Clinical outcome after surgical management of spontaneous spinal epidural hematoma.

PURPOSE: Spontaneous spinal epidural hematoma (SSEH) is a rare pathology characterized by a hemorrhage in the spinal epidural space without prior surgical or interventional procedure. Recent literature reported contradictory findings regarding the clinical, radiological and surgical factors determining the outcome, hence the objective of this retrospective analysis was to re-assess these outcome-determining factors. METHODS: Patients surgically treated for SSEH at our institution from 2010 - 2022 were screened and retrospectively assessed regarding management including the time-to-treatment, the pre-and post-treatment clinical status, the radiological findings as well as other patient-specific parameters. The outcome was assessed using the modified McCormick Scale. Statistical analyses included binary logistic regression and Fisher's exact test. RESULTS: In total, 26 patients (17 men [65%], 9 women [35%], median age 70 years [interquartile range 26.5]) were included for analysis. The SSEHs were located cervically in 31%, cervicothoracically in 42% and thoracically in 27%. Twenty-four patients (92%) improved after surgery. Fifteen patients (58%) had a postoperative modified McCormick Scale grade of I (no residual symptoms) and 8 patients (31%) had a grade of II (mild symptoms). Only 3 (12%) patients remained with a modified McCormick Scale grade of IV or V (severe motor deficits / paraplegic). Neither time-to-treatment, craniocaudal hematoma expansion, axial hematoma occupation of the spinal canal, anticoagulation or antiplatelet drugs, nor the preoperative clinical status were significantly associated with the patients' outcomes. CONCLUSION: Early surgical evacuation of SSEH generally leads to favorable clinical outcomes. Surgical hematoma evacuation should be indicated in all patients with symptomatic SSEH.

Moyamoya Disease: Advances in Diagnosis, Treatment, and Surgical Interventions.

Moyamoya disease (MMD) is a rare cerebrovascular disorder characterized by progressive narrowing of the brain's arteries, leading to an increased risk of stroke. The primary susceptibility gene, RNF213, has been identified in individuals of East Asian descent, contributing to ongoing research into potential therapeutic targets. The distinction between idiopathic MMD and secondary forms, such as Moyamoya syndrome (MMS), is discussed, focusing on associated conditions and risk factors. Surgical revascularization emerges as the mainstay of treatment, with direct, indirect, and combination bypass procedures explored. The review delves into advancements in imaging technology for diagnosis and treatment planning, emphasizing non-invasive magnetic resonance examination's role in identifying asymptomatic patients. Additionally, insights into anesthetic care and therapeutic approaches underscore the evolving understanding of this complex disease. The presented information aims to contribute to the ongoing dialogue surrounding MMD, providing a valuable resource for clinicians and researchers.

"The novel dura substitute: a revolutionary advancement in neurosurgery".

This Article provides a concise summary of the comprehensive exploration into the dura mater, dural tears, and the groundbreaking medical device, ArtiFascia® Dura Substitute. The neuroanatomy of the dura mater is elucidated, emphasizing its resilience and susceptibility to tears during spinal surgery. Dural repair methods are scrutinized, with research findings revealing the efficacy of primary closure with or without a patch.The introduction of ArtiFascia®, a nanofiber-based resorbable dural repair graft, represents a pivotal moment in neurosurgery. Obtaining 510(k) clearance from the FDA, ArtiFascia® demonstrates exceptional biological benefits, including enhanced cellular adhesion and tissue regeneration. The device's safety is affirmed through chemical analysis and toxicological risk assessment.The NEOART study, a randomized clinical trial involving 85 subjects across prominent European medical centers, validates ArtiFascia®'s superiority over existing dural substitutes. Noteworthy findings include exceptional graft strength, durability, and its ability to withstand physiological pressures.In conclusion, ArtiFascia® marks a revolutionary era in neurosurgery, promising safer and more effective solutions. This innovative device has the potential to elevate standards of care, offering both patients and surgeons an improved experience in navigating the complexities of neurosurgical procedures. The abstract encapsulates the key elements of the research, emphasizing the transformative impact of ArtiFascia® in the field.

Evaluating the efficacy of standardized pressure ulcer management protocols in the prevention of pressure injuries among patients undergoing neurosurgical procedures.

