Charge distribution studies in the epi-cadmium neutron induced fission of 238Pu.

Studies on charge distribution have been carried out in the epi-cadmium neutron induced fission of 238Pu for the first time. Experimentally fractional cumulative yields (FCY) and independent yields (IY) of various fission products have been measured by using an off-line γ-ray spectrometric technique. From the FCY values, the charge distribution parameters such as the isobaric width parameter (σZ), most probable charge (ZP) and the charge polarization (ΔΖEXPT) as a function of fragment mass were obtained. On the other hand, from the measured IY values, isotopic width parameter (σA), the most probable mass (AP) and the elemental yields (YZ) of Sn, Sb, Te, I, Xe, Cs, Ba, La, Ce and Pr were determined by using a non-linear fit. From the YZ values, the proton even-odd effect (δp) was obtained for the first time. The isobaric and isotopic charge distribution parameters in the 238Pu(nf, f) reaction were compared with the similar data in the thermal neutron induced fission of 238Pu and other actinides to examine the role of excitation energy.

Independent isomeric yield ratios of fission products in the epi-cadmium neutron induced fission of 233U.

The independent isomeric yield ratios (IR) of 128,130,132Sb, 131,133Te, 132,134,136I, 135Xe and 138Cs have been measured in the epi-cadmium neutron induced fission of 233U by using an off-line gamma-ray spectrometric technique. The average neutron energy of the epi-cadmium reactor neutron spectrum is 1.9 MeV. The root mean square fragment angular momenta (JRMS) were deduced from the IR values by using spin dependent statistical model analysis. The IR and JRMS values of considered fission products in the epi-cadmium neutron induced fission of 233U were compared with the literature data in the thermal neutron induced fission of 233U to examine the influence of excitation energy on nuclear structure effect.

Association Between Race and Short-Term Outcomes Across 3988 Consecutive Single-Level Spinal Fusions.

BACKGROUND AND OBJECTIVES: Race has implications for access to medical care. However, the impact of race, after access to care has been attained, remains poorly understood. The objective of this study was to isolate the relationship between race and short-term outcomes across patients undergoing a single, common neurosurgical procedure. METHODS: In this retrospective cohort study, 3988 consecutive patients undergoing single-level, posterior-only open lumbar fusion at a single, multihospital, academic medical center were enrolled over a 6-year period. Among them, 3406 patients self-identified as White, and 582 patients self-identified as Black. Outcome disparities between all White patients vs all Black patients were estimated using logistic regression. Subsequently, coarsened exact matching controlled for outcome-mitigating factors; White and Black patients were exact-matched 1:1 on key demographic and health characteristics (matched n = 1018). Primary outcomes included 30-day and 90-day hospital readmissions, emergency department (ED) visits, reoperations, mortality, discharge disposition, and intraoperative complication. RESULTS: Before matching, Black patients experienced increased rate of nonhome discharge, readmissions, ED visits, and reoperations (all P < .001). After exact matching, Black patients were less likely to be discharged to home (odds ratio [OR] 2.68, P < .001) and had higher risk of 30-day and 90-day readmissions (OR 2.24, P < .001; OR 1.91, P < .001; respectively) and ED visits (OR 1.79, P = .017; OR 2.09, P < .001). Black patients did not experience greater risk of intraoperative complication (unintentional durotomy). CONCLUSION: Between otherwise homogenous spinal fusion cohorts, Black patients experienced unfavorable short-term outcomes. These disparities were not explained by differences in intraoperative complications. Further investigation must characterize and mitigate institutional and societal factors that contribute to outcome disparities.

Determining Differences in Perioperative Functional Mobility Patterns in Lumbar Decompression Versus Fusion Patients Using Smartphone Activity Data.

