bluuebunny/crossref_metadata_2025_split huggingface dataset:
310 "The "Bright Falx" Sign - Midline Embolic Penetration is Associated With Faster Resolution of CSDH Following MMA Embolization
Authors: Samarage Hasitha Milan , Kim Wi Jin , Colby Geoffrey P. 
Published: March 2023

INTRODUCTION:
CSDHs are common in the elderly and patients taking antiplatelet/anticoagulation medications. MMA embolization has become an adjunctive treatment to observation and surgery. Despite many embolization techniques, best practices for optimal CSDH resolution remain unknown.

METHODS:
Retrospective chart review was done on all patients who underwent MMA embolization for CSDHs between January 2017 and June 2021. Patient demographics, clinical presentation, anticoagulant use, and radiographic features were collected. Pre- and post-embolization CT scans were analyzed for volumetric changes and assessed for midline penetration of embolic material in the falx.

RESULTS:
MMA embolization was performed in 37 patients and 53 hemispheres. Older patients took longer to obtain complete resolution of CSDHs (r = 0.47, p = 0.03). Patients with larger pre-embolization (r = 0.57, p = 0.007) and post-embolization (r = 0.56, p = 0.008) CSDH volumes took longer to completely resolve. Patients who had nBCA embolization with midline penetration, as evidenced by the "bright falx" sign, had faster improvement rates than those who did not (5.64 cm3/d vs. 1.2 cm3/d, p = 0.02).

CONCLUSIONS:
Distal penetration of embolic material, particularly nBCA, into the falx may lead to more rapid improvement of CSDH.
313 Passive Flow-Reversal With Balloon-Guide Catheter for Transfemoral Carotid Artery Stenting: Proof of Concept, Technical Description and Experience
Authors: Monteiro Andre , Cappuzzo Justin Mark , Waqas Muhammad , Lim Jaims , Baig Ammad , Khawar Wasiq , Popoola Daniel , Davies Jason , Siddiqui Adnan Hussain , Levy Elad I. , Snyder Kenneth Vincent 
Published: March 2023

INTRODUCTION:
The use of modern transfemoral balloon guide catheters (BGC) for flow reversal during carotid artery stenting (CAS) is scarcely described in literature but represents a promising and efficient technique for embolic protection.

METHODS:
We performed a retrospective analysis of patients ≥ 18-year-old who underwent elective CAS with the use of flow-reversal through the Walrus BGC. The BGC is positioned in the common carotid artery and inflated, followed by opening of the stop-cock for passive reversal of flow. We utilized a robotic transcranial Doppler monitoring during this technique for proof of concept. Patients’ characteristics, procedural details and clinical follow-up were evaluated.

RESULTS:
One-hundred and ten patients were included. Mean age was 69.1 years ± SD 9.6 and 30 (27.3%) were female. Most common comorbidities were hyperlipidemia (81.8%) and hypertension (73.6%). 54 (49.1%) patients were symptomatic. 102 (92.7%) patients had stenosis ≥70%. Contralateral stenosis ≥50% was present in 54 (49.1%) patients. Distal filters were used in 91 (82.7%) cases. Angioplasty was performed in 86 (78.2%) patients. Stenting was successful in 100% of cases. There were no periprocedural TIA or stroke. Stroke or TIA and mortality were both observed in only two (1.8%) patients during 30-days follow-up, of which one was due to non-compliance with antiplatelet regimen.

CONCLUSIONS:
In our institution’s experience, this technique was safe, feasible and efficient, with 100% technical success and no periprocedural thromboembolic complications. More extensive studies are needed to establish the role of proximal protection with flow-reversal using modern BGCs.
315 Use of Flow Diverter in the Treatment of Anterior Communicating Artery Aneurysms: A Multicenter Experience (FEAR ME study)
Authors: Benalia Victor , Cortez Gustavo , Mounayer Charbel , Saatci Isil , Cekirge Saruhan , Koçer Nací , Islak Civan , Dabus Guilherme , Brinjikji Waleed , Baltacıoğlu Feyyaz , Pereira Vitor Mendes , Nishi Hidehisa , Siddiqui Adnan , Lopes Demetrius K. , Aghaebrahim Amin , Sauvageau Eric , Hanel Ricardo A. 
Published: March 2023

INTRODUCTION:
The anterior communicating artery (AcomA) is among the most common s ites of intracranial aneurysms and has an increased risk of rupture compared to other locations. The safety and efficacy of flow diverters utilization for aneurysm treatment have been demonstrated for many locations, less consistently for AcomA Complex. We present the most extensive analysis in the neurosurgical literature for flow diverter treatment in AcomA aneurysms.

