A Descriptive Analysis: Infants Presenting to the Pediatric Emergency Department With a Brief Resolved Unexplained Event.

OBJECTIVES: Infants presenting to pediatric emergency departments (EDs) after a choking episode, cyanotic event, or irregular breathing pattern are often diagnosed with a brief, resolved, unexplained event (BRUE). Social determinants of health may affect these patients; therefore, we aimed to define population demographics and determine significant demographic predictors between 2 cohorts-infants presenting with BRUE, and those admitted to the intensive care unit. METHODS: Using data from the Pediatric Health Information System (Children's Hospital Association, Washington, DC, Lenexa, KS), this multicenter, retrospective study included children aged 0-1 year from 52 hospitals who presented with an International Classification of Diseases-10 coded primary diagnosis for BRUE/apparent life-threatening event (ALTE) between January 1, 2016, and June 30, 2021. Cohort 1 patients presented to the ED with BRUE; cohort 2 patients were admitted from the ED for BRUE. Univariate and multivariate logistic regression were performed for both cohorts to discover possible demographic predictors. RESULTS: Overall, 24,027 patients were evaluated. Patient sex did not affect admission rates (odds ratio [OR] = 1.034; 95% confidence interval [CI], 0.982-1.089; P = 0.2051). Black race (OR = 1.252; 95% CI, 1.177-1.332; P < 0.0001) and Medicaid insurance (OR = 1.126; 95% CI, 1.065-1.19; P < 0.0001) were significantly associated with an increased risk of admission. "Other" race (OR = 0.837; 95% CI, 0.777-0.902; P < 0.0001) and commercial insurance were significantly associated with a greater likelihood of discharge (OR = 0.888; 95% CI, 0.84-0.939; P < 0.0001). CONCLUSIONS: Black race and Medicaid insurance predicted admission in this patient population, but demographics did not play a role in intensive care unit admission overall. Social determinants of health and demographics therefore appeared to play a role in admission for patients presenting to the ED. Future research could evaluate the effect of focused interventions, such as providing additional resources to socially at-risk families through community outreach, on admission rates of patients with these specific at-risk demographics.

Comparing the Use of Crotaline-Polyvalent Immune Fab (Ovine) Versus Observation in Children.

OBJECTIVES: In the United States, studies are inconclusive regarding the indications for polyvalent antivenom administration for crotaline envenomation. We compared polyvalent antivenom administration versus observation used at 2 separate institutions. We hypothesized that deferring antivenom leads to increased hospital length of stay and surgical interventions. METHODS: Retrospective chart review of children who presented to Le Bonheur Children's Hospital (LBCH) in Memphis, Tennessee, and Monroe Carell Jr Children's Hospital at Vanderbilt (MCJCHV) in Nashville, Tennessee, from 2009 to 2021. Patient demographics, treatment utilization, bite location, and outcomes from both sites were statistically examined. RESULTS: A total of 183 patients met the inclusion criteria (123 at LBCH, 60 at MCJCHV). At LBCH, mean age was 9.2 years, 54% were male, and 79% of known snakes identified as copperheads. At MCJCHV, mean age was 8.9 years, 65% were male, and 88% of known snakes identified as copperheads. The most commonly envenomated areas for both sites were the foot (42%), hand (27%), and ankle (26%). Patients at LBCH were managed with antivenom only 25% of the time, whereas 75% were observed; 82% of MCJCHV patients were managed with antivenom (P < 0.001). There were no significant differences in length of stay (mean, 1.5 days at LBCH and 1.8 days at MCJCHV; P = 0.136) or surgical intervention (3.3% of LBCH encounters, 5.0% of MCJCHV encounters; P = 0.685). Secondary outcomes aside from coagulopathy and admission location (intensive care unit vs floor) were also not significant. CONCLUSIONS: The use of antivenom did not impact hospital length of stay or surgical interventions. Our results should be interpreted cautiously as our study reflects regional experiences with snake species in the Southeast United States and not North America as a whole. Other institutional differences in management and smaller n at MCJCHV may have contributed to different outcomes. Further study is needed to determine intermediate and long-term effects of deferring antivenom use.

