Allan D Levi

University of Miami Miller School of Medicine, Miami, Florida, United States

Are you Allan D Levi?

Claim your profile

Publications (114)311.64 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: OBJECT Bone morphogenetic protein (BMP) is frequently used for spinal arthrodesis procedures in an "off-label" fashion. Whereas complications related to BMP usage are well recognized, the role of dosage is less clear. The objective of this meta-analysis was to assess dose-dependent effectiveness (i.e., bone fusion) and morbidity of BMP used in common spinal arthrodesis procedures. A quantitative exploratory meta-analysis was conducted on studies reporting fusion and complication rates following anterior cervical discectomy and fusion (ACDF), posterior cervical fusion (PCF), anterior lumbar interbody fusion (ALIF), transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and posterolateral lumbar fusion (PLF) supplemented with BMP. METHODS A literature search was performed to identify studies on BMP in spinal fusion procedures reporting fusion and/or complication rates. From the included studies, a database for each spinal fusion procedure, including patient demographic information, dose of BMP per level, and data regarding fusion rate and complication rates, was created. The incidence of fusion and complication rates was calculated and analyzed as a function of BMP dose. The methodological quality of all included studies was assessed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Data were analyzed using a random-effects model. Event rates are shown as percentages, with a 95% CI. RESULTS Forty-eight articles met the inclusion criteria: ACDF (n = 7), PCF (n = 6), ALIF (n = 9), TLIF/PLIF (n = 17), and PLF (n = 9), resulting in a total of 5890 patients. In ACDF, the lowest BMP concentration analyzed (0.2-0.6 mg/level) resulted in a fusion rate similar to the highest dose (1.1-2.1 mg/level), while permitting complication rates comparable to ACDF performed without BMP. The addition of BMP to multilevel constructs significantly (p < 0.001) increased the fusion rate (98.4% [CI 95.4%-99.4%]) versus the control group fusion rate (85.8% [CI 77.4%-91.4%]). Studies on PCF were of poor quality and suggest that BMP doses of ≤ 2.1 mg/level resulted in similar fusion rates as higher doses. Use of BMP in ALIF increased fusion rates from 79.1% (CI 57.6%-91.3%) in the control cohort to 96.9% (CI 92.3%-98.8%) in the BMP-treated group (p < 0.01). The rate of complications showed a positive correlation with the BMP dose used. Use of BMP in TLIF had only a minimal impact on fusion rates (95.0% [CI 92.8%-96.5%] vs 93.0% [CI 78.1%-98.0%] in control patients). In PLF, use of ≥ 8.5 mg BMP per level led to a significant increase of fusion rate (95.2%; CI 90.1%-97.8%) compared with the control group (75.3%; CI 64.1%-84.0%, p < 0.001). BMP did not alter the rate of complications when used in PLF. CONCLUSIONS The BMP doses used for various spinal arthrodesis procedures differed greatly between studies. This study provides BMP dosing recommendations for the most common spine procedures.
    No preview · Article · Nov 2015 · Journal of Neurosurgery Spine
  • Laura Bloom · S Shelby Burks · Allan D Levi
    [Show abstract] [Hide abstract]
    ABSTRACT: Postoperative wound infections in spinal surgery remain an important complication to diagnose and treat successfully. In most cases of deep infection, even with instrumentation, aggressive soft-tissue debridement followed by intravenous antibiotics is sufficient. This report presents a patient who underwent L3-S1 laminectomy and pedicle screw placement including bicortical sacral screws. This patient went on to develop multiple (7) recurrent infections at the operative site over a 5-year period. Continued investigation eventually revealed a large presacral abscess, which remained the source of recurrent bacterial seeding via the remaining bone tracts of the bicortical sacral screws placed during the original lumbar surgery. Two years after drainage of this presacral collection via a retroperitoneal approach, the patient remains symptom free.
    No preview · Article · Nov 2015 · Journal of neurosurgery. Spine
  • [Show abstract] [Hide abstract]
    ABSTRACT: Insufficient donor nerve graft material in peripheral nerve surgery remains an obstacle for successful long distance regeneration. Schwann cells (SCs) can be isolated from adult mammalian peripheral nerve biopsies and can be grown in culture and retain their capacity to enhance peripheral nerve regeneration within tubular repair strategies in multiple animal models. Human Schwann cells (hSCs) can be isolated, expanded in number and retain their ability to promote regeneration and myelinate axons but have never been tested in a clinical case of peripheral nerve injury. A sural nerve biopsy and peripheral nerve tissue from the traumatized sciatic nerve stumps was obtained after Food and Drug Administration (FDA) and Institutional Review Board (IRB) approval as well as patient consent. The SCs were isolated after enzymatic digestion of the nerve and expanded with the use of heregulin β1 (0.1 μg/ml) and forskolin (15 mM). After 2 passages - the Schwann cell isolates were combined with sural nerve grafts to repair a large sciatic nerve defect (7.5 cm) after a traumatic nerve injury. The sural nerve and the traumatized sciatic nerve ends both served as an excellent source of purified (90 and 97 % respectively) human Schwann Cells (hSCs). Using ultrasound and Magnetic Resonance Imaging (MRI) we were able to determine continuity of the nerve graft repair and the absence of tumor formation. The patient had evidence of proximal sensory recovery and definitive motor recovery distal to the repair in the distribution of the tibial and common peroneal nerve. The patient did experience an improvement in her pain scores over time. The goals of this approach were to determine the safety and clinical feasibility of implementing a new cellular repair strategy. In summary, this approach represents a novel strategy in the treatment of peripheral nerve injury and represents the first reported use of autologous cultured SCs after human peripheral nerve injury.
    No preview · Article · Nov 2015 · Cell Transplantation
