bluuebunny/crossref_metadata_2025_split huggingface dataset:
387 Adaptive Priming Meets Innate Killing: TCR-Activated CD8+ T Cells Can Kill Tumor Cells in an MHC-Independent Manner via NKG2D
Authors: Fecci Peter Edward , Lerner Emily 
Published: March 2024

INTRODUCTION:
The accepted paradigm for antitumor immunity relies upon tumor cell kill by CD8+ T cells recognizing cognate antigens presented in the context of target cell major histocompatibility complex class I (MHC-I) molecules.

METHODS:
We sought to better evaluate the role of MHC-I expression within the tumor microenvironment.

RESULTS:
T cell-activating immunotherapies, surprisingly, remained effective against glioma and melanoma lines engineered to lack MHC-I expression. Such efficacy proved independent of NK cells and, instead, relies consistently upon CD8+ T cell-mediated cytotoxicity, despite the absence of MHC-I on tumor targets. This cytotoxicity is both antigen- and MHC-agnostic and, instead, is mediated by T cell NKG2D engagement of NKG2D ligands on tumor cells, which are upregulated on MHC-loss variants. Necessarily, tumor cell kill in these instances is antigen-independent, although prior T cell receptor activation is required and can be furnished by myeloid cells or even neighboring MHC-replete tumors cells. In this manner, adaptive priming can beget innate killing. These mechanisms are active in vivo in mice, as well as in vitro in human tumor systems, and are obviated by NKG2D knockout or blockade. Tumor cell killing following T cell NKG2D engagement is Fas-independent and appears to involve granzyme.

CONCLUSIONS:
Such findings challenge the traditional model of T cell-mediated tumor immunity and likewise identify the NKG2D/NKG2DL axis as a novel therapeutic target for enhancing T cell killing of MHC loss variants.
393 Cerebral Oximetry Using the USIC Protocol Is a Reliable Tool for Indicating Selective Intraluminal Shunting During Carotid Endarterectomy
Authors: Hejcl Ales , Jiránková Katerina , Hrach Karel , Sames Martin 
Published: March 2024

INTRODUCTION:
Indication to selective shunting during carotid endarterectomy (CEA) is based on monitoring during the procedure. Cerebral oximetry (CO) using near-infrared spectroscopy (NIRS) is one of the monitoring tools but no clear cut off value for an intraluminal shunt insertion has been established.

METHODS:
125 patients underwent CEA under LA and were monitored clinically through the whole procedure. The patients also underwent bilateral NIRS monitoring during the surgery. During the monitoring period, we first clamped the external carotid artery (ECA), and after a 1 minute delay followed by clipping the internal carotid artery (ICA). The decrease in the cerebral oximetry values was analyzed separately after selective ICA clipping (ÚstÍ Selective Internal carotid artery Clamping “USIC” protocol). The decision to use a shunt was based solely on clinical symptomatology but the NIRS data were recorded and analyzed. All patients underwent DWI before and after CEA.

RESULTS:
One hundred and six patients (85%) underwent CEA without clinical deterioration while 19 patients (15%) clinically deteriorated during surgery. The mean drop in the cerebral oximetry after selective ICA clamping in clinically stable patients was 6% while in patients with clinical deterioration the NIRS decreased by 15% (p < 0.05). When we set the cut-off value for selective shunting as a 10% decrease of the ipsilateral cerebral oximetry after selective ICA clamping, the sensitivity of the technique was 100% and the specificity 83%.

CONCLUSIONS:
Our study showed that a 10% decrease in the ipsilateral brain tissue oximetry after selective cross-clamping the ICA provides a reliable cut-off for selective shunting during CEA. More, bilateral NIRS monitoring allows differentiation between systemic or local events leading to brain hypoxia.
401 Applying Machine Learning for Risk Stratification and Acute Clinical Outcome Prediction Amongst Aneurysmal Subarachnoid Hemorrhage Patients
Authors: Buchlak Quinlan , Leveque Jean-Christophe A. , Krause Katie L. , Farrokhi Farrokh 
Published: March 2024

INTRODUCTION:
Subarachnoid hemorrhage (SAH) is a common stroke subtype and is often caused by aneurysmal rupture. Accurately predicting aneurysmal SAH (aSAH) clinical outcomes may facilitate timely and effective treatment.