BACKGROUND AND OBJECTIVES: Smartphone activity data recorded through high-fidelity accelerometry can provide accurate postoperative assessments of patient mobility. The "big data" available through smartphones allows for advanced analyses, yielding insight into patient well-being. This study compared rate of change in functional activity data between lumbar fusion (LF) and lumbar decompression (LD) patients to determine preoperative and postoperative course differences. METHODS: Twenty-three LF and 18 LD patients were retrospectively included. Activity data (steps per day) recorded in Apple Health, encompassing over 70 000 perioperative data points, was classified into 6 temporal epochs representing distinct functional states, including acute preoperative decline, immediate postoperative recovery, and postoperative decline. The daily rate of change of each patient's step counts was calculated for each perioperative epoch. RESULTS: Patients undergoing LF demonstrated steeper preoperative declines than LD patients based on the first derivative of step count data (P = .045). In the surgical recovery phase, LF patients had slower recoveries (P = .041), and LF patients experienced steeper postoperative secondary declines than LD patients did (P = .010). The rate of change of steps per day demonstrated varying perioperative trajectories that were not explained by differences in age, comorbidities, or levels operated. CONCLUSION: Patients undergoing LF and LD have distinct perioperative activity profiles characterized by the rate of change in the patient daily steps. Daily steps and their rate of change is thus a valuable metric in phenotyping patients and understanding their postsurgical outcomes. Prospective studies are needed to expand upon these data and establish causal links between preoperative patient mobility, patient characteristics, and postoperative functional outcomes.

Effects of Augmented Reality on Thoracolumbar Pedicle Screw Instrumentation Across Different Levels of Surgical Experience.

OBJECTIVE: Augmented reality (AR) is an emerging technology that may accelerate skill acquisition and improve accuracy of thoracolumbar pedicle screw placements. We aimed to quantify the relative assistance of AR compared with freehand (FH) pedicle screw accuracy across different surgical experience levels. METHODS: A spine fellowship-trained and board-certified attending neurosurgeon, postgraduate year 4 neurosurgery resident, and second-year medical student placed 32 FH and 32 AR-assisted thoracolumbar pedicle screws in 3 cadavers. A cableless, voice-activated AR system was paired with a headset. Accuracy was assessed using χ2 analysis and the Gertzbein-Robbins scale. Angular error, distance error, and time per pedicle screw were collected and compared. RESULTS: The attending neurosurgeon had 91.6% (11/12) clinically acceptable (Gertzbein-Robbins scale A or B) insertion in both FH and AR groups; the resident neurosurgeon had 100% (9/9) FH and AR in both cases; the medical student had 72.3% (8/11) FH accuracy and 81.8% (9/11) AR accuracy. The medical student displayed significantly lower ideal (Gertzbein-Robbins scale A) FH accuracy compared with the resident neurosurgeon (P = 0.017) and attending neurosurgeon (P = 0.005), but no difference when using AR. FH screw placement was faster by both the attending neurosurgeon (median 46 seconds vs. 94.5 seconds, P = 0.0047) and the neurosurgery resident neurosurgeon (median 144 seconds vs. 140 seconds, P = 0.05). Total clinically acceptable AR and FH accuracy was 90.6% (29/32) and 87.5% (28/32), respectively (P = 0.69). CONCLUSIONS: AR screw placement allowed an inexperienced medical student to double their accuracy in 1 training session. With subsequent iterations, this promising technology could serve as an important tool for surgical training.

Large Language Model-Based Neurosurgical Evaluation Matrix: A Novel Scoring Criteria to Assess the Efficacy of ChatGPT as an Educational Tool for Neurosurgery Board Preparation.

INTRODUCTION: Technological advancements are reshaping medical education, with digital tools becoming essential in all levels of training. Amidst this transformation, the study explores the potential of ChatGPT, an artificial intelligence model by OpenAI, in enhancing neurosurgical board education. The focus extends beyond technology adoption to its effective utilization, with ChatGPT's proficiency evaluated against practice questions from the Primary Neurosurgery Written Board Exam. METHODS: Using the Congress of Neurologic Surgeons (CNS) Self-Assessment Neurosurgery (SANS) Exam Board Review Prep questions, we conducted 3 rounds of analysis with ChatGPT. We developed a novel ChatGPT Neurosurgical Evaluation Matrix (CNEM) to assess the output quality, accuracy, concordance, and clarity of ChatGPT's answers. RESULTS: ChatGPT achieved spot-on accuracy for 66.7% of prompted questions, 59.4% of unprompted questions, and 63.9% of unprompted questions with a leading phrase. Stratified by topic, accuracy ranged from 50.0% (Vascular) to 78.8% (Neuropathology). In comparison to SANS explanations, ChatGPT output was considered better in 19.1% of questions, equal in 51.6%, and worse in 29.3%. Concordance analysis showed that 95.5% of unprompted ChatGPT outputs and 97.4% of unprompted outputs with a leading phrase were aligned. CONCLUSIONS: Our study evaluated the performance of ChatGPT in neurosurgical board education by assessing its accuracy, clarity, and concordance. The findings highlight the potential and challenges of integrating AI technologies like ChatGPT into medical and neurosurgical board education. Further research is needed to refine these tools and optimize their performance for enhanced medical education and patient care.

