bluuebunny/crossref_metadata_2025_split huggingface dataset:
1078 Performance of Improved Forms of Demineralized Bone Fiber Allografts in Rabbit Posterolateral Spine Fusion Model
Authors: Scarborough Nelson , Barnes Brian , Khan Safdar 
Published: March 2024

INTRODUCTION:
Biologic fusion is often critical for successful spine procedures. Autograft remains the Gold Standard bone graft due to osteogenic properties but has limitations in practice. New bone graft forms that efficiently incorporate autograft or bone marrow aspirate (BMA) and provide osteoinductive and osteoconductive properties were evaluated in the current study. Grafts were made using demineralized bone fibers (DBF) produced by a patented method that provides long fibers that can effectively entangle autograft and be formed into open cylinders (PAK) that contain and prevent autograft migration and absorb BMA.

METHODS:
DBF was produced from rabbit cortical bone using the same processes as human clinical product. Pak grafts were made with 1.5cc Fibers formed into a cylinder with 1.5cc volume. Implants into the rabbit PLF model were harvested after 8 weeks and evaluated for fusion by manual palpation and x-rays.

RESULTS:
All graft forms demonstrated robust new bone formation. Each group demonstrated high fusion rates. Across the groups 10/11 levels were 100% fused (91%) with the remaining 1/11 being 95% reduced motion (functionally fused). Note radiolucency of Group 3 at post-op and appearance of new bone at 8 weeks.

CONCLUSIONS:
The new graft forms demonstrated robust bone formation and fusion in PLF model. The DBF Fibers provided excellent entanglement of autograft to prevent migration. The PAK form eliminated autograft migration, and absorbed BMA providing osteogenesis to the osteoconductive and osteoinductive graft.
1081 Risk Factors for Long Term Opioid Use After Elective Lumbar Spine Surgery: A MSSIC Study
Authors: Telemi Edvin , Mansour Tarek R. , Springer Kylie , Hu Jianhui , Schultz Lonni , Nerenz David , Schwalb Jason M. , Abdulhak Muwaffak , Brennan Matthew , Kim Enoch Gene , Margabandu Pavithra , Chang Victor W. 
Published: March 2024

INTRODUCTION:
Long-term opioid use after elective lumbar spine surgery is a significant concern, given the current opioid epidemic and its impact on public health. Identifying risk factors for long-term opioid use after spine surgery is crucial in developing effective interventions to reduce the incidence of opioid dependence in this patient population.

METHODS:
A retrospective analysis of patient data was conducted using the Michigan Spine Surgery Improvement Collaborative (MSSIC) registry. Patients who underwent elective lumbar spine surgery between March 2018, and September 2021, were included, resulting in a total of 3599 patients at one year and 966 patients at two years follow-up. Poisson generalized estimating equation models were used for multivariate analyses.

RESULTS:
A total of 493 (13.7%) and 137 (14.2%) patients were still using opiates at one-year and two-years post-surgery respectively. Discharge morphine milligram equivalents (MMEs), baseline PROMIS PF functional scores, baseline pain scores, age, gender, education level, pre-operative opioid use, and not achieving the minimal clinically important difference (MCID) in PROMIS PF scores at follow-up were significantly associated with long-term opioid use. Specifically, pre-operative opioid use had the strongest association with opioid use at one year (IRR = 2.83, CI: 2.40-3.34, p < 0.001) and two years (IRR = 3.79, CI: 2.53-5.68, p < 0.001). Additionally, not achieving MCID in PROMIS scores at follow-up was strongly associated (IRR = 2.00, CI: 1.72-2.32, p < 0.001 and IRR = 2.18, CI: 1.64-2.91, p < 0.001) with opioid use at both time points (1-year and 2-year respectively).

CONCLUSIONS:
Pre-operative opioid use and not achieving MCID in PROMIS scores at follow-up were the strongest predictors of long-term opioid use after elective lumbar spine surgery. Identifying these risk factors can help clinicians target interventions to reduce opioid use in at-risk patients and improve postoperative outcomes.
1086 Surgical Posture With Microscopic Versus Exoscopic Visualization in Anterior Cervical Procedures
Authors: Kusyk Dorian , Jeong Seung , Fitzgerald Ethan , Williamson Richard Wiley , Kwong-Tak Yu Alexander 
Published: March 2024

INTRODUCTION:
Workplace posture has long been associated with back and neck pain, and surgeons are not exempt. Though intraoperative surgeon posture has progressively improved with the visualization of the operative microscope, surgeons nonetheless continue to sustain deviated postures during operations which may result in increased rates of neck and back pain. The surgical exoscope is designed to improve surgical ergonomics. This study aims to quantify the difference in posture during standard anterior cervical spine procedures when performed with the aid of an operative microscope versus an exoscope.

