Transcriptional expression changes during compensatory plasticity in the terminal ganglion of the adult cricket Gryllus bimaculatus.

BACKGROUND: Damage to the adult central nervous system often leads to long-term disruptions in function due to the limited capacity for neurological recovery. The central nervous system of the Mediterranean field cricket, Gryllus bimaculatus, shows an unusual capacity for compensatory plasticity, most obviously in the auditory system and the cercal escape system. In both systems, unilateral sensory disruption leads the central circuitry to compensate by forming and/or strengthening connections with the contralateral sensory organ. While this compensatory plasticity in the auditory system relies on robust dendritic sprouting and novel synapse formation, the compensatory plasticity in the cercal escape circuitry shows little obvious dendritic sprouting and instead may rely on shifts in excitatory and inhibitory synaptic strength. RESULTS: In order to better understand what types of molecular pathways might underlie this compensatory shift in the cercal system, we used a multiple k-mer approach to assemble a terminal ganglion transcriptome that included ganglia collected one, three, and 7 days after unilateral cercal ablation in adult, male animals. We performed differential expression analysis using EdgeR and DESeq2 and examined Gene Ontologies to identify candidates potentially involved in this plasticity. Enriched GO terms included those related to the ubiquitin-proteosome protein degradation system, chromatin-mediated transcriptional pathways, and the GTPase-related signaling system. CONCLUSION: Further exploration of these GO terms will provide a clearer picture of the processes involved in compensatory recovery of the cercal escape system in the cricket and can be compared and contrasted with the distinct pathways that have been identified upon deafferentation of the auditory system in this same animal.

Eagle syndrome: a rare pathology presented in a 3-Dimensional reconstructed view.

A 42-year-old male presented with 3-month history of constant right-sided frontal headaches, severe right-sided intermittent sharp jaw pain, odynophagia, globus pharyngis, and worsening episodes of blurry vision in his right eye. Cervicocerebral angiography demonstrated a prominent, 4 cm right sided styloid process with close proximity to the right internal carotid artery (ICA). The patient was referred to otorhinolaryngology for styloidectomy and continued care.

Resolution of hypoglossal nerve palsy after coil embolization of an anterior condylar confluence fistula.

A 69-year-old female presented with 2-year history of slurred speech, left-sided pulsatile tinnitus, and left-sided hypoglossal nerve palsy. Cerebral angiography demonstrated a left anterior condylar confluence fistula. She was treated with a transvenous coil embolization of the left condylar fistula pocket.

Financial barriers and inequity in medical education in India: challenges to training a diverse and representative healthcare workforce.

India has been historically challenged by an insufficient and heterogeneously clustered distribution of healthcare infrastructure. While resource-limited healthcare settings, such as major parts of India, require multidisciplinary approaches for improvement, one key approach is the recruitment and training of a healthcare workforce representative of its population. This requires overcoming barriers to equity and representation in Indian medical education that are multi-faceted, historical, and rooted in inequality. However, literature is lacking regarding the financial or economic barriers, and their implications on equity and representation in the Indian allopathic physician workforce, which this review sought to describe. Keyword-based searches were carried out in PubMed, Google Scholar, and Scopus in order to identify relevant literature published till November 2023. This state-of-the-art narrative review describes the existing multi-pronged economic barriers, recent and forthcoming changes deepening these barriers, and how these may limit opportunities for having a diverse workforce. Three sets of major economic barriers exist to becoming a specialized medical practitioner in India - resources required to get selected into an Indian medical school, resources required to pursue medical school, and resources required to get a residency position. The resources in this endeavor have historically included substantial efforts, finances, and privilege, but rising barriers in the medical education system have worsened the state of inequity. Preparation costs for medical school and residency entrance tests have risen steadily, which may be further exacerbated by recent major policy changes regarding licensing and residency selection. Additionally, considerable increases in direct and indirect costs of medical education have recently occurred. Urgent action in these areas may help the Indian population get access to a diverse and representative healthcare workforce and also help alleviate the shortage of primary care physicians in the country. Discussed are the reasons for rural healthcare disparities in India and potential solutions related to medical education.

The US Residency Selection Process After the United States Medical Licensing Examination Step 1 Pass/Fail Change: Overview for Applicants and Educators.

