A Quantitative Assessment of ChatGPT as a Neurosurgical Triaging Tool.

BACKGROUND AND OBJECTIVES: ChatGPT is a natural language processing chatbot with increasing applicability to the medical workflow. Although ChatGPT has been shown to be capable of passing the American Board of Neurological Surgery board examination, there has never been an evaluation of the chatbot in triaging and diagnosing novel neurosurgical scenarios without defined answer choices. In this study, we assess ChatGPT's capability to determine the emergent nature of neurosurgical scenarios and make diagnoses based on information one would find in a neurosurgical consult. METHODS: Thirty clinical scenarios were given to 3 attendings, 4 residents, 2 physician assistants, and 2 subinterns. Participants were asked to determine if the scenario constituted an urgent neurosurgical consultation and what the most likely diagnosis was. Attending responses provided a consensus to use as the answer key. Generative pretraining transformer (GPT) 3.5 and GPT 4 were given the same questions, and their responses were compared with the other participants. RESULTS: GPT 4 was 100% accurate in both diagnosis and triage of the scenarios. GPT 3.5 had an accuracy of 92.59%, slightly below that of a PGY1 (96.3%), an 88.24% sensitivity, 100% specificity, 100% positive predictive value, and 83.3% negative predicative value in triaging each situation. When making a diagnosis, GPT 3.5 had an accuracy of 92.59%, which was higher than the subinterns and similar to resident responders. CONCLUSION: GPT 4 is able to diagnose and triage neurosurgical scenarios at the level of a senior neurosurgical resident. There has been a clear improvement between GPT 3.5 and 4. It is likely that the recent updates in internet access and directing the functionality of ChatGPT will further improve its utility in neurosurgical triage.

Web-Based Education and Social Media Increase Access to Careers in Neurosurgery: The Lenox Hill Hospital BRAINterns Experience.

OBJECTIVE: To replace educational opportunities lost during the coronavirus disease 2019 (COVID-19) pandemic, the Department of Neurosurgery at Lenox Hill Hospital produced an open-access webinar series ("BRAINterns") that covered a broad range of health care topics with a focus on neurosurgery. METHODS: This 8-week webinar series ran from July 1 to August 28, 2020. An optional exit survey was distributed to participants. Data were analyzed to characterize and better understand trends among a global cohort of participants. RESULTS: A total of 16,484 people registered for BRAINterns, and 6675 took the survey (40.5% response rate). Responders represented 87 countries, of which the majority were from the United States and Canada (90.48%, n = 6039). Responders were primarily female (82.9%, n = 5521). Racial and ethnic representation was majority Asian (42%, n = 2798), followed by White (22.7%, n = 1514), Hispanic/Latino (16.2%, n = 1080), and Black and African American (7.7%, n = 516). Participants reported hearing about BRAINterns through various social media platforms (72.18%, n = 4818)-the most popular was TikTok (33.4%, n = 2232). Overall, 93.4% of participants reported that the course was a good use of their time during the pandemic, and 86.7% reported that the course helped replace lost opportunities. CONCLUSIONS: These data demonstrate that webinar-based education is an effective method of expanding access to careers in medicine and in particular, neurosurgery, to traditionally underrepresented populations. Social media can be a powerful tool to combat barriers to early exposure and vastly improve diversity within the field.

Current Procedural Terminology-based Procedure Categorization Enhances Cost Prediction of Medicare Severity Diagnosis Related Group in Spine Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to analyze how a Current Procedural Terminology (CPT)-based categorization method can predict cost variation in surgical spine procedures. SUMMARY OF BACKGROUND DATA: Neck and back disorders affect a majority of the adult population and account for tens of billions of dollars in health care spending each year. In the era of bundled payments and value-based reimbursement, it is imperative for surgeons to identify sources of cost variability across surgical spine procedures. Historically, this has been accomplished using Medicare Severity Diagnosis Related Group (MS-DRG) codes, but they utilize an overly simplistic categorization of surgical procedures. The specificity and familiarity of the CPT coding structure makes it a better option for categorizing differences in surgical decision making and technique. METHODS: Hospital billing data for patients undergoing a surgical spine procedure requiring an overnight, in-patient stay was retrospectively collected over 4 fiscal years (2012-2016) from a single health care system. Linear regression analysis was performed to assess the correlation between cost variation and: spine-specific MS-DRG codes; a novel CPT-based categorization method; and the combination of MS-DRG codes and CPT-based categorization. RESULTS: There were 5020 surgical procedures were analyzed with respect to 16 different MS-DRG codes and 30 distinct CPT-based surgical categories (CSCs). Linear regression results were: MS-DRG R2 = 0.6545 (P < 0.001); CSC R2 = 0.5709 (P < 0.001); and R2 = 0.744 for the combined MS-DRG and CSC methods (P < 0.05). Median difference between the actual and predicted cost for the combined model was -$261.00, compared with -$727.50 for the CSC model and -$478.70 for the MS-DRG model. CONCLUSION: Addition of the CPT-based categorization method to MS-DRG coding provides an enhanced method to evaluate the association between predicted and actual cost when using linear regression analysis to assess cost variation in spine surgery.Level of Evidence: 3.