METHODS:
This is a prospective cohort study utilizing the MetaWare MetaMotion S device placed at the surgeon’s cervicothoracic junction to measure Euler angles of upper thoracic spine during each case. Primary outcome was the percentage of time spent with greater than 10deg deviation from a surgeon’s baseline posture while using either the microscope or the exoscope. Additional metrics were analyzed for average deviation from baseline for each axis, as well was percentage of operative time spent with the microscope or the exoscope.

RESULTS:
Overall, 37 anterior cervical procedures were recorded, 18 performed with an exoscope and 19 with a microscope. Surgeons spent significantly more time in a deviated posture with the operative microscope than with the exoscope (32% vs 8% with x-axis >10 deg, p < 0.005; 20% vs 6% with y-axis >10 deg, p < 0.05). This is also reflected with significant differences in the average deviation in the x- and y- axis while under scope.

CONCLUSIONS:
Utilizing the exoscope for anterior cervical spine procedures allowed for less time spent in deviated posture.
111 Interspinous Process Device Utilization and Reimbursement Vary by Provider Specialty and Care Setting
Authors: Jiang Kelly , Gong Jung Ho , Azad Tej D. 
Published: March 2024

INTRODUCTION:
Interspinous process devices (IPDs) are a popular less invasive treatment option for lumbar degenerative disease. Studies suggest they may yield initial symptomatic relief but are not better than traditional surgery in improving function or quality of life and may increase reoperation and costs. Ideal indications remain contested.

METHODS:
Centers for Medicare and Medicaid Services Physician/Supplier Procedure Summary data sets (2017-2020) were queried by CPT codes for lumbar interlaminar/interspinous process stabilization/distraction devices without fusion. Utilization rates were normalized per 10,000 lumbar fusions.

RESULTS:
IPD utilization increased by 329% from 2017-2020. Percutaneous IPD utilization increased to 31.8 (+1,267%), while open procedures decreased to 4.4 (-27%). Pain management/anesthesia placed the majority of IPDs and increased utilization the most (27.4, +1,387%). Physical medicine and rehabilitation (PM&R) had the second-highest rate of utilization (3.5, +1,492%). Neurosurgery (2.3, -15%) and orthopedics (0.7, -63%) decreased utilization. Ambulatory surgical centers (ASCs) increased utilization the most (25.8, +907%). Outpatient procedures increased (9.2, +162%), while inpatient procedures decreased (1.2, -49%). IPD reimbursements decreased to $400 (-44.6%), with decreasing trends in percutaneous ($364, -28.6%) and open placement ($776, -6.8%). Reimbursements were highest for orthopedics ($800, +0.6%) and lowest for pain management/anesthesiology ($362, -26.7%). Reimbursements decreased across all settings, especially outpatient (-48.8%) and inpatient (-35.9%).

CONCLUSIONS:
Despite uncertainty of indications for IPDs, utilization increased by 329% when normalized to lumbar fusions to account for changes in disease prevalence. IPDs are increasingly placed by PM&R and pain management in ASCs and outpatient settings. Utilization does not seem to be driven by reimbursement rates. It is unknown how the rapid increase in IPDs has affected clinical outcomes. Given the magnitude of increased utilization and limited data on the safety and efficacy of IPDs, closer examination of indications is warranted.
112 Impact of COVID-19 on Neurosurgical Utilization and Reimbursement
Authors: Rallo Michael Stephen , Nanda Anil , Menger Richard P. 
Published: March 2024

INTRODUCTION:
The COVID-19 pandemic required significant adaptations in healthcare operations to preserve limited resources and mitigate viral spread. This included the postponement of non-emergent services, including elective surgical procedures, in the Spring/Summer of 2020. Additionally, patients may have avoided or delayed medical care even after the mandatory postponement due to fear of infection.

