bluuebunny/crossref_metadata_2025 huggingface dataset:
421 GPT-4 Artificial Intelligence Model Outperforms ChatGPT, Medical Students, and Neurosurgery Residents on Neurosurgery Written Board-Like Questions
Authors: Guerra Gage , Hofmann Hayden , Sobhani Sina , Hofmann Grady , Gomez David , Soroudi Daniel , Hopkins Benjamin , Dallas Jonathan , Pangal Dhiraj J. , Cheok Stephanie , Nguyen Vincent , Mack William J. , Zada Gabriel
Published: March 2024

INTRODUCTION:

Artificial intelligence (AI) and machine learning (ML) have transformed healthcare, with applications in various specialized medical fields. Neurosugery can benefit from AI in surgical planning, predicting patient outcomes, and analyzing neuroimaging data. GPT-4, an updated advanced language model by OpenAI with additional training parameters, has exhibited exceptional performance on standardized exams.

METHODS:

GPT-4's performance was examined on 643 Congress of Neurological Suregons (CNS) Self-Assessment Neurosurgery Exam (SANS) board-style questions from various neurosurgery subspecialities. Of those, 477 were text-based and 166 contained images. GPT-4 refused to answer 52 questions that contained no text. The remaining 591 questions were inputted into GPT-4, and its performance was evaluated based on first-time responses. Raw scores were analyzed across subspecialties and questions types, then compared to previous findings on ChatGPT performance against SANS users, medical students, and neurosurgery residents.

RESULTS:

GPT-4 attempted 91.9% of CNS SANS questions and achieved 76.6% accuracy. The model's accuracy increased to 79.0% for text-only questions. GPT-4 outperformed ChatGPT across all neurosurgery categories, scoring highest in Pain/Peripheral Nerve (84%) and lowest in Spine (73%). The model exceeded the performance of medical students (26.3%), neurosurgery residents (61.5%), and the national average of SANS users (69.3%) across all categories.

CONCLUSIONS:

GPT-4 outperformed medical students, neurosurgery residents, and the national average of SANS users. The model's notable accuracy suggests potential applications in educational settings and clinical decision-making, enhancing provider efficicency, and improving patient care.
422 Novel Application of a Mixed-Reality Platform for Learning Neuroanatomy
Authors: Xiao Tianqi , Crofton Andrew , Sathishkumar Buvaneshwari , Enterline Rebecca , Wish-Baratz Susanne
Published: March 2024

INTRODUCTION:

Neuroanatomy is a difficult and intimidating, but also foundational, subject for many medical specialties, especially Neurosurgery. Yet, few modern tools exist for teaching neuroanatomy. This pilot study sought to evaluate the effectiveness of a novel mixed-reality (MR) neuroanatomy visualization software and headset compared to traditional methods of instruction.

METHODS:

This was a prospective randomized cross-over study of volunteer participants in a graduate neuroanatomy course. Students were randomly assigned to either traditional (Group-1) or MR (Group-2) modalities for 2 of 4 course units. All students participated in class lectures. Following each lecture, the MR group conducted MR lab modules while the traditional group conducted traditional cadaveric dissections or yarn and paper lab activities. All students then took the traditional Unit-lab exam. The two groups switched modalities between units. For logistical reasons, the MR laboratory sessions were taught in a separate location than traditional modalities with a teaching assistant. Student opinions were collected via survey and exam results were analyzed via Student’s t-test.

RESULTS:

Thirty-seven students volunteered to participate, with 23 completing the study (Group-1 n = 11 and Group-2 n = 12). Twenty-one students completed the post-course survey. Performance on both lab exams did not differ significantly between traditional and MR groups (p > 0.05). Most participants (95.2%) recommended traditional neuroanatomy teaching methods while 47.6% recommended the MR application. However, 95.2% of participants agreed that using MR with traditional methods would be better than either separately.

CONCLUSIONS:

Students’ neuroanatomy exam performance did not differ based on laboratory modality, though students preferred the traditional approach. Most students acknowledged the potential usefulness of MR in addition to traditional modalities. Further studies with larger sample sizes and a single location and instructor are needed to more fully elucidate the value of MR in learning neuroanatomy.
426 Effect of Visuospatial Feedback Versus Numeric Scores on Neurosurgical Tumor Resection Skills Among Medical Students in Virtual Reality Simulation Randomized Control Trial
Authors: Yilmaz Recai , Fazlollahi Ali , Winkler-Schwartz Alexander , Del Maestro Rolando
Published: March 2024

INTRODUCTION:

Virtual reality (VR) simulation can be implemented with various feedback modalities to optimize learners’ surgical skills acquisition. The systems can present benchmark scores as either a numeric report or a visuospatial performance assessment. In this context, the optimal feedback methodology to enhance learning remains undefined.

METHODS:

One hundred and twenty medical students (mean age [SD], 23.1 [3.6] years, 41% women) from four institutions were recruited to practice a simulated subpial tumor resection in five attempts. They were randomly assigned to receive one of four interventions between each attempt: (1) no feedback (n = 30), (2) numerical feedback (n = 30), (3) visual feedback (n = 29), or (4) visuospatial feedback (n = 31). Performance on the first task determined baseline. Skill was evaluated using previously established 14-expert performance benchmarks. The primary outcome was the number of performance benchmarks achieved throughout the five attempts.

RESULTS:

Participants in all feedback groups significantly improved their performance compared to baseline. Between-subjects comparison demonstrated a significant increase in the number of metrics achieved with visual (mean difference 1.80, p = 0.001) and visuospatial (mean difference 1.89, p < 0.001) feedback compared to control, and no significant increase with numeric assessment (mean difference 1.10, p = 0.093). In the third attempt, visual feedback was significantly superior to numeric assessment (mean difference 1.63, p = 0.016).

CONCLUSIONS:

Neurosurgical skill acquisition is enhanced with visual and visuospatial feedback in VR simulation training. These engaging modes of performance assessment result in more accelerated rate of benchmark acquisition compared to numerical scores alone. Further research is warranted to explore the potential benefits of visual and visuospatial feedback in other domains of surgical training.
436 Use of Ventriculostomy for Severe Traumatic Brain Injury Is Associated With Reduced Mortality Compared to Intraparenchymal Monitor Use: A Propensity Score-Matched Analysis
Authors: Mouchtouris Nikolaos , Luck Trevor , Yudkoff Clifford , Locke Katherine , Andrews Carrie Elizabeth , Shah Syed O. , Jallo Jack
Published: March 2024

INTRODUCTION:

There is a lack