Pressure injuries are a significant concern for patients undergoing neurosurgical procedures due to prolonged immobility and the complexity of care. This study evaluates the efficacy of standardized pressure ulcer management protocols in preventing pressure injuries and enhancing patient care in a neurosurgical context. A comprehensive retrospective analysis was conducted at a single institution from December 2020 to December 2023, comparing 50 patients who received standardized pressure ulcer management (intervention group) with 50 patients who received conventional care (control group). The study assessed the incidence of pressure ulcers, patient comfort levels using the Kolcaba Comfort Scale and sleep quality using the Richards-Campbell Sleep Questionnaire (RCSQ). Statistical analysis was performed using SPSS software, version 27.0, applying t-tests and chi-square tests as appropriate. The intervention group exhibited a significantly lower incidence of pressure ulcers at all measured time points post-surgery compared to the control group. Patient comfort levels in the intervention group were consistently higher across psychological, environmental, physiological and socio-cultural domains. Sleep quality metrics, including sleep depth, latency to sleep onset and overall sleep quality, were significantly improved in the intervention group. The implementation of standardized pressure ulcer management protocols in neurosurgical care significantly reduces the incidence of pressure injuries, enhances patient comfort and improves sleep quality. These findings highlight the importance of adopting structured care protocols to improve postoperative outcomes and patient well-being in neurosurgical settings.

Medical History and Preoperative Coagulation Profile as Predictors of Outcomes in Elective Spinal Surgery: A Meta-Analysis.

BACKGROUND: In patients with unremarkable medical history, comprehensive preoperative hemostasis screening in elective neurosurgery remains debated. Comprehensive medical history has shown to be noninferior to coagulation profile to evaluate surgical outcomes. This study aims to evaluate the predictiveness of preoperative coagulation screening and medical history for surgical outcomes. METHODS: Databases were searched until April 2023 for observational cohort studies that reported preoperative hemostasis screening and clinical history prior to elective neurosurgical procedures. Outcomes of interest included postoperative transfusion, mortality, and complications. Pooled relative risk ratios (RRs) were analyzed using random-effects models. RESULTS: Out of 604 studies, 3 cohort studies met our inclusion criteria, adding a patient population of 83,076. Prolonged partial thromboplastin time (PTT; RR=1.42, 95% confidence interval [CI] =1.14, 1.77, P=0.002), elevated international normalized ratio (INR; RR=2.01, 95% CI=1.14, 3.55, P=0.02), low platelet count (RR=1.58, 95% CI=1.34, 1.86, P<0.00001), and positive bleeding history (RR=2.14, 95% CI=1.16, 3.93, P=0.01) were associated with postoperative transfusion risk. High PTT (RR=2.42, 95% CI=1.24, 4.73, P=0.010), High INR (RR=8.15, 95% CI=5.97, 11.13; P<0.00001), low platelet count (RR=4.89, 95% CI=3.73, 6.41, P<0.00001), and bleeding history (RR=7.59, 95% CI=5.84, 9.86, P<0.00001) were predictive of mortality. Prolonged PTT (RR=1.53, 95% CI=1.25, 1.86, P=<0.0001), a high INR (RR=3.41, 95% CI=2.63, 4.42, P=< 0.00001), low platelets (RR=1.63, 95% CI=1.40, 1.90, P=<0.00001), and medical history (RR=2.15, 95% CI=1.71, 2.71, P=<0.00001) were predictive of complications. CONCLUSIONS: Medical history was a noninferior predictor to coagulation profile for postoperative transfusion, mortality, and complications. However, our findings are mostly representative of elective spinal procedures. Cost-effective alternatives should be explored to promote affordable patient care in patients with unremarkable history.

Training Cerebrovascular and Neuroendovascular Surgery Residents: A Systematic Literature Review and Recommendations.

Background: The rapid evolution of neuroendovascular intervention has resulted in the inclusion of endovascular techniques as a core competency in neurosurgical residency training. Methods: We conducted a literature review of studies involving the training of neurosurgical residents in cerebrovascular and endovascular neurosurgery. We reviewed the evolution of cerebrovascular neurosurgery and the effects of these changes on residency, and we propose interventions to supplement contemporary training. Results: A total of 48 studies were included for full review. Studies evaluated trainee education and competency (29.2%, 14/48), neuroendovascular training models (20.8%, 10/48), and open cerebrovascular training models (52.1%, 25/48), with some overlap. We used a qualitative analysis of reviewed reports to generate a series of suggested training supplements to optimize cerebrovascular education. Conclusion: Cerebrovascular neurosurgery is at a crossroads where trainees must develop disparate skill sets with inverse trends in volume. Continued longitudinal exposure to both endovascular and open cerebrovascular surgical fields should be mandated in general resident education, and blended learning tactics using adjunct simulation systems and models should be incorporated with didactics to both optimize learning and alleviate restraints placed by decreased volume and autonomy.