METHODS:
Databases from nine centers were retrospectively reviewed for AcomA aneurysms treated with flow diverters. Demographic information, clinical presentation, radiographic characteristics, procedural complications, and post-procedure outcomes were obtained.

RESULTS:
A total of 181 patients harboring 186 AcomA aneurysms were treated between January 2012 to December 2021. Ninety-one were female (54.1%), median age was 61[51 – 68]. Most aneurysms were unruptured and located at the AcomA itself. Half of the cohort had similar anterior cerebral artery sizes (51.8%). The most common morphology was saccular (91.9%), with a branch involvement in 30.4% of cases. Median vessel diameter was 2.35 mm, and Pipeline Flex was the most prevalent device (39.8%). Median follow-up time was 16 months, with a complete occlusion rate of 85.6% in the last follow-up. Functional independence (mRS 0-2) was reported in 96.7% of patients at the last follow-up. Major complication rate was 2.2%, and mortality rate was 2.2% (4/181).

CONCLUSIONS:
Our results suggest that flow diverter is a useful tool as treatment modality for AcomA aneurysms. Mid-term results indicated favorable aneurysm occlusion rates and a lower complication rate. Additional prospective studies with longer follow-up and independent adjudication are warranted to assess these results better.
316 Neurosurgical Federated Learning: A Multi-Center Collaboration to Detect Intracranial Hemorrhage Without Directly Sharing Data
Authors: Cheung Alexander , Moin Mustafa Nasir , Kwon Fred , Guan Jiahui , Liu Chris , Jiang Lavender , Raimondo Christian , Chotai Silky , Chambless Lola Blackwell , Ahmad Hasan S. , Chauhan Daksh , Yoon Jang Won , Hollon Todd Charles , Buch Vivek , Kondziolka Douglas , Chen Dinah , Al-Aswad Lama , Aphinyanaphongs Yindalon , Oermann Eric 
Published: March 2023

INTRODUCTION:
The development of accurate and generalizable machine learning algorithms requires sufficient quantities of diverse data. This poses a challenge in healthcare due to the sensitive and siloed nature of biomedical information. Decentralized algorithms through a federated learning (FL) paradigm avoid the need for data aggregation by instead distributing algorithms to the data itself before centrally updating one global model.

METHODS:
Five academic neurosurgery departments across the US collaborated to establish a federated network using computed tomography (CT) scans for prototyping. We trained a convolutional neural network to detect the presence of ICH through FL and benchmarked this against a standard, centralized training approach. Models were validated on each site’s data and tested on a held-out dataset to determine the area under the ROC curve (AUROC).

RESULTS:
A federated network of practicing neurosurgeon-scientists was successfully initiated and used to train a model for predicting ICH across the US. The federated model achieved an average AUROC of 0.9487 at predicting all types of ICH compared to a benchmark non-FL model AUROC of 0.9753, although performance varied by hemorrhage subtype. Subdural bleeds had the lowest AUROC (0.9257) while intraventricular bleeds had the highest (0.9751) on hold-out data. The global FL model consistently achieved top-three performance (of five) when validated on data from each site, suggesting improved generalizability. A qualitative survey of participants revealed that a majority found the process of connecting to the federated network easy.

CONCLUSIONS:
This study demonstrates the feasibility of implementing a federated network for multi-institutional collaboration amongst clinicians and using FL to conduct machine learning research without the transfer of data between sites, thereby opening up a new paradigm for neurosurgical collaboration.
317 Pilot Analysis of Surgeon Instrument Utilization Signatures Based on Shannon Entropy for Surgeon Performance Assessment in a Cadaveric Carotid Artery Injury Control Simulation
Authors: Balu Alan , Pangal Dhiraj J. , Kugener Guillaume , Donoho Daniel 
Published: March 2023

INTRODUCTION:
Automated video-based feedback for a surgeon’s technical skills would improve patient care and facilitate trainee education, but current feedback methods require the development of task-specific metrics. A generalizable, automated method of surgeon skills assessment with surgeon tool-usage signatures could expedite the development and validation of video-based feedback methods.

