bluuebunny/crossref_metadata_2025 huggingface dataset:
How social media sharing drives consumption intention: the role of social media envy and social comparison orientation
Authors: Liu Dege , He Bin , Feng Ruan , Huang Xiaojun , Liu Gaoqiang
Published: March 2024

Background

Social media benign envy, an upward comparison-based and painful emotions associated with the motivation to improve oneself, has attracted increasing attention from researchers due to its ubiquitous and significant impact on social network users’ intentions and behavior. However, the results of previous studies on whether material or experiential consumption is more likely to cause social media envy (treated as a single construct) have been inconsistent, and there is a lack of research on what triggers social media users to experience more intense benign envy and thus inspiring their consumption intentions. The purpose of this study is to investigate how the type and luxuriousness of shared consumption and viewer’s social comparison orientation jointly affect social media users’ consumption intentions through benign envy.

Methods

A 2 (type of consumption sharing: experiential vs. material) × 2 (luxuriousness of consumption sharing: luxury vs. non-luxury) × 2 (social comparison orientation: high vs. low) mixed-design experiment was conducted to test theoretical model with data from 544 undergraduates in China. SPSS 26.0 and the Process macro were used to test the model.

Results

The results revealed that luxury experiential consumption information shared on social media triggered more benign envy compared with other types of shared consumption information. When social media users shared non-luxury consumption, experiential consumption was more likely to inspire benign envy among users with high social comparison orientation than material consumption. However, when luxury consumption was shared, benign envy acted as a mediator between purchase type and participants’ purchase intention regardless of whether participants’ social comparison orientation was high or low.

Conclusion

This study revealed that whether and how social comparison orientation of social media users who read the shared content influences the mechanism by which the type of consumption sharing on social media affects social media users’ consumption intentions through benign envy as a mediator is dependent on the luxuriousness of the shared consumption. The findings not only provide new insights for researchers to better understand social media envy and the underlying psychological mechanism for social media readers’ consumption intention, but also have practical implications for practitioners.
Novel formulated alumina-silica hybrid sol for the entire consolidation of waterlogged decayed ivory from Sanxingdui ruin site
Authors: Liu Yusong , Xu Qingmeng , Li Sifan , Xie Zhenbin , Li Qiang , Luo Hongjie , Ji Shidong
Published: March 2024

Large amount of ivory was excavated from Sanxingdui site which was waterlogged, severely degraded and in urgent need for conservation. There has been much effort for the conservation of waterlogged ivory by scientists. However, due to a lack of appropriate conservation material and the need to use non-destructive methods, no satisfactory results have been achieved previously. In this work, a novel formulated water-based Al–Si hybrid sol of size about 20 nm was prepared and introduced through a quasi-dynamic equilibrium method to waterlogged ivory tusk for the purpose of conservation. Good conservation performance could be achieved, since Al–Si sol gradually permeates into the interior of the ivory, distributes homogeneously and connects the loose components of ivory. Samples treated with appropriate amount of Al–Si sol displayed satisfactory compressive strength and porous intact structure. It was found that the fluidity of Al–Si sol had a significant influence on the conservation effect. Moreover, Al–Si sol not only consolidated HAP but also worked well on the soil embedded in unearthed ivory, which was beneficial to conserve ivory intactly. Slightly negatively charged Al–Si hybrid gel could interact with ivory matrix through multiple interactions including van der Waals force, electrostatic interaction, chemical and hydrogen bonding.
New observational projects in New Zealand for studying radiation belt loss processes in the deep inner magnetosphere: instrumentation, operation by solar power and initial results
Authors: Obana Yuki , Sakaguchi Kaori , Nosé Masahito , Hosokawa Keisuke , Jaquiery Peter , Saita Satoko , Shiokawa Kazuo , Connors Martin , Kadokura Akira , Nagatsuma Tsutomu , Petersen Tanja
Published: March 2024

This paper describes the instrumentation and the first results of an upper atmospheric observing project conducted in New Zealand. We operate an all-sky aurora camera and a 64-Hz sampling induction magnetometer at Middlemarch, as well as 1-Hz sampling fluxgate magnetometers which have been operative at three stations in New Zealand, Middlemarch, Eyrewell and Te Wharau. Green and red auroras corresponding to the 557.7 nm and 630.0 nm emissions, respectively, were observed on the night of 5 August 2019. Pc1 pulsations were observed in the frequency range of ~ 0.2–1 Hz before and after a small (minimum Dst = − 40 nT) geomagnetic storm during 4–6 October 2020. Before the geomagnetic storm, Pc1 pulsations with several center frequencies were observed regardless of local time. During the recovery phase, an IPDP (interval of pulsations of diminishing period) type of Pc1 and four subsequent intervals of Pc1s were detected. The Ionospheric Alfvén Resonator (IAR) was also identified with spectral resonance structures during this magnetic storm. Lower harmonic modes of the IAR were present throughout the local nighttime, but higher harmonic modes with frequency of 5–15 Hz seemed to disappear at the onset time of substorms. This is the first report of the IAR at such a high frequency range and this is the first IAR observation in the southern hemisphere. Examples of applying cross-phase analysis to observation data of fluxgate magnetometers are also given.

Graphical Abstract
Tracheostomy for the pediatric patient with fibrodysplasia ossificans progressiva: a case report
Authors: Kobayashi Megumi , Hirai Misako , Suzuki Makoto , Sasaki Akira
Published: March 2024

Background

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare connective tissue disease characterized by subsequent ossification of skeletal muscles, tendons, ligaments, and other fibrous tissues. The ossification of these tissues progresses during childhood and leads to limb and trunk deformities. Since any surgery may trigger subsequent ossification, it is relatively contraindicated for patients with FOP. In this report, we describe our experience in performing tracheostomy in a pediatric patient with FOP who developed a restrictive respiratory disorder due to progressive deformity of the trunk.