Pre-operative embolization for staged treatment of infantile choroid plexus papilloma.

Choroid plexus papillomas (CPPs) are benign but rare neuroepithelial neoplasms of the choroid plexus that represent the non-malignant form of a spectrum of tumors of the choroid plexus. The vast majority of CPPs present in children under 5 years of age. Some CPPs are diagnosed prenatally, but many of them reach a large size before diagnosis. CPPs typically present with signs and symptoms of hydrocephalus. Treatment of these tumors has traditionally been with surgical resection. Large CPPs in young children present a challenge due to risk of high blood loss during resection. Here, the authors describe the case of a 3-month-old presenting with hydrocephalus and a large CPP of the third ventricle that was managed with a staged strategy of embolization followed by a delayed resection, allowing the tumor to involute prior to surgery.

The overshadowed scientific endeavours of Berengario Da Carpi, a renaissance physician and the Forerunner of neurosurgery: a historical vignette.

Jacopo Berengario da Carpi was Renaissance-era physician, surgeon, and anatomy lecturer who transformed medieval anatomy and surgery-which were, at the time, dominated mostly by religious dogma-into a modern science based on direct observation, experience, and cadaveric dissection. He was an accomplished and innovative neuroanatomist and educator, a prolific researcher and publisher, and a successful practicing surgeon who treated the head injuries of many renowned patients of that period. He published a landmark commentary on skull fractures that was the first printed book in history devoted to head injuries, which became a model of new medical understanding. Nonetheless, Berengario's achievements in anatomy, medicine, neuroanatomy, and what would later become neurotraumatology and neurosurgery, would have been more widely known had his work and research not been surpassed by Andreas Vesalius and Ambroise Paré, both of whom advanced anatomic and medical knowledge even further. In this historical vignette, we discuss the political conditions of sixteenth Century Italy and pay a homage to Berengario da Carpi, emphasizing his work in establishing neuroanatomy as a field of medicine that became a precursor to modern neuroscience. We also describe the improvements he made in neurotraumatology technique and instrumentation, and his explanations of skull fractures and other brain injuries outlined in ground-breaking clinical books he published. Finally, we try to elucidate possible reasons why his scientific and professional achievements-despite of their enormous impact-were overshadowed by the achievements of his more famous immediate successors.

Vagus nerve stimulation (VNS) therapy update.

Epilepsy affects millions of people worldwide. Approximately one-third have pharmacoresistant epilepsy, and of these, the majority are not candidates for epilepsy surgery. Vagus nerve stimulation (VNS) therapy has been an option to treat pharmacoresistant seizures for 30 years. In this update, we will review the clinical data that support the device's efficacy in children, adolescents, and adults. We will also review its side-effect profile, quality of life and cost benefits, and the impact the device has on sudden unexpected death in epilepsy (SUDEP). We will then discuss candidate selection and provide guidance on dosing and future models. Vagus nerve stimulation therapy is an effective treatment for many seizure types and epilepsy syndromes with a predictable and benign side-effect profile that supports its role as the most commonly prescribed device to treat pharmacoresistant epilepsy. "This article is part of the Supplement issue Neurostimulation for Epilepsy."

The Development of Skull Base Surgery as a Discipline: Remembrances of Dr Jon H. Robertson.