  • Source
    Michael Y. Wang · Gabriel Widi · Allan D. Levi
    [Show abstract] [Hide abstract]
    ABSTRACT: Object The aging of the population will require that surgeons increasingly consider operating on elderly patients. Performing surgery safely in the elderly will require an understanding of the factors that predict successful outcomes and avoid complications. Methods Records of patients 85 years and older undergoing elective lumbar spinal surgery were retrospectively reviewed. Microdiscectomies were excluded. Preexisting medical illnesses measured using the Charlson Comorbidity Index (CCI), American Society of Anesthesiologists (ASA) Physical Status class, age, and surgical parameters were analyzed as factors potentially predictive of complications. Ambulatory function was rated on a 4-point scale. Results During the study 26 consecutive patients (mean age 87 years) with a mean ASA class of 2.6 ± 0.65 and CCI of 1.1 ± 1.27 were enrolled. The average number of levels treated was 2.17 ± 1.23, and 73% underwent fusion. The mean follow-up was 41.9 months with a minimum of 24 months, and all patients were alive at last follow-up. Average blood loss was 142 ± 184 ml, and the operative time was 183.3 ± 80.6 minutes. The mean number of levels treated was 2.17 ± 1.13 (range 1-4). Ambulatory function improved significantly by 0.59 ± 1.0 points. Five complications (19.2%) occurred in 4 patients, 2 major and 3 minor. Four complications were temporary and 1 was permanent. Patient age, blood loss, CCI score, ASA class, the number of levels treated, and fusion surgery were not statistically associated with a complication. Operative time of longer than 180 minutes (p = 0.0134) was associated with complications. Conclusions Lumbar spine surgery in patients 85 years and older can be accomplished safely if careful attention is paid to preoperative selection. Prolonged operative times are associated with a higher risk of complications.
    Preview · Article · Oct 2015 · Neurosurgical FOCUS
  • [Show abstract] [Hide abstract]
    ABSTRACT: Obje ct A systematic review of the available evidence on the prophylactic and therapeutic use of flaps for the coverage of complex spinal soft-tissue defects was performed to determine if the use of flaps reduces postoperative complications and improves patient outcomes. Met hods A PubMed database search was performed to identify English-language articles published between 1990 and 2014 that contained the following phrases to describe postoperative wounds ("wound," "complex back wound," "postoperative wound," "spine surgery") and intervention ("flap closure," "flap coverage," "soft tissue reconstruction," "muscle flap"). Results In total, 532 articles were reviewed with 17 articles meeting the inclusion criteria of this study. The risk factors from the pooled analysis of 262 patients for the development of postoperative complex back wounds that necessitated muscle flap coverage included the involvement of instrumentation (77.6%), a previous history of radiotherapy (33.2%), smoking (20.6%), and diabetes mellitus (17.2%). In patients with instrumentation, prophylactic coverage of the wound with a well-vascularized flap was shown to result in a lower incidence of wound complications. One study showed a statistically significant decrease in complications compared with patients where prophylactic coverage was not performed (20% vs 45%). The indications for flap coverage after onset of wound complications included hardware exposure, wound infection, dehiscence, seroma, and hematoma. Flap coverage was shown to decrease the number of surgical debridements needed and also salvage hardware, with the rate of hardware removal after flap coverage ranging from 0% to 41.9% in 4 studies. Con clusion s Prophylactic coverage with flaps in high-risk patients undergoing spine surgery reduces complications, while therapeutic coverage following wound complications allows the salvage of hardware in the majority of patients.
    No preview · Article · Oct 2015 · Neurosurgical FOCUS
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Perioperative blood loss is a frequent concern in spine surgery and often necessitates the use of allogeneic transfusion. Minimally invasive technique (MIS) is an option that minimizes surgical trauma and therefore intra-operative bleeding. The purpose of this study is to evaluate the blood loss, surgical complications, and duration of inpatient hospitalization in patients undergoing open posterolateral lumbar fusion (PLF), open posterior lumbar interbody fusion (PLIF) with PLF, or MIS transforaminal lumbar interbody fusion (MIS TLIF). Methods: Operative reports and perioperative data of patients undergoing single-level, primary open PLF (n=41), open PLIF/PLF (n=42), and MIS TLIF (n=71) were retrospectively evaluated. Patient demographics, operative blood loss, use of transfusion products, complications, and length of stay were tabulated. Patient data was controlled for age, BMI, and gender for statistical analysis. Results: Patients undergoing open PLF and open PLIF/PLF respectively experienced a significantly higher blood loss (p<0.001), higher volume of blood transfusion (p<0.001), higher volume of cell saver transfusion (p<0.001), and more surgical complications (dural injury, wound infections, screw malposition) (p=0.02) than those undergoing MIS TLIF. There was no statistically significant difference in duration of hospital stay (p=0.11). Conclusions: MIS TLIF provides interbody fusion with less intraoperative blood loss and subsequently a lower transfusion rate compared to open techniques, but this did not influence length of hospital stay. MIS TLIF is at least as safe as open techniques with respect to dural tear, wound infection, and screw placement. Level of evidence: Level III, Therapeutic.
    No preview · Article · Sep 2015 · The Iowa orthopaedic journal
  • J Serak · S Vanni · A D Levi
    [Show abstract] [Hide abstract]
