Robert J Weil

Geisinger Medical Center, Данвил, Pennsylvania, United States

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Publications (257)1162.07 Total impact

  • No preview · Chapter · Dec 2015
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    ABSTRACT: Patients with 1-3 brain metastases (BM) often receive sterotactic radiosurgery (SRS) without whole brain radiotherapy (WBRT). SRS without WBRT carries a high rate of relapse in the central nervous system (CNS). This trial used sunitinib as an alternative to WBRT for post-SRS adjuvant therapy. Eligible patients with 1-3 newly diagnosed BM, RTOG RPA class 1-2, received sunitinib after SRS. Patients with controlled systemic disease were allowed to continue chemotherapy for their primary disease according to a list of published regimens (therapy + sunitinib) included in the protocol. Patients received sunitinib 37.5 or 50 mg/days 1-28 every 42 days until CNS progression. Neuropsychological testing and MRIs were obtained every two cycles. The primary endpoint was the rate of CNS progression at 6 months (PFS6) after SRS. Fourteen patients with a median age of 59 years were enrolled. Primary cancers included lung 43 %, breast 21 %, melanoma 14 %. Toxicity included grade 3 or higher fatigue in five patients and neutropenia in two patients. The CNS PFS6 and PFS12 were 43 ± 14 and 34 ± 14 %, respectively. Of the ten patients who completed >1 neurocognitive assessment, none showed cognitive decline. Sunitinib after SRS for 1-3 BM was well tolerated with a PFS6 of 43 %. The prevention of progressive brain metastasis after SRS requires the incorporation of chemotherapy regimens to control the patient's primary disease. Future trials should continue to explore the paradigm of secondary chemoprevention of BM after definitive local therapy.
    No preview · Article · Aug 2015 · Journal of Neuro-Oncology
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    ABSTRACT: Expert opinion and a consensus statement on Cushing syndrome (CS) indicate that, in a patient with a clinical presentation and biochemical studies consistent with a pituitary etiology, the presence of a pituitary tumor ≥6 mm is highly suggestive of Cushing disease (CD). To determine the optimal pituitary tumor size that can differentiate between patients with CD and Ectopic ACTH secretion (EAS) and obviate the need for inferior petrosal sinus sampling (IPSS). Retrospective study of 130 patients seen between the years 2000 and 2012, 104 patients with CD and 26 patients with EAS. A pituitary lesion was reported in 6/26 (23%) patients with EAS and 71/104 (68.3 %) patients with CD with median (range) size of 5 mm (3-14) and 8 mm (2-31), respectively. All tumors in the EAS group measured ≤6 mm except for one which measured 14 mm. The presence of a pituitary tumor >6 mm in size had 40% sensitivity and 96% specificity for the diagnosis of CD. ACTH levels > 209 pg/mL and serum K < 2.7 mmol/L were found in patients with EAS. All patients with EAS had a 24-hr UFC more than 3.4 times the upper limit of normal (x ULN) Conclusion: Pituitary incidentalomas as large as 14 mm in size can be seen in patients with EAS. However, the 6 mm tumor size cut-off value provided 96% specificity and may be a reasonable threshold to proceed with surgery without the need for IPSS when the biochemical data support a pituitary etiology.
    No preview · Article · Jun 2015 · Endocrine Practice
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    ABSTRACT: Brain metastases (BM) occur in up to 30% of patients with cancer. Treatments include surgery, whole-brain radiotherapy (WBRT), stereotactic radiosurgery (SRS), alone or in combination. While guidelines exist, data to inform individualized approaches to therapy remain sparse. We sought to compare semi-quantitatively the effectiveness of various modalities in the treatment of single brain metastasis. We performed a comparative effectiveness analysis (CEA) that integrates efficacy, cost, and quality of life (QoL) data for alternate BM treatments. Efficacy data was obtained from a comprehensive review of current literature. Cost estimates were based on publicly available data. QoL data included the Karnofsky Performance Status (KPS) and other questionnaires. Six treatment strategies using combinations of surgery, WBRT, and SRS were compared with decision tree software. The clinical efficacy, cost, and QoL effects of each strategy were scored semi-quantitatively. We constructed a model to integrate individual preferences regarding the relative importance of efficacy, QoL, and cost to provide personalized rankings of the effectiveness of each strategy. The choice of strategy must be individualized for patients with a single BM. Our CEA and decision model combines empirical data with patient priorities to produce a ranking of alternate management strategies. Copyright © 2015 Elsevier Inc. All rights reserved.