Surgeons lack of agreement on determining preoperative radiographic and clinical shoulder balance in adolescent and adult idiopathic scoliosis patients.

PURPOSE: Preoperative shoulder balance is an important factor in determining the upper instrumented vertebrae (UIV). In adolescent and adult idiopathic scoliosis (AIS/AdIS) patients, we studied the intraobserver and interobserver reliability of spinal surgeons' assessment of preoperative shoulder balance using X-rays (XR) and anterior/posterior photographs. METHODS: An observational review of a prospective multicenter database (AIS Lenke Type 1/5/6) and prospective single-institution database (AdIS) was conducted. Ten spine surgeons reviewed AIS cases; 12 spine surgeons reviewed AdIS cases. Surgeons rated the higher shoulder: left/right/same/unsure. Reliability was calculated using Fleiss' kappa coefficient. RESULTS: Among 145 Type 1 AIS cases, intraobserver reliability was moderate-to-substantial: XR (κ = 0.59), anterior photographs (κ = 0.68), posterior photographs (k = 0.65). Interobserver reliability was fair to moderate for XR (κ = 0.31), anterior photographs (κ = 0.20), and posterior photographs (κ = 0.30). Among 52 Type 5/6 AIS cases, intraobserver reliability was substantial: XR (κ = 0.70), anterior photographs (κ = 0.76), posterior photographs (κ = 0.71). Interobserver reliability was fair to moderate for XR (κ = 0.49), anterior photographs (κ = 0.47), and posterior photographs (κ = 0.36). Among 66 AdIS cases, intraobserver reliability was substantial: XR (κ = 0.68), anterior photographs (κ = 0.67), posterior photographs (κ = 0.69). Interobserver reliability was moderate for XR (κ = 0.45), anterior photographs (κ = 0.43), posterior photographs (κ = 0.49). Within Type 1 AIS patients, attendings had better intraobserver reliabilities compared to fellows using X-rays (κ = 0.61 vs. 0.53), yet no effect of surgeon experience was seen with clinical photographs. CONCLUSION: Though surgeons' ability to agree with themselves was moderate to substantial, surgeons' ability to agree with each other was fair to moderate. Combined measures to assess preoperative shoulder balance are needed for UIV selection.

A new modular radiographic classification of adult idiopathic scoliosis as an extension of the Lenke classification of adolescent idiopathic scoliosis.

PURPOSE: To propose and test the reliability of a radiographic classification system for adult idiopathic scoliosis. METHODS: A three-component radiographic classification for adult idiopathic scoliosis consisting of curve type, a lumbosacral modifier, and a global alignment modifier is presented. Twelve spine surgeons graded 30 pre-marked cases twice, approximately 1 week apart. Case order was randomized between sessions. RESULTS: The interrater reliability (Fleiss' kappa coefficient) for curve type was 0.660 and 0.798, for the lumbosacral modifier 0.944 and 0.965, and for the global alignment modifier 0.922 and 0.916, for round 1 and 2 respectively. Mean intrarater reliability was 0.807. CONCLUSIONS: This new radiographic classification of adult idiopathic scoliosis maintains the curve types from the Lenke classification and introduces the lumbosacral and global alignment modifiers. The reliability of the lumbosacral modifier and global alignment modifier shows near perfect agreement, and sets the foundation for further studies to validate the reliability, utility, and applicability of this classification system.

Partial Intraoperative Global Alignment and Proportion Scores Do Not Reliably Predict Postoperative Mechanical Failure in Adult Spinal Deformity Surgery.