METHODS:
We analyzed public data summarizing neurosurgical services provided to Medicare beneficiaries. Annual number of services rendered, beneficiaries treated, and payments received by neurosurgeons were compared between 2019 and 2020 via Students’ T-test and Wilcoxon Rank-Sum tests. Procedures were categorized by location, pathology, and/or approach to identify patterns in the types of procedures most heavily impacted. Pearson's linear regression was used to determine the relationship between the stringency of Covid-19 restrictions and the change in services.

RESULTS:
From 2019 to 2020, there was a 12.27% decrease in the aggregate number of services rendered by neurosurgeons corresponding to a 12.48% decrease in total Medicare payment. In a matched cohort of 4,649 neurosurgeons active in both 2019 and 2020, the average number of annual services per neurosurgeon declined by 12.40% with a concomitant decrease in payment by 12.77%. This corresponded to an average per-neurosurgeon loss of $17,455.43 in Medicare-related income. Nationally, functional, sellar/parasesellar, and open cerebrovascular surgeries exhibited the largest reduction in volume (all >20%). In contrast, endovascular procedures only declined by 5.5%. There was a weak but significant trend toward larger reduction in volume in states with more stringent Covid-19 restrictions (R = -0.357, p = 0.010).

CONCLUSIONS:
Neurosurgeons experienced significant reductions in case volume and income during the first year of the Covid-19 pandemic. The magnitude of impact appears to be influenced, at least in part, by the stringency of state-level restrictions.
1130 Anatomical Features Predicting Outcome From Stereotactic Laser Amygdalohippocampotomy
Authors: Zajner Chris , Lau Jonathon , Isbaine Faical , Laxpati Nealen , Gross Robert E. 
Published: March 2024

INTRODUCTION:
Stereotactic laser amygdalohippocampotomy (SLAH) is a novel procedure which is effective and safe for the treatment of temporal lobe epilepsy. Optimal operative ablation location and extent, however, is uncertain, as are the neuroanatomical features guiding successful ablations.

METHODS:
Patients treated with SLAH for MTS at Emory University between 2011 and 2019 (n = 65) were considered in this retrospective study. Post-procedure T1 MRI scans of patients were used to create manual segmentations of the ablation region of each patient. Ablations were assessed in relation to 1) whether they crossed the coronal plane of the lateral mesencephalic sulcus (LMS), 2) the extent to which the ablation extended posterior to the LMS, and 3) extent of ablation of the uncus. Wilcoxon ranked-sign test was performed for each variable between groups of patients with Engel score 1 versus Engel score 2-4.

RESULTS:
Distance of ablation past the LMS was not different between Engel class 1 (mean 6.32 ± 4.16 mm), and Engel class 2-4 (7.93 ± 3.75 mm) (p = 0.099). Ratio of ablations extending posterior to the LMS was 0.82 (SD = 0.39) in Engel 1, and 0.90 (SD = 0.30) in Engel 2-4 (p = 0.370). Volume of ablation showed little correlation with outcome, with average ablation of Engel 1 = 6064 ± 2128 mm3, Engel 2-4 = 5828 ± 3031 mm3, and no significant difference with Wilcoxon ranked-sign test (p = 0.239). Ablation of the uncus showed a strong association with better surgical outcome, with ratio of uncus ablation for Engel 1 at 0.71(SD = 0.31), and Engel 2-4 at 0.37 (SD = 0.36); p < 0.001).

CONCLUSIONS:
Larger ablation alone was not associated with better surgical outcomes. Ablation of the uncus was shown to result in better outcomes. Contrary to current practice, extension of SLAH ablation posterior to the lateral mesencephalic sulcus did not demonstrate improved post-operative outcomes.
114 Compliance with Federal Price Transparency Rules at US Hospitals With Neurosurgical Training Programs
Authors: Larsen Alexandra Giantini , Pandey Abhinav , Tata Nalini , Newman W. Christopher 
Published: March 2024

INTRODUCTION:
The Centers for Medicare & Medicaid Services implemented federal requirements on January 1st, 2021 that require hospitals to provide a list of payer-negotiated prices in a machine-readable file.