Case presentation

A 12-year-old boy, diagnosed with FOP at the age of one, was referred for a tracheotomy after requiring 2 months of oral intubation and mechanical ventilation due to severe deformity-induced dyspnea. After changing from oral intubation to nasal intubation, we carefully considered the indications and benefits of tracheostomy in patients with FOP. Eventually, tracheostomy was successfully performed using our surgical design: creating a skin incision at the level of the cricoid cartilage that can always be identified, creating inverted U-shaped incision on the anterior tracheal wall to make a flap, and suturing the entire circumference of the tracheotomy and skin. One month after the surgery, he regained normal breathing and pronunciation and returned to school. The patient showed no unfavorable postoperative outcomes over a 4-year follow-up period.

Conclusions

Tracheostomy in our pediatric case of FOP required careful perioperative management. However, it could effectively improve the patient’s quality of life.
Ectopic bile duct concomitant with gastric ulcer hemorrhage: report of a case
Authors: Nagasawa Yuiko , Ohta Masayuki , Shitomi Yuki , Satoh Hiroshi , Aramaki Masanori
Published: March 2024

Background

An ectopic bile duct opening into the stomach is a rare congenital anomaly of the biliary system, and thus, there are few case reports with gastric ulcer hemorrhage. Herein, we presented a case of ectopic bile duct concomitant with gastric ulcer hemorrhage.

Case presentation

A 75-year-old woman was referred to our hospital because she repeatedly vomited blood and had melena. Endoscopic hemostasis was attempted for hemorrhage from a gastric ulcer located on the anterior wall of the antrum. However, the bleeding was difficult to stop, and a laparoscopic distal gastrectomy was performed. Her postoperative course was uneventful. Pathological examination revealed that the bleeding point was an ectopic bile duct. In retrospect, an annual endoscopy performed at her family clinic had revealed a bulge in the same portion of the stomach. Exposure to bile acids from an ectopic bile duct opening can cause gastric mucosal damage and ulceration.

Conclusions

Ectopic bile ducts opening into the stomach can cause gastric ulcer and hemorrhage. Hemorrhage from a submucosal ridge with ulcer in the stomach may be rarely related to the presence of ectopic bile ducts.
Working from home is here to stay, but how does it affect workplace learning?
Authors: Morlet Guillaume M. A. , Bolli Thomas
Published: March 2024

This paper analyses how working from home affects workplace learning in terms of theoretical and practical knowledge during COVID19. We employ panel data gathered in monthly surveys of respondents in training companies between October 2020 and March 2022 to investigate this question. Apprentices in Switzerland are our case study. We address potential endogeneity concerns in two ways. First, we exploit variation across survey respondents and time in two-way fixed effects models. Second, we pursue an instrumental variable “shift-share”-type approach that leverages how occupations react to exogenous changes in working from home regulations. The results suggest that working from home has a significantly negative impact on practical knowledge but not theoretical knowledge, relative to frequenting the workplace. We do not find significant heterogeneity across company size. Similarly, our results do not vary significantly between occupations in which working from home is relatively more or less prevalent. Our findings remain robust to a wide range of robustness checks. Our evidence-based recommendations aim to preserve the acquisition of knowledge through workplace training.
Mass transfer analyses of reactive boundary schemes for lattice Boltzmann method with staircase approximation
Authors: Tong Zi-Xiang , Li Ming-Jia , Du Yanxia , Yuan Xianxu
Published: March 2024

Lattice Boltzmann (LB) methods with reactive boundary conditions are widely used in pore-scale simulations of dissolution and ablation processes. The staircase approximation of curved boundary is often employed because of its simplicity in handling solid structure changes. In this work, the mass transfer of two typical LB reactive boundary schemes are analyzed for the staircase boundary. The Type I boundary scheme is based on relations of local distribution functions and a wet-node boundary mesh. The Type II boundary scheme adopts the half-way bounce-back scheme. Boundary concentrations are determined by finite difference, and a link-wise boundary mesh is used. The analyses demonstrate that for straight boundaries, both the boundary schemes have accurate mass transfer rates, which means the mass transfer calculated by exchanges of distribution functions is the same as that calculated by reaction rates. For curved boundaries with staircase approximation, including interfacial normal directions in the Type I boundary scheme can provide accurate mass transfer for inclined straight boundaries. However, if the staircase boundary geometry is used directly without normal directions, the reaction rate will be overestimated. One-dimensional and two-dimensional reaction-diffusion processes with dissolution are simulated to validate the analyses. Both the boundary schemes work well for one-dimensional simulations. For two-dimensional simulations, the Type II boundary scheme significantly overestimates the reaction rate, and stronger artificial anisotropic effects are observed. The Type I boundary scheme with normal directions has better performance, but error still exists.
Improving healthcare quality by unifying the American electronic medical report system: time for change
Authors: Kumari Roopa , Chander Subhash
Published: March 2024

Background

In recent years, innovation in healthcare technology has significantly improved the efficiency of the healthcare system. Advancements have led to better patient care and more cost-effective services. The electronic medical record (EMR) system, in particular, has enhanced interoperability and collaboration across healthcare departments by facilitating the exchange and utilization of patient data. The COVID-19 pandemic further accelerated this trend, leading to a surge in telemedicine services, which rely on electronic communication to deliver healthcare remotely.