STUDY DESIGN: Retrospective radiographic review. OBJECTIVES: The Global Alignment and Proportion (GAP) score allows sagittal plane analysis for deformity patients and may be predictive of mechanical complications. This study aims to assess the effectiveness of predicting mechanical failure based on partial intraoperative GAP (iGAP) scores. METHODS: A retrospective radiographic review was performed on 48 deformity patients between July 2015 to January 2017 with a 2-year follow-up. Using the same methodology as the original GAP study, the partial iGAP score was calculated with the sum of the scores for age, relative lumbar lordosis (RLL), and lordosis distribution index (LDI). Therefore, the iGAP score (0-7) was grouped into proportional (0-2), mildly disproportionate (3-5), and severely disproportionate (6-7). Logistic regression was performed to assess the ability of the partial iGAP score to predict postoperative mechanical failure. RESULTS: The mean iGAP for patients with a mechanical failure was 3.54, whereas the iGAP for those without a mechanical failure was 3.46 (P = .90). The overall mechanical failure rate was 27.1%. The mechanical failures included 8 proximal junctional kyphosis, 7 rod fractures, and 1 rod slippage from the distal end of the construct. Logistic regression analysis revealed that the partial iGAP score was not able to predict postoperative mechanical failure (χ2 = 1.4; P = .49). CONCLUSION: The iGAP scores for RLL or LDI did not show any significant correlation to postoperative mechanical failure. Ultimately, the proposed partial iGAP score did not predict postoperative mechanical failure and thus, cannot be used as an intraoperative alignment assessment to avoid postoperative mechanical complications.

Does the Global Alignment and Proportion score overestimate mechanical complications after adult spinal deformity correction?

OBJECTIVE: The goal of this study was to validate the Global Alignment and Proportion (GAP) score in a cohort of patients undergoing adult spinal deformity (ASD) surgery. The GAP score is a novel measure that uses sagittal parameters relative to each patient's lumbosacral anatomy to predict mechanical complications after ASD surgery. External validation is required. METHODS: Adult ASD patients undergoing > 4 levels of posterior fusion with a minimum 2-year follow-up were included. Six-week postoperative standing radiographs were used to calculate the GAP score, classified into a spinopelvic state as proportioned (P), moderately disproportioned (MD), or severely disproportioned (SD). A chi-square analysis, receiver operating characteristic curve, and Cochran-Armitage analysis were performed to assess the relationship between the GAP score and mechanical complications. RESULTS: Sixty-seven patients with a mean age of 52.5 years (range 18-75 years) and a mean follow-up of 2.04 years were included. Patients with < 2 years of follow-up were included only if they had an early mechanical complication. Twenty of 67 patients (29.8%) had a mechanical complication. The spinopelvic state breakdown was as follows: P group, 21/67 (31.3%); MD group, 23/67 (34.3%); and SD group, 23/67 (34.3%). Mechanical complication rates were not significantly different among all groups: P group, 19.0%; MD group, 30.3%; and SD group, 39.1% (χ2 = 1.70, p = 0.19). The rates of mechanical complications between the MD and SD groups (30.4% and 39.1%) were less than those observed in the original GAP study (MD group 36.4%-57.1% and SD group 72.7%-100%). Within the P group, the rates in this study were higher than in the original study (19.0% vs 4.0%, respectively). CONCLUSIONS: The authors found no statistically significant difference in the rate of mechanical complications between the P, MD, and SD groups. The current validation study revealed poor generalizability toward the authors' patient population.

Coronavirus Neurosurgical/Head and Neck Drape to Prevent Aerosolization of Coronavirus Disease 2019 (COVID-19): The Lenox Hill Hospital/Northwell Health Solution.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has infected more than 13 million people on a global scale and claimed more than half million deaths across 213 countries and territories. While the focus is currently on recovery from the pandemic, the disease has significantly changed the way we practice medicine and neurosurgery in New York City and the United States. Apart from the emergency cases, several health systems across the country have similarly started to perform elective surgeries. Although COVID-19 screening and testing guidelines have been proposed and adopted by many hospitals, these may not adequately protect the operating room personnel who are in proximity to the patient for prolonged periods. There are concerning reports of especially high transmission rates of COVID-19 in transmucosal head and neck procedures conducted by otolaryngologists and neurosurgeons, despite attempts at wearing what constitutes appropriate personal protective equipment. METHODS: Here, we describe a simple technique of additional draping that can be used for all cranial, endonasal, spinal, and neurointerventional cases to limit the transmission of coronavirus. RESULTS: The proposed technique offers a simple, commonly available, cost-effective alternative that avoids the use of additional retractor systems. Moreover, this technique can be used in all neurosurgical procedures. CONCLUSIONS: With the rising concerns regarding airborne spread of the virus, we expect that these precautions will prove highly useful as we enter the recovery phase of this pandemic and hospitals attempt to prevent a return to widespread infection. In addition, its availability and cost effectiveness make this technique especially attractive to practical use in centers with limited resources.