    No preview · Article · Jun 2015 · World Neurosurgery
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    ABSTRACT: The Accreditation Council for Graduate Medical Education (ACGME) established duty-hour regulations for accredited residency programs on July 1, 2003. It is unclear what changes occurred in the national incidence of medication errors in surgical patients before and after ACGME regulations. Patient and hospital characteristics for pre- and post-duty-hour reform were evaluated, comparing teaching and nonteaching hospitals. A difference-in-differences study design was used to assess the association between duty-hour reform and medication errors in teaching hospitals. We used the Nationwide Inpatient Sample database, which consists of approximately annual 20% stratified sample of all the United States nonfederal hospital inpatient admissions. A query of the database, including 4 years before (2000-2003) and 8 years after (2003-2011) the ACGME duty-hour reform of July 2003, was performed to extract surgical inpatient hospitalizations (N = 13,933,326). The years 2003 and 2004 were discarded in the analysis to allow for a wash-out period during duty-hour reform (though we still provide medication error rates). The Nationwide Inpatient Sample estimated the total national surgical inpatients (N = 135,092,013) in nonfederal hospitals during these time periods with 68,736,863 patients in teaching hospitals and 66,355,150 in nonteaching hospitals. Shortly after duty-hour reform (2004 and 2006), teaching hospitals had a statistically significant increase in rate of medication error (p = 0.019 and 0.006, respectively) when compared with nonteaching hospitals even after accounting for trends across all hospitals during this period. After 2007, no further statistically significant difference was noted. After ACGME duty-hour reform, medication error rates increased in teaching hospitals, which diminished over time. This decrease in errors may be related to changes in training program structure to accommodate duty-hour reform. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
    No preview · Article · Jun 2015 · Journal of Surgical Education
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    ABSTRACT: We studied the impact of preoperative steroids on 30day morbidity and mortality of craniotomy for definitive resection of malignant brain tumors. Glucocorticoids are used to treat peritumoral edema in patients with malignant brain tumors, however, prolonged (⩾10days) use of preoperative steroids as a risk factor for perioperative complications following resection of brain tumors has not been studied comprehensively. Therefore, we identified 4407 patients who underwent craniotomy to resect a malignant brain tumor between 2007 and 2012, who were reported in the National Surgical Quality Improvement Program, a prospectively collected clinical database. Metastatic brain tumors constituted 37.5% (n=1611) and primary malignant gliomas 62.5% (n=2796) of the study population. We used logistic regression to assess the association between preoperative steroid use and perioperative complications before and after 1:1 propensity score matching. Patients who received steroids constituted 22.8% of the population (n=1009). In the unmatched cohort, steroid use was associated with decreased length of hospitalization (odds ratio [OR] 0.7; 95% confidence interval [CI] 0.6-0.8), however, the risk for readmission (OR 1.5; 95% CI 1.2-1.8) was increased. In the propensity score matched cohort (n=465), steroid use was not statistically associated with any adverse outcomes. Patients who received steroids were less likely to stay hospitalized for a protracted period of time, but were more likely to be readmitted after discharge following craniotomy. As an independent risk factor, preoperative steroid use was not associated with any observed perioperative complications. The findings of this study suggest that preoperative steroids do not independently compromise the short term outcome of craniotomy for resection of malignant brain tumors. Copyright © 2015 Elsevier Ltd. All rights reserved.
