OBJECTIVECommon interbody graft options for anterior cervical discectomy and fusion (ACDF) include allograft and polyetheretherketone (PEEK). PEEK has gained popularity due to its radiolucent properties and a modulus of elasticity similar to that of bone. PEEK devices also result in higher billing costs than allograft, which may drive selection. A previous study found a 5-fold higher rate of pseudarthrosis with the use of PEEK devices compared with structural allograft in single-level ACDF. Here the authors report on the occurrence of pseudarthrosis with PEEK devices versus structural allograft in patients who underwent multilevel ACDF.METHODSThe authors retrospectively reviewed 81 consecutive patients who underwent a multilevel ACDF and had radiographic follow-up for at least 1 year. Data were collected on age, sex, BMI, tobacco use, pseudarthrosis, and rate of reoperation for pseudarthrosis. Logistic regression was used for data analysis.RESULTSOf 81 patients, 35 had PEEK implants and 46 had structural allograft. There were no significant differences between age, sex, smoking status, or BMI in the 2 groups. There were 26/35 (74%) patients with PEEK implants who demonstrated radiographic evidence of pseudarthrosis, compared with 5/46 (11%) patients with structural allograft (p < 0.001, OR 22.2). Five patients (14%) with PEEK implants required reoperation for pseudarthrosis, compared with 0 patients with allograft (p = 0.013).CONCLUSIONSThis study reinforces previous findings on 1-level ACDF outcomes and suggests that the use of PEEK in multilevel ACDF results in statistically significantly higher rates of radiographic pseudarthrosis and need for revision surgery than allograft. Surgeons should consider these findings when determining graft options, and reimbursement policies should reflect these discrepancies.

OBJECTIVEThe advent of the internet and the popularity of e-learning resources has promoted a shift in medical and surgical education today. The Neurosurgical Atlas has sought to capitalize on this shift by providing easily accessible video and online education to its users on an international scale. The rising popularity of social media has provided new avenues for expanding that global reach, and the Atlas has sought to do just that. In this study, the authors analyzed user demographics and web traffic patterns to quantify the international reach of the Atlas and examined the potential impact of social media platforms on the expansion of that reach.METHODSTwitter, Facebook, and Instagram metrics were extracted using each respective service’s analytics tool from the date of their creation through October 2019. Google Analytics was used to extract website traffic data from September 2018 to September 2019 and app data from January 2019 to October 2019. The metrics extracted included the number of platform users/followers, user demographic information, percentage of new versus returning visitors, and a number of platform-specific values.RESULTSSince the authors’ previous publication in 2017, annual website viewership has more than doubled to greater than 500,000 viewing sessions in the past year alone; international users accounted for more than 60% of the visits. The Atlas Twitter account, established in August 2012, has more than 12,000 followers, primarily hailing from the United States, the United Kingdom, Canada, and Saudi Arabia. The Atlas Facebook account, established in 2013, has just over 13,000 followers, primarily from India, Egypt, and Mexico. The Atlas Instagram account (established most recently, in December 2018) has more than 16,000 followers and the highest percentage (31%) of younger users (aged 18–24 years). The Atlas app was officially launched in May 2019, largely via promotion on the Atlas social media platforms, and has since recorded more than 60,000 viewing sessions, 80% of which were from users outside the United States.CONCLUSIONSThe Neurosurgical Atlas has attempted to leverage the many e-learning resources at its disposal to assist in spreading neurosurgical best practice on an international scale in a novel and comprehensive way. By incorporating multiple social media platforms into its repertoire, the Atlas is able to ensure awareness of and access to these resources regardless of the user’s location or platform of preference. In so doing, the Atlas represents a novel way of advancing access to neurosurgical educational resources in the digital age.