Main body

Integrating artificial intelligence (AI) and machine learning (ML) in healthcare have been instrumental in analyzing vast data sets, allowing for identifying patterns and trends that can improve care delivery and pinpoint potential issues. The proposal of a unified EMR system in the USA aims to capitalize on these technological advancements. Such a system would streamline the sharing of patient information among healthcare providers, improve the quality and efficiency of care, and minimize the likelihood of errors in patient treatment.

Conclusion

A unified electronic medical record system represents a promising avenue for enhancing interoperability within the US healthcare sector. By creating a more connected and accessible network of patient information, it sets the stage for a transformation in healthcare delivery. This change is imperative for maintaining the momentum of progress in healthcare technology and realizing the full potential of recent advancements in patient care and system efficiency.
Investigation of mechanical properties of high-performance concrete via optimized neural network approaches
Authors: Wang Xuyang , Cong Rijie
Published: March 2024

In this paper, an artificial intelligence approach has been employed to analyze the slump and compressive strength (CS) of high-performance concrete (HPC), focusing on its mechanical properties. The importance of assessing these critical concrete characteristics has been widely acknowledged by experts in the field, leading to the development of innovative methods for estimating parameters that typically require laboratory testing. These intelligent techniques improve the accuracy of mechanical property predictions and reduce the resource-intensive and costly nature of experimental work. The radial basis function neural network (RBFNN) is the foundational model for predicting the mechanical attributes of various HPC mixtures. To fine-tune the RBFNN’s performance in replicating the mechanical properties of HPC samples, two optimization algorithms, namely the Golden Eagle Optimizer (GEO) and Dynamic Arithmetic Optimization Algorithm (DAOA), have been employed. In this manner, both RBGE and RBDA models were trained using a dataset comprising 181 HPC samples that included superplasticizers and fly ash. The results show that DAOA has significantly improved the base model’s predictive capability, achieving a higher correlation with a value R2 of 0.936 when estimating slump. Furthermore, RBDA exhibited a more favorable root mean square error (RMSE) in predicting compressive strength compared to RBGE, with a notable 16% difference. Ultimately, both integrated models demonstrated their effectiveness in accurately modeling the mechanical properties of HPC.
The 13C Glucose Breath Test Accurately Identifies Insulin Resistance in People With Type 1 Diabetes
Authors: Mertens Jonathan , Roosens Laurence , Braspenning Rie , Vandebeeck Joeri , Francque Sven , De Block Christophe
Published: March 2024

Objective

This study investigated whether the delta-over-baseline of exhaled 13CO2 (Δ13CO2), generated from a 13C glucose breath test (13C-GBT), measured insulin resistance (IR) in people with type 1 diabetes, using the hyperinsulinemic-euglycemic clamp (HEC) as a reference method. The secondary objective was to compare the 13C-GBT with the estimated glucose disposal rate (eGDR).

Methods

A 40 mU/m2/min HEC and 2 separate 13C-GBTs (euglycemic with insulin bolus and hyperglycemic without bolus) were consecutively performed in 44 adults with type 1 diabetes with varying body compositions. eGDR was calculated based on hemoglobin A1c (HbA1c), presence of hypertension, and waist circumference.

Results

The mean glucose disposal rate (M-value) was 5.9 ± 3.1 mg/kg/min and mean euglycemic Δ13CO2 was 6.4 ± 2.1 δ‰, while median eGDR was 5.9 [4.3-9.8] mg/kg/min. The hyperglycemic Δ13CO2 did not correlate with the M-value, while the euglycemic Δ13CO2 and the M-value correlated strongly (r = 0.74, P < .001). The correlation between M-value and eGDR was more moderate (Spearman's rho = 0.63, P < .001). Linear regression showed an association between Δ13CO2 and M-value, adjusted for age, sex, and HbA1c ]adjusted R² = 0.52, B = 1.16, 95% confidence interval (CI) .80-1.52, P < .001]. The area under the receiver-operator characteristics curve for Δ13CO2 to identify subjects with IR (M-value < 4.9 mg/kg/min) was 0.81 (95% CI .68-.94, P < .001). The optimal cut-off for Δ13CO2 to identify subjects with IR was ≤ 5.8 δ‰.

Conclusion

Under euglycemic conditions, the 13C-GBT accurately identified individuals with type 1 diabetes and concurrent IR, suggesting its potential as a valuable noninvasive index.

Clinical Trial Identifier: NCT04623320
102 BB-031 Recanalizes MCAO and Reduces Inflammation in Canine Model of LVO Stroke
Authors: Carfora Arianna , Wheeler Debra , Huttinger Allyson , Kini Aarushi , Mandybur Ian , Holthaus Blake , Yacoub Simon , Piracha Zain , Zakeri Amanda Sahar , Anderson Cole , Stork Taggart , Joseph Matthew , Nimjee Shahid Mehdi
Published: March 2024

INTRODUCTION:

Acute ischemic stroke (AIS) is the leading cause of long term disability. rtPA treatment of AIS results in intracranial hemorrhage (ICH) in 7% of patients with 40% mortality. Increased matrix metalloprotease-9 (MMP-9) correlates with ICH, while reduced levels maintain integrity of the blood brain barrier (BBB), preventing ICH. Von Willebrand Factor (VWF) induces both thrombosis and inflammation in large vessel occlusion (LVO) stroke. BB-031 targets VWF, and lyses thrombotic occlusion. BB-025 reverses BB-031.