    No preview · Article · Jun 2015 · Journal of Clinical Neuroscience
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    ABSTRACT: Anatomic and functional hemispherectomies are relatively infrequent and technically challenging. The literature is limited by small samples and single institution data. We used the Nationwide Inpatient Sample (NIS) database to report on a large population of hemispherectomy patients and their in-hospital complication rates over a 23-year period. Between 1988 and 2010, we identified 304 pediatric hospitalizations in the NIS database where hemispherectomy was performed. Using the NIS weighting scheme, this inferred an estimated 1611 hospitalizations nationwide during this time period. Descriptive statistics were calculated on this inferred sample for patient and hospital characteristics and stratified by the presence of in-hospital complications. The adjusted odds of in-hospital complications and nonroutine discharge were estimated using multivariable models. The mean age of the patients was 5.9 years; 46% were female, and 54% were white. In the inferred series, 909 hospitalizations (56%) encountered at least 1 in-hospital complication; 42% were surgery related, and 25% were related to the hospitalization itself. For every 1-year increase in age, there was a corresponding 8% increase in the odds of a nonroutine discharge, adjusting for other potential confounders (95% confidence interval: 1.01-1.16). The most common in-hospital complication was the need for a blood transfusion (30%), followed by meningitis (10%), hydrocephalus (8%), postoperative hematoma/stroke (8%), and adverse pulmonary event (8%). Thirty-three mortalities (2%) were inferred from this series. This is the largest study to date examining hemispherectomy and associated in-hospital complication rates. This study supports early surgery in patients with medically intractable epilepsy and severe hemispheric disease. ICD-9-CM, International Classification of Diseases, 9th Revision-Clinical ModificationNIS, Nationwide Inpatient Sample.
    No preview · Article · Jun 2015 · Neurosurgery

  • No preview · Conference Paper · Jun 2015

  • No preview · Conference Paper · Jun 2015

  • No preview · Article · May 2015

  • No preview · Article · May 2015
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    ABSTRACT: We review the etiology, investigations, management and outcomes of pituitary tumor apoplexy. Pituitary tumor apoplexy is a clinical syndrome which typically includes the acute onset of headache and/or visual disturbance, cranial nerve palsy and partial or complete endocrine dysfunction. It is associated with either infarction or hemorrhage of a pre-existing pituitary adenoma and is associated with significant morbidity and potential fatality. Not all patients will present with classic signs and symptoms, therefore it is pertinent to appreciate the clinical spectrum in which this condition can present. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Full-text · Article · Mar 2015 · Journal of Clinical Neuroscience
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    ABSTRACT: Background Cushing disease (CD) is usually associated with alterations in body mass index. Successful pituitary surgery can result in long term remission with sustained weight loss. We wished to determine rates of body weight changes (in the post-operative period within 6 months) in patients with active CD who underwent transsphenoidal surgery and the relationship of weight loss to remission status Methods Clinical data was obtained from a CD database in addition to the online patient medical record. All patients with biochemically confirmed active CD underwent their first transsphenoidal surgery (TSS) by a single neurosurgeon (RJW) at the Cleveland Clinic between October 2004 and August 2013. None of the patients received glucocorticoids during surgery. Initial remission was defined by nadir cortisol <5 µg/dl, ACTH <5 pg/ml within the immediate post-operative period (72 hrs). Long term remission was defined as 24 hr UFC < ULN (upper limit of normal), and/or sequential midnight salivary cortisols <ULN, and 1mg DST cortisol <1.8 µg/dl. Statistical analyses wer performed using SAS software (Version 9.2;Cary, NC). Results Data was available for 88 patients (F:63,M:25), mean age at presentation was 47 years (range 24-87 years), median follow up 52 months (12-118 months). No significant differences in baseline demographics including pituitary adenoma size (p=0.25) and BMI (p=0.21) were observed between the two groups. 64 had no visible tumor or pituitary microadenoma, 24 were macroadenoma, 74 (84%) patients had initial remission after surgery, during follow up 6 of those with initial remission had recurrence of CS. Those with initial remission had greater mean ± SD weight loss at 3 months (kg:-8.1 ± 11.3 [initial remission, n=59] v 0.8 ± 8.8 [non-remission, n=12], p=0.007) and at 6 months (kg:-14.5 ± 12.1 [initial remission, n=46] v -6.1 ± 12.1 [non-remission, n=12], p=0.045). There was evidence that less weight loss or weight gain at three (p=0.002) and six (p=0.014) months was associated with increased risk of relapse. Conclusions After transsphenoidal surgery for CD, weight loss within the first six months is an additional early clinical indicator associated with initial biochemical remission.