OBJECTIVEHemifacial spasm (HFS), largely caused by neurovascular compression (NVC) of the facial nerve, is a rare condition characterized by paroxysmal, unilateral, involuntary contraction of facial muscles. It has long been suggested that these symptoms are due to compression at the transition zone of the facial nerve. The aim of this study was to examine symptom-free survival and long-term quality of life (QOL) in HFS patients who underwent microvascular decompression (MVD). A secondary aim was to examine the benefit of utilizing fused MRI and MRA post hoc 3D reconstructions to better characterize compression location at the facial nerve root exit zone (fREZ).METHODSThe authors retrospectively analyzed patients with HFS who underwent MVD at a single institution, combined with a modified HFS-7 telephone questionnaire. Kaplan-Meier analysis was used to determine event-free survival, and the Wilcoxon signed-rank test was used to compare pre- and postoperative HFS-7 scores.RESULTSThirty-five patients underwent MVD for HFS between 2002 and 2018 with subsequent 3D reconstructions of preoperative images. The telephone questionnaire response rate was 71% (25/35). If patients could not be reached by telephone, then the last clinic follow-up date was recorded and any recurrence noted. Twenty-four patients (69%) were symptom free at longest follow-up. The mean length of follow-up was 2.4 years (1 month to 8 years). The mean symptom-free survival time was 44.9 ± 5.8 months, and the average symptom-control survival was 69.1 ± 4.9 months. Four patients (11%) experienced full recurrence. Median HFS-7 scores were reduced by 18 points after surgery (Z = −4.013, p < 0.0001). Three-dimensional reconstructed images demonstrated that NVC most commonly occurred at the attached segment (74%, 26/35) of the facial nerve within the fREZ and least commonly occurred at the traditionally implicated transition zone (6%, 2/35).CONCLUSIONSMVD is a safe and effective treatment that significantly improves QOL measures for patients with HFS. The vast majority of patients (31/35, 89%) were symptom free or reported only mild symptoms at longest follow-up. Symptom recurrence, if it occurred, was within the first 2 years of surgery, which has important implications for patient expectations and informed consent. Three-dimensional image reconstruction analysis determined that culprit compression most commonly occurs proximally along the brainstem at the attached segment. The success of this procedure is dependent on recognizing this pattern and decompressing appropriately. Three-dimensional reconstructions were found to provide much clearer characterization of this area than traditional preoperative imaging. Therefore, the authors suggest that use of these reconstructions in the preoperative setting has the potential to help identify appropriate surgical candidates, guide operative planning, and thus improve outcome in patients with HFS.

No abstract

OBJECTIVEDespite rapid development and expansion of neuromodulation technologies, knowledge about device and/or therapy durability remains limited. The aim of this study was to evaluate the long-term rate of hardware and therapeutic failure of implanted devices for several neuromodulation therapies.METHODSThe authors performed a retrospective analysis of patients’ device and therapy survival data (Kaplan-Meier survival analysis) for deep brain stimulation (DBS), vagus nerve stimulation (VNS), and spinal cord stimulation (SCS) at a single institution (years 1994–2015).RESULTSDuring the study period, 450 patients underwent DBS, 383 VNS, and 128 SCS. For DBS, the 5- and 10-year initial device survival was 87% and 73%, respectively, and therapy survival was 96% and 91%, respectively. For VNS, the 5- and 10-year initial device survival was 90% and 70%, respectively, and therapy survival was 99% and 97%, respectively. For SCS, the 5- and 10-year initial device survival was 50% and 34%, respectively, and therapy survival was 74% and 56%, respectively. The average initial device survival for DBS, VNS, and SCS was 14 years, 14 years, and 8 years while mean therapy survival was 18 years, 18 years, and 12.5 years, respectively.CONCLUSIONSThe authors report, for the first time, comparative device and therapy survival rates out to 15 years for large cohorts of DBS, VNS, and SCS patients. Their results demonstrate higher device and therapy survival rates for DBS and VNS than for SCS. Hardware failures were more common among SCS patients, which may have played a role in the discontinuation of therapy. Higher therapy survival than device survival across all modalities indicates continued therapeutic benefit beyond initial device failures, which is important to emphasize when counseling patients.