Skull base surgery is a young surgical subspecialty currently led by its second generation of surgeons. At present, there is no literature that narrates the connection of the present to the past. An extended interview was held with Dr Jon H. Robertson, who helped establish the subspecialty in Memphis, TN, to aid in identifying and connecting sentinel events and key figures in the development of the discipline. The field drastically evolved during his era of practice (1975-present), with the advent of advanced imaging and technology, as well as the emergence of multidisciplinary skull base surgical teams. The intersection of the careers of Jon H. Robertson, James T. Robertson, Gale Gardner, Edwin Cocke, John Shea, Jr., and Jerrall Crook in Memphis catalyzed the standardization of a multidisciplinary approach to cranial base pathology. We report the findings of Dr Jon H. Robertson's extended interview, told against the backdrop of the history of the subspecialty. The story of the development of skull base surgery is told from the unique perspective of one who lived and shaped a pivotal segment in this historical timeline.

A Scoping Review of Professionalism in Neurosurgery.

BACKGROUND AND OBJECTIVES: The Accreditation Council for Graduate Medical Education's Milestones provides a foundation for professionalism in residency training. Specific professionalism concepts from neurosurgery could augment and expand milestones for the specialty. We reviewed the current literature and identified professionalism concepts within the context of neurosurgical practice and training. METHODS: We used a scoping review methodology to search PubMed/MEDLINE and Scopus and identify English-language articles with the search terms "professionalism" and "neurosurgery." We excluded articles that were not in English, not relevant to professionalism within neurosurgery, or could not be accessed. Non-peer-reviewed and qualitative publications, such as commentaries, were included in the review. RESULTS: A total of 193 articles were included in the review. We identified 6 professionalism themes among these results: professional identity (n = 53), burnout and wellness (n = 51), professional development (n = 34), ethics and conflicts of interest (n = 27), diversity and gender (n = 19), and misconduct (n = 9). CONCLUSION: These 6 concepts illustrate concerns that neurosurgeons have concerning professionalism. Diversity and gender, professional identity, and misconduct are not specifically addressed in the Accreditation Council for Graduate Medical Education's Milestones. This review could be used to aid the development of organizational policy statements on professionalism.

Cranial Versus Cervical Spine Magnetic Resonance Imaging in Adult Chiari Malformation Type I Diagnostics: Is There a Difference in Tonsil Ectopia Length?

BACKGROUND: Chiari malformation type 1 (CM-1) diagnosis is based on measurement of the cerebellar tonsils on cranial or cervical spine magnetic resonance imaging (MRI). However, imaging parameters of cranial and cervical spine MRI could differ because spine MRI has greater resolution. METHODS: We conducted a retrospective chart review of 161 patients of a single neurosurgeon for adult CM-I consultation between February 2006 and March 2019. Patients were selected based on receiving both cranial and cervical spine MRI within a month of each other to determine tonsillar ectopia length for CM-1. Ectopias were measured to determine if differences in values were statistically significant. RESULTS: From the 161 total patients, 81 had cranial and cervical spine MRI for a total of 162 tonsil ectopia measurements (81 cranial and 81 spinal). Average ectopia length on a cranial MRI was 9.1 mm (±5.2 mm); average ectopia length on a spinal MRI was 8.9 mm (±5.3 mm). Average cranial and spinal MRI values were found to be <1 standard deviation apart. Two-tailed, nonequal variances t test determined that differences between the cranial and spinal ectopia measurements were insignificant (P = 0.2403). CONCLUSIONS: This study confirmed that the added resolution offered by spine MRI did not make better or more refined measurements over cranial MRI that could lead to measurement differences, which can instead be attributed to chance. Cranial and cervical spine MRI can be used to determine the degree of the tonsil ectopia.

Dispensary Cannabidiol (CBD): Nothing to Worry About!