    No preview · Conference Paper · Mar 2015
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    ABSTRACT: Cerebrospinal fluid shunt infection is associated with patient morbidity and high cost. We conducted a systematic review of the current evidence of comprehensive surgical protocols or individual interventions designed to reduce shunt infection incidence. A systematic review using PubMed and SCOPUS identified studies evaluating the effect of a particular intervention on shunt infection risk. Systemic prophylactic antibiotic or antibiotic-impregnated shunt efficacy studies were excluded. A total of 7429 articles were screened and 23 articles were included. Eight studies evaluated the effect of comprehensive surgical protocols. Shunt infection was reduced in all studies (absolute risk reduction 2.2-12.3 %). Level of evidence was low (level 4 in seven studies) due to the use of historical controls. Compliance ranged from 24.6 to 74.5 %. Surgical scrub with antiseptic foam and omission of a 5 % chlorhexidine gluconate preoperative hair wash were both associated with increased shunt infection. Twelve studies evaluated the effect of a single intervention. Only antibiotic-impregnated suture, a no-shave policy, and double gloving with glove change prior to shunt handling, were associated with a significant reduction in shunt infection. In a hospital with high methicillin-resistant staphylococcus aureus (MRSA) prevalence, a randomized controlled trial found that perioperative vancomycin rather than cefazolin significantly reduced shunt infection rates. Despite wide variation in compliance rates, the implementation of comprehensive surgical protocols reduced shunt infection in all published studies. Antibiotic-impregnated suture, a no-shave policy, double gloving with glove change prior to device manipulation, and 5 % chlorhexidine hair wash were associated with significant reductions in shunt infection.
    Full-text · Article · Feb 2015 · Child s Nervous System
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    ABSTRACT: Premature mortality is a public health concern that can be quantified as years of potential life lost (YPLL). Studying premature mortality from in-hospital mortality can help guide hospital initiatives and resource allocation. This paper identified the diagnosis categories associated with in-hospital deaths that account for the highest YPLL and their trends over time. Retrospective review of the Nationwide Inpatient Sample (NIS), 1988-2010. Using the NIS, YPLL on patients hospitalized in the United States from 1988 to 2010 was calculated. Hospitalizations were categorized by related principal diagnoses using the Healthcare Cost and Utilization Project (HCUP) single-level Clinical Classification Software (CCS) definitions. Between 1988 and 2010, total in-hospital estimated mortality of 20,154,186 people accounted for 198,417,257 YPLL (9.84 YPLL per in-hospital mortality; 8,626,837 estimated annual mean YPLL). The ten highest YPLL diagnosis categories accounted for 51% of the overall YPLL. The liveborn disease category (i.e., in-hospital live births) was the most common principal diagnosis and accounted for the highest YPLL at 1,070,053. The septicemia category accounted for the second highest YPLL at 548,922. The highest in-hospital mortality rate (20.8%) was associated with adult respiratory failure/insufficiency/arrest. The highest estimated in-hospital annual mean deaths occurred in patients with pneumonia at 69,134. For all in-hospital mortality, the inflation adjusted total in-hospital charges per YPLL was highest for acute myocardial infarction at $9292 per YPLL. Using YPLL, a framework has been provided to compare the impact of premature in-hospital mortality from dissimilar diseases. The methodology and results may be used to help guide further investigation of hospital quality initiatives and resource allocation. Copyright © 2014 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
    No preview · Article · Feb 2015 · Public Health
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    ABSTRACT: Object: The authors assessed the feasibility of intraoperative radiotherapy (IORT) using a portable radiation source to treat newly diagnosed, surgically resected, solitary brain metastasis (BrM). Methods: In a nonrandomized prospective study, 23 patients with histologically confirmed BrM were treated with an Intrabeam device that delivered 14 Gy to a 2-mm depth to the resection cavity during surgery. Results: In a 5-year minimum follow-up period, progression-free survival from the time of surgery with simultaneous IORT averaged (± SD) 22 ± 33 months (range 1-96 months), with survival from the time of BrM treatment with surgery+IORT of 30 ± 32 months (range 1-96 months) and overall survival from the time of first cancer diagnosis of 71 ± 64 months (range 4-197 months). For the Graded Prognostic Assessment (GPA), patients with a score of 1.5-2.0 (n = 12) had an average posttreatment survival of 21 ± 26 months (range 1-96 months), those with a score of 2.5-3.0 (n = 7) had an average posttreatment survival of 52 ± 40 months (range 5-94 months), and those with a score of 3.5-4.0 (n = 4) had an average posttreatment survival of 17 ± 12 months (range 4-28 months). A BrM at the treatment site recurred in 7 patients 9 ± 6 months posttreatment, and 5 patients had new but distant BrM 17 ± 3 months after surgery+IORT. Six patients later received whole-brain radiation therapy, 7 patients received radiosurgery, and 2 patients received both treatments. The median Karnofsky Performance Scale scores before and 1 and 3 months after surgery were 80, 90, and 90, respectively; at the time of this writing, 3 patients remain alive with a CNS progression-free survival of > 90 months without additional BrM treatment. Conclusions: The results of this study demonstrate the feasibility of resection combined with IORT at a dose of 14 Gy to a 2-mm peripheral margin to treat a solitary BrM. Local control, distant control, and long-term survival were comparable to those of other commonly used modalities. Surgery combined with IORT seems to be a potential adjunct to patient treatment for CNS involvement by systemic cancer.