The United States Medical Licensing Examination (USMLE) Step 1, arguably the most significant assessment in the USMLE examination series, changed from a 3-digit score to a pass/fail outcome in January 2022. Given the rapidly evolving body of literature on this subject, this paper aims to provide a comprehensive review of the historical context and impact of this change on various stakeholders involved in residency selection. For this, relevant keyword-based searches were performed in PubMed, Google Scholar, and Scopus to identify relevant literature. Given the unique history of USMLE Step 1 in the US residency selection process and the score's correlation with future performance in board-certifying examinations in different specialties, this scoring change is predicted to significantly impact US Doctor of Medicine students, US Doctor of Osteopathic Medicine students, international medical graduates, and residency program directors, among others. The significance and the rationale of the pass/fail change along with the implications for both residency applicants and educators are also summarized in this paper. Although medical programs, academic institutions, and residency organizing bodies across the United States have swiftly stepped up to ensure a seamless transition and have attempted to ensure equity for all, the conversion process carries considerable uncertainty for residency applicants. For educators, the increasing number of applications conflicts with holistic application screening, leading to the expected greater use of objective measures, with USMLE Step 2 Clinical Knowledge likely becoming the preferred screening tool in lieu of Step 1.

Varying Degree of Overlap Following the Critical Steps of Lumbar Fusion and Short-term Outcomes.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: The present study analyzes the impact of end-overlap on short-term outcomes after single-level, posterior lumbar fusions. SUMMARY OF BACKGROUND DATA: Few studies have evaluated how "end-overlap" (i.e., surgical overlap after the critical elements of spinal procedures, such as during wound closure) influences surgical outcomes. METHODS: Retrospective analysis was performed on 3563 consecutive adult patients undergoing single-level, posterior-only lumbar fusion over a 6-year period at a multi-hospital university health system. Exclusion criteria included revision surgery, missing key health information, significantly elevated body mass index (>70), non-elective operations, non-general anesthesia, and unclean wounds. Outcomes included 30-day emergency department visit, readmission, reoperation, morbidity, and mortality. Univariate analysis was carried out on the sample population, then limited to patients with end-overlap. Subsequently, patients with the least end-overlap were exact-matched to patients with the most. Matching was performed based on key demographic variables-including sex and comorbid status-and attending surgeon, and then outcomes were compared between exact-matched cohorts. RESULTS: Among the entire sample population, no significant associations were found between the degree of end-overlap and short-term adverse events. Limited to cases with any end-overlap, increasing overlap was associated with increased 30-day emergency department visits ( P =0.049) but no other adverse outcomes. After controlling for confounding variables in the demographic-matched and demographic/surgeon-matched analyses, no differences in outcomes were observed between exact-matched cohorts. CONCLUSIONS: The degree of overlap after the critical steps of single-level lumbar fusion did not predict adverse short-term outcomes. This suggests that end-overlap is a safe practice within this surgical population.

Interhemispheric gravity-assisted approach for microsurgical resection of a splenium arteriovenous malformation.

The parietal interhemispheric approach employing gravity retraction with skeletonization of bridging veins provides an excellent operative window for safe, curative resection of splenial arteriovenous malformations.

Increasing Nonconcurrent Overlapping Surgery Is Not Associated With Outcome Changes in Lumbar Fusion.

BACKGROUND: There remains a paucity of literature on the impact of overlap on neurosurgical patient outcomes. The purpose of the present study was to correlate increasing duration of surgical overlap with short-term patient outcomes following lumbar fusion. METHODS: The present study retrospectively analyzed 1302 adult patients undergoing overlapping, single-level, posterior-only lumbar fusion within a single, multicenter, academic health system. Recorded outcomes included 30-day emergency department visits, readmission, reoperation, mortality, overall morbidity, and overall morbidity/surgical complications. The amount of overlap was calculated as a percentage of total overlap time. Comparison was made between patients with the most (top 10%) and least (bottom 40%) amount of overlap. Patients were then exact matched on key demographic factors but not by the attending surgeons. Subsequently, patients were exact matched by both demographic data and the attending surgeons. Univariate analysis was first carried out prior to matching and then on both the demographic-matched and surgeon-matched cohorts. Significance for all analyses was set at a P value of <0.05. RESULTS: Within the whole population, increasing duration of overlap was not correlated with any short-term outcome (P = 0.41-0.91). After exact matching, patients with the most and least durations of overlap did not have significant differences with respect to any short-term outcomes (P = 0.34-1.00). CONCLUSION: Increased amount of overlap is not associated with adverse short-term outcomes for single-level, posterior-only lumbar fusions. CLINICAL RELEVANCE: The present results suggest that increasing the duration of overlap during lumbar fusion surgery does not lead to inferior outcomes.

Postoperative outcomes and the association with overlap before or after the critical step of lumbar fusion.