METHODS:
Annotated images from the publicly-available SOCAL dataset were used to train an off-the-shelf computer vision model (YOLOv4) which detected surgical instruments. Shannon entropy of unique instruments combinations was calculated from each surgical trial. Logistic regression was used to predict trial success using Shannon entropy.

RESULTS:
Surgeon signatures based on Shannon entropy were created for each trial and each surgeon. Instrument usage patterns demonstrated differences between successful and unsuccessful trials. Shannon entropy of instrument combinations demonstrated significant correlation with trial success (p < 0.001) and predicted success with 97% average precision and 78% accuracy using computer vision detections. Unsuccessful trials displayed a rapid initial peak in entropy which then declined over time. In contrast, successful trials demonstrated slower progression of tool usage with gradually increasing use of a critical, final maneuver.

CONCLUSIONS:
Surgeon signatures based on Shannon entropy predicted task success with acceptable accuracy and revealed patterns between successful and unsuccessful trials. Shannon entropy offers a generalizable and summative signal about surgeon performance, regardless of the task, and can predict outcomes based only on the probabilities of unique instrument combinations. Future efforts will describe the instrument movement signatures.
324 SpineTrak: The First Randomized Control Trial Using the Apple Watch to Objectively Track Spine Surgical Patients
Authors: Leung Christopher , Fatemi Parastou , Yerneni Ketan , Desai Atman , Tompkins-Lane Christy , Zygourakis Corinna Clio 
Published: March 2023

INTRODUCTION:
Mobilization after surgery reduces complications and is associated with improved survival and psychological well-being, and decreased length of hospitalization. Current methods for evaluating the outcomes of spine surgery patients rely on patient-reported outcome measures (PROMs). There are numerous wearable activity monitors, including the Apple Watch (AW), that can track and monitor mobility.

METHODS:
Eligibility: Adult patients undergoing elective spine surgery. Patients randomized 1:1 to intervention vs control group. Intervention patients receive AW, download study-specific application to collect health measures from AW. Visual reports are provided to intervention patients and surgeons. All patients complete PROMs pre-operatively and at 6-weeks, 3-months, 6 months, 1-year post-operatively. All patients complete study-specific questionnaire regarding satisfaction and understanding of recovery. Target enrollment is 100 intervention and 100 control patients.

RESULTS:
To date, we have enrolled 163 patients (n = 83 intervention; n = 80 control). Intervention participants (n = 50) have worn AW 91% of the days and for 14.1 hours/day. At 6-week post-operative visits, 67% of patients responded that they were very satisfied with the use of the AW in their spine care and that seeing their AW activity tracking data was helpful. 94% of neurosurgeons agreed that the AW summary helped them understand how their patient was doing post-operatively.

CONCLUSIONS:
Preliminary results of participants indicate patients are compliant with wearing the AW, and both patients and surgeons are satisfied with its use in their spine care. Initial analyses do not show a correlation between PROMs and objective measures, emphasizing the need for a metric that combines objective and subjective measures to track patient's recovery in real-time.
335 Development and Validation of a Predictive Score for Persistent Instability Following Conservative Treatment in Type II Odontoid Fractures
Authors: Page Paul , Ammanuel Simon G. , Brooks Nathaniel P. , Resnick Daniel K. 
Published: March 2023

INTRODUCTION:
Odontoid fractures are common cervical spine fractures, however significant controversy exists regarding their treatment. While risk factors for failure of conservative therapy have been identified, no predictive risk score has been developed to aid in decision making regarding surgical intervention or conservative therapy.

METHODS:
A retrospective review was conducted of all patients evaluated at a level one trauma center from 2005 to 2021. Patients identified with Type II Odontoid Fractures as classified by the Anderson D’Alonzo Classification system who were treated with external orthosis were included in analysis. Patients were considered to have failed conservative therapy if they were offered surgical intervention due to nonunion and continued motion on flexion extension x-rays. A machine learning method (RiskSLIM) was then utilized to created a risk stratification score to identify patients at high risk for requiring surgical intervention due to persistent instability.