Introduction: Despite US FDA approval of cannabidiol (CBD) liquid (Epidiolex®), patients with epilepsy still supplement prescription treatments with dispensary CBD. This study aimed to evaluate therapeutic effectiveness of dispensary CBD. Methods: We retrospectively collected dosage information, CBD serum levels, efficacy, and adverse effects from patient charts (children, adolescents, adults) (n = 18). Results: All 18 patients showed no clinical benefit from dispensary CBD as detectable serum levels never reached a therapeutic range of 150 ng/mL (6 patients had barely detectable levels that were below laboratory reporting thresholds). Minute levels of tetrahydrocannabinol (THC) were found in 3 patients, and moderate levels were found in 1 patient. Conclusion: Dispensary CBD failed to reach effective therapeutic levels in all of these patients. The presence of THC demonstrates the current lack of regulation of dispensary CBD. Anecdotal reports of clinical effectiveness should be considered an effect of concomitant prescription antiseizure medications and not dispensary CBD.

Bibliometric Analysis of 6 Major European Neurosurgical Publications from 2011-2020 (part 3): a Comparative Metrics Review.

Background: We previously conducted bibliometric analysis of 6 North American neurosurgical journals. Objective: To perform a bibliometric analysis of 6 European neurosurgical journals to build on our previous studies. Methods: We searched Web of Science for articles published in Acta Neurochirurgica, British Journal of Neurosurgery, Child's Nervous System, Journal of Neurological Surgery Part A: Central European Neurosurgery, Journal of Neurosurgical Sciences, and Neurosurgical Review between 2011 and 2020. We analyzed bibliometric parameters related to total annual document distribution, author metrics, journal metrics, country and continental distribution, institution, keywords, and journal impact. Results: European countries provided the greatest contributions. Acta Neurochirurgica followed by Child's Nervous System published the greatest number of articles and had the highest h-index and number of citations. From 2018 to 2020, total documents increased 79.6%, original articles increased 86.5%, review articles increased 103.6%, citations increased 79.6%, number of publishing authors increased 72.1%, number of authors in multi-author documents increased 72.4%, and author's keywords and keywords plus increased 72.4% and 27.0%, respectively. The collaboration index decreased 5.3% from 4.49 to 4.25. Annual published documents and citations were lower for European journals versus North American journals. Conclusion: Several parameters of the European journals increased by 2020. One interesting finding is that growth for the 6 journals dramatically increased in the 2 years prior to the COVID-19 pandemic. While neurosurgeon free time during lockdowns may account for much of the increase in 2020, the trend began before this. Our analysis did not identify a cause for the pre-COVID increases.

Effect of Body Mass Index on Chiari Malformation 1 Tonsil Ectopia Length in Adults.

OBJECTIVE: Diagnosis of Chiari I malformation (CM-1) is based on measurements of the inferior extension of the cerebellar tonsils into the foramen magnum on cranial or cervical spine magnetic resonance imaging. Imaging may be obtained before the patient is referred to the neurosurgical specialist. The length of time raises questions about the possibility that body mass index (BMI) fluctuations could affect the measurement of ectopia length. However, previous literature on BMI and CM-1 has reported conflicting findings on BMI. METHODS: We conducted a retrospective chart review of 161 patients who were referred to a single neurosurgeon for CM-1 consultation. Patients with multiple recorded BMI values (n = 71) were compared to see if BMI changes correlated with changes in ectopia length. In addition, we compared and tested 154 recorded ectopia lengths from the patients (1 per patient) and patient BMI values with Pearson correlation and Welch t tests to determine if BMI changes either influenced or were associated with ectopia changes. RESULTS: For the 71 patients with multiple BMI values, change in ectopia length ranged from -4.6-9.8 mm but was not statistically significant (r = 0.019; P = 0.88). For the 154 measured ectopia lengths, changes in BMI did not correlate with ectopia length (P > 0.05). Likewise, differences in ectopia length between patients in normal, overweight, and obese categories were not statistically significant (|tstat| < |tcrit|, P > 0.05). CONCLUSIONS: In individual patients, we found that BMI and changes in BMI were not accompanied by changes in tonsil ectopia length.

Brachial Plexus Birth Injury: A Single-Center Study.