Virtual Spine: A Novel, International Teleconferencing Program Developed to Increase the Accessibility of Spine Education During the COVID-19 Pandemic.

BACKGROUND: The coronavirus identified in 2019 (COVID-19) pandemic effectively ended all major spine educational conferences in the first half of 2020. In response, the authors formed a "virtual" case-based conference series directed at delivering spine education to health care providers around the world. We herein share the technical logistics, early participant feedback, and future direction of this initiative. METHODS: The Virtual Global Spine Conference (VGSC) was created in April 2020 by a multiinstitutional team of spinal neurosurgeons and a neuroradiologist. Biweekly virtual meetings were established wherein invited national and international spine care providers would deliver case-based presentations on spine and spine surgery-related conditions via teleconferencing. Promotion was coordinated through social media platforms such as Twitter. RESULTS: VGSC recruited more than 1000 surgeons, trainees, and other specialists, with 50-100 new registrants per week thereafter. An early survey to the participants, with 168 responders, indicated that 92% viewed the content as highly valuable to their practice and 94% would continue participating post COVID-19. Participants from the United States (29%), Middle East (16%), and Europe (12%) comprised the majority of the audience. Approximately 52% were neurosurgeons, 18% orthopedic surgeons, and 6% neuroradiologists. A majority of participants were physicians (55%) and residents/fellows (21%). CONCLUSIONS: The early success of the VGSC reflects a strong interest in spine education despite the COVID-19 pandemic and social distancing guidelines. There is widespread opinion, backed by our own survey results, that many clinicians and trainees want to see "virtual" education continue post COVID-19.

A Roadmap to Reopening a Neurosurgical Practice in the Age of COVID-19.

BACKGROUND: The Coronavirus disease 2019 (COVID-19) outbreak has left a lasting mark on medicine globally. METHODS: Here we outline the steps that the Lenox Hill Hospital/Northwell Health Neurosurgery Department-located within the epicenter of the pandemic in New York City-is currently taking to recover our neurosurgical efforts in the age of COVID-19. RESULTS: We outline measurable milestones to identify the transition to the recovery period and hope these recommendations may serve as a framework for an effective path forward. CONCLUSIONS: We believe that recovery following the COVID-19 pandemic offers unique opportunities to disrupt and rebuild the historical patient and office experience as we evolve with modern medicine in a post-COVID-19 world.

A novel MRI-based classification of spinal cord shape and CSF presence at the curve apex to assess risk of intraoperative neuromonitoring data loss with thoracic spinal deformity correction.

STUDY DESIGN: Retrospective cohort. We present a simple classification system that is able to identify patients with increased odds of losing intraoperative neuromonitoring data during thoracic deformity correction. Type 3 spinal cords, with the cord deformed against the concave pedicle in the axial plane, have ×28 greater odds of losing monitoring data during surgery. OBJECTIVES: Assess preoperative morphology of the spinal cord across the thoracic concavity to predict intraoperative loss of neuromonitoring data. METHODS: 128 consecutive patients undergoing surgical correction of a thoracic deformity with pedicle screw/rod constructs were included. Spinal cords were classified into 3 types based on the appearance of the cord on the axial-T2 MRI at the apex of the curve. Type 1 is defined as a circular/symmetric cord with visible CSF between the cord and the apical concave pedicle/vertebral body. Type 2 is a circular/oval/symmetric cord with no visible CSF between the concave pedicle and the cord. Type 3 is a spinal cord that is flattened/deformed by the apical concave pedicle or vertebral body, with no intervening CSF (Fig. 1). RESULTS: 128 patients were reviewed: 81 (63%) Type 1; 32 (25%) Type 2; and 12 (11.7%) Type 3 spinal cords. Lower extremity trans-cranial motor-evoked Potentials (MEPs) and/or somatosensory evoked potentials (SSEPs) were lost intraoperatively in 21 (16%) cases, with full recovery of data in 20 of those cases. On regression analysis, a Type 1 cord was protective against intraoperative data loss (OR = 0.17, p = 0.0003). Type 2 cords had no association with data loss (OR = 0.66, p = 0.49). Type 3 cords had significantly higher odds of intraoperative data loss (OR = 28.3, p < 0.0001). CONCLUSIONS: We present a new spinal cord risk classification scheme to identify patients with increased odds of losing spinal cord monitoring data with thoracic deformity correction. The odds of losing intraoperative MEPs/SSEPs are greater in type 3 spinal cords. LEVEL OF EVIDENCE: III.