METHODS:

After 6 hours of autologous canine MCAO, animals were treated with vehicle, BB-031, and BB-031+BB-025. VWF inhibition, TICI scores, and plasma inflammatory markers [VWF, interleukin-1 (IL-1b), interleukin-6 (IL-6), tumor necrosis factor-a (TNF- a), and matrix metalloproteinase-9 (MMP-9)] were analyzed over the course of the study.

RESULTS:

Within 15 minutes of vehicle treatment, VWF increased by 3.102 ± .382 ng/ml (n = 6) whereas BB-031 reduced VWF by 0.223 ± .154 ng/ml (p < 0.05) (n = 8). BB-031-treated animals had TICI > 2B in 62.5% of the animals. Although IL-1b and IL-6 were unchanged, and TNF-a was not detectable, MMP-9 levels were lower in BB-031-treated animals at sacrifice compared to both vehicle and BB-031+BB-025 (p < 0.0001).

CONCLUSIONS:

BB-031 treatment inhibited VWF, increased reperfusion, and reduced MMP-9 after canine MCAO, suggesting that in addition to recanalization, inhibiting VWF mitigates inflammation and iatrogenic ICH.
1067 Accuracy of an Augmented Reality Spine Surgery Guidance System With Stereoscopic Targeting Head Mounted Display Compared to Standard Computer Navigation, Robotic Systems, and Existing AR Systems
Authors: O'Connor Tim , Hussain Ibrahim , Srivastav Sudesh , Pan John , Voegeli Thomas
Published: March 2024

INTRODUCTION:

Augmented Reality (AR) offers the benefit of improved hand-eye coordination by accurately superimposing 3D stereoscopic displays for surgical instruments onto anatomic landmarks.

METHODS:

120 pedicle screws were implanted using an AR system (OnPoint AR, OnPoint Surgical, Bedford, MA) (thoracic 50, lumbosacral 70; pre-op CT 40, O-arm 80). Heary grading was applied by an independent radiologist assessing the degree of pedicle breaches. 3D measurements of positional error (PE) and angular error (AE) were performed by comparing post-operative CT scans of implanted screws with planned trajectories. Statistical analyses compared PE and AE for OnPoint AR with the available values for other systems using an unequal variance t-test method.

RESULTS:

113 screws placed demonstrated Heary grade 1 accuracy. 6 screws had a larger diameter than the pedicle and were planned with in-out-in technique with Heary grade 2 accuracy. One screw demonstrated a lateral breach (grade 2) caused by a loose connection to the screwdriver. PE and AE (mean ± 1SD) for OnPoint AR were the following: for intra-operative spin 1.1mm±0.5mm and 1.3°±0.5°; for pre-operative CT 1.9mm±1.2mm and 2.2°±1.3°. Percent increment in PE and AE for Medtronic Stealth Station, Brainlab navigation, Stryker nav3i, Medtronic Mazor X robot, Globus Excelsius robot, Augmedics Xvision, and Novarad VisAR compared to OnPoint AR ranged between 40–80%, with differences being highly significant for all comparisons.

CONCLUSIONS:

PE and AE for placing pedicle screws are statistically significantly smaller for the novel AR system compared to existing navigation, robotic, and AR systems. A positional error of 1.1mm and angular error of 1.3° makes this technology particularly suited for small pedicles, challenging anatomy, and MIS techniques.
1069 Assessing the Safety and Efficacy of Spinal Anesthesia in Patients With Higher Risk Comorbidities
Authors: Karimi Helen , Ahsan Tameem , Yu-Der Wang Andy , Kanter Matthew , Olmos Michelle , Kosarchuk Jacob , Balonov Konstantin , Liu Penny , Riesenburger Ron I. , Kryzanski James
Published: March 2024

INTRODUCTION:

Spinal anesthesia (SA) is a safe and effective alternative to general anesthesia (GA) for lumbar surgery. Widespread adoption of SA has not occurred presumably due to surgeons’ concerns for difficulties in management of patients with comorbidities. Obesity (BMI =30 kg/m2), anxiety, obstructive sleep apnea, re-operation at the same level, and multilevel operations have recently been identified as risk factors for perioperative complications.

METHODS:

A retrospective analysis of 422 patients who underwent thoracolumbar surgery under spinal anesthesia by a single surgeon at a single academic center (2017-2021) was carried out. Patient demographics, comorbidities, as well as intraoperative and postoperative complications were abstracted from the medical record. In the overlapping groups, 149 patients had a BMI =30, 95 had diagnosed anxiety, 79 underwent multilevel surgery, 98 had obstructive sleep apnea, and 65 had a prior operation at the same level. The control group included 132 patients without these risk factors. Differences in perioperative outcomes were assessed with the Kruskal-Wallis rank sum test, Pearson's Chi-squared test, or Fisher's exact test using R (The R Foundation, v 4.1.1, Vienna, Austria).

RESULTS:

Postoperative pneumonia was observed in two patients in the anxiety group and in one patient in the reoperative group (p-value < 0.05). There were no other statistically significant differences in intraoperative and postoperative complications within the entire cohort including when stratified by number of comorbidities. Rate of spinal fusion was comparable among groups, though mean length of stay and operative time were different (p-value < 0.001).