    No preview · Article · Jan 2015 · Journal of Neurosurgery
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    ABSTRACT: A 54-year-old woman presented with bi-temporal hemianopia, palpitations, and diaphoresis. An invasive pituitary macroadenoma was discovered. The patient had biochemical evidence of secondary hyperthyroidism and GH excess; however, she did not appear to be acromegalic. Surgical removal of the pituitary mass revealed a plurihormonal TSH/GH co-secreting pituitary adenoma. TSH-secreting adenomas can co-secrete other hormones including GH, prolactin, and gonadotropins; conversely, co-secretion of TSH from a pituitary adenoma in acromegaly is infrequent. This case highlights an unusual patient with a rare TSH/GH co-secreting pituitary adenoma with absence of the clinical features of acromegaly.Plurihormonality does not always translate into the clinical features of hormonal excess.There appears to be a clinical and immunohistochemical spectrum present in plurihormonal tumors.
    Full-text · Article · Jan 2015
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    ABSTRACT: Background: Surgery followed by adjuvant radiotherapy is a well-established treatment paradigm for brain metastases. Objective: To examine the effect of postsurgical whole-brain radiotherapy (WBRT) or localized radiotherapy (LRT), including stereotactic radiosurgery and intraoperative radiotherapy, on the rate of recurrence both local and distal to the resection site in the treatment of brain metastases. Methods: We retrospectively identified patients who underwent surgery for brain metastasis at the Cleveland Clinic between 2004 and 2012. Institutional review board-approved chart review was conducted, and patients who had radiation before surgery, who had nonmetastatic lesions, or who lacked postadjuvant imaging were excluded. Results: The final analysis included 212 patients. One hundred fifty-six patients received WBRT, 37 received stereotactic radiosurgery only, and 19 received intraoperative radiotherapy. One hundred forty-six patients were deceased, of whom 60 (41%) died with no evidence of recurrence. Competing risks methodology was used to test the association between adjuvant modality and progression. Multivariable analysis revealed no significant difference in the rate of recurrence at the resection site (hazard ratio [HR] 1.46, P.26) or of unresected, radiotherapy-treated lesions (HR 1.70, P.41) for LRT vs WBRT. Patients treated with LRT had an increased hazard of the development of new lesions (HR 2.41, P <.001) and leptomeningeal disease (HR 2.45, P.04). Median survival was 16.5 months and was not significantly different between groups. Conclusion: LRT as adjuvant treatment to surgical resection of brain metastases is associated with an increased rate of development of new distant metastases and leptomeningeal disease compared with WBRT, but not with recurrence at the resection site or of unresected lesions treated with radiation.