OBJECTIVE: This study assesses how degree of overlap, either before or after the critical operative portion, affects lumbar fusion outcomes. METHODS: The authors retrospectively studied 3799 consecutive patients undergoing single-level, posterior-only lumbar fusion over 6 years (2013-2019) at a university health system. Outcomes recorded within 30-90 and 0-90 postoperative days included emergency department (ED) visit, readmission, reoperation, overall morbidity, and mortality. Furthermore, morbidity and mortality were recorded for the duration of follow-up. The amount of overlap that occurred before or after the critical portion of surgery was calculated as a percentage of total beginning or end operative time. Subsequent to initial whole-population analysis, coarsened exact-matched cohorts of patients were created with the least and most amounts of either beginning or end overlap. Univariate analysis was performed on both beginning and end overlap exact-matched cohorts, with significance set at p < 0.05. RESULTS: Equivalent outcomes were observed when comparing exact-matched patients. Among the whole population, the degree of beginning overlap was correlated with reduced ED visits within 30-90 and 0-90 days (p = 0.007, p = 0.009; respectively), and less 0-90 day morbidity (p = 0.037). Degree of end overlap was correlated with fewer 30-90 day ED visits (p = 0.015). When comparing only patients with overlap, degree of beginning overlap was correlated with fewer 0-90 day reoperations (p = 0.022), and no outcomes were correlated with degree of end overlap. CONCLUSIONS: The degree of overlap before or after the critical step of surgery does not lead to worse outcomes after lumbar fusion.

Trends in Matriculation from Neurological Surgery Training Programs into Academic Versus Private Practice.

OBJECTIVE: A career in academic neurosurgery is an arduous endeavor. Specific factors influencing physician practice preferences remain unclear. This study analyzes data from the American Association of Neurological Surgeons membership identifying the impact of several demographic and educational characteristics influencing neurosurgical career choices centered on academia, private practice, or a combination in the United States. METHODS: A list of all current neurosurgeons was obtained from the American Association of Neurological Surgeons membership, and information on physician characteristics was collected via internet searches and institutional databases. The practice type of all neurosurgeons considered in this study were categorized as follows: private practice, academic, or a combination of private practice and academic, termed privademic. These data were subsequently correlated to race, gender, current age, training at a top 40 National Institutes of Health-funded medical school or residency program, and current practice. RESULTS: The median age of private practice and academic neurosurgeons was 58.18 and 53.61 years, respectively (P < 0.001). Age was significantly associated with practicing in an academic setting (odds ratio 0.96), with younger neurosurgeons pursuing careers in academia. Data indicated a positive and statistically significant contribution of female gender (P < 0.001) and training at a top-40 National Institutes of Health-funded institution to practicing in an academic setting (P < 0.01). CONCLUSIONS: Neurosurgery as a field has grown significantly over the past century. The authors recommend that future efforts seek to diversify the neurosurgical workforce by considering practice setting, demographic characteristics, and educational background.

Microsurgical Clip Reconstruction of a Ruptured Internal Carotid Artery Terminus Blister Aneurysm Using a Reverse Picket Fence Technique.

BACKGROUND: Blister aneurysms are rare, technically challenging lesions that are typically ill defined and arise at nonbranch points of arteries. OBJECTIVE: To describe the microsurgical treatment of a ruptured blister aneurysm at the internal carotid artery (ICA) terminus using the reverse picket fence clipping technique. METHODS: The patient was a 60-yr-old male. He presented with a Hunt and Hess Grade 2, Fisher Grade 3 subarachnoid hemorrhage located in the bilateral sylvian fissures (right > left) and suprasellar cisterns. Computed tomography angiography demonstrated 2 aneurysms: a 2-mm right middle cerebral artery (MCA) aneurysm and a 2.5-mm right internal carotid artery (ICA) terminus blister aneurysm. Transradial cerebral angiography was undertaken which showed these similar sized aneurysms. Microsurgical treatment was chosen, and the patient underwent a right pterional craniotomy for clipping of his aneurysms. The patient consented to the procedure. RESULTS: The combination of stacked fenestrated clips repaired the vessel, with intraoperative fluorescein and indocyanine green angiography demonstrated normal filling of the MCA and ICA circulation with no delay. Intraoperative angiography confirmed induced moderate stenosis of the ICA terminus at about 50%, which is essential to close the blister aneurysm site by utilizing a portion of the normal vessel wall. CONCLUSION: Ruptured blister aneurysms at the ICA terminus can be safely repaired using the reverse picket fence technique for clipping.

Combined Endovascular and Microsurgical Management of a Tentorial Arteriovenous Malformation in a Hybrid Neurovascular Operating Room: 2-Dimensional Operative Video.