Relationship Between Comorbidity Burden and Short-Term Outcomes Across 4680 Consecutive Spinal Fusions.

OBJECTIVE: Preoperative management requires the identification and optimization of modifiable medical comorbidities, though few studies isolate comorbid status from related patient-level variables. This study evaluates Charlson Comorbidity Index (CCI)-an easily derived measure of aggregate medical comorbidity-to predict outcomes from spinal fusion surgery. Coarsened exact matching is employed to control for key patient characteristics and isolate CCI. METHODS: We retrospectively assessed 4680 consecutive patients undergoing single-level, posterior-only lumbar fusion at a single academic center. Logistic regression evaluated the univariate relationship between CCI and patient outcomes. Coarsened exact matching generated exact demographic matches between patients with high comorbid status (CCI >6) or no medical comorbidities (matched n = 524). Patients were matched 1:1 on factors associated with surgical outcomes, and outcomes were compared between matched cohorts. Primary outcomes included surgical complications, discharge status, 30- and 90-day risk of readmission, emergency department (ED) visits, reoperation, and mortality. RESULTS: Univariate regression of increasing CCI was significantly associated with non-home discharge, as well as 30- and 90-day readmission, ED visits, and mortality (all P < 0.05). Subsequent isolation of comorbidity between otherwise exact-matched cohorts found comorbid status did not affect readmissions, reoperations, or mortality; high CCI score was significantly associated with non-home discharge (OR = 2.50, P < 0.001) and 30-day (OR = 2.44, P = 0.02) and 90-day (OR = 2.29, P = 0.008) ED evaluation. CONCLUSIONS: Comorbidity, measured by CCI, did not increase the risk of readmission, reoperation, or mortality. Single-level, posterior lumbar fusions may be safe in appropriately selected patients regardless of comorbid status. Future studies should determine whether CCI can guide discharge planning and postoperative optimization.

Multi-layer approach to complex traumatic anterior skull base fracture repair: A case report.

Background: Anterior skull base fractures represent a unique challenge for neurosurgical repair due to the potential for orbital injury and the proximity to the air sinuses, yielding increased possibility for infection, and persistent cerebrospinal fluid (CSF) leak. While multiple techniques are available for the repair of anterior skull base defects, there exists a paucity of robust, long-term clinical data to guide the optimal surgical management of these fractures. Case Description: We present the case of a complex, traumatic penetrating anterior skull base fracture, and describe a multi-layered approach for successful repair - namely, with the use of a temporally-based pericranial flap, split-thickness frontal bone graft, and autogenous abdominal fat graft. The patient was followed for nine months postoperatively, over which time she experienced no significant complications. Conclusion: The goal of successful anterior skull base repair involves creating a durable, watertight separation between intra and extracranial compartments to prevent CSF leak, protect intracranial structures, and minimize infection risk. The temporally-based pericranial flap, split-thickness frontal bone graft, and autogenous abdominal fat graft represent safe and efficacious approaches to achieve lasting repair.

Significance of Hypofractionated Radiotherapy in Postoperative Irradiation for Breast Cancer: An Asian Multi-institutional Prospective Study.

AIMS: There is a need for the adequate distribution of healthcare resources in Southeast Asia. Many countries in the region have more patients with advanced breast cancer who are eligible for postmastectomy radiotherapy (PMRT). Therefore, it is critical that hypofractionated PMRT is effective in most of these patients. This study investigated the significance of postoperative hypofractionated radiotherapy in patients with breast cancer, including advanced breast cancer, in these countries. MATERIALS AND METHODS: Eighteen facilities in 10 Asian countries participated in this prospective, interventional, single-arm study. The study included two independent regimens: hypofractionated whole-breast irradiation (WBI) for patients who had undergone breast-conserving surgery and hypofractionated PMRT for patients who had undergone total mastectomy at a dose of 43.2 Gy in 16 fractions. In the hypofractionated WBI group, patients with high-grade factors received additional 8.1 Gy boost irradiation sessions for the tumour bed in three fractions. RESULTS: Between February 2013 and October 2019, 227 and 222 patients were enrolled in the hypofractionated WBI and hypofractionated PMRT groups, respectively. The median follow-up periods in the hypofractionated WBI and hypofractionated PMRT groups were 61 and 60 months, respectively. The 5-year locoregional control rates were 98.9% (95% confidence interval 97.4-100.0) and 96.3% (95% confidence interval 93.2-99.4) in the hypofractionated WBI and hypofractionated PMRT groups, respectively. Regarding adverse events, grade 3 acute dermatitis was observed in 2.2% and 4.9% of patients in the hypofractionated WBI and hypofractionated PMRT groups, respectively. However, no other adverse events were observed. CONCLUSION: Although further follow-up is required, hypofractionated radiotherapy regimens for postoperative patients with breast cancer in East and Southeast Asian countries are effective and safe. In particular, the proven efficacy of hypofractionated PMRT indicates that more patients with advanced breast cancer can receive appropriate care in these countries. Hypofractionated WBI and hypofractionated PMRT are reasonable approaches that can contain cancer care costs in these countries. Long-term observation is required to validate our findings.