    No preview · Article · Jan 2015 · Neurosurgery
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    ABSTRACT: Purpose: The Acromegaly Consensus Group recently released updated guidelines for medical management of acromegaly patients. We subjected these guidelines to a cost analysis. Methods: We conducted a cost analysis of the recommendations based on published efficacy rates as well as publicly available cost data. The results were compared to findings from a previously reported comparative effectiveness analysis of acromegaly treatments. Using decision tree software, two models were created based on the Acromegaly Consensus Group's recommendations and the comparative effectiveness analysis. The decision tree for the Consensus Group's recommendations was subjected to multi-way tornado analysis to identify variables that most impacted the value analysis of the decision tree. Results: The value analysis confirmed the Consensus Group's recommendations of somatostatin analogs as first line therapy for medical management. Our model also demonstrated significant value in using dopamine agonist agents as upfront therapy as well. Sensitivity analysis identified the cost of somatostatin analogs and growth hormone receptor antagonists as having the most significant impact on the cost effectiveness of medical therapies. Conclusion: Our analysis confirmed the value of surgery as first-line therapy for patients with surgically accessible lesions. Surgery provides the greatest value for management of patients with acromegaly. However, in accordance with the Acromegaly Consensus Group's recent recommendations, somatostatin analogs provide the greatest value and should be used as first-line therapy for patients who cannot be managed surgically. At present, the substantial cost is the most significant negative factor in the value of medical therapies for acromegaly.
    No preview · Article · Jan 2015 · Pituitary
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    ABSTRACT: Premature mortality is a public health concern that can be quantified as years of potential life lost (YPLL). Studying premature mortality can help guide hospital initiatives and resource allocation. We investigated the categories of neurologic and neurosurgical conditions associated with in-hospital deaths that account for the highest YPLL and their trends over time. Using the Nationwide Inpatient Sample (NIS), we calculated YPLL for patients hospitalized in the USA from 1988 to 2011. Hospitalizations were categorized by related neurologic principal diagnoses. An estimated 2,355,673 in-hospital deaths accounted for an estimated 25,598,566 YPLL. The traumatic brain injury (TBI) category accounted for the highest annual mean YPLL at 361,748 (33.9% of total neurologic YPLL). Intracerebral hemorrhage, cerebral ischemia, subarachnoid hemorrhage, and anoxic brain damage completed the group of five diagnoses with the highest YPLL. TBI accounted for 12.1% of all inflation adjusted neurologic hospital charges and 22.4% of inflation adjusted charges among neurologic deaths. The in-hospital mortality rate has been stable or decreasing for all of these diagnoses except TBI, which rose from 5.1% in 1988 to 7.8% in 2011. Using YPLL, we provide a framework to compare the burden of premature in-hospital mortality on patients with neurologic disorders, which may prove useful for informing decisions related to allocation of health resources or research funding. Considering premature mortality alone, increased efforts should be focused on TBI, particularly in and related to the hospital setting.
    No preview · Article · Nov 2014 · Journal of Clinical Neuroscience

Publication Stats

5k Citations
1,162.07 Total Impact Points


  • 2015
    • Geisinger Medical Center
      Данвил, Pennsylvania, United States
  • 2014-2015
    • Geisinger Health System
      Данвил, Pennsylvania, United States
    • Memorial Sloan-Kettering Cancer Center
      New York City, New York, United States
  • 2009-2015
    • Barrow Neurological Institute
      • Department of Neurosurgery
      Phoenix, Arizona, United States
  • 2005-2013
    • Cleveland Clinic
      • Department of Neurosurgery
      Cleveland, Ohio, United States
    • Northern Inyo Hospital
      BIH, California, United States
  • 2012
    • Texas Neurosurgical Institute
      Plano, Texas, United States
    • University of Cambridge
      • Department of Applied Mathematics and Theoretical Physics
      Cambridge, England, United Kingdom
  • 1998-2011
    • National Institutes of Health
      • Laboratory of Pathology
      Maryland, United States
  • 2001-2009
    • Vanderbilt University
      • Department of Biomedical Engineering
      Нашвилл, Michigan, United States
  • 2006-2008
    • Lerner Research Institute
      Cleveland, Ohio, United States
    • Universität Regensburg
      Ratisbon, Bavaria, Germany
  • 2007
    • University of Texas at San Antonio
      San Antonio, Texas, United States
  • 2005-2006
    • Sun Yat-Sen University
      Shengcheng, Guangdong, China
  • 1998-2006
    • National Cancer Institute (USA)
      • • Laboratory of Molecular Pharmacology
      • • Laboratory of Pathology
      Maryland, United States
  • 1998-2004
    • National Institute of Neurological Disorders and Strokes
      Chicago, Illinois, United States