    ABSTRACT: In addition to radiotherapy, the utility of surgical decompression and stabilization in patients with metastatic vertebral body tumors causing cord compression, progressive deformity and/or intractable pain has been well demonstrated. Minimally invasive approaches are an attractive alternative to traditional procedures as they may reduce the degree of disruption of normal anatomy, decrease blood loss, shorten hospital stays and reduce the risk of infection or wound dehiscence. The extreme lateral approach is a procedure that provides access to the anterior spine through a small incision along the flank utilizing a unique retractor system without disruption of posterior vertebral elements, spinal musculature and ligaments. A review of two senior surgeons' databases was performed between June 2010 and October 2014 to identify patients with metastatic vertebral body tumors who were treated surgically at the University of Miami during this period. We report the results of eight cases in which the extreme lateral approach was employed to perform a corpectomy and cage reconstruction for metastatic disease of the thoracic and lumbar vertebral bodies. Each case was supplemented by posterior percutaneous or less commonly open pedicle screw instrumentation. Post-operative imaging demonstrated excellent decompression of neural elements as well as deformity correction, and all patients maintained or improved neurologic function. There were no instances of wound dehiscence or infection. Our results indicate that the extreme lateral approach can be effectively used to excise metastatic vertebral body lesions of the thoracolumbar spine causing spinal cord and/or nerve root compression and spinal deformity.
    No preview · Article · Sep 2015 · Journal of neurosurgical sciences
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Ultrasound technology continues to improve with better image resolution and availability. Its use in evaluating peripheral nerve lesions is increasing. The current review focuses on the utility of ultrasound in traumatic injuries. In this report, the authors present 4 illustrative cases in which high-resolution ultrasound dramatically enhanced the anatomical understanding and surgical planning of traumatic peripheral nerve lesions. Cases include a lacerating injury of the sciatic nerve at the popliteal fossa, a femoral nerve injury from a pseudoaneurysm, an ulnar nerve neuroma after attempted repair with a conduit, and, finally, a spinal accessory nerve injury after biopsy of a supraclavicular fossa lesion. Preoperative ultrasound images and intraoperative pictures are presented with a focus on how ultrasound aided with surgical decision making. These cases are set into context with a review of the literature on peripheral nerve ultrasound and a comparison between ultrasound and MRI modalities.
    Preview · Article · Sep 2015 · Neurosurgical FOCUS
  • [Show abstract] [Hide abstract]
    ABSTRACT: Schwannomas of the brachial plexus are rare and typically present as slowly growing masses. We describe a case of a 37-year-old female who presented with acute onset of severe left upper extremity pain. Magnetic resonance imaging (MRI) showed a 2.3 × 2.1 cm peripherally enhancing centrally cystic lesion in the left axilla, along the cords of the left brachial plexus, with significant surrounding edema and enhancement. The mass was surgically removed. Pathology was consistent with a schwannoma with infarction. The pain completely resolved immediately after surgery. © The Author(s) 2015.
    No preview · Article · Jun 2015
  • Kevin S Cahill · Paul C McCormick · Allan D Levi
    [Show abstract] [Hide abstract]
    ABSTRACT: The risk of postoperative cancer following the use of recombinant human bone morphogenetic protein (BMP)-2 in spinal fusion is one potential complication that has received significant interest. Until recently, there has been little clinical evidence to support the assertion of potential cancer induction after BMP use in spinal surgery. This report aims to summarize the findings from clinical data available to date from the Yale University Open Data Access (YODA) project as well as more recently published large database studies regarding the association of BMP use in spinal fusion and the risk of postoperative cancer. A detailed review was based on online databases, primary studies, FDA reports, and bibliographies of key articles for studies that assessed the efficacy and safety of BMP in spinal fusion. In an analysis of the YODA project, one meta-analysis detected a statistically significant increase in cancer occurrence at 24 months but not at 48 months, and the other meta-analysis did not detect a significant increase in postoperative cancer occurrence. Analysis of 3 large health care data sets (Medicare, MarketScan, and PearlDiver) revealed that none were able to detect a significant increase in risk of malignant cancers when BMP was used compared with controls. The potential risk of postoperative cancer formation following the use of BMP in spinal fusion must be interpreted on an individual basis for each patient by the surgeon. There is no conclusive evidence that application of the common formulations of BMP during spinal surgery results in the formation of cancer locally or at a distant site.
    No preview · Article · Apr 2015 · Journal of neurosurgery. Spine
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Allergy to Prolene suture is exceedingly rare with only 5 cases reported in the literature. There have been no such cases associated with neurosurgical procedures. Diagnosis is nearly always delayed in spite of persistent symptomatology. A 27-year-old girl with suspected Ehlers-Danlos, connective tissue disorder, underwent posterior fossa decompression for Chiari Type 1 malformation. One year later, the patient presented with urticarial rash from the neck to chest. Cerebrospinal fluid and blood testing, magnetic resonance imaging, and intraoperative exploration did not suggest allergic reaction. Eventually skin testing proved specific Prolene allergy. After suture material was removed, the patient no longer complained of pruritus or rash. This single case highlights the important entity of allergic reaction to suture material, namely, Prolene, which can present in a delayed basis. Symptomatology can be vague but has typical allergic characteristics. Multidisciplinary approach is helpful with confirmatory skin testing as a vital part of the workup.
    Preview · Article · Jan 2015 · Case Reports in Medicine
  • Faiz U. Ahmad · Allan D. Levi