Defining the minimal clinically important difference in smartphone-based mobility after spine surgery: correlation of survey questionnaire to mobility data.

OBJECTIVE: Patient-reported outcome measures (PROMs) are the gold standard for assessing postoperative outcomes in spine surgery. However, PROMs are also limited by the inherent subjectivity of self-reported qualitative data. Recent literature has highlighted the utility of patient mobility data streamed from smartphone accelerometers as an objective measure of functional outcomes and complement to traditional PROMs. Still, for activity-based data to supplement existing PROMs, they must be validated against current metrics. In this study, the authors assessed the relationships and concordance between longitudinal smartphone-based mobility data and PROMs. METHODS: Patients receiving laminectomy (n = 21) or fusion (n = 10) between 2017 and 2022 were retrospectively included. Activity data (steps-per-day count) recorded in the Apple Health mobile application over a 2-year perioperative window were extracted and subsequently normalized to allow for intersubject comparison. PROMS, including the visual analog scale (VAS), Patient Reported Outcome Measurement Information System Pain Interference (PROMIS-PI), Oswestry Disability Index (ODI), and EQ-5D, collected at the preoperative and 6-week postoperative visits were retrospectively extracted from the electronic medical record. Correlations between PROMs and patient mobility were assessed and compared between patients who did and those who did not achieve the established minimal clinically important difference (MCID) for each measure. RESULTS: A total of 31 patients receiving laminectomy (n = 21) or fusion (n = 10) were included. Change between preoperative and 6-week postoperative VAS and PROMIS-PI scores demonstrated moderate (r = -0.46) and strong (r = -0.74) inverse correlations, respectively, with changes in normalized steps-per-day count. In cohorts of patients who achieved PROMIS-PI MCID postoperatively, indicating subjective improvement in pain, there was a 0.784 standard deviation increase in normalized steps per day, representing a 56.5% improvement (p = 0.027). Patients who did achieve the MCID of improvement in either PROMIS-PI or VAS after surgery were more likely to experience an earlier sustained improvement in physical activity commensurate to or greater than their preoperative baseline (p = 2.98 × 10-18) than non-MCID patients. CONCLUSIONS: This study demonstrates a strong correlation between changes in mobility data extracted from patient smartphones and changes in PROMs following spine surgery. Further elucidating this relationship will allow for more robust supplementation of existing spine outcome measure tools with analyzed objective activity data.

Characterizing and Improving Nomenclature for Reporting Lumbar Interbody Fusion Techniques.

OBJECTIVE: Lumbar interbody fusion (LIF) techniques have seen impressive innovation in recent years, leading to an expansion of the LIF lexicon. This study systematically analyzes LIF nomenclature in contemporary literature and proposes a standardized classification system for reporting LIF terminology. METHODS: A search query was conducted through the PubMed database using "lumbar fusion OR lumbar interbody fusion." A total of 1455 articles were identified, and 605 references to LIF were recorded. Following a systematic review of the terminology, we developed a LIF reporting guidelines that capture the existing LIF nomenclature while avoiding redundant or ambiguous terminology. RESULTS: The most referenced anatomical approaches were transforaminal (43.0%), followed by posterior (25.0%), lateral (19.7%), and anterior (10.9%). Overall, there were 72 unique ways to describe LIF. Unique prefixes were recorded by approach (posterior: 26; lateral: 13; anterior: 3). Forty unique prefixes/suffixes overlapped in their usage. "MI" (14.4%), "MIS" (38.1%), and "MISS" (0.6%) all referenced a minimally invasive approach. "O" (12.5%), "CO" (1.3%), and "TO" (1.3%) all described open techniques. "Endo" (0.6%), "Endoscopic-assisted" (1.3%), and "PE" (1.9%) all referenced endoscopic-assisted procedures. CONCLUSIONS: The current LIF nomenclature contains many unique LIF terms that were found to be inconsistently defined, redundant, or ambiguous. We propose the standardization of a 4-part naming system which highlights the crucial parts of LIF: (1) intraoperative repositioning, (2) patient position, (3) anatomical approach, and (4) orientation of the surgical corridor to the psoas muscles.