CONCLUSIONS:

Spinal anesthesia is a feasible and safe anesthetic modality for most patients, including those with significant comorbidities. An updated algorithm for SA candidate selection is thus recommended.
107 Conventional Catheter-based Angiography Versus Non-invasive Imaging in the Evaluation of Symptomatic Carotid Disease
Authors: Keister Alex , Khalife Jane , Weinberg Joshua H. , Padron Zachary , Vignolles-Jeong; Renato Oliveira Joshua , Shaikh Hamza , Tonetti Daniel , Patel Pratit , Thomas Ajith J. , Nimjee Shahid Mehdi , Jovin Tudor
Published: March 2024

INTRODUCTION:

The indication for invasive treatment of symptomatic carotid disease with CEA or carotid stenting was established based on catheter digitally subtracted imaging (DSA) however operative referral for symptomatic carotid disease is still largely based on non-invasive imaging such as CTA or ultrasound.

METHODS:

Retrospective analysis all consecutive patients who were referred for evaluation and treatment of symptomatic carotid disease after non-invasive imaging with CTA or ultrasound showed ipsilateral carotid stenosis of >50% or occlusion. Patients were included if they had ipsilateral cerebral or ocular ischemia within two weeks of index event.

RESULTS:

A total of 280 patients with stenosis >50 and <100% were included. Of those, 53 (19%) were found to have stenosis <50% leading to treatment with best medical therapy instead of intervention. Out of 50 patients with total occlusion, 16 (32%) were found to have a string sign and were treated with stenting. Percent stenosis of 80 or more on non-invasive imaging was more likely to correlate with stenosis of 50% or more on DSA.

CONCLUSIONS:

In a cohort of two large North American institutions, 19% of patients referred for revascularization of symptomatic carotid disease based on non-invasive imaging were found to have non-significant carotid stenosis and were treated with best medical therapy and 32% of those with suspected occlusion were successfully revascularized. Our findings highlight the importance of catheter cased angiography in the evaluation of carotid disease.
1072 SIJ Fusion Device Testing
Authors: Buck Brian , Wright Nathan , Rajpal Sharad
Published: March 2024

INTRODUCTION:

Screw use for SIJ fixation began in the 1980s with the FDA first classifying SIJ fusion devices in 2002. For 40 years, no standardized test method existed. Various methodologies (for bone screw, intramedullary nail, or spinal fusion implants) were modified to accommodate the design and function of sacroiliac devices including ASTM F543’s torsion, pullout, and insertion tests, ASTM F1264’s three- or four-point bending tests, and ASTM F2193’s cantilever bending tests. For many years, SIJ fusion screw indications were limited to fixation of pelvic bones for sacroiliac joint disruptions and degenerative sacroiliitis. While the FDA typically accepted performance testing according to combinations of the aforementioned tests, the specific test expectations have been relatively undefined with inconsistent testing batteries from submission to submission.

METHODS:

Collaboration among testing experts, manufacturers, and FDA regulators within ASTM’s Spinal Devices sub-committee resulted in the development and publication of ASTM F3574 (Standard Test Methods for Sacroiliac Joint Fusion Devices) based on physiologic loading conditions in the joint as documented in published studies. These tests included: For SI Screws: • Static/dynamic cantilever bending •Static torsion •Driving torque •Pullout For SI Posterior Spacers: •Static/dynamic shear •Static/dynamic torsion.

RESULTS:

The medical device industry now has access to standardized test methods for SI devices while the FDA or other regulators now have device specific test methods to recommend for pre-clinical testing.

CONCLUSIONS:

Many new standards drag through years of development and refinement within sub-committees, but ASTM F3574 developed quickly due to efforts of the Spinal sub-committee task group to meet the needs for SI fusion devices.
108 A Translational Approach to Suppress Local Inflammation in the Ischemic Penumbra and Deliver Local Anti-platelet Activity After Stroke
Authors: Alawieh Ali M. , Grossberg Jonathan Andrew , Tomlinson Stephen
Published: March 2024

INTRODUCTION:

Mechanical thrombectomy is the standard of care for ischemic stroke, but there is a significant mismatch between successful recanalization and clinical outcomes. Inflammation in the ischemic penumbra remains a target for neuroprotective interventions even in recanalized and non-recanalized patients. P-selectin (Psel) is a marker of endothelial cell activation and could be used to deliver therapeutics locally to the site of ischemic injury.

METHODS:

The fusion protein Pselectin-Crry was constructed using single chain antibody sequence linked to the extracellular region of mouse Crry. In-vivo testing using surface plasmon resonance for binding affinity to Psel, and zymosan assay for complement inhibitory activity. In-vivo studies were performed in C57bl/6 mice subjected to transient middle cerebral artery occlusion for 1 hour followed by administration of Psel-Crry 2 hours after reperfusion. Psel-Crry was labelled using far-red fluorescence and live-animal imaging was used to study brain-specific targeting. The modified Neurological Severity (NS) score was used for functional outcome along with survival, infarct volume and histological outcomes.

RESULTS:

Psel-Crry demonstrated dose-dependent complement inhibitory activity, and localized specifically to the stroke brain on in-vivo live imaging. Ex-vivo imaging of explanted brain showed Psel-Crry binding specifically to the injured hemisphere without off-target binding (Stroke vs. Sham, p < 0.001). Psel-Crry resulted in 60% reduction in infarct volume at 3 days compare to vehicle (N = 8/group, p < 0.05), reduction in NS scores compared to vehicle (Median 3 vs. 1.5, p < 0.05), and improved 1-week survival (80% vs. 50%, p < 0.05). Histological analyses demonstrated preservation of dendritic arborization in the ischemic penumbra with Psel-Crry treatment with concurrent significant reduction in microglial activation.