    No preview · Article · Nov 2014 · Journal of Neurosurgery Spine
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the safety and feasibility of modest hypothermia as a potential strategy for intraoperative neuroprotection during the removal of intradural spinal tumors. A retrospective review was performed for two groups of patients of a single surgeon who underwent intradural extrameduallary and intramedullary spinal tumor resection of tumors located between cervical level 1 and lumbar 2 over a 10-year period between 2001 and 2010. One cohort received intraoperative moderate hypothermia (33°C) via intravascular catheter cooling during tumor surgery and the second cohort, a historical control group of the same surgeon, underwent surgery at normothermia (≥36°C). The main outcome measured was safety as determined by surgical, medical, and neurological complications. The hypothermia (n=38) and nonhypothermia (n=34) groups were homogenous for patient demographics and baseline comorbidities. There were no differences between the groups regarding tumor level (p=0.51), tumor pathology, or intramedullary versus intradural extramedullary location (p=0.11). The hypothermia group had a lower mean body temperature (33.7°C±0.72 vs. 36.6°C±0.7, p≤0.001) longer postoperative hospital stays (10.8±14.0 vs. 7.3±4.72, p<0.001), but there were no significant differences in operative and perioperative variables such as, total anesthetic time (8.2±2.4 vs. 7.8±2.7 hours, p=0.45), total surgical time (5.9±2.1 vs. 5.7±2.5 hours, p=0.58), or estimated blood loss (483±420 vs. 420±314 mL, p=0.65). There were no statistically significant differences between the two groups with respect to the rate of surgical (3 vs. 2, p=1.0), medical (4 vs. 3, p=1.0), neurological (3 vs. 4, p=0.7), or overall complications (10 vs. 9, p=1.0). In this study, moderate hypothermia via intravascular cooling catheters was successfully performed during 38 intradural spinal tumor surgeries. Compared to the historical control group, the hypothermia patients had longer hospital stays, but did not have higher complication rates. Intraoperative moderate hypothermia during spinal tumor resection is feasible and appeared safe in this limited cohort; however, further studies with larger cohorts will be needed to determine whether peri-operative hypothermia is an effective neuroprotectant strategy in spinal tumor surgery.
    No preview · Article · Sep 2014
  • Source
    Faiz U Ahmad · Allan D Levi