Infants can sustain traction injury to brachial plexus nerves during birth, called brachial plexus birth injury (BPBI). While spontaneous recovery is possible, upper extremity weakness can linger. We report our experience at a brachial plexus clinic from a retrospective chart review of infants with BPBI from September 2017 to September 2019. We determined Narakas Classification (NC) and Active Movement Scale (AMS) at predetermined follow-up points. Of 15 patients, 8 presented with NC-I, 5 with NC-II, and 2 with NC-III without Horner's syndrome. By 7 months, 3 had spontaneous recovery, and 4 achieved all and another 4 achieved most AMS5-7 scores. Eleven patients undergoing surgery had little-to-no improvement of shoulder abduction and shoulder external rotation AMS categories by 6 months. Our small sample size prevents us from making definitive conclusions but gave beneficial insight into our clinic barriers to follow-up, data collection, and collaboration with physical and occupational therapy.

Rhythmic mid-Temporal Theta of Drowsiness Activated by Hyperventilation- Uncommon Trigger of a Rare Benign EEG Variant in Pediatrics. An Educational Review.

Distinguishing abnormal electroencephalogram (EEG) waveforms from benign variants is critical for accurate interpretation of EEG. Hyperventilation (HV) is one of the basic procedures during EEG to enable activation of epileptiform activity. Rarely, HV can activate benign EEG rhythms. Herein, we illustrate two pediatric cases with bursts of rhythmic mid-temporal theta of drowsiness (RMTD), activated by hyperventilation. Continued awareness of this EEG phenomenology and its variations in pediatrics is important in avoiding misdiagnosis of epilepsy.

First documented clinical account of brachial plexus palsy from the 12th century.

OBJECTIVE: Although literary depiction of brachial plexus injury can be traced to Homer's Iliad, there is a scientific consensus that the first clinical description of brachial plexus palsy was not documented until the British physician Smellie reported it in the 18th century. However, the authors' recent review of the Syriac Book of Medicines (12th century) has uncovered a much earlier clinical documentation. METHODS: For this historical vignette, the authors reviewed the historical and anatomical literature regarding earlier descriptions of brachial plexus anatomy and pathology, including a thorough analysis of the Syriac Book of Medicines (attributed to an unknown Syriac physician in the Middle Ages) and Galen's On Anatomical Procedures and On the Usefulness of the Parts of the Body. RESULTS: Building on the galenic tradition with reference to independent dissections, the Syriac physician discussed nervous system anatomy and the clinical localization of neurological injuries. He described a patient who, after initial pulmonary symptoms, developed upper-extremity weakness more pronounced in the proximal muscles. His anatomical correlation placed the injury "where the nerves issue from the first and second muscles between the ribs" (scalene muscles), are "mixed," and "spread through many parts." The patient's presentation and recovery raise the possibility of Parsonage-Turner syndrome. The anatomical description of the brachial plexus is in line with Galen's earlier account and step-by-step surgical exposure, which the authors reviewed. They also examined Ibn Ilyas' drawing of the brachial plexus, which is believed to be a copy of the earliest artistic representation of the plexus. CONCLUSIONS: Whereas the Middle Ages were seen as a period of scientific stagnation from a Western perspective, Galen's teachings continued to thrive and develop in the East. Syriac physicians were professional translators, clinicians, and anatomists. There is evidence that brachial plexus palsy was documented in the Syriac Book of Medicines 6 centuries before Smellie.

Publications in Pediatric Epilepsy: Using Bibliometrics to Determine Readings in the Field.

Bibliometrics and citation analysis are popular forms of analyzing medical literature based on article impact as determined by the number of citations an article has received from other publications. Many bibliometric studies published within the past 10 years have assembled lists of highly cited papers, top 100 papers, or citation classics of specialties, subspecialties, and specific morbidities. For pediatric epilepsy, there is only 1 study that bibliometrically examines articles in this subspecialty. Although bibliometrics generally examines trends in the literature, we used bibliometrics as a methodology for determining a core set of pediatric epilepsy articles with the highest impact (ie, citation count) that could be used as an introductory reading list for residents, fellows, and early career epileptologists. Therefore, we searched Web of Science to identify the 100 top-cited pediatric epilepsy articles and develop 10 topic areas into which we sorted each article. These recommended articles could be used as essential readings for pediatric epilepsy.