CONCLUSIONS:

Psel-Crry is a translational agent that can achieve local complement inhibitory effect and antiplatelet activity after stroke and has promise for potential use as ajuvant therapy in stroke.
109 Exploring an Angiogenic Biomaterial Strategy for the Treatment of Moyamoya Disease
Authors: Chaparro Eduardo , Erning Kevin , Fulton Amy , Mace Brian , Gonzalez L. Fernando , Hasan David M. , Segura Tatiana
Published: March 2024

INTRODUCTION:

Moyamoya disease is a rare cerebrovascular disorder characterized by progressive intracranial artery narrowing followed by a net of smaller fibrous root like blood vessels created in response to the scarcity of oxygen. Current treatment options for moyamoya disease are limited and often involve invasive surgical procedures. Recent studies have shown that hyaluronic acid (HA) gels can enhance angiogenesis and improve blood flow in ischemic tissues. Our laboratory has demonstrated that delivering angiogenic biomaterials in previously damaged brain tissue can generate a vascularized bed laying the groundwork for the use of angiogenic materials to other ischemic conditions.

METHODS:

We used C57/B6 mice, male and females, divided into 4 groups: 1. Controls – no surgery, no treatment; 2. Vehicle – unilateral occlusion of the internal carotid artery (ICA) and contralateral stenosis of the ICA, 2mm craniotomy, treated with saline solution; 3. Surgery as previously described, treated with a HA gel 4. Surgery as before, treated with Cluvena. Brains were dissected 2 weeks after treatment, sectioned and stained with CD31 to label new endothelial cells.

RESULTS:

Area fraction was used to calculate CD31 fluorescence. We found that animals subjected to occlusion/stenosis with no treatment had a statistically significant lower vessel percent area in comparison with normal animals. In contrast, animals treated with HA or Cluvena had a statistically significant higher vessel percent area than untreated animals.

CONCLUSIONS:

The use of biomaterials showed to be effective restoring vascularity in brains subjected to ischemia. There is a positive trend in favor of Cluvena versus HA restoring endothelial cells, suggesting that biomaterials including HA could provide enough angiogenic effect. Further research is needed to confirm the benefits of Cluvena.
110 Trends and Risk Factors for Medical Malpractice Litigation in Open Cranial Neurosurgery
Authors: Gupta Saksham , Stenberg Carl , Gerstl Jakob V. E. , Nonnenbroich Leo , Lindberg Rebecca , Chabros Jeremy , Smith Timothy R. , Arnaout Omar
Published: March 2024

INTRODUCTION:

Neurosurgery is the most litigious specialty amongst all specialties across medicine. Understanding the reasons for malpractice claims can help inform neurosurgeons improve care and mitigate litigation risk.

METHODS:

The Westlaw Edge and LexisNexis databases were searched for cases involving medical malpractice claims due to cranial surgery between the years 1985-2023. Data collected included case date, verdict ruling, jurisdiction, sustained injuries, and awards or settlement amounts.

RESULTS:

Of 1546 cases reviewed, 317 were identified as malpractice claims resulting from cranial surgery. The primary causes for litigation were perioperative complications (n=115), delayed or denied treatment (n = 95), insufficient follow-up care (n = 51), inappropriate procedure selection (n = 39), and inadequate informed consent (n = 8). Tumor surgery had the highest number of claims (n = 81), followed by vascular (n = 59), trauma (n = 54), infection (n = 43), functional/epilepsy (n = 28), and other/not defined (n = 56). Regarding verdict ruling, 39.4% (n = 125) ruled in favour of the defendant; 20.5% (n = 65) in favour of the plaintiff; 2.2% of verdicts resulted in mixed ruling (n = 7); in 10.7% (n = 34) of claims were resolved in an out-of-court settlement; and in 27.1% (n = 86) the verdict was not available. The subspecialty with the highest proportion of plaintiff verdicts was tumor 29.2%, (n = 19), and tumor also had the highest proportion of defendant verdicts 26.40%, (n = 33). The average verdict amount awarded to plaintiffs was $5,592,703, while the average settlement amount was $2,751,807.

CONCLUSIONS:

The authors highlight several risk factors for medical malpractice claims across cranial neurosurgery. These results suggest that litigation may be mitigated with accurate and timely diagnosis, timely referrals and coordinated care.
1132 Phase 1 Correlates of Seizure Onset Zone for Prediction of sEEG Placement and Clinical Outcomes
Authors: Katlowitz Kalman , Allam Anthony , Weiner Howard L. , Curry Daniel
Published: March 2024

INTRODUCTION:

Approximately 20 million people worldwide suffer from drug resistant epilepsy. Treatment of the seizure onset zone (SOZ) can reduce seizure burden. When phase 1 testing fails to identify a clear surgical lesion, stereo-electroencephalography (sEEG) offers a high-resolution spatial map of cortical and subcortical activity. However, each additional lead placed also increases the chances of a complication. Preoperative identification of optimal targets is crucial to minimizing the risk-benefit ratio of sEEG placement.

METHODS:

We studied epilepsy patients that underwent sEEG placement followed by resection, stimulation, or laser ablation at a single institution from 1/2012 to 11/2021. Leads were identified by their respective Phase 1 indications. Preoperative and 1-year postoperative clinical outcomes were compared. Hypothesis testing was performed via the Wilcoxon rank sum test and Fisher’s exact test. A logistic generalized linear mixed effect model was used for multivariate analysis.