A Prospective Cohort Study of Radiation Exposure to a Spine Surgeon's Exposed Body Parts During Utilization of Intraoperative Radiation-based Imaging.

STUDY DESIGN: Prospective cohort study. SUMMARY OF BACKGROUND DATA: C-arm fluoroscopy and O-arm navigation are vital tools in modern spine surgeries, but their repeated usage can endanger spine surgeons. Although a surgeon's chest and abdomen are protected by lead aprons, the eyes and extremities generally receive less protection. OBJECTIVE: In this study, we compare differences in intraoperative radiation exposure across the protected and unprotected regions of a surgeon's body. METHODS: Sixty-five consecutive spine surgeries were performed by a single spine-focused neurosurgeon over 9 months. Radiation exposure to the primary surgeon was measured through dosimeters worn over the lead apron, under the lead apron, on surgical loupes, and as a ring on the dominant hand. Differences were assessed with rigorous statistical testing and radiation exposure per surgical case was extrapolated. RESULTS: During the study, the measured radiation exposure over the apron, 176 mrem, was significantly greater than that under the apron, 8 mrem (P = 0.0020), demonstrating a shielding protective effect. The surgeon's dominant hand was exposed to 329 mrem whereas the eyes were exposed to 152.5 mrem of radiation. Compared with the surgeon's protected abdominal area, the hands (P = 0.0002) and eyes (P = 0.0002) received significantly greater exposure. Calculated exposure per case was 2.8 mrem for the eyes and 5.1 mrem for the hands. It was determined that a spine-focused neurosurgeon operating 400 cases annually will incur a radiation exposure of 60,750 mrem to the hands and 33,900 mrem to the eyes over a 30-year career. CONCLUSIONS: Our study found that spine surgeons encounter significantly more radiation exposure to the eyes and the extremities compared with protected body regions. Lifetime exposure exceeds the annual limits set by the International Commission on Radiologic Protection for the extremities (50,000 mrem/y) and the eyes (15,000 mrem/y), calling for increased awareness about the dangerous levels of radiation exposure that a spine surgeon incurs over one's career.

Standardizing Lumbar Interbody Fusion Nomenclature.

STUDY DESIGN: This article is a research methodology study. OBJECTIVE: We summarize current ambiguities and inaccuracies regarding lumbar interbody fusion nomenclature and propose a standardized reporting method to improve the clarity of future research and communication among spine surgeons and researchers. SUMMARY OF BACKGROUND DATA: Lumbar interbody fusion techniques have seen an impressive degree of refinement over recent years. This innovation has ushered in a plethora of naming conventions for these new surgical approaches. Many of the current trends in naming lumbar fusion techniques are, however, redundant and contradictory, creating unnecessary confusion in the field. METHODS: Following an extensive literature review, we developed a 4-part naming convention that highlights the crucial features of lumbar fusion surgical procedures. RESULTS: Current literature regarding lumbar fusions is rife with inconsistent usage and privatization of terminology that can inadvertently result in ambiguous operative vocabulary, potentially compromising the accuracy of future research. We propose a 4-part naming system that highlights crucial features of lumbar interbody fusions, including (1) intra-operative repositioning, (2) patient position, (3) surgical technique, and (4) orientation of the surgical corridor to the psoas muscle. CONCLUSIONS: This study raises awareness of current inconsistencies in naming conventions and proposes a standardized system for improving the clarity of lumber interbody fusion terminology for the broader spine community. LEVEL OF EVIDENCE: Level V.

Virtual and Augmented Reality in Spine Surgery: A Systematic Review.