    Full-text · Article · Aug 2014 · Journal of Neurosurgery Spine
  • [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Neuromata formation in the infrapatellar branch of the saphenous nerve (IPBSN) has been well described as a potential complication of arthroscopic knee surgery and knee trauma. Resection has been proven to provide improvement of pain and increased range of motion. Currently, physical examination and surgical exploration based on anatomic landmarks are the standard for intraoperative localization of IPBSN neuromas. OBJECTIVE: To demonstrate the anatomy of the IPSBN and the use of preoperative ultrasound and needle placement for localization of the nerve before sectioning. METHODS: Using both anatomic dissections and the combination of preoperative ultrasound and curved-needle placement, we demonstrate the technical nuances to localize the IPBSN before operative section. RESULTS: Cadaveric dissection is used to illustrate the main trunk of the IPSBN and its branches. In 2 cases, ultrasound guidance was effectively used to localize the saphenous nerve and its branches and facilitate the operative treatment of patients with symptomatic IPBSN neuromas. CONCLUSION: Ultrasound is a widely accepted and commonly utilized imaging modality; however, in this report, ultrasound-guided needle localization was used to aid in the resection of neuromas of small, painful sensory nerves. ABBREVIATIONS: ACL, anterior cruciate ligament IPBSN, infrapatellar branch of the saphenous nerve SBDGA, saphenous branch of the descending genicular artery US, ultrasound
    No preview · Article · Jul 2014 · Neurosurgery
  • S Shelby Burks · David J Levi · Seth Hayes · Allan D Levi
    [Show abstract] [Hide abstract]
    ABSTRACT: Unlabelled: OBJECT.: The object of this study was to highlight the challenge of insufficient donor graft material in peripheral nerve surgery, with a specific focus on sciatic nerve transection requiring autologous sural nerve graft. Methods: The authors performed an anatomical analysis of cadaveric sciatic and sural nerve tissue. To complement this they also present 3 illustrative clinical cases of sciatic nerve injuries with segmental defects. In the anatomical study, the cross-sectional area (CSA), circumference, diameter, percentage of neural tissue, fat content of the sural nerves, as well as the number of fascicles, were measured from cadaveric samples. The percentage of neural tissue was defined as the CSA of fascicles lined by perineurium relative to the CSA of the sural nerve surrounded by epineurium. Results: Sural nerve samples were obtained from 8 cadaveric specimens. Mean values and standard deviations from sural nerve measurements were as follows: CSA 2.84 ± 0.91 mm(2), circumference 6.67 ± 1.60 mm, diameter 2.36 ± 0.43 mm, fat content 0.83 ± 0.91 mm(2), and number of fascicles 9.88 ± 3.68. The percentage of neural tissue seen on sural nerve cross-section was 33.17% ± 4.96%. One sciatic nerve was also evaluated. It had a CSA of 37.50 mm(2), with 56% of the CSA representing nerve material. The estimated length of sciatic nerve that could be repaired with a bilateral sural nerve harvest (85 cm) varied from as little as 2.5 cm to as much as 8 cm. Conclusions: Multiple methods have been used in the past to repair sciatic nerve injury but most commonly, when a considerable gap is present, autologous nerve grafting is required, with sural nerve being the foremost source. As evidenced by the anatomical data reported in this study, a considerable degree of variability exists in the diameter of sural nerve harvests. Conversely, the percentage of neural tissue is relatively consistent across specimens. The authors recommend that the peripheral nerve surgeon take these points into consideration during nerve grafting as insufficient graft material may preclude successful recovery.
    No preview · Article · Apr 2014 · Journal of Neurosurgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: Complex sacral midline defects following spinal surgery have been traditionally closed with either muscle or musculocutaneous flaps. We present a case with a complicated sacral wound extending to the medulla spinalis after a lipomeningomyelocele excision in an ambulating adult. Wound was repaired with a lumbar perforator-based rotation flap. This well-vascularized flap is relatively easy to harvest, and results in minimal donor site morbidity, provides adequate dimensions, and permits primary closure of donor defect. In addition, the flap allows for anatomic muscle approximation without sacrificing the muscle functions, and provides reliable soft tissue coverage. Level of Evidence: Level V, therapeutic study.
    No preview · Article · Mar 2014 · European Journal of Plastic Surgery
  • Source
    Yerko A Berrocal · Vania W Almeida · Allan D Levi