OBJECTIVEGlossopharyngeal neuralgia (GN) is a rare pain condition in which patients experience paroxysmal, lancinating throat pain. Multiple surgical approaches have been used to treat this condition, including microvascular decompression (MVD), and sectioning of cranial nerve (CN) IX and the upper rootlets of CN X, or a combination of the two. The aim of this study was to examine the long-term quality of life and pain-free survival after MVD and sectioning of the CN X/IX complex.METHODSA combined retrospective chart review and a quality-of-life telephone survey were performed to collect demographic and long-term outcome data. Quality of life was assessed by means of a questionnaire based on a combination of the Barrow Neurological Institute pain intensity scoring criteria and the Brief Pain Inventory–Facial. Kaplan-Meier analysis was performed to determine pain-free survival.RESULTSOf 18 patients with GN, 17 underwent sectioning of the CN IX/X complex alone or sectioning and MVD depending on the presence of a compressing vessel. Eleven of 17 patients had compression of CN IX/X by the posterior inferior cerebellar artery, 1 had compression by a vertebral artery, and 5 had no compression. One patient (6%) experienced no immediate pain relief. Fifteen (88%) of 17 patients were pain free at the last follow-up (mean 9.33 years, range 5.16–13 years). One patient (6%) experienced throat pain relapse at 3 months. The median pain-free survival was 7.5 years ± 10.6 months. Nine of 18 patients were contacted by telephone. Of the 17 patients who underwent sectioning of the CN IX/X complex, 13 (77%) patients had short-term complaints: dysphagia (n = 4), hoarseness (n = 4), ipsilateral hearing loss (n = 4), ipsilateral taste loss (n = 2), and dizziness (n = 2) at 2 weeks. Nine patients had persistent side effects at latest follow-up. Eight of 9 telephone respondents reported that they would have the surgery over again.CONCLUSIONSSectioning of the CN IX/X complex with or without MVD of the glossopharyngeal nerve is a safe and effective surgical therapy for GN with initial pain freedom in 94% of patients and an excellent long-term pain relief (mean 7.5 years).

Background Maximal safe resection remains a key principle in infiltrating glioma management. Stimulation mapping is a key adjunct for minimizing functional morbidity while “fence-post” procedures use catheters or dye to mark the tumor border at the start of the procedure prior to brain shift. Objective To report a novel technique using stereotactically placed electrodes to guide tumor resection near critical descending subcortical fibers. Methods Navigated electrodes were placed prior to tumor resection along the deep margin bordering presumed eloquent tracts. Stimulation was administered through these depth electrodes for subcortical motor and language mapping. Results Twelve patients were included in this preliminary technical report. Seven patients (7/12, 58%) were in asleep cases, while the other 5 cases (5/12, 42%) were performed awake. Mapping of motor fibers was performed in 8 cases, and language mapping was done in 1 case. In 3 cases, both motor and language mapping were performed using the same depth electrode spanning corticospinal tract and the arcuate fasciculus. Conclusion Stereotactic depth electrode placement coupled with stimulation mapping of white matter tracts can be used concomitantly to demarcate the border between deep tumor margins and eloquent brain, thus helping to maximize extent of resection while minimizing functional morbidity.

To the Editor:We read with great interest the article by Atli et al, 1 which highlights virtual reality as a means to modernizing neurosurgical education. We believe this article is of profound academic importance and aim to present an additional valuable resource in neurosurgery for current and aspiring medical students. Here, we discuss the evolution of the various online platforms within organized neurosurgery throughout the 21st century.As a resident at the University of Maryland, Dr Mark Iguchi initiated in 2006 the first such platform through NS Match, calling it Neurosurgery Online. This site was short lived as it did not possess the infrastructure to sustain interest from medical students and young surgeons alike. However, it did highlight the need for a platform wherein current and aspiring neurosurgeons could engage and learn from seasoned attendings and medical students could find resources on things like navigating the neurosurgery match.In 2007, Dr Kenneth Liu, a resident at the University of Oregon, helped to fill these gaps with the platform Uncle Harvey. The original Uncle Harvey allowed students to engage across the spectrum of neurosurgery with residents, fellows, attendings, and peers. Each forum within Uncle Harvey helped cover a distinct topic within neurosurgery, with the addition of space for case presentations from leaders in the field. By 2012, Uncle Harvey fell in the ranks following a perceived plateau in usership. That same year, a similar yet lesser known platform, Legacy NsgyApplicants, served as the only online neurosurgical forum available for the next 3 yr. By 2015, however, resources from Legacy NsgyApplicants were no longer accessible.In 2016, a resident at the University of Buffalo picked up the baton and created Neurosurgery Hub. Neurosurgery Hub broadcasted to a wider audience and contained separate forums for students, residents, fellows, and attendings on both the national and international scales. It offered a unique space for discussing interesting cases, providing easy-access resource links, and publishing employment listings. Unlike its predecessors, Neurosurgery Hub content was accessible without registration.In 2020, a student-led initiative sought to join forces with the original creator of Neurosurgery Hub to distill the best parts of the site, along with those of its predecessors, into the new and improved Uncle Harvey 2.0. The revised Uncle Harvey maintained the forums, resources, and job listings seen previously, but added forum moderation, a blog, research opportunities, a YouTube channel, and an expanded residency program review functionality in an effort to provide a "one-stop shop" for all of neurosurgery.