METHODS:
We performed a cross-sectional analysis in March of 2023 of 116 US hospitals associated with a neurosurgical training program to assess compliance with the new federal requirements by searching “price transparency” or “standard charges” with associated hospital on the internet to download machine readable files. The payer-negotiated price for 11 common neurosurgical procedures based on CPT codes for 4 insurance companies were collected (Aetna,Anthem/BCBS,United,Medicare). Pricing using DRG codes were excluded given the range of neurosurgical procedures that are encompassed by a specific DRG code.

RESULTS:
92/116 (79.3%) hospitals were compliant with the requirement for machine-readable file with payer-negotiated prices. 45/92 (48.9%) used DRG codes. For the common neurosurgical procedures, hospitals had negotiated price available for at least one insurance company with average private insurance cost and average Medicare costs as follows: ventriculoperitoneal shunt (21/92;$10,698;$1,919), lumbar laminectomy (20/92;$10,343;$4,460), lumbar microdiscectomy (31/92;$9,374;$5,026), anterior cervical discectomy and fusion (28/92;$11,544;$9,859), deep brain stimulator with microelectrode recording (15/92;$10,510;$3,616), craniotomy for tumor (14/92;$6,951;$2,361), stereotactic radiosurgery for brain (18/92;$22,409;$7,362) and spine (14/92;$14,242;$3,306), intrathecal pump placement (31/92;$7,139;$5,064), intracranial aneurysm endovascular treatment (14/92;$9,452;$3352), and diagnostic angiogram (46/92;$11,295;$5,867).

CONCLUSIONS:
While hospital compliance with federal requirement for machine readable files with payer-negotiated prices was high, availability of payer-negotiated prices for 4 major insurance types across 11 common neurosurgical procedures based on CPT code was sparce. Overall, meaningful conclusions on procedural related cost for elective procedures will be difficult for patients to make due to the unintelligible format of data and a lack of reporting of cost per CPT code in a comprehensive manner.
117 Standardizing Wearable-based Real-life Physical Activity Monitoring in Patients Undergoing Surgery for Degenerative Lumbar Disorders
Authors: Maldaner Nicolai , Tang Megan , Leung Christopher , Desai Atman , Tomkins-Lane Christy , Zygourakis Corinna Clio 
Published: March 2024

INTRODUCTION:
Assessment of function in patients with degenerative thoracolumbar disorders (DTD) has traditionally relied solely on the patient’s subjective perception of disability. There is a clear need to better understand an objective measure of physical activity impairment in this patient cohort.

METHODS:
This analysis is part of the Stanford SpineTrak study, a RCT to assess the feasibility of using a commercially available smartwatch (AppleWatch) to monitor outcome in patients with DTD. Mean preoperative physical activity 2 weeks before surgery was expressed as raw step count, as well as in standardized z-scores that wre referenced to age- and sex-specific values of a control population from a large public database. Step counts were assessed for convergent validity with established patient-reported outcome measures (PROMs) and impairment in activity was stratified into performance groups based on z-score cut-off values.

RESULTS:
Of 67 patients with DTD, 65 patients (62% female) with a mean age (SD) of 63.8 (12.8) years were available for analysis with a mean (SD) daily step count of 5215 (3868). Physical activity showed significant correlation with the ODI (r = 0.28, 95% CI -0.49-0.03), SF36-PCS (r = -0.34, 95% CI 0.11-0.54) and PROMIS-PF (r = -0.48, 95% CI 0.27-0.65). No, Mild, moderate, and severe impairment in activity performance were defined as corresponding z-scores of >0, 0 to -0.99, -1 to -1.99 and = -2, accounting for 20%, 29%, 43% and 8% of the study population. Each 1-step increase in activity impairment resulted in increased subjective disability as measured by the ODI, SF36-PCS and PROMIS-PF (all < 0.05).

CONCLUSIONS:
This study establishes a new wearable-based objective measure of real-life physical activity as well as corresponding standard scores that allow for a direct comparison of test results between individual patients and different study populations.
120 Outcome Related Thresholds of Near Infrared Spectroscopy Based Cerebrovascular Reactivity Metrics in Moderate Severe TBI: A Canadian High Resolution-TBI (CAHR-TBI) Cohort Study
Authors: Gomez Alwyn Titus , Tas Jeanette , Aries Marcel , Griesdale Donald , Froese Logan , Thelin Eric , Raj Rahul , Gallagher Clare Naomi , Bernard Francis , Kramer Andreas H. , Zeiler Frederick 
Published: March 2024

INTRODUCTION:
Dysfunctional cerebrovascular reactivity (CVR)/autoregulation contributes to secondary injury following traumatic brain injury (TBI). Currently, monitoring of CVR relies on intracranial pressure (ICP) monitoring and has known thresholds at which outcomes worsen. Interest has shifted to less invasive near infrared spectroscopic (NIRS) regional cerebral oxygen saturation (rSO2) based measures of CVR. However, threshold levels at which outcomes worsen have not yet been determined for these indices.