    Full-text · Article · Feb 2014 · Journal of Neurosurgery
  • Article: Response.

    No preview · Article · Jan 2014 · Journal of neurosurgery. Spine
  • Source
    M F Khan · S S Burks · H Al-Khayat · AD Levi
    [Show abstract] [Hide abstract]
    ABSTRACT: Study design:Retrospective case-controlled study.Objectives:To understand the incidence of gastrointestinal hemorrhage (GIH) and subsequent mortality rate associated with steroid use after acute spinal cord injury (SCI).Setting:Miami, Florida, USA.Methods:This case-controlled study investigates two sequential study groups with SCI treated by a single surgeon in a level I trauma center. The first study cohort (1997-2005) received steroids according to the NASCIS II protocol and the second (2005-2012) received no steroid treatment. The groups were comparable with respect to age, sex, severity and level of injury (43 vs 45 years old/3:1 male-female/AIS scale %-43.5 vs 41.7 A, 10.6 vs 11.1 B, 20.3 vs 13.4 C, 25.4 vs 33.5 D/64.3 vs 73.8% cervical, 35.6 vs 25.7% thoracic and lumbar). The incidence and mortality from GIH were the primary outcome measures.Results:A total of 350 patients were evaluated during the study period. The incidence of GIH in the SCI group receiving steroids was 6/216 (2.77%) with 2 mortalities (33.3%). No gastrointestinal (GI) complications were noted in the 134 patients that did not receive any steroids (P=0.086). All GIH cases in the steroid group were in cervical SCI patients-6/139 (4.32%; P=0.043). Average time to onset of GIH was 16 days.Conclusion:The use of steroids in acute SCI appears to be a key risk factor in increasing the incidence of clinically overt GI complications with a subsequent high mortality rate, particularly in patients with cervical SCI.Spinal Cord advance online publication, 22 October 2013; doi:10.1038/sc.2013.122.
    Full-text · Article · Oct 2013 · Spinal Cord

Publication Stats

3k Citations
311.64 Total Impact Points


  • 1995-2015
    • University of Miami Miller School of Medicine
      • • Department of Neurological Surgery
      • • Miami Project to Cure Paralysis
      Miami, Florida, United States
  • 1994-2015
    • University of Miami
      • • Department of Neurological Surgery
      • • Department of Medicine
      • • Miami Project to Cure Paralysis
      كورال غيبلز، فلوريدا, Florida, United States
  • 1998-2011
    • Jackson Memorial Hospital
      • Department of Radiology
      Miami, Florida, United States
  • 1994-2006
    • University of Toronto
      • Department of Surgery
      Toronto, Ontario, Canada
  • 2003
    • Keck School of Medicine USC
      Los Ángeles, California, United States
  • 2000
    • Laval University
      Quebec City, Quebec, Canada
  • 1997-1998
    • Barrow Neurological Institute
      • Department of Neurosurgery
      Phoenix, Arizona, United States