METHODS:
A dataset encompassing 12,070 aSAH Australian patients was analysed using multivariate logistic regression and machine learning techniques. Models were designed to predict the need for a surgical procedure, intensive care unit (ICU) admission, the need for continuous ventilation, prolonged length of stay (LOS), mortality, and discharge status.

RESULTS:
Surgical intervention was positively associated with younger age and female gender and negatively associated with indigenous Australian status. ICU admission was positively associated with age, female gender, surgery and indigenous status. The need for continuous ventilation was associated with age and ICU admission and negatively associated with female gender and surgery. Prolonged LOS was associated with older age, undergoing surgery and requiring ICU admission. Mortality was negatively associated with younger age, female gender and receiving surgical treatment. The Monash SAH Scores were developed, consisting of four scales that may be used to efficiently facilitate risk stratification and decision making in clinical practice. Machine learning models were capable of accurately predicting mortality with strong performance.

CONCLUSIONS:
This nation-wide study identified risk factors associated with acute clinical outcomes amongst aSAH patients. A simple scoring system was developed that may be readily applied to clinical practice to facilitate aSAH patient risk stratification and treatment planning.
403 Malignant Cerebral Venous Infarction: Decompressive Craniectomy Versus Medical Treatment
Authors: Ahmadi Sina , Baharvahdat Humain , Ganjeifar Babak , Etemadrezaie Hamid , Zabihyan Samira , Mowla Ashkan 
Published: March 2024

INTRODUCTION:
Cerebral venous thrombosis (CVT) is a common stroke in young adults and is associated with 8% mortality. High intracranial pressure (ICP) and brain herniation are these patients' most common causes of death.

METHODS:
In this retrospective study, Patients with the following inclusion criteria have entered the study: 1) CVT proven by contrast-enhanced magnetic resonance venogram and/or computed tomography venogram, 2) malignant CVT (impending brain herniation according to imaging and clinical finding), and 3) age between 16 and 80 years. Patients with deep venous system thrombosis, Glasgow Coma Scale (GCS) score of 3, and bilateral nonreactive mid-position pupils or mydriasis on admission were excluded. Patients were classified into 2 groups: surgical group (DC group) including patients who received medical treatment and DC and medical group (MG) including patients who received only medical treatment. Outcomes and complications were assessed and compared between the 2 groups.

RESULTS:
Of 357 patients with CVT hospitalized in our center, 48 patients entered the study. 23 patients were managed medically, and 25 patients were managed surgically. There was no significant difference between the groups concerning age, sex, presenting symptoms, transient and permanent risk factors of CVT, GCS score on admission, and pupils’ reactivity on admission. All patients in the MG died during hospitalization in comparison with 8 patients in the DC group (100% vs. 32%, P < 0.001). A favorable outcome (modified Rankin scale score 0e2) was achieved in 52% of the DC group and 0% of the MG group (P < 0.001).

CONCLUSIONS:
Our study confirmed that in contrast with DC, medical treatment could not prevent transtentorial herniation. DC is not only lifesaving for patients with CVT with impending brain herniation but also results in favorable outcomes in most patients.
407 Results of Biphasic Calcium Phosphate Bone Graft With Submicron-Sized Needle-Shaped Surface Topography as Standalone Alternative to Autograft Are Favorable in a Prospective, Multi-center, Randomized, Intra-patient Controlled Trial
Authors: Fanous Andrew , Butrico Casey , Delawi Diyar , Hoebink Eric , Kempen Diederik , Van Susante Job , Kruyt Moyo 
Published: March 2024

INTRODUCTION:
Pseudoarthrosis after spinal fusion is an important complication leading to revision spine surgeries. Iliac Crest Bone Graft is considered the gold standard, but with limited availability and associated co-morbidities, spine surgeons often utilize alternative bone grafts.

METHODS:
Adult patients indicated for instrumented PLF of one to six levels from T10-S2 were enrolled at five participating centers. After preparation of the bone bed, one side was grafted with 10 cc of autograft per level containing a minimum of 50% iliac crest bone. The other side was grafted with 10 cc of BCP < µm granules standalone. In total, 71 levels were treated. Prospective follow-up included a fine-cut (<1 mm) Computerized Tomography (CT) at one year. Fusion was systematically scored as fused or not fused per level per side by two spine surgeons blinded for the procedure.