Tentorial margin arteriovenous malformations (AVMs) at the cerebello-mesencephalic fissure are deep lesions, which can be safely resected via a lateral supracerebellar infratentorial approach. This video illustrates the case of a patient who presented with hemorrhage from a tentorial AVM. He was managed in the hybrid neurovascular operating room with Onyx (Medtronic) embolization of a superior cerebellar artery feeder followed by resection of the AVM, which included cerebellar relaxation from lumbar cerebrospinal fluid (CSF) drainage and lateral positioning. Wide cisternal arachnoid dissection at the quadrigeminal cistern allowed for a straight trajectory to the AVM without fixed retraction. Intraoperative transradial angiography confirmed complete AVM exclusion. This video was deemed Institutional Review Board (IRB) exempt by the University of Pennsylvania IRB as it is considered a case report, which does not require IRB approval or patient consent. The patient consented to the procedure.

Overlap Before the Critical Step of Lumbar Fusion Does Not Lead to Increased Short-Term Morbidity.

BACKGROUND: Few studies have assessed the impact of overlapping surgery during different timepoints of neurosurgical procedures. OBJECTIVE: To evaluate the impact of overlap before the critical portion of surgery on short-term patient outcomes following lumbar fusion. METHODS: In total, 3799 consecutive patients who underwent single-level, posterior-only lumbar fusion over 6 yr (2013-2019) at an academic hospital system were retrospectively studied. Outcomes included 30-d emergency department (ED) visit, readmission, reoperation, mortality, overall morbidity, and overall morbidity/surgical complications. Duration of overlap that occurred before the critical portion of surgery was calculated as a percentage of total beginning operative time. Univariate logistic regression was used to assess the impact of incremental 1% increases in the duration of overlap within the whole population and patients with beginning overlap. Subsequently, univariate analysis was used to compare exact matched patients with the least (bottom 40%) and most amounts of overlap (100% beginning overlap). Coarsened exact matching was used to match patients on key demographic factors, as well as attending surgeon. Significance was set at a P-value < .05. RESULTS: Increased duration of beginning overlap was associated with a decrease in 30-d ED visit (P = .03) within all patients with beginning overlap, but not within the whole population undergoing lumbar fusion. Duration of beginning overlap was not associated with any other short-term morbidity or mortality outcome in either the whole population or patients with beginning overlap. CONCLUSION: Increased duration of overlap before the critical step of surgery does not predict adverse short-term outcomes after single-level, posterior-only lumbar fusion.

Duration of overlap during lumbar fusion does not predict outcomes.

INTRODUCTION: The relationship between degree of surgical overlap and adverse postoperative outcomes remains poorly defined. This study aims to evaluate the impact of increasing duration of overlap on lumbar fusion outcomes. PATIENTS AND METHODS: 1302 adult patients undergoing overlapping surgery during single-level, posterior-only lumbar fusion at a multi-hospital, university health system were retrospectively assessed. Amount of overlap was calculated as a percentage of total overlap time. Patients were separated into groups with the most (top 10% of patients) and least amounts of overlap (bottom 40% of patients). Using Coarsened Exact Matching, patients with the most and least amounts of overlap were matched on demographics alone, then on both demographics and attending surgeon. Univariate analysis was performed for the whole population and both matched cohorts to compare amount of overlap to risk of adverse postsurgical events. Significance for all analyses was p-value < 0.05. RESULTS: Duration of overlap was not associated with outcomes in the whole population, demographic-matched, or surgeon-matched analyses. Before exact matching, patients with the most amount of overlap had a significantly higher CCI score (p = 0.031) and shorter length of surgery (p = 0.006). In the demographic matched cohort, patients with increased overlap had a significantly shorter length of surgery (p = 0.001) only. In the surgeon matched cohort, there were no differences in length of surgery or CCI score. CONCLUSIONS: Duration of surgical overlap does not predict adverse outcomes following lumbar fusion. These results suggest that overlapping surgery is a safe practice within this common neurosurgical indication.

Overlapping single-level lumbar fusion and adverse short-term outcomes.

