington; Jean-Valery Coumans; Zoher Ghogawala

29 465 vs


PLOS ONE | 2011

Craniectomy for Malignant Cerebral Infarction: Prevalence and Outcomes in US Hospitals

Brian P. Walcott; Elena V. Kuklina; Brian V. Nahed; Mary G. George; Kristopher T. Kahle; J. Marc Simard; Wael F. Asaad; Jean-Valery Coumans

19 245; P < .01) and longer average length of hospital stay (4.0 vs 2.6 days; P < .01) compared with ventral fusion surgery. CONCLUSION:Surgery for treating CSM was followed by significant improvement in disease-specific symptoms and in HR-QOL. Greater improvement in HR-QOL was observed after ventral surgery. Dorsal fusion surgery was associated with longer length of hospital stay and higher hospital costs. The pilot study demonstrated feasibility for a larger randomized clinical trial.


PLOS ONE | 2011

Interfacility Helicopter Ambulance Transport of Neurosurgical Patients: Observations, Utilization, and Outcomes from a Quaternary Level Care Hospital

Brian P. Walcott; Jean-Valery Coumans; Matthew K. Mian; Brian V. Nahed; Kristopher T. Kahle

OBJECT It is not known whether adding fusion to lumbar decompression is necessary for all patients undergoing surgery for degenerative lumbar spondylolisthesis with symptomatic stenosis. Determining specific radiographic traits that might predict delayed instability following decompression surgery might guide clinical decision making regarding the utility of up-front fusion in patients with degenerative Grade I spondylolisthesis. METHODS Patients with Grade I degenerative lumbar spondylolisthesis (3-14 mm) with symptomatic stenosis were prospectively enrolled from a single site between May 2002 and September 2009 and treated with decompressive laminectomy without fusion. Patients with mechanical back pain or with gross motion (> 3 mm) on flexion-extension lumbar radiographs were excluded. The baseline radiographic variables measured included amount of slippage, disc height, facet angle, motion at spondylolisthesis (flexion-extension), and sagittal rotation angle. Data were analyzed using multivariate forward selection stepwise logistic regression, chi-square tests, Student t-test, and ANOVA. RESULTS Forty patients were enrolled and treated with laminectomy without fusion, and all patients had complete radiographic data sets that were available for analysis. Reoperation was performed in 15 (37.5%) of 40 patients, with a mean follow-up duration of 3.6 years. Reoperation was performed for pain caused by instability at the index level in all 15 cases. Using multivariate stepwise logistic regression with a threshold p value of 0.35, motion at spondylolisthesis, disc height, and facet angle were predictors of reoperation following surgery. Facet angle > 50° was associated with a 39% rate of reoperation, disc height > 6.5 mm was associated with a 45% rate of reoperation, and motion at spondylolisthesis > 1.25 mm was associated with a 54% rate of reoperation. Patients with all 3 risk factors for instability had a 75% rate of reoperation, whereas patients with no risk factors for instability had a 0% rate of reoperation (p = 0.14). CONCLUSIONS Patients with motion at spondylolisthesis > 1.25 mm, disc height > 6.5 mm, and facet angle > 50° are more likely to experience instability following decompression surgery for Grade I lumbar spondylolisthesis. Identification of key risk factors for instability might improve patient selection for decompression without fusion surgery.


Neurosurgical Focus | 2011

Familial Chiari malformation: case series

Benjamin D. Schanker; Brian P. Walcott; Brian V. Nahed; Kristopher T. Kahle; Yan Michael Li; Jean-Valery Coumans

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.


Neurosurgery | 2002

Use of the telescopic plate spacer in treatment of cervical and cervicothoracic spine tumors.

Jean-Valery Coumans; Connie P. Marchek; Fraser C. Henderson

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.


Acta neuropathologica communications | 2014

Sporadic hemangioblastomas are characterized by cryptic VHL inactivation

Ganesh M. Shankar; Amaro Taylor-Weiner; Nina Lelic; Robert T. Jones; James C. Kim; Joshua M. Francis; Malak Abedalthagafi; Lawrence F. Borges; Jean-Valery Coumans; William T. Curry; Brian V. Nahed; John H. Shin; Sun Ha Paek; Sung-Hye Park; Chip Stewart; Michael S. Lawrence; Kristian Cibulskis; Aaron R. Thorner; Paul Van Hummelen; Anat Stemmer-Rachamimov; Tracy T. Batchelor; Scott L. Carter; Mai P. Hoang; Sandro Santagata; David N. Louis; Fred G. Barker; Matthew Meyerson; Gad Getz; Priscilla K. Brastianos; Daniel P. Cahill

Chiari malformations (Types I-IV) are abnormalities of the posterior fossa that affect the cerebellum, brainstem, and the spinal cord with prevalence rates of 0.1%-0.5%. Case reports of familial aggregation of Chiari malformation, twin studies, cosegregation of Chiari malformation with known genetic conditions, and recent gene and genome-wide association studies provide strong evidence of the genetic underpinnings of familial Chiari malformation. The authors report on a series of 3 family pairs with Chiari malformation Type I: 2 mother-daughter pairs and 1 father-daughter pair. The specific genetic causes of familial Chiari malformation have yet to be fully elucidated. The authors review the literature and discuss several candidate genes. Recent advances in the understanding of the genetic influences and pathogenesis of familial Chiari malformation are expected to improve management of affected patients and monitoring of at-risk family members.

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Brian P. Walcott

University of Southern California

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