RESULTS:
In total, 138 patients were identified as presenting with type II odontoid fractures that were treated conservatively. Of these, 38 patients demonstrated persistent instability following conservative therapy with cervical orthosis. The Odontoid Fracture Predictive Model (OFPM) was created using a machine learning algorithm with a five-fold cross validation area under the curve of 0.7389 (95% CI: 0.671 to 0.808) and calibration error of 18.6%. Predictive factors were found to include anterior or posterior displacement, displacement greater than 5 mm, comminution at the fracture base, and history of smoking. The probability of persistent instability was <5% with a score of 0 and 88% with a score of 5.

CONCLUSIONS:
The OFPM model is a quick and accurate tool to assist in clinical decision making in patients with type II odontoid fractures.
339 Mineral Coated Micropaarticles Delivering Chondroitinase ABC mRNA Improves Motor Function After Spinal Cord Injury in Rats
Authors: Hanna Amgad S. , Hellenbrand Daniel , Khalil Andrew , Murphy William 
Published: March 2023

INTRODUCTION:
Currently, there are no treatments to help regain a significant amount of the function that is lost after spinal cord injury (SCI). A primary reason for the lack in functional recovery is the glial scar, which forms after SCI and inhibits axonal regeneration. Chondroitinase ABC (ChABC), a bacterial enzyme, digests one of the main axonal inhibitors in the glial scar, chondroitin sulfate proteoglycans (CSPGs), and results in axonal regeneration and functional recovery. However, ChABC is not thermally stable and quickly becomes inactive at body temperature. Recently, messenger RNA (mRNA) delivery has emerged as an attractive strategy for non-virally producing proteins in vivo with higher activity than recombinant proteins and a more desirable safety profile than viral gene delivery.

METHODS:
ChABC mRNA synthesis was designed in Benchling Molecular Biology Suite and ordered as-synthesized plasmid (Genscript). Mineral coatings were grown on hydroxyapatite microparticles and lipoplexes with mRNA were bound to the coatings. Rat spinal cords were contused at the T10 level and the glial scar was allowed to form. Seven days post-injury MCMs with ChABC mRNA were injected into the epicenter of the injury. Rat Hindlimb function was assessed for seven weeks before the rats were harvested. Lastly, immunohistochemistry was used to assess CSPG digestion and axonal sprouting.

RESULTS:
MCMs delivering ChABC mRNA forced local overexpression of ChABC and significantly digested CSPGs after SCI, resulting in axonal sprouting and a significant improvement in hindlimb function.

CONCLUSIONS:
MCMs efficiently delivered ChABC mRNA to digest CSPGs in the glial scar after SCI.
342 Predicting Early Disease Progression in Tectal Plate Gliomas
Authors: Bauman Megan , Giesken Max , Naylor Ryan M. , Daniels David J. 
Published: March 2023

INTRODUCTION:
Tectal gliomas are slow-growing tumors of the midbrain. Due to their indolent nature, treatment mainly consists of observation and management of hydrocephalus. However, a subset of tectal gliomas may exhibit tumor enlargement and disease progression. Currently, there are no established guidelines for predicting future progression of tectal gliomas. Further, given the rarity of these tumors, studies in the literature are limited to <50 patients.

METHODS:
We performed a retrospective chart review of 172 patients diagnosed with tectal glioma. In addition to descriptive statistics, we performed univariate analysis using Student’s t-test and Chi-squared testing to determine if significant differences exist between patients with tumor progression versus those without progression.

RESULTS:
The median patient age was 24 years (range: 0-73 years); of these, 69 were pediatric (≤18 years). Hydrocephalus was present in 64% of cases. Lesions were incidentally detected in 37% of the cohort and were only present in the adult population. Of the patients that had > 1 year follow-up (n = 145), 26 experienced radiological progression (18%) with 19 requiring tumor-directed treatment (13%). Predictors of progression included younger age at diagnosis (p = 0.005), expansion of the lesion beyond the tectum on initial imaging (p < 0.001), moderate T1 signal (p < 0.001), and mild or moderate contrast enhancement (p = 0.011 and p < 0.001, respectively). At most recent follow-up, 92% had stable disease, 3% had progressive disease, 1% died from tumor progression, and 3% died of other causes.