Initial Real-World Experience With Cenobamate in Adolescents and Adults: A Single Center Experience.

BACKGROUND: Following approval by the US Food and Drug Administration (FDA) in late 2019, cenobamate (Xcopri) has been utilized to treat adults with focal seizures. Based on its robust efficacy from the phase 2 trials, we began using cenobamate in our adolescent and young adult patients whose seizures were not controlled with previously available options. This study expanded its real-world application to this cohort with focal epilepsy and a history of drug-related rash. METHODS: We conducted a retrospective study of our patients exposed to cenobamate (n = 45). We evaluated dosage and serum levels, efficacy, drug interactions, and adverse effects. RESULTS: After gradually increasing cenobamate to clinical effect using the FDA-approved dosing protocol, 60% (n = 22) of patients were responders. Adolescents were treated with an average daily dose of 204.0 mg, and adults with 223.4 mg cenobamate, and had serum levels of 20.5 µg/mL and 26.7 µg/mL, respectively. The side effect profile observed was similar to that seen in the phase 2/3 registry trials. Importantly, patients with a prior history of rash to other medications or antiseizure medications (n = 5) experienced no rashes related to cenobamate. CONCLUSIONS: This real-world study supports the findings of prior controlled studies regarding the efficacy of cenobamate as a treatment for focal seizures in adolescents and suggests that patients with a history of rash may benefit from this medication.

Bibliometric Analysis of Publications From 2011-2020 in 6 Major Neurosurgical Journals (Part 1): Geographic, Demographic, and Article Type Trends.

INTRODUCTION: Scientometrics is a subfield of bibliometrics that statistically analyzes publications trends. The aim of this initial study was to investigate trends in the 6 major neurosurgical journals from the last 10 years. METHODS: We searched Web of Science and Scopus for articles published in Neurosurgery, Journal of Neurosurgery, Journal of Neurosurgery: Spine, Journal of Neurosurgery: Pediatrics, Operative Neurosurgery, and World Neurosurgery from January 1, 2011, to December 31, 2020. Statistically analyzed parameters included national and continental distribution of articles, population density, density of neurosurgeons per 100,000 inhabitants, national per capita GDP, and national literacy rates. Bibliometric parameters assessed included total number of articles, H-indices, absolute/average number of citations per article, and article types. RESULTS: A total of 39,239 articles were published in the 6 journals. Journal of Neurosurgery and Neurosurgery had the strongest source impact. The most productive year was 2019 with 6811 published articles. Corresponding authors from the USA, China, Japan, Western Europe, and Turkey were the most productive. Articles published by authors from the USA received the majority of citations. Publication numbers increased in proportion with increases in country population, literacy rate, per capita GDP, and neurosurgeon density. The highest number of articles were published in 2016, and the fewest were published in 2020. CONCLUSIONS: Geographic trends in the diversity of neurosurgical publications sustained its steady increase in most developed counties. Simultaneously, the publication gap between developed and developing countries has remained stagnant.

Bibliometric Analysis of Major Neurosurgical Publications 2011-2020, Part 2: Journal, Author, Yearly Publication Trends, and Citation Related Metrics.