OBJECTIVE: There is a paucity of research on the safety of overlapping surgery. The purpose of this study was to evaluate the impact of overlapping surgery on a homogenous population of exactly matched patients undergoing single-level, posterior-only lumbar fusion. METHODS: The authors retrospectively analyzed case data of 3799 consecutive adult patients who underwent single-level, posterior-only lumbar fusion during a 6-year period (June 7, 2013, to April 29, 2019) at a multihospital university health system. Outcomes included 30-day emergency department (ED) visit, readmission, reoperation, and morbidity and mortality following surgery. Thereafter, coarsened exact matching was used to match patients with and without overlap on key demographic factors, including American Society of Anesthesiologists (ASA) class, Charlson Comorbidity Index (CCI) score, sex, and body mass index (BMI), among others. Patients were subsequently matched by both demographic data and by the specific surgeon performing the operation. Univariate analysis was carried out on the whole population, the demographically matched cohort, and the surgeon-matched cohort, with significance set at a p value < 0.05. RESULTS: There was no significant difference in morbidity or any short-term outcome, including readmission, reoperation, ED evaluation, and mortality. Among the demographically matched cohort and surgeon-matched cohort, there was no significant difference in age, sex, history of prior surgery, ASA class, or CCI score. Overlapping surgery patients in both the demographically matched cohort and the matched cohort limited by surgeon had longer durations of surgery (p < 0.01), but no increased morbidity or mortality was noted. Patients selected for overlap had fewer prior surgeries and lower ASA class and CCI score (p < 0.01). Patients with overlap also had a longer duration of surgery (p < 0.01) but not duration of closure. CONCLUSIONS: Exactly matched patients undergoing overlapping single-level lumbar fusion procedures had no increased short-term morbidity or mortality; however, duration of surgery was 20 minutes longer on average for overlapping operations. Further studies should assess long-term patient outcomes and the impact of overlap in this and other surgical procedures.

Outcomes Following Discectomy for Far Lateral Disc Herniation Are Not Predicted by Obstructive Sleep Apnea.

Introduction Previous studies have demonstrated that obstructive sleep apnea (OSA) is associated with adverse postoperative outcomes, but few studies have examined OSA in a purely spine surgery population. This study investigates the association of the STOP-Bang questionnaire, a screening tool for undiagnosed OSA, with adverse events following discectomy for far lateral disc herniation (FLDH). Methods All adult patients (n = 144) who underwent FLDH surgery at a single, multihospital, academic medical center (2013-2020) were retrospectively enrolled. Univariate logistic regression was performed to evaluate the relationship between risk of OSA (low- or high-risk) according to STOP-Bang score and postsurgical outcomes, including unplanned hospital readmissions, ED visits, and reoperations. Results Ninety-two patients underwent open FLDH surgery, while 52 underwent endoscopic procedures. High risk of OSA according to STOP-Bang score did not predict risk of readmission, ED visit, outpatient office visit, or reoperation of any kind within either 30 days or 30-90 days of surgery. High risk of OSA also did not predict risk of reoperation of any kind or repeat neurosurgical intervention within 30 days or 90 days of the index admission (either during the same admission or after discharge). Conclusion The STOP-Bang questionnaire is not a reliable tool for predicting post-operative morbidity and mortality for FLDH patients undergoing discectomy. Additional studies are needed to assess the impact of OSA on morbidity and mortality in other spine surgery populations.

Assessment of Gender Disparities in Short-Term and Long-Term Outcomes Following Posterior Fossa Tumor Resection.

Introduction The analysis of social determinants of health (SDOH) across different surgical populations is critical for the identification of health disparities and the development risk mitigation strategies among vulnerable patients. Research into the impact of gender on neurosurgical outcomes remains limited. The aim of the present study was to assess the effect of gender on outcomes, in a matched sample, following posterior fossa tumor resection, a high-risk neurosurgical procedure. Methods Two hundred seventy-eight consecutive patients undergoing posterior fossa tumor resection over a six-year period (June 07, 2013, to April 29, 2019) at a single academic medical system were retrospectively evaluated. Short-term outcomes included 30- and 90-day rates of emergency department (ED) visit, readmission, reoperation, and mortality. Long-term outcomes included mortality and reoperation for the duration of follow-up. Firstly, male and female patients in the entire pre-match sample were compared. Thereafter, coarsened exact matching was employed to control for confounding variables, matching male and female patients on key demographic factors - including history of prior surgery, median household income, and race, amongst others - and outcome comparison was repeated. Results In both the entire pre-match sample and matched cohort analyses, no significant differences in adverse postsurgical events were discerned between the female and male patients when evaluating 30-day or 90-day rates of ED visit, readmission, reoperation, and mortality. There were also no differences in reoperation or mortality for the duration of follow-up. Conclusion Gender does not appear to impact short- or long-term outcomes following posterior fossa tumor resection. As such, risk assessment and mitigation strategies in this population should focus on other SDOH. Further studies should assess the role of other SDOH within this population.