RESULTS:
The first fifty patients enrolled are included in this analysis. Average age was 57 years old, with 60% female and 40% male. The diagnoses included deformity (56%), structural instability (28%), and instability from decompression (20%). The fusion rate determined by fine-cut CT for BCP < μm was 76.1% (54/71 levels), which compared favorably to the autograft fusion rate of 43.7% (31/71 levels). Fusion of the BCP < μm side was not contingent upon fusion of the autograft side, as 36.6% (26/71) of levels fused on the BCP < μm side but did not fuse on the autograft side. Binomial modeling revealed that the odds of fusion of BCP < μm was 2.54 times higher than that of autograft.

CONCLUSIONS:
These data, aiming to determine non-inferiority of standalone BCP < μm as compared to autograft for PLF, are promising. Ongoing studies with additional patients are forthcoming.
409 Evaluation of a Novel Vancomycin-Infused, Biomimetic Bone Graft in a Rat model of Spinal Implant-Associated Infection
Authors: Rajkovic Christian , Tracz Jovanna , DeMordaunt Trevor , Davidar Daniel , Perdomo-Pantoja Alexander , Judy Brendan F. , Cottrill Ethan , Hernandez Vaughn , Lin Jessica , Lazzari Julianna , Dikeman Dustin , Archer Nathan , Witham Timothy F. 
Published: March 2024

INTRODUCTION:
Postoperative infection is a complication of spinal fusion surgery resulting in increased patient morbidity. Strategies including intraoperative application of powdered vancomycin have been proposed to reduce the incidence of infection, however such antimicrobial effects are short-lived.

METHODS:
Instrumentation of the L4-L5 vertebrae was performed mimicking pedicle screw and rod fixation in 30 rats. Titanium inoculated with PBS or 1x105 CFU bioluminescent MRSA and biomimetic bone grafts infused with varying concentrations of vancomycin were inserted before closure. Infection was quantified during the six-week postoperative period using IVIS bioluminescent imaging. Arthrodesis was evaluated using micro-CT. Histological analysis was utilized to evaluate fusion and leukocyte infiltration.

RESULTS:
Infected animals receiving a bone graft infused with high-dose vancomycin (0.89 mg/g) exhibited significantly lower bioluminescent signal over the six-week postoperative infection period (p = 0.032) than control animals inoculated with MRSA and implanted with bone grafts lacking vancomycin. Both high and low-dose (0.18 mg/g) vancomycin-infused grafts resulted in a statistically significant reduction in average bioluminescence when compared to control animals (p = 0.018 and p = 0.027, respectively), independent of time. MicroCT analysis of animals from each group revealed pseudoarthrosis only in the control group, suggesting a correlation between infection and pseudoarthrosis. Histology revealed the formation of fusion masses in all animals receiving vancomycin infused-bone grafts regardless of MRSA inoculation, with clearance of infection indicated by lack of abscess formation. MRSA-inoculated control animals receiving no vancomycin within the bone graft demonstrated significant abscess formation and lack of fusion mass.

CONCLUSIONS:
The novel vancomycin-infused, biomimetic bone graft effectively mitigated implant-associated infection while promoting fusion in a rat model of instrumented lumbar fusion.
412 Incisional Negative Pressure Wound Therapy Following Posterior Instrumented Spinal Fusion: A Single Surgeon’s Experience and Cost-Benefit Analysis
Authors: Kramer Dallas E. , Bharthi Rosh , Myers Daniel , Chang Patrick , Dabecco Rocco M. , Xu Chen , Kwong-Tak Yu Alexander 
Published: March 2024

INTRODUCTION:
Surgical site infections (SSIs) following spine surgery are associated with significant morbidity and resource utilization.

METHODS:
We retrospectively reviewed all patients who received posterior instrumented spinal fusion by the senior author between July 2017 and December 2019 at a Level I trauma center. Statistical analysis was performed using Chi-square and Student’s t-tests.