Dynamic Cord Compression Causing Cervical Myelopathy.

Due to the highly mobile nature of the cervical spine, and the fact that most magnetic resonance imagings (MRIs) and computed tomography scans are obtained only in one single position, dynamic cord compression can be an elusive diagnosis that is often missed and not well-understood. In this context, dynamic MRI (dMRI) has been utilized to improve the diagnostic accuracy of cervical stenosis. We performed a literature review on dynamic cord compression in the context of cervical spondylotic myelopathy (CSM), with particular emphasis on the role of dMRI. Cadaveric studies report that the spinal cord lengthens in flexion and the spinal canal dimension increases, whereas the spinal cord relaxes and shortens in extension and the spinal canal decreases. These changes may lead to biomechanical stress in the spinal cord with movement, especially in patients with critical cervical stenosis. The majority of the studies using dMRI in CSM reported that this imaging modality is more sensitive at detecting cervical cord compression compared to routine MRIs done in a neutral position, especially with the neck in extension. Dynamic MRI was also useful to diagnose dynamic cervical cord compression after laminectomies in patients with clinical deterioration without evident cord compression on neutral static MRI. Finally, dMRI is more sensitive in detecting stenosis in patients with CSM than in those with ossification of the posterior longitudinal ligament (OPLL), likely because OPLL patients often have a more limited range of motion than CSM patients. Thus, dMRI is a promising new tool that can help spine surgeons in diagnosing and treating CSM.

C1 Stenosis - An Easily Missed Cause for Cervical Myelopathy.

C1 stenosis is often an easily missed cause for cervical myelopathy. The vast majority of cervical myelopathy occurs in the subaxial cervical spine. The cervical canal is generally largest at C1/2, explaining the relatively rare incidence of neurological deficits in patients with odontoid fractures. However, some subjects have anatomical anomalies of the atlas, which may cause stenosis and result in clinical symptoms similar to subaxial cord compression. Isolated pure atlas hypoplasia leading to stenosis is quite rare and may be associated with other anomalies, such as atlas clefts or transverse ligament calcification. It may also be more commonly associated with syndromic conditions such as Down or Turner syndrome. Although the diagnosis can be easily made with a cervical magnetic resonance imaging, the C3/2 spinolaminar test using a lateral cervical plain radiograph is a useful and sensitive tool for screening. Surgical treatment with a C1 laminectomy is generally necessary and any atlantoaxial or occipito-atlanto instability must be treated with spinal stabilization and fusion.

Minimally invasive approach to the lumbosacral junction with a single position, 360° fusion.

Degenerative lumbar pathologies are commonly encountered at the lumbosacral junction. The transition from the mobile lumbar spine to the stiff sacroiliac segment results in high biomechanical stresses and can lead to disc degeneration, ligamentum flavum hypertrophy, neural foraminal stenosis, and other causes of pain or neurologic deficit. Surgical intervention at the lumbosacral junction must be tailored to maximize pain relief and relieve neural compression and reverse neurologic deficit while preserving the spine's natural biomechanical strength and flexibility and preventing the slow march of adjacent segment degeneration cranially into the thoracolumbar spine. It is our practice to offer combined anterior and posterior minimally invasive options when appropriate to maximize neural decompression and pain relief while ensuring proper segmental alignment and maximizing fusion rates through a minimally disruptive approach. In this article we detail a common presentation of lumbosacral pathology and the approach and considerations for a single position, minimally invasive anterior and posterior approach at the L5/S1 segment.

Dynamic Cord Compression Causing Cervical Myelopathy.