BACKGROUND: Augmented reality (AR) and virtual reality (VR) implementation in spinal surgery has expanded rapidly over the past decade. This systematic review summarizes the use of AR/VR technology in surgical education, preoperative planning, and intraoperative guidance. METHODS: A search query for AR/VR technology in spine surgery was conducted through PubMed, Embase, and Scopus. After exclusions, 48 studies were included. Included studies were then grouped into relevant subsections. Categorization into subsections yielded 12 surgical training studies, 5 preoperative planning, 24 intraoperative usage, and 10 radiation exposure. RESULTS: VR-assisted training significantly reduced penetration rates or increased accuracy rates compared to lecture-based groups in 5 studies. Preoperative VR planning significantly influenced surgical recommendations and reduced radiation exposure, operating time, and estimated blood loss. For 3 patient studies, AR-assisted pedicle screw placement accuracy ranged from 95.77% to 100% using the Gertzbein grading scale. Head-mounted display was the most common interface used intraoperatively followed by AR microscope and projector. AR/VR also had applications in tumor resection, vertebroplasty, bone biopsy, and rod bending. Four studies reported significantly reduced radiation exposure in AR group compared to fluoroscopy group. CONCLUSIONS: AR/VR technologies have the potential to usher in a paradigm shift in spine surgery. However, the current evidence indicates there is still a need for 1) defined quality and technical requirements for AR/VR devices, 2) more intraoperative studies that explore usage outside of pedicle screw placement, and 3) technological advancements to overcome registration errors via the development of an automatic registration method.

Combined L5-S1 Anterior Lumbar Interbody Fusion and Multilevel Lateral Lumbar Interbody Fusion in a Single-Stage Lateral Decubitus Position Using Fluoroscopy-Based Instrument Tracking System.

Anterior lumbar interbody fusion (ALIF), traditionally performed supine, allows for significant restoration of lumbar lordosis, disc height, and foraminal height in degenerative spine diseases; however, an iatrogenic injury to the viscera and the great vessels can have devastating consequences. Although lateral lumbar interbody fusion (LLIF) is an acceptable and minimally invasive alternative at the L5-S1 level, this approach is suboptimal because of a narrow surgical corridor limited by the iliac crest, common iliac artery and vein, and psoas. Furthermore, combining supine L5-S1 ALIF and lateral decubitus (LD) LLIF requires time-consuming patient repositioning.1,2 To maximize the advantages of both procedures in patients with disease spanning the lumbosacral junction, ALIF and LLIF can be performed in a single stage with the patient remaining in an LD position throughout. To improve the efficiency of this single-position procedure, a fluoroscopy-based instrument tracking system (TrackX Technology Inc., Hillsborough, North Carolina, USA) was used to navigate surgical tools during the procedure. We show this technique in a 43-year-old patient with medically intractable back and leg pain secondary to multi-level degenerative lumbar spondylosis. The patient consented to this procedure; all participants consented to publication of their images. This tracking system allowed for accurate and precise virtual projections of surgical instruments, thereby facilitating the identification of midline and proper trajectories to perform discectomy and implant placement, reducing the amount of intraoperative fluoroscopy use, and eliminating intraoperative computed tomography. To our knowledge, this is the first operative video showing a fluoroscopy-based instrument tracking system used in a combined single-position LD-ALIF and LD-LLIF.

Methods and Impact for Using Federated Learning to Collaborate on Clinical Research.

BACKGROUND: The development of accurate machine learning algorithms requires sufficient quantities of diverse data. This poses a challenge in health care because of the sensitive and siloed nature of biomedical information. Decentralized algorithms through federated learning (FL) avoid data aggregation by instead distributing algorithms to the data before centrally updating one global model. OBJECTIVE: To establish a multicenter collaboration and assess the feasibility of using FL to train machine learning models for intracranial hemorrhage (ICH) detection without sharing data between sites. METHODS: Five neurosurgery departments across the United States collaborated to establish a federated network and train a convolutional neural network to detect ICH on computed tomography scans. The global FL model was benchmarked against a standard, centrally trained model using a held-out data set and was compared against locally trained models using site data. RESULTS: A federated network of practicing neurosurgeon scientists was successfully initiated to train a model for predicting ICH. The FL model achieved an area under the ROC curve of 0.9487 (95% CI 0.9471-0.9503) when predicting all subtypes of ICH compared with a benchmark (non-FL) area under the ROC curve of 0.9753 (95% CI 0.9742-0.9764), although performance varied by subtype. The FL model consistently achieved top three performance when validated on any site's data, suggesting improved generalizability. A qualitative survey described the experience of participants in the federated network. CONCLUSION: This study demonstrates the feasibility of implementing a federated network for multi-institutional collaboration among clinicians and using FL to conduct machine learning research, thereby opening a new paradigm for neurosurgical collaboration.