CONCLUSIONS:
Certain characteristics of radiographic imaging may be predictive of future disease progression. In patients with progression, excellent survival can be achieved if progression is detected early and appropriate treatment is initiated.
354 Decreasing Blood Transfusions with a Multidisciplinary Intra-Operative Algorithm in Open Craniosynostosis Surgery
Authors: Drapeau Annie Isabelle , Valenti Olivia , Khansa Ibrahim , Pearson Gregory , Alalade Emmanuel , Smith Ashley 
Published: March 2023

INTRODUCTION:
Blood transfusions are common in craniosynostosis surgery. Lack of an intra-operative transfusion protocol is a known risk factor for increased transfusion in these surgeries.

METHODS:
Quality improvement methodology was used (Institute for Healthcare Improvement model). A multidisciplinary team proceeded with a survey of anesthesiology teams to evaluate readiness for change; creation of an intra-operative algorithm (guiding decision making, timing of measuring hemoglobin, administration of fluid resuscitation, and indications for blood transfusion); and integration of the algorithm into the surgery time out. No modifications were made regarding the type of general anesthesia and surgical technique (1 neurosurgeon, 2 plastic surgeons). Data collected: use of the intra-operative algorithm, administration of blood products, lowest hemoglobin recorded during admission, and other relevant surgical details. Minimally invasive surgeries were excluded.

RESULTS:
Eighty-two surgeries were included in three cohorts: baseline (2018, n = 6), project initiation (2019-2020, n = 44), and post-intervention (2021-2022, n = 32). After implementation, the algorithm was used in all cases. Transfusions given in stable patients with a hemoglobin >7.5 g/dL decreased from a baseline of 40.0% to 0% (p < 0.01). This improvement was demonstrated with a centerline shift on a statistical process control chart (Aggregate Point Rule). Overall transfusion rate decreased from a baseline of 100% to 59.4% post-intervention (p = 0.07). Those receiving a transfusion did not require more than 1 unit of packed red blood cells. No transfusions were required beyond post-operative day 1.

CONCLUSIONS:
Implementation of a multidisciplinary intra-operative transfusion algorithm for open craniosynostosis surgery led to meaningful decrease in blood transfusions. This was achieved without changing surgical technique or introducing complex adjuncts.
378 RAGE Ablation Attenuates Glioma Progression and Enhances Tumor Immune Responses by Suppressing Galectin-3 Expression
Authors: Dayyani Mojtaba , Zhang Ian , Liu Shunan , Zhang Leying , Liang Rongrui , Fang Qinxiao , Zhao Jie , Ren Lyuzhi , Medina Eric , Filippov Aleksandr , Bonjoc Kimberley-Jane , Chaudhry Ammar , Bild Andrea , Badie Behnam 
Published: March 2023

INTRODUCTION:
Malignant gliomas consist of heterogenous cellular components that have adopted multiple overlapping escape mechanisms that overcome both targeted and immune-based therapies. The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily that is activated by diverse proinflammatory ligands present in the tumor microenvironment (TME). Activation of RAGE by its ligands stimulates multiple signaling pathways that are important in tumor growth, invasion, and immune escape.

METHODS:
We evaluated genetic ablation of RAGE on the tumorigenicity of two syngeneic murine glioma models. RAGE expression was inhibited in the GL261 and K-Luc gliomas by shRNA and CRSPR/Cas9 techniques prior to intracranial implantation. Tumor growth, invasion, and inflammatory responses were examined by immunohistochemistry, qPCR, ELISA, western blotting, NanoString, flow cytometry, and in vivo survival analysis.

RESULTS:
Intracellular RAGE ablation abrogated glioma growth and invasion by suppressing AKT and ERK1/2 activities and by downregulating MMP9 expression. Interestingly, RAGE inhibition also enhanced tumor inflammatory responses by downregulating the expression of galectin-3, rendered the immunotherapy resistant K-Luc gliomas responsive to immune checkpoint blockade therapy, and significantly increased survival.

CONCLUSIONS:
This study is the first to link RAGE expression with galactin-3 as an immune modulator in glioblastoma and revealed that the effect of glioma RAGE expression on TME was mediated through downregulation of Gal-3 and subsequent polarization of Tumor-associated macrophages. The therapeutic significance of RAGE downregulation was demonstrated by sensitizing a highly invasive and immune-resistant glioma model to immune checkpoint blockade and strongly supports the development of RAGE ablation as a complementary treatment strategy for malignant gliomas.