Background: Scientometrics, a subfield of bibliometrics, examines scientific publications by using bibliometric methods. The aim of a scientometric study is to study the various citation-based metrics of scientific articles, such as parameters pertaining to authors (including institutions and country of origin), articles, journals, and other citation related metrics. Objective: In this second part of our scientometric analysis of the 6 major neurosurgical journals from 2011-2020, we study journal and author trends, yearly publication trends, and citation related metrics in Neurosurgery, Journal of Neurosurgery, Journal of Neurosurgery: Spine, Journal of Neurosurgery: Pediatrics, Operative Neurosurgery, and World Neurosurgery. Methods: We analyzed parameters, including article and journal metrics (total articles published per journal per year, breakdown of the Bradford's law distribution of journals, and Lotka's law, journal impact factors), author metrics (country of origin, collaborations), citation totals, and keyword counts. Results and Discussion: The highest number of published articles from all journals occurred in 2011, the lowest in 2016. World Neurosurgery published the most. The author collaboration index has declined since 2016 with a notable drop in 2020 when the COVID-19 pandemic began. Impact factors remained stable, except for Operative Neurosurgery, which experienced a steep decline in 2020, and World Neurosurgery, which experienced a mild decline in 2020. Canadian authors were the most likely to participate in multi-country collaborations. Conclusion: The most articles were published in Journal of Neurosurgery, followed by Neurosurgery, Spine, and World Neurosurgery.

Legacy of Syriac-Aramaic Scholars in Transmitting Neurosurgical Knowledge Between Antiquity and the Middle Ages.

The link between ancient Greek medicine and the Arabic translation period in the 9th century cannot be understood without studying the contributions of Syriac scholars. With their mastery of Greek and the related Semitic languages of Syriac and Arabic, they initiated a scientific translation process with methods that prevail to this day. In this paper, we reviewed Hunayn Ibn Isshaq's Ten Treatises on the Eye to elucidate the original contributions of the Syriac physicians to the field of neurologic surgery. We analyzed the oldest known diagram of orbital anatomy along with Hunayn's genuine ideas on the optic nerve anatomy and pathology, optic chiasm, afferent pupillary reflex, and papilledema and venous congestion. We also reviewed the neurosurgical elements found in the Syriac Book of Medicines including the thought process in localizing neurologic deficits based on clinical experience and anatomic dissections and the earliest recorded description of brachial plexus pathology.

The 270° Circumferential Microsurgical Decompression of the Foramen Magnum in Adult Chiari Malformation Type I: Single Surgeon Series of 130 Patients with Syringomyelia, Neurologic, and Headache Outcomes.

OBJECTIVE: Chiari malformation type I (CM-I) is a craniocervical junction disorder associated with descent of the cerebellar tonsils >5 mm. The prevalence of CM-I is common, including 0.5%-3.5% in the general population, 0.56%-0.77% on magnetic resonance imaging, and 0.62% in anatomic dissection studies. We sought to measure our surgical outcomes related to resolution/improvement of headaches, neurologic outcomes, and syringomyelia compared with reported adult CM-I studies from 2000-2019. METHODS: From December 2003 to June 2018, the first author (K.I.A.) performed 270° circumferential decompression on adult (>18 years) patients with CM-I. At admission and follow-up, all parameters were numerically evaluated; headaches were self-reported on the visual analog scale, neurologic condition was evaluated using Karnofsky Performance Status and European Myelopathy Score, and syrinx width (if present) was measured on magnetic resonance imaging by grades I-IV. All parameters were analyzed, compared, and statistically tested. We compared results with our previously reported and updated systematic review of operative adult CM-I studies (studies from 2000 to 2019). RESULTS: In our series, 118/121 (98%) experienced headache improvements and 100% experienced neurologic improvements. Complete syrinx resolution was experienced by 35/43 (81%); 8 (19%) showed significant improvement. In data from reported studies (2000-2019), only 79% experienced headache resolution, 77% improvement of neurologic status, and 74% resolution/improvement of syrinx (mean). CONCLUSIONS: Our modified 270° circumferential microsurgical foramen magnum decompression for adult CM-I appears to be beneficial in improvement of outcomes, namely in resolution of the syrinx, neurologic symptoms, and headaches. We also confirm the association of body mass index with CM-I. Further studies are needed to confirm our results.