Use of Clamp-Like Devices to Fix Bifrontal Basal Craniotomies: Three Case Reports.

The three case reports presented here provide clinical evidence of a configuration to easily and successfully fix bifrontal basal craniotomies with a clamp-like fixation device (Cranial LOOP™, NEOS Surgery, Barcelona, Spain): A 72-year-old woman undergoing resection of a meningioma at the sphenoidal level, a 43-year-old man undergoing clipping of an anterior communicating artery aneurism, and a 55-year-old woman undergoing macroscopical resection of a meningioma on the olfactory groove had their surgery performed through a bifrontal basal craniotomy, and, once the intervention was completed, the fixation of the cranial flap was performed using Cranial LOOP™, with a configuration consisting of two Cranial LOOP™ L at the basal lateral level and two additional products at the posterior frontal level. The result of this fixation was very satisfactory with no settling or artifacts during the follow-up. These cases show that Cranial LOOP™ can be used to fixate bifrontal basal craniotomies.

Anaesthesia Management for Neurosurgery in a Patient With Congenital Lung Agenesis.

Congenital lung agenesis is a rare congenital abnormality associated with an absence or under-development of either one or both lungs, and its presentation in adulthood is even rarer. We describe a 40-year-old female patient with a history of congenital agenesis of the right lung and a high-grade glioma in the frontal region of the brain presenting for craniotomy and excision of the tumor in an MRI suite. Lung protective strategies of ventilation were utilized intraoperatively. The remote location of the MRI suite made access to extra manpower support challenging. The patient was managed uneventfully and discharged stable to the high-dependency unit. Our case describes how congenital lung agenesis poses a unique set of challenges for anaesthetic management, particularly in neurosurgical patients, and provides guidance to a multidisciplinary team approach.

Clipping of a persistent middle cerebral artery aneurysm after previous flow diverter placement: An illustrative case and review of the literature.

Flow diverter (FD) is increasingly used in the management of wide necked cerebral aneurysms. Despite a reported lower efficacy in middle cerebral artery (MCA) aneurysms, they are still being utilised. Microsurgery is best considered as an index treatment, but can also be a safe and effective treatment when encountering a persistent MCA aneurysm after prior FD. As there is a paucity in literature and more cases of failed FD are expected to appear, we want to add our experience to the existing literature. The microsurgical management of a persistent MCA bifurcation aneurysm, 3 years after a p48 MW HPC Flow Diverter (phenox GmbH, Bochum Germany) insertion is reported and the relevant literature discussed.

Effectiveness of subtemporal decompression for the management of slit ventricle syndrome.

OBJECTIVES: To assess the effectiveness of subtemporal decompression in the management of slit ventricle syndrome. METHODS: We conducted a retrospective review of all patients with slit ventricle syndrome (SVS) who underwent subtemporal decompression (STD) at our centre between 2010 and 2021. Cases were identified using the hospital database. Medical records for each patient were reviewed, including operative and radiological reports. RESULTS: Fifteen patients underwent STD for the management of SVS. Median age at time of STD was 9.18 years. Aetiology of hydrocephalus consisted of spinal dysraphism (5), idiopathic (4), post-infectious (1), post-haemorrhagic (3), secondary to tumour (1), and craniofacial anomalies (1). Median age at first shunt insertion was 3.4 months. Median pre-operative period assessed, from initial shunt insertion to STD, was 4.54 (interquartile range [IQR] 3.12-10.47) years. Twelve patients underwent ≥1 shunt revision prior to STD. All patients had a diagnosis of SVS at time of STD. Presenting symptoms, for the admission in which STD was performed, included nausea (9), vomiting (8), lethargy (8), headache (12), irritability (5), and visual disturbances (6). One third underwent shunt revision at the time of STD. Two patients developed post-operative complications requiring further surgery (meningitis requiring shunt revision: 1; wound debridement: 1). Three patients developed uncomplicated post-operative pyrexia, which was managed with antibiotics. Median duration of post-operative follow-up was 5.4 (IQR 1.73-8.54) years. Eleven patients underwent ≥1 shunt related procedure following STD. Wilcoxon signed-rank test demonstrated a significant difference in number of shunt related procedures before (median = 5, IQR 1-8) and after (median = 3, IQR 0-5) STD (Z = -2.083, p = .037). All patients reported subjective symptom improvement post-operatively. Thirteen patients experienced symptom recurrence at a median duration of 10 months post-operatively. CONCLUSIONS: STD was associated with a reduction in the amount of shunt related procedures required in this group of patients with SVS. Further study is required to confirm this association.