The diagnosis of cervical spondylotic myelopathy (CSM) is made based on clinical signs and symptoms, and then confirmed with magnetic resonance imaging (MRI) or CT myelogram. Due to the highly mobile nature of the cervical spine, and the fact that most MRIs and CTs are obtained only in one single position, dynamic cord compression can be an elusive diagnosis that is often missed and not well-understood. In this context, dynamic MRI (dMRI) has been utilized to improve the diagnostic accuracy of cervical stenosis in cases where static MRI does not provide enough information to establish a diagnosis or to provide additional information. We performed a literature review on dynamic cord compression in the context of CSM, with particular emphasis on the role of dynamic MRI (dMRI). Cadaveric studies report that the spinal cord lengthens in flexion and the spinal canal dimension increases, whereas the spinal cord relaxes and shortens in extension and the spinal canal decreases. These changes may lead to biomechanical stress in the spinal cord with movement, especially in patients with critical cervical stenosis. The majority of the studies using dMRI in CSM reported that this imaging modality is more sensitive at detecting cervical cord compression compared to routine MRIs done in a neutral position, especially with the neck in extension. Occult anterior compression has also been reported by some authors in flexion, but occurs less frequently. DMRI was also useful to diagnose dynamic cervical cord compression after laminectomies in patients with clinical deterioration without evident cord compression on neutral static MRI. Finally, dMRI are more sensitive in detecting stenosis in patients with CSM than in those with OPLL, likely because OPLL patients often have a more limited ROM than CSM patients. Thus, dMRI is a promising new tool that can help spine surgeons in diagnosing and treating CSM. However, further studies are needed to establish the utilization criteria and the clinical value of dMRI.

Motion-preserving, 2-stage transoral and posterior treatment of an unstable Jefferson fracture in a professional football player.

The authors report the case of a patient who suffered a Jefferson fracture during a professional football game. The C-1 (atlas) fracture was widely displaced anteriorly, but the transverse ligament was intact. In an effort to enable a return to play and avoid intersegmental (C1-2) fusion, the patient underwent a transoral approach for open reduction and internal fixation of the fracture. The associated posterior ring fracture displacement widened after this procedure, and a subsequent posterior arthrodesis and fixation of the fracture site was performed 6 months later when the fracture failed to heal with rigid collar immobilization. The approach maintained the normal range of motion at the atlantoaxial and atlantooccipital joints, which would have been sacrificed by an atlantoaxial or occipitocervical fusion, as is traditionally performed. Ultimately, the patient decided not to return to the football field, but this approach could avoid the more significant loss of motion associated with atlantoaxial or occipitocervical fusion for unstable Jefferson fractures.

The role of diffusion tensor imaging in spinal pathology: A review.

Diffusion tensor imaging (DTI) allows for noninvasive, in vivo visualization of white matter fiber tracts in the central nervous system by measuring the diffusion of water molecules. It provides both quantitative and qualitative (i.e., tractography) means to describe a region-of-interest. While protocols for the use of DTI are better established in the brain, the efficacy and potential applications of DTI in spinal cord pathology are less understood. In this review, we examine the current literature regarding the use of DTI in the spinal cord pathology, and in particular its diagnostic and prognostic value in traumatic injury, spinal tumors, cervical myelopathies, amyotrophic lateral sclerosis, and multiple sclerosis. Although structural magnetic resonance imaging (MRI) has long been the gold standard for noninvasive imaging of soft tissues, DTI provides additional tissue characteristics not found in the conventional MRI. We place emphasis on the unique characteristics of DTI, its potential value as an adjunct imaging modality, and its impact on clinical practice.

External ventricular drain practice variations: results from a nationwide survey.

OBJECTIVE While guidelines exist for many neurosurgical procedures, external ventricular drain (EVD) insertion has yet to be standardized. The goal of this study was to survey the neurosurgical community and determine the most frequent EVD insertion practices. The hypothesis was that there would be no standard practices identified for EVD insertion or methods to avoid EVD-associated infections. METHODS The American Association of Neurological Surgeons membership database was queried for all eligible neurosurgeons. A 16-question, multiple-choice format survey was created and sent to 7217 recipients. The responses were collected electronically, and the descriptive results were tabulated. Data were analyzed using the chi-square test. RESULTS In total, 1143 respondents (15.8%) completed the survey, and 705 respondents (61.6%) reported tracking EVD infections at their institution. The most common self-reported infection rate ranged from 1% to 3% (56.1% of participants), and 19.7% of respondents reported a 0% infection rate. In total, 451 respondents (42.7%) indicated that their institution utilizes a formal protocol for EVD placement. If a respondent's institution had a protocol, only 258 respondents (36.1%) always complied with the protocol. Protocol utilization for EVD insertion was significantly more frequent among residents, in academic/hybrid centers, in ICU settings, and if the institution tracked EVD-associated infection rates (p < 0.05). A self-reported 0% infection rate was significantly more commonly associated with a higher level of training (e.g., attending physicians), private center settings, a clinician performing 6 to 10 EVD insertions within the previous 12 months, and prophylactic continuous antibiotic utilization (p < 0.05). CONCLUSIONS This survey demonstrated heterogeneity in the practices for EVD insertion. No standard practices have been proposed or adopted by the neurosurgical community for EVD insertion or complication avoidance. These results highlight the need for the nationwide standardization of technique and complication prevention measures.