RESULTS:

101 patients had 1752 leads placed with 239 SOZs found and treated. Mean weekly seizure frequency decreased from 25.2 to 7.8 (p < 0.001). SOZ leads were more likely to have concordant findings (p < 0.001) across studies. Lesions with PET hypometabolism (OR 1.4), MRI abnormalities (OR 1.9), MEG Clusters (OR 1.9) and calcifications (OR 3.2) were significantly more likely to predict SOZ, though PET hypometabolism was not significant in multivariate analysis. While the reason for lead placement in the SOZ did not predict seizure outcomes, patients with other lesions that had MEG Clusters or Calcifications had an average 15% worse seizure reduction than those without (p < 0.005).

CONCLUSIONS:

Certain Phase 1 aspects of a putative lesion, such as MRI abnormalities, the presence of calcifications, or MEG clusters can predict SOZ and clinical outcomes.
1134 A Call to Revise the Thirty-year-old SRS Dose Guidelines for Brain Metastases
Authors: Niranjan Ajay , Wei Zhishuo , Lunsford L. Dade
Published: March 2024

INTRODUCTION:

Stereotactic Radiosurgery (SRS) currently is the most widely used neurosurgical strategy for treatment of brain metastases. Many centers still rely on 30-year-old dose volume guidelines derived from RTOG 90-05.

METHODS:

Between 2014 and 2020 330 NSCLC patients (median age = 65 years) with 2910 brain metastases underwent Gamma knife SRS. The number of tumors treated per patient ranged from 1-56 and the total tumor cumulative volume ranged from .05 to 33.09 cc (median = 3.17). The median prescribed tumor margin dose was 18 Gy.

RESULTS:

Median overall survival after radiosurgery was 15.5 months. Radiological tumor progression was noted 66 out of 2910 tumors (2.27%) in 51 out of 330 patients (15.45%). Tumors were divided into 4 categories based on tumor volumes (<1.5 cc, 1.5-<5 cc, 5-<10 cc, and = 10cc). The effect of margin dose, and % tumor covered in 18 Gy, 20 Gy, and 24 Gy on local tumor control was analyzed for all 4 categories. In tumors with volumes >1.5 cc local tumor control was significantly better (P < 0.05) when =65% of the tumor volume received at least 24 Gy. No relationship was found between tumor control and 75, 90, and 100 % volumes receiving 18 or 20 Gy.

CONCLUSIONS:

In this study neither conformality of dose delivery nor tumor margin doses were the most important predictors of local tumor control as long as =65% of the tumor volume received at least 24 Gy. This finding can serve as a prescriptive guideline that allows margin doses below the RTOG guidelines, reduces reliance on strict conformality, and improves tumor control.
1135 Classification of Temporal Lobe Epilepsy Anatomo-clinico-electrical Hypotheses: A Stereo EEG Study
Authors: Mallela Arka , Hect Jasmine , Pupi Michael , Anthony Austin , Fogg David , Angonese Arthur , Abou-Al-Shaar Hussam , Roberts Zachary , Anand Sharath Kumar , Aung Thandar , Gonzalez-Martinez Jorge
Published: March 2024

INTRODUCTION:

Temporal lobe epilepsy (TLE) has historically been divided into mesial and lateral (neocortical) TLE, but electrophysiological, semiological, and anatomical evidence indicate that the epileptogenic zone (EZ) and areas of propagation involve both temporal and extratemporal structures. Hypothesis-driven, structured interrogation is crucial for a successful stereo EEG (SEEG) exploration and subsequent successful surgical intervention.

METHODS:

59 patients (ages 19-77) with drug-resistant TLE underwent SEEG at our institution from 2020-2022. We retrospectively reviewed each patient’s multidisciplinary discussions, history, imaging, and outcomes. We proposed four types of implantation hypotheses: temporal, temporal/basal/occipital, anterior perisylvian, and perisylvian. We quantitatively validated these types against anatomic coverage and semiology using unsupervised clustering and clinically by comparing classification to rates of successful localization of the epileptogenic zone (EZ) and seizure outcomes.

RESULTS:

Temporal (only) hypotheses were the least frequent (13.6%), followed by temporal/basal/occipital (25.4%), anterior perisylvian (30.5%), and perisylvian (30.5%). The hypotheses were not different in age at SEEG (p = 0.32), sex (p = 0.67), and handedness (p = 0.33). Frequent semiological features by type were: temporal – autonomic features, dÉjÀ vu; temporal/basal/occipital – visual and language disturbance; anterior perisylvian – oromotor; perisylvian – sensory manifestation. Clustering was validated against semiology (RI = 0.63) and lobar coverage (RI = 0.73). Successful localization of the EZ occurred in 79.7% and did not associate with hypothesis type (p = 0.22). Hypothesis type (p = 0.30) or EZ localization (p = 1.00) did not associate with the presence of an MRI lesion. 6-month Engel 1a rate was 71% and did not vary by hypothesis type (p = 0.29).

CONCLUSIONS:

The anatomo-clinico-electrical hypotheses in TLE must consider both temporal and extratemporal structures and not be limited by a medial vs. lateral TLE mindset. This proposed classification of TLE hypotheses can serve as starting point for multidisciplinary patient discussion as well as a tool to compare SEEG exploration and outcomes across centers.
1137 Prospective, Multicenter, International Registry of Deep Brain Stimulation for Dystonia: A Sub-analysis of Cervical Dystonia Patients
Authors: Albanese Alberto , Chen Lilly , Jain Roshini , Krauss Joachim K.
Published: March 2024

INTRODUCTION:

Management of dystonia using Deep Brain Stimulation (DBS) is a well-established therapeutic approach. However, optimal DBS target sites in patients with cervical (focal) versus generalized dystonia are thought to diverge and be specific for particular connections (Horn 2022). DBS devices equipped with capabilities such as directionality and Multiple Independent Current Control (MICC) may offer potential for improved clinical outcomes.