The impact of intraoperative N-acetylcysteine on opioid consumption following spine surgery: a randomized pilot trial.

Aim: N-acetylcysteine (NAC) decreases inflammation and could augment perioperative analgesia. Materials & methods: This prospective pilot trial examined postoperative opioid consumption at 12 h following intraoperative NAC. In phase I, 20 adults scheduled for posterior spine surgery were randomized to NAC (0, 50, 100 and 150 mg/kg) to determine the optimal dose. In phase II, 30 patients were randomized to placebo or NAC (150 mg/kg). Opioid consumption, pain ratings and time to opioid rescue were recorded. Results: Postoperative opioid consumption was reduced in the NAC group 19.3% at 12 h and 20% at 18 and 36 h. Opioid consumption was reduced 22-24% in the NAC group at all times after adjusting for intraoperative opioid administration. NAC subjects reported lower pain scores relative to placebo. Conclusion: Subjects randomized to NAC consumed less postoperative opioids and reported less pain versus placebo. Larger randomized controlled trials are needed to further evaluate NAC for analgesia. Clinical Trial Registration: NCT04562597 (ClinicalTrials.gov).

N-acetylcysteine (NAC) is a powerful anti-inflammatory drug used to treat some types of poisoning. It could help pain for patients after surgery. This study looked at how much pain medicine patients needed after back surgery when they received NAC or no drug (placebo). In the first 20 patients, people randomly received placebo or a small, medium or large dose of NAC (0, 50, 100, and 150 mg/kg) with five patients in each group. Since there were only a small number of patients, it was difficult to see any definite differences, and the next 30 patient patients randomly received placebo or the large dose of NAC (150 mg/kg). Patients that were given NAC received 16­22% less opioids in the first 2 days after surgery compared with those that were given placebo. NAC patients also took longer to request pain medications after surgery and reported lower pain scores in the first 2 days after surgery relative to placebo.

Management Paradigm of Central Nervous System Metastases in NSCLC: An Australian Perspective.

Life-prolonging central nervous system active systemic therapies for metastatic NSCLC have increased the complexity of managing brain metastases (BMs). Australian medical oncologists, radiation oncologists, and neurosurgeons discussed the evidence guiding the diverse clinical approaches to the management of BM in NSCLC. The Australian context is broadly applicable to other jurisdictions; therefore, we have documented these discussions as principles with broader applications. Patient management was stratified according to clinical and radiologic factors under two broad classifications of newly diagnosed BMs: symptomatic and asymptomatic. Other important considerations include the number and location of metastases, tumor histotypes, molecular subtype, and treatment purpose. Careful consideration of the pace and burden of symptoms, risk of worsening neurologic function at a short interval, and extracranial disease burden should determine whether central nervous system active systemic therapies are used alone or in combination with local therapies (surgery with or without radiation therapy). Most clinical trial evidence currently focuses on historical treatment options or a single treatment modality rather than the optimal sequencing of multiple modern therapies; therefore, an individualized approach is key in a rapidly changing therapeutic landscape.

Predictors of Prolonged Length of Stay After Pituitary Adenoma Resection: A Large Cohort Analysis Using the National Inpatient Sample (2016-2019).

OBJECTIVE: In this nationwide retrospective study, the authors aimed to identify demographic, clinical, and baseline health risk factors predictive of a prolonged length of stay (PLOS) for patients with pituitary adenomas (PAs). METHODS: The National Inpatient Sample dataset from 2016 to 2019 was utilized to identify all included hospitalizations for PA resection as identified by the appropriate diagnosis-related group code. Comorbidities were classified based on the Charlson Comorbidity Index mapping of ICD-10 codes, and PLOS was identified as any stay longer than 3 days. Univariable and multivariable logistic regression models, accounting for the sample design, were built to determine factors associated with PLOS and emergent surgery. RESULTS: Overall, 30 945 patients were included in this study with 10 535 patients having PLOS. Female patients experienced an increased odds of PLOS (odds ratio [OR]: 1.29; P < .001). Black patients (OR: 1.49; P < .001) and Hispanic patients (OR: 1.30; P = .003) had 1.49 times and 1.30 times the odds of PLOS compared to White patients, respectively. Compared to patients insured by Medicare, patients insured by Medicaid had an increased odds of PLOS (OR: 1.36; P = .007) as well as emergent surgery (OR: 5.40; P < .001). When stratified by emergent surgeries, Black patients (OR: 1.89; P < .001), Hispanic patients, (OR: 2.14; P < .001), and patients on Medicaid insurance (OR: 1.71; P < .001) were at an increased risk of emergent procedures. However, female sex (OR: 0.65; P < .001), upper third quartile (OR: 0.73; P = .017), and fourth quartile (OR: 0.69; P = .014) of patients categorized by zip code income were at decreased odds of an emergent procedure. CONCLUSIONS: Black and Hispanic patients, patients with Medicaid insurance, and patients of low socioeconomic status patients are at significantly higher risk of emergent PA resection and PLOS. Efforts to prevent emergent surgeries and shorten hospitalization after pituitary surgery may need to primarily focus on patient groups with select sociodemographic characteristics.

Improving patient safety during position changes under general anaesthesia: "CHOPP check"- a new patient safety and educational tool.

The requirement to change position whilst under general anaesthesia may expose patients to significant risks. We devised and implemented a concise and comprehensive patient positioning safety tool with the aim of reducing risks and improving patient safety during position changes under anaesthesia.

Worldwide Research Trends on Transvenous Embolization of Brain Arteriovenous Malformations: A Bibliometric and Visualized Study.

BACKGROUND: Transvenous embolization (TVE) of brain arteriovenous malformations (bAVMs) is an emerging endovascular technique that has shown high cure rates in selected cases. The rationale of our study was to determine authorship and worldwide institutional trends and contributions to the knowledge in this topic. METHODS: Web of Science database was used. A total of 63 articles were included based on predefined inclusion criteria, which were manually reviewed. The bibliometric analysis involved the use of quantitative bibliometric indicators and network analysis with co-authorship and co-occurrence of terms, which were performed using the bibliometrix package in R and VOSviewer, respectively. RESULTS: The first article was published in 2010, with the largest number of articles published in 2022 (10 articles). The average number of citations per document was 11.38, and the annual growth rate was 14.35%. The top 10 authors with the most scientific production on TVE of bAVMs were from France, and the most cited study was published by Iosif C in 2015, followed by Consoli A in 2013, and Chen CJ in 2018. Journal of Neurointerventional Surgery was the journal with the most articles published. The most commonly used keywords were dural arteriovenous fistula, Onyx, vascular disorders, and neurological surgery around 2016, and intervention around 2021. CONCLUSIONS: TVE of bAVMs is an emerging technique. Our search identified some scientific articles, without randomized clinical trials, but many case series from single institutions. French and German institutions are the pioneers in the field, and further research is required in specialized endovascular centers.

Data Quality Estimation Via Model Performance: Machine Learning as a Validation Tool.

In our recent study, the attempt to classify neurosurgical operative reports into routinely used expert-derived classes exhibited an F-score not exceeding 0.74. This study aimed to test how improving the classifier (target variable) affected the short text classification with deep learning on real-world data. We redesigned the target variable based on three strict principles when applicable: pathology, localization, and manipulation type. The deep learning significantly improved with the best result of operative report classification into 13 classes (accuracy = 0.995, F1 = 0.990). Reasonable text classification with machine learning should be a two-way process: the model performance must be ensured by the unambiguous textual representation reflected in corresponding target variables. At the same time, the validity of human-generated codification can be inspected via machine learning.

Bone Morphogenic Protein and Mesenchymal Stem Cells to Regenerate Bone in Calvarial Defects: A Systematic Review.

BACKGROUND: The use of bone morphogenic protein and mesenchymal stem cells has shown promise in promoting bone regeneration in calvarial defects. However, a systematic review of the available literature is needed to evaluate the efficacy of this approach. METHODS: We comprehensively searched electronic databases using MeSH terms related to skull defects, bone marrow mesenchymal stem cells, and bone morphogenic proteins. Eligible studies included animal studies that used BMP therapy and mesenchymal stem cells to promote bone regeneration in calvarial defects. Reviews, conference articles, book chapters, and non-English language studies were excluded. Two independent investigators conducted the search and data extraction. RESULTS: Twenty-three studies published between 2010 and 2022 met our inclusion criteria after a full-text review of the forty-five records found in the search. Eight of the 23 studies used mice as models, while 15 used rats. The most common mesenchymal stem cell was bone marrow-derived, followed by adipose-derived. BMP-2 was the most popular. Stem cells were embedded in Scaffold (13), Transduction (7), and Transfection (3), and they were delivered BMP to cells. Each treatment used 2 × 104-1 × 107 mesenchymal stem cells, averaging 2.26 × 106. Most BMP-transduced MSC studies used lentivirus. CONCLUSIONS: This systematic review examined BMP and MSC synergy in biomaterial scaffolds or alone. BMP therapy and mesenchymal stem cells in calvarial defects, alone, or with a scaffold regenerated bone. This method treats skull defects in clinical trials. The best scaffold material, therapeutic dosage, administration method, and long-term side effects need further study.

Neurovascular Structures at Risk During Surgical Access to Trigeminal Ganglion and Meckel's Cave - An Anatomical Study.

Background: It is difficult to approach the Trigeminal Ganglion (TG) and Meckel's cave (MC) during surgeries. Therefore, the exact knowledge of the relationship of surgical landmarks to related anatomical structures is vital to reduce the associated postoperative morbidity. The aim of the present study was to enhance the knowledge of the surgical anatomy of structures that are present in the conduit of all surgical approaches to TG and MC, their distances from surrounding neurovascular structures, and their variations. Material and Methods: The study was carried out on 40 embalmed cadavers (Eight Female) of the anatomy department of a teaching hospital in Central India. Meticulous dissection of cranial fossae was done to locate TG, MC, and related anatomical structures. All distances from TG and MC were measured using an electronic digital calliper. Results: Length, width, and thickness of TG were 15.39 mm, 4.39 mm, and 2.54 mm, respectively. The distance from zygomatic arch, the lateral end of the petrous ridge, arcuate eminence, foramen ovale, and foramen spinosum to MC was 26.10 mm and 37.94 mm, 16.46 mm, 4.54 mm, and 11.23 mm, respectively. The sixth, fourth, and third cranial nerves were 6.26 mm, 4.94 mm, and 2.53 mm from MC, respectively. The MC was 42.72 mm and 33.87 mm anteromedial from posterior and anterior limits of the sigmoid sinus. Conclusion: Findings of the present study will aid surgical planning and decide the approach to TG and MC and avoid surgical complications.

Global Research Trends of Neurosurgery: A Comprehensive Bibliometric and Visualized Analysis of Systematic Reviews.

OBJECTIVE: This study aimed to determine the bibliometric characteristics of scientific articles on systematic reviews of neurosurgery worldwide. METHODS: Bibliographic searches were performed in journals indexed by the Web of Science database until 2022, with no language restrictions. A total of 771 articles were ultimately included on the basis of predefined inclusion criteria, which were manually reviewed. The bibliometric analysis involved the use of quantitative bibliometric indicators and network analysis, which were performed using the bibliometrix package in R and VOSviewer, respectively. RESULTS: The first publication was in 2002, and the number of publications increased over time, with the largest number of publications in 2021 (156 articles). The average number of citations per document was 17.36, and the annual growth rate was 6.82%. Nathan A. Shlobin was the author with the most published articles (19 articles). The most cited study was published by Jobst BC (2015). WORLD NEUROSURGERY was the journal with the most publications (51 articles). The country of corresponding authors with the most publications and the greatest number of total citations was the United States. The affiliations with the most articles were University of Toronto (67 articles) and Harvard Medical School (54 articles). CONCLUSIONS: The increasing trend during the past 20 years, and especially in the past 2 years, highlights the advancements in various subspecialities in the field. Our analysis revealed that North American and Western European countries are at the forefront of the field. There is a poor output of publications, authors, and affiliations in Latin-American and African countries.