METHODS:
A retrospective multi-institutional cohort study utilizing the CAnadian High Resolution TBI (CAHR-TBI) Research Collaborative database was performed. The cohort included TBI patients with ICP, arterial blood pressure (ABP), and rSO2 monitoring treated in adult intensive care units (ICU). COx (using rSO2 and cerebral perfusion pressure) as well as COx_a (using rSO2 and ABP) were calculated for each subject as the rSO2 based indices of CVR. 2 x 2 tables were created grouping patients by alive/dead and favorable/unfavorable outcomes at various thresholds of COx and COx_a as well as rSO2 itself. Chi-square values were calculated and the threshold producing the highest value was identified as providing the best discriminative value.

RESULTS:
A total of 129 patients were included. For both COx and COx_a an optimal threshold value of 0.2 was identified for both survival (χ2 = 9.57, p = 0.0020; χ2 = 13.04, p = 0.0003 respectively) and favorable outcomes (χ2 = 5.98, p = 0.0145; χ2 = 8.94, p = 0.0028 respectively) with values above this associated with worse outcomes. Notably, there was no identifiable threshold for raw rSO2 values at which outcomes were identified to worsen.

CONCLUSIONS:
In this multi-institutional cohort study, COx and COx_a were found to have a uniform threshold of 0.2, above which clinical outcomes worsened. This study lays the groundwork to transition to less invasive means of continuously measuring CVR.
1229 Leveraging Machine Learning for Pre-operative Prediction of Supralesional Ablation in Laser Interstitial Thermal Therapy (LITT) for Brain Tumors
Authors: Bhatia Shovan , Merenzon Martin Andres , Levy Adam , Rivera Cameron , Lu Victor M. , Chand Daggubati Lekhaj , Luther Evan , Shah Ashish H. , Komotar Ricardo Jorge , Ivan Michael E. 
Published: March 2024

INTRODUCTION:
Although maximizing the extent of ablation (EOA) following laser interstitial thermal therapy (LITT) can improve outcomes in patients with brain tumors, the pre-operative factors that predict a supralesional ablation (EOA >100%) remain unclear.

METHODS:
A retrospective study of patients with glioblastoma, metastasis, or radiation necrosis receiving LITT at a tertiary care referral center between 2013 to 2023 was conducted. Using the EOA >100% as a primary outcome, several clinical and radiographic pre-operative factors were evaluated. Five ML models, Decision Trees, Random Forest, Gradient Boosting, XGBoost, and AdaBoost, were trained using an 80/20 training/testing split and 5-fold cross validation. The models were optimized using hyperparameter tuning and evaluated against traditional logistic regression. The area under the receiver operating characteristic curve (AUC-ROC) was used to evaluate model performance. The optimal pre-operative volume cutoff for constituting an EOA >100% was also explored.

RESULTS:
201 patients were included in the final cohort. Multivariate logistic regression showed that lower pre-operative volume (p < 0.001) and deep-seated lesions (p = 0.041) have a greater likelihood to undergo a supralesional ablation. Of the five ML models analyzed, Random Forest had the highest F1-score of 0.889, and XGBoost had the highest AUC-ROC of 0.74. Additionally, Random Forest (p = 0.02), Gradient Boosting (p < 0.001) and XGBoost (p = 0.01) showed statistically improved predictive performance compared to logistic regression. Features of importance were pre-operative volume, deep-seated lesions, and ellipsoid ratio. The pre-operative lesion volume cutoff for achieving an EOA >100% was 4.38 cc.

CONCLUSIONS:
This study shows the improved predictive ability of ML models over a traditional regression model in determining pre-operative factors for a supralesional ablation of brain tumors following LITT. Notably, the ML models identified pre-operative tumor volume, deep-seated tumors, and ellipsoid tumors as important factors, which could optimize treatment decisions and patient outcomes.