METHODS:

This is a sub-analysis of patients with focal (cervical) dystonia only or cervical dystonia in the context of segmental or generalized dystonia assessed as part of a prospective, multicenter, international dystonia registry (NCT02686125). All patients receive an MICC-based, directional DBS system (Vercise, Boston Scientific). Patients are followed up to 3-years (post-implant). Several study assessments are being collected to evaluate their dystonia symptoms (e.g., TWSTRS), quality of life, and overall satisfaction. Adverse Events are also collected.

RESULTS:

A total of 43-patients (mean age 56.9-years, 58% females) with focal (cervical) dystonia only and 83 patients (mean 41.95-years, 61% females) with cervical dystonia in context of segmental or generalized dystonia have been evaluated. Both groups reported significant improvement in overall TWSTRS scores – however the extent varied. In the cervical-only cohort, a 19.9-point improvement was noted at 6-months (n = 25) and sustained up to 1-year (23.2-point improvement, n = 20). In those with cervical dystonia within frame of segmental or generalized dystonia, a 9.7-point and 7.3-point improvement in overall TWSTRS scores was noted at 6- (n = 50) and 12-months (n = 38), respectively. Updated data will be reported.

CONCLUSIONS:

This registry represents the first comprehensive, large-scale collection of real-world outcomes associated with dystonia patients implanted with a directional DBS system capable of MICC. Preliminary results demonstrate significant improvement in patients with cervical dystonia (alone or in context of segmental or generalized dystonia) following DBS.
118 Intraoperative Radiotherapy Combined With Spinal Stabilization Surgery. A Novel Treatment Strategy for Spinal Metastases. First Experiences at a Single Center
Authors: Krauss Philipp , Bonk Maximilian-Niklas , Stemmer Bastian , Wolfert Christina , Sommer Björn , Stüben Georg , Kahl Klaus-Henning , Shiban Ehab
Published: March 2024

INTRODUCTION:

Contemporary treatment of spinal metastases (SM) aims on preserving spinal stability, neurological status, local control and functional status. It consists of spinal surgery followed by radio- and chemotherapy. Adjuvant therapy is performed after several weeks to prevent wound healing issues. Intraoperative radiotherapy (ioRT) is a solution to shorten treatment time, successfully applied in brain tumor, breast and colorectal surgery but not SM to date.

METHODS:

Results on morbidity and mortality of ioRT combined with stabilization surgery in SM in a first single center series are described. Stabilization is performed as CT-navigated open or percutaneous procedure using a carbon screw-rod system followed by 50kV photon-ioRT using the ZEISS Intrabeam during a single session in prone position. The ioRT probe is placed through a guide canula via navigation and positioning is controlled by ioCT to enable RT isodose planning in the OR. Patient characteristics, perioperative specifications and postoperative follow up along with adverse events (AE) are reported.

RESULTS:

11 (7 female) patients (69 ± 9.4y) received treatment from 07/22-04/23. Median SINS was 8 [7-10] IQR, with metastasis located in thoracic (n = 9) and lumbar (n = 2) spine. 6 patients receive open, 4 percutaneous stabilization and 1 decompression only. Mean length of surgery was 153±52 min. with 2 Patients receiving 4 and 8 patients receiving 8 screws respectively. In 2 Patients radiotherapy was not completed due to bending of the guide canula with consecutive security abortion of ioRT. All other patients received 8Gy isodoses during 2-6 min. Patients treated had ESCC 1a-2. Mean follow up was 63 ± 49 days. 4 patients experienced AEs including 1 case of fatal surgical site infection.

CONCLUSIONS:

50 kV photon ioRT for SM can be a promising technique for selected cases of SM.
119 A Hook Effect-based Lateral Flow Immunoassay Sensor for Cerebrospinal Leak Detection
Authors: Sonstein William , Oh Hyun-Kyung , Park Jinhee , Maher Simon , Navarro Mario , Vargas Angel , Kim Min-Gon
Published: March 2024

INTRODUCTION:

A rapid test for the presence of cerebrospinal fluid (CSF) would be ideal in the management of postoperative fluid collections after spinal surgery. In order to ascertain the nature of the fluid the gold standard has been to send the fluid for gel electrophoresis which is time consuming and expensive in order to determine the presence or absence of beta-2 transferrin.

METHODS:

A cassette containing a lateral flow strip was used with two conjugates: a gold nanoshell-anti-TF antibody conjugate (conjugate 1) and a gold nanoshell-lectin conjugate (conjugate 2).After a sample is applied, a chromatographic sandwhich forms in two detection zones to yield a detectable dark line: Test line 1 (T1) where anti-TF antibodies are embedded form a sandwich reaction with analyte (TF) and with conjugate 1 and test line 2 (T2) where embedded serum glycoproteins react with conjugate 2. A control line with anti-mouse IgG antibody is embedded to form a reaction with conjugate 1. We availed the well-known hook effect as both T1 and T2 detection zone development was inhibited by the saturation of binding sites of the conjugates and embedded material.

RESULTS:

18 clinical samples of either CSF or postoperative drain fluid (serum) were tested using a third generation LFI. There were 7 CSF samples and 11 serum samples and one with buffer only. The hook effect-based LFI successfully discriminated positive clinical CSF samples from negative samples in all cases.

CONCLUSIONS:

This novel hook effect-based LFI sensor offers a fast, highly accurate and easy to use POC test for CSF leak.