RESULTS:
A total of 85 patients with standard surgical dressings and 144 patients with iNPWT were included for analysis. Patients in the iNPWT group were significantly older (61.8 vs. 58.5 years, p = 0.042) and more likely to be diabetic (36.8% vs. 23.5%, p = 0.037). Surgeries in the iNPWT group were associated with significantly greater blood loss (1298 mL vs. 998 mL, p = 0.036) and involved more instrumented levels (6.6 vs. 4.9, p < 0.0001). Prophylactic iNPWT use was associated with significantly lower rates of wound dehiscence (21.5% vs. 34.1%, p = 0.036) and SSI requiring operative treatment (8.3% vs. 21.2%, p = 0.005). The incidence of wound dehiscence requiring operative wound revision was lower with iNPWT (14.6% vs. 24.7%, p = 0.056), though it did not reach statistical significance. Number needed to treat (NNT) with iNPWT to prevent one SSI was 7.79. The cost of preventing one operative SSI was $5,096. Cost-benefit analysis demonstrated a potential mean savings of $26,149 per operative SSI and $326,862 per 100 patients undergoing posterior instrumented spinal fusion with iNPWT.

CONCLUSIONS:
Prophylactic iNPWT use significantly reduced rates of wound dehiscence, SSI requiring operative treatment, and affords a potential SSI-related cost savings of $326,862 per 100 patients treated.
420 Decrease in Post-Coiling Aneurysm Recanalization With Regular Aspirin Use
Authors: Spellicy Samantha , Kraljic Steven , Abdelgadir Jihad , Zomorodi Ali R. , Torner James , Hasan David M. 
Published: March 2024

INTRODUCTION:
Endovascular coiling has remained an efficacious mechanism for aneurysm treatment. While continued biomechanical advancements in coil design have led to improved aneurysm embolization rates (1), aneurysm recanalization is estimated to remain between 21-33% (2, 3, 4). Post-occlusion, cerebral aneurysm sac growth has been identified as one of the driving components of aneurysm recurrence (2, 5). Recently, antiplatelet agents such as aspirin (ASA) have been shown to be significantly associated with decreased aneurysm growth and rupture (6, 7, 8).

METHODS:
All aneurysms treated by a single surgeon over 10 years (n = 2236) were screened for adherence to inclusion criteria. The primary endpoint was follow-up more than 12 months from the original intervention. Of 525 treated with coils only, 109 patients reported regular ASA use (defined as = 3x/ week, irrespective of dose). No significant demographic differences were identified between patients with regular ASA use and those without. While there were no significant differences in aneurysm size, location, or history of rupture, there was an increased presence of daughter sacs in patients without regular ASA. Rates of aneurysm recanalization, defined as a change of Raymond-Roy occlusion classification =1, were compared between ASA-treated and non-ASA-treated groups.

RESULTS:
Of the 109 coiled aneurysms with concomitant regular ASA use, only 9.2% underwent recanalization compared to 23.6% in patients without regular ASA use (P = 0.001, OR = 0.33, 95% CI = 0.15–0.66). Furthermore, when specifically considering cases of recanalization that only demonstrated sac growth, 5.5% occurred with regular ASA use compared to 18% without (P = 0.001, OR = 0.26, 95% CI = 0.09–0.63).

CONCLUSIONS:
ASA use significantly decreased the odds of post-coiling aneurysm sac growth and recanalization 12 months post-original intervention when compared to those without regular ASA use.
425 Getting Everyone Up to Speed: A Single Institution Pilot of a Neurosurgery Sub-internship Bootcamp
Authors: Suarez Alexander , Jackson Joshua , Raghavan Alankrita , Venkatraman Vishal , Cook Steven , McDaniel Kate , Goodwin C. Rory 
Published: March 2024

INTRODUCTION:
At many institutions, first and second year medical students gain exposure to neurosurgery primarily through shadowing and research projects. Opportunities to acquire clinical experience and technical skills before a neurosurgery sub-internship are often limited. Consequently, students starting sub-internships have wide variability of clinical knowledge and experience.

METHODS:
We implemented a one-day boot camp at our university. The morning session followed a didactic format covering 14 topics. The afternoon session utilized hands-on stations: navigation-based EVD simulation, burr hole drilling, pinning, spine laminectomy/instrumentation, and OR orientation. Participants completed a pre-test and post-test survey using a 9-point Likert scale (Strongly Disagree [1] to Strongly Agree [9]).

RESULTS:
Ten medical students participated in the pilot. All participants rated the boot camp positively (Average score of 9.9 ± 0.2 out of 10). Students identified key areas they felt least comfortable with via the pre-test: functional neurosurgery (2.6 ± 1.4), management of neurosurgical floor patients (3.0 ± 1.6), and examination of comatose patients (4.1 ± 2.3). At the end of the event, students expressed statistically significant increased comfort across 16 of the 17 metrics; maximal improvement was noted in brain tumor imaging interpretation (5.9 ± 1.1 vs. 2.9 ± 1.9, p < .001) and knowing what is expected of a sub-intern (7.0 ± 1.1 vs. 4.0 ± 1.6, p < .001).