Anterior Cervical Discectomy and Fusion: Comparison of Fusion, Dysphagia, and Complication Rates Between Recombinant Human Bone Morphogenetic Protein-2 and Beta-Tricalcium Phosphate.

INTRODUCTION: Anterior cervical discectomy and fusion (ACDF) is one of the most common spinal procedures performed. A direct comparison of the fusion and complication rates between recombinant human bone morphogenetic protein-2 (rhBMP2) and beta-tricalcium phosphate (bTCP) has not been reported. METHODS: A retrospective study of 191 consecutive patients who underwent ACDF with polyetheretherketone plastic fusion spacers during a 2-year period with either rhBMP2 (n = 84, 46%) or bTCP (n = 107, 56%) was performed. Patients underwent 1- (35%), 2- (41%), 3- (20%), and 4- (4%) level operations. The primary outcome measure was mature arthrodesis, with secondary measures including clinical outcomes and complication occurrence. Fusion was graded on plain lateral radiographs, with median length of follow-up of 12 months. RESULTS: Rates of cervical fusion were significantly greater for patients treated with rhBMP2 than bTCP at both 6 months (70% vs. 26%, P = 0.000) and 12 months (99% vs. 85%, P = 0.000). Postoperative dysphagia was reported in 35 patients (18%), with no difference in dysphagia incidence between rhBMP2 and bTCP (20% vs. 17%, P = 0.5); however, dysphagia was more severe in the rhBMP2 group, with greater rates of readmission and steroid use (both P < 0.05). A multivariable sensitivity analyses to control for patient characteristics and number of spinal fusion levels showed no differences in dysphagia rate between rhBMP2 and bTCP. CONCLUSIONS: In our cohort, the rate of mature arthrodesis after ACDF was greater with rhBMP2 compared with bTCP with no increased incidence of postoperative dysphagia; however, dysphagia severity was greater in the rhBMP2 cohort.

Neurological outcomes following iatrogenic vascular injury during posterior atlanto-axial instrumentation.

BACKGROUND: Iatrogenic vascular injury is a feared complication of posterior atlanto-axial instrumentation. A better understanding of clinical outcome and management options following this injury will allow surgeons to better care for these patients. The object of the study was to systematically review the neurologic outcomes after iatrogenic vascular injury during atlanto-axial posterior instrumentation. METHODS: We performed a systematic review of the Medline database following PRISMA guidelines. In our analysis, we included any retrospective cohort studies, prospective cohort studies, case reports, cases series, or systematic reviews with patients who had undergone posterior atlanto-axial fusion via screw rod constructs (SRC) or transarticular screws (TAS) that reported a patient with an injury to an arterial vessel directly attributable to the surgical procedure. RESULTS: Sixty cases of vascular injury were reported in 2078 (2.9%) patients over 27 publications. The average age for this patient population was 55.7+/-17.9. Vascular injury following posterior C1/2 instrumentation resulted in ipsilateral stroke in 10.0% (n=6/60) and non-persistent neurologic deficit in 6.7% (n=4/60) of cases with the deficit being permanent (not including death) in 1.7% (n=1/60) of cases. Four patients (6.7%) died. Arteriovenous fistula or pseudoaneurysm occurred in 8.3% (n=5/60) and 3.3% (n=2/60) of cases, respectively. Eight patients (13.3%) underwent endovascular repair of the injury with no permanent deficit. CONCLUSION: Neurological morbidity after iatrogenic vascular injury during posterior C1/2 fixation is higher than previously reported in literature. Some patients may benefit from endovascular treatment. Surgeons should be aware of normal and anomalous vertebral artery anatomy to avoid this potentially catastrophic complication.