Flow Diversion for Treatment of Anterior Inferior Cerebellar Artery Aneurysms: Mechanism and Pitfalls from a Novel Management Strategy.

BACKGROUND: Anterior inferior cerebellar artery (AICA) aneurysms present a challenge for neurosurgeons and neurointerventionalists alike. METHODS: Cases of AICA aneurysms managed with endovascular flow diversion at our institute are reviewed with their angiographic outcomes. RESULTS: Both direct and indirect flow diversion provide complete aneurysm occlusion at follow-up. We propose a stratified method of approaching AICA aneurysms based on location, rupture status, and neck size. CONCLUSIONS: Careful evaluation of preoperative parameters is paramount in deciding between a surgical or a neuroendovascular approach. Low-profile stents in the future may assist in direct flow diversion of AICA trunk aneurysms. In addition, neurosurgeons need to be well versed in endovascular approaches.

Impact of Gap Years Following Medical School Graduation on Resident Research Productivity in Ophthalmology.

Background Gap years following medical school graduation have become more common, but research into their tangible career benefit is lacking. Examining the impact of gap years on resident scholarly productivity in ophthalmology may provide insight generalizable to all specialties. Objective To evaluate whether a gap year following medical school graduation significantly predicts scholarly productivity during ophthalmology residency. Methods In December 2021, residents were recorded from 110 publicly available American ophthalmology residency program webpages. They were included if educational history was listed on publicly accessible academic and social media profiles. Residents were then stratified into gap year and nongap year cohorts. Publication data were recorded from Scopus and PubMed. Pearson's chi-square, independent sample t -tests, and multivariable regression were performed. Results A total of 1,206 residents were analyzed, with 1,036 (85.9%) residents taking no gap year and 170 (14.1%) residents with at least one gap year. Gap year residents were predicted to have increase in the likelihoods of publishing at least one, two, or five total articles during residency, in addition to at least one article in a high-impact journal. There was no significant relationship between gap years and publications with senior authors affiliated with either the resident's medical school or residency program. Conclusion Residents taking gap years following graduation may publish more during residency, but these publications are not associated with senior authors at their institutions. Future investigations should continue to evaluate the significance of gap years in medical education.

Network analysis of neurosurgical literature: an increased focus on training during the COVID-19 pandemic.

The COVID-19 pandemic led to stringent guidelines to restrict the conduct of non-emergent surgical procedures. Consequently, neurosurgery departments experienced a decline in case volumes and greater educational time being spent on virtual research projects. In our report, we reveal how neurosurgical research has changed during the pandemic compared to the pre-pandemic phase. The WebOfScience database was searched for neurosurgical articles published between 2012-2019 (pre-pandemic) and 2020-2022 (pandemic). From this data, the keywords, terms, and countries were analyzed using networks formed by the VOS Viewer software. In addition, the analysis was repeated for neurosurgical articles specific to COVID-19. Network analyses of terms and keywords revealed an increased popularity of virtual research projects, including case reports, meta-analyses, reviews, surveys, and database studies. Additionally, there was increased interest in research pertaining to neurosurgical education during the post-pandemic era, including topics regarding virtual training modalities, mental health, and telemedicine. Our bibliometrics analysis suggests that the impact of COVID-19 restrictions on hospital systems affected neurosurgical training programs. Future investigations should explore the effects of the trainee experience during the COVID-19 pandemic on the outlook for neurosurgical education.

Applying Shear Wave and Magnetic Resonance Elastography to Grade Brain Tumors: Systematic Review and Meta-Analysis.

BACKGROUND: Reports find that magnetic resonance elastography (MRE) and shear wave elastography (SWE) can classify intracranial tumors according to stiffness. However, systematic syntheses of these articles are lacking. In this report, a systematic review and meta-analysis was performed to evaluate whether SWE and MRE can predict meningioma and glioma grades. METHODS: PubMed and Scopus were searched between February 10, 2022. and March 2, 2022. using manual search criteria. Eight out of 106 non-duplicate records were included, encompassing 84 patients with low-grade tumors (age 42 ± 13 years, 71% female) and 92 patients with high-grade tumors (age 50 ± 13 years, 42% female). Standardized mean difference in stiffness between high-grade and low-grade tumors were measured using a forest plot. The I2, χ2, and t tests were performed, and bubble plots were constructed to measure heterogeneity. An adapted QUADAS-2 scale evaluated study quality. Additionally, a funnel plot was constructed, and an Egger's intercept test determined study bias. RESULTS: Low-grade tumors were stiffer than high-grade tumors (Cohen's D = -1.25; 95% CI -1.88, -0.62). Moderate heterogeneity was observed (I2 = 67%; P = 0.006) but controlling for publication year (I2 = 0.2%) and age (I2 = 0.0%-17%) reduced heterogeneity. Included studies revealed unclear or high bias for the reference standard and flow and timing (>50%). CONCLUSIONS: Elastography techniques have potential to grade tumors intraoperatively and postoperatively. More studies are needed to evaluate the clinical utility of these technologies.

Trends in Global Research for Treating Intracranial Aneurysms: A Bibliometric Analysis.

OBJECTIVE: Although significant advancements have been made in the detection, surveillance, and treatment of intracranial aneurysms, research and care can differ vastly based on location. Currently, there is lack of knowledge regarding the trends in literature and how the field is evolving with new technology. Here, we use bibliometric analysis to visualize the knowledge structure of the field and identify global research trends in intracranial aneurysm treatment. METHODS: The Web of Science Core Collection was queried for primary research and review articles related to intracranial aneurysm treatment. Four thousand seven hundred and 2 relevant documents were collected and publications over time on different treatment types and publications and citations of journals were collected. VOS viewer was used for the following: 1) identify relationships between keywords, 2) identify co-authorship patterns among organizations and countries, and 3) analyze citation patterns of countries, organizations, and journals. RESULTS: Our results show that research in flow diversion increased at a rapid rate but tended to have low link strength with keywords related to evaluating patient risk and mortality. The highest publication producing countries were the United States of America, Japan, and China, although China had fewer citations relative to its peers. Korean organizations showed less international collaboration. The USA has been the leader in terms of productivity and collaboration in the field, as have several US-based journals such as Journal of Neurosurgery, Neurosurgery, and World Neurosurgery. CONCLUSIONS: Evaluating the safety of flow diversion treatment remains a pressing area of research. Chinese and Korean organizations may be of interest for global collaborations.

Female authorship trends and the effect of COVID-19 on cataract and refractive surgery literature.

PURPOSE: To evaluate whether gender barriers persist specifically in the cataract and refractive surgery (CRS) literature. In addition, no literature exists investigating the long-term effect of COVID-19 on female authorship in ophthalmology past 2020. SETTING: Scopus 2015 to 2022. DESIGN: Retrospective data review. METHODS: Articles published in the Journal of Refractive Surgery and the Journal of Cataract & Refractive Surgery were recorded from January 2015 to February 2022 from Scopus. Articles with only 1 author or where gender could not be identified were excluded. The first author (FA) gender, senior author (SA) gender, affiliated country, type of literature, and number of citations were collected. Pearson chi-squared tests with phi coefficients and multivariate logistic regression were performed. RESULTS: 3153 articles were included in analysis. There were 910 works with female FAs and 648 with female SAs. Gender did not predict publishing in one journal over the other (P > .050). Women made up less than 30% of authorship of all types of literature, except for prospective/observational studies as FA (31.3%). Compared with before 2020, female FAs from 2020 onward were associated with increased retrospective analysis (phi = 0.072, P = .030) and letters/editorials (phi = 0.134, P < .001) but decreased case reports (phi = 0.087, P = .009) and "others" (phi = -0.164, P < .001). Similar associations were observed for female SAs. Females were more likely to publish in Asian countries. Female SAs predicted an increased likelihood of female FAs (odds ratio, 1.401, 95% CI, 1.165-1.684, P < .001). CONCLUSIONS: Gender disparities exist in authorship of the CRS literature. COVID-19 has altered the types of literature published by women, but men still publish most of all types of CRS research.

Do overlapping neurosurgical procedures affect patient outcomes? A systematic review and meta-analysis.

Overlapping surgery (OS) is a common practice in neurosurgery that has recently come under scrutiny. This study includes a systematic review and meta-analysis on articles evaluating the effects of OS on patient outcomes. PubMed and Scopus were searched for studies that analyzed outcome differences between overlapping and non-overlapping neurosurgical procedures. Study characteristics were extracted, and random-effects meta-analyses were performed to analyze the primary outcome (mortality) and secondary outcomes (complications, 30-day readmissions, 30-day operating room returns, home discharge, blood loss, and length of stay). Mantel-Haenszel tests were completed for binary outcomes, whereas the inverse variance tests were conducted for continuous outcomes. Heterogeneity was measured using the I2 and X2 tests. The Egger's test was conducted to evaluate publication bias. Eight of 61 non-duplicate studies were included. Overall, 21,249 patients underwent non-OS (10,504 female) and 15,863 patients underwent OS (8393 female). OS was associated with decreased mortality (p = 0.002), 30-day returns to OR (p < 0.001), and blood loss (p < 0.001) along with increased home discharges (p < 0.001). High heterogeneity was observed for home discharge (p = 0.002) and length of stay (p < 0.001). No publication bias was observed. OS was not associated with worse patient outcomes compared to non-OS. However, considering multiple sources of limitation in the methodology of the included studies (such as limited number of studies, reports originating from mostly high-volume academic centers, discrepancy in the definition of "critical portion(s)" of the surgery across studies, and selection bias), extra caution is advised in interpretation of our results and further focused studies are warranted.

Glutamate Receptors Mediate Changes to Dendritic Mitochondria in Neurons Grown on Stiff Substrates.

The stiffness of brain tissue changes during development and disease. These changes can affect neuronal morphology, specifically dendritic arborization. We previously reported that N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors regulate dendrite number and branching in a manner that is dependent on substrate stiffness. Since mitochondria affect the shape of dendrites, in this study, we determined whether the stiffness of substrates on which rat hippocampal neurons are grown affects mitochondrial characteristics and if glutamate receptors mediate the effects of substrate stiffness. Dendritic mitochondria are small, short, simple, and scarce in neurons cultured on substrates of 0.5 kPa stiffness. In contrast, dendritic mitochondria are large, long, complex, and low in number in neurons grown on substrates of 4 kPa stiffness. Dendritic mitochondria of neurons cultured on glass are high in number and small with complex shapes. Treatment of neurons grown on the stiffer gels or glass with the NMDA and AMPA receptor antagonists, 2-amino-5-phosphonopentanoic acid and 6-cyano-7-nitroquinoxaline-2,3-dione, respectively, results in mitochondrial characteristics of neurons grown on the softer substrate. These results suggest that glutamate receptors play important roles in regulating both mitochondrial morphology and dendritic arborization in response to substrate stiffness.