CONCLUSIONS:
We successfully implemented a one-day boot camp for medical students about to start their sub-internships. Moving forward, we plan to expand the hands-on learning to other medical students in the region and provide the didactic sessions virtually to allow participation on a national scale. In doing so, we hope to increase sub-internship readiness and reduce barriers for all students interested in neurosurgery.
427 Optimization of Morbidity and Mortality Conference: Results of a Multi-center Pilot at Neurosurgical Training Programs
Authors: Santarelli Justin G. , Sayama Christina M. , Shah Kushal , Benzil Deborah L. 
Published: March 2024

INTRODUCTION:
Neurosurgical morbidity and mortality (M&M) conference is essential to resident education and to quality control. Training programs use different methods for executing the conference, with variability in presentation format, case inclusion criteria, adjudication of findings, and follow-up strategy. Optimal format for this conference is debated.

METHODS:
Ten ACGME-accredited neurosurgical training programs participated in a 3-month pilot to optimize M&M conference. A standardized format was implemented, using a broadly inclusive strategy for case selection, with morbidities selected by residents. Each neurosurgical complication was defined, in group discussion, according to type of error: indication; technique; procedure; judgment; nature of disease. Follow-up intervention was drafted for each case. Surveys were distributed to trainees and attending neurosurgeons before and after the pilot to assess the new format compared to historical standard.

RESULTS:
A total of 302 surveys were returned from attending and resident physicians. Seventy-four % of respondents found the new format to be an improvement (“slightly improved” or “much improved”) and Eight-five % expressed preference for the new standardized format. Fifty-two % of resident respondents believed engagement at the conference was increased. Twenty-six % responded that significant process improvements resulted from the standardized format.

CONCLUSIONS:
This 3-month pilot to optimize neurosurgical M&M conference, undertaken at ten neurosurgery training programs, received favorable reviews by survey. Respondents endorsed high levels of faculty & resident engagement. Case categorization by error was favorably reviewed. Significant process improvements were only noted by a minority of respondents, however, perhaps related to the short duration of the pilot. Overall these results suggest that future amplification of a standardized M&M format across neurosurgical training programs could yield high satisfaction and enhanced resident engagement. Additional attention focused on process improvement will be critical.
428 Artificial Intelligence Training Versus In-person Expert Training in Teaching Simulated Tumor Resection Skills - A Cross-Over Randomized Controlled Trial
Authors: Yilmaz Recai , Fazlollahi Ali , Alsayegh Ahmad , Bakhaidar Mohamad , Del Maestro Rolando 
Published: March 2024

INTRODUCTION:
Neurosurgical simulations equipped with artificial intelligence systems provide an objective quantitative assessment of surgical technical skills and tailored intelligent feedback. These systems allow for repeated practice of complex skills such as subpial brain tumor resection. However, more work is needed to assess the utility of intelligent systems in teaching tumor resection skills, compared to traditional human instruction.

METHODS:
Twenty-five trainees who are currently enrolled in four Canadian medical schools participated in two training sessions, during which they completed a simulated subpial tumor resection five times. Participants were randomly assigned to two feedback groups: (1) real-time intelligent instruction, and (2) in-person human instruction. They were then assigned to the other feedback group in the second (cross-over) session. A composite-score was given by the intelligent system to assess technical skills during each task.

RESULTS:
Trainees who received real-time intelligent instruction significantly improved their composite-score in the first and second training sessions (p = .017, p = .005, respectively). Trainees who received in-person human instruction in the first training session had no statistically significant changes in their composite-score from the first to the last task repetition (p = .119). The composite-score decreased significantly in the second training session with in-person human instruction (p = .004).

CONCLUSIONS:
Real-time intelligent instruction provides an effective way of teaching simulated brain tumor resection skills. Artificial intelligence systems may be a useful addition to current surgical training curricula, providing objective, and tailored assessment and teaching of surgical technical skills in risk-free realistically simulated patient cases. Educators can benefit from these systems to guide their supervision, while trainees can use them for self-guided skill acquisition. Further research may assess the generalizability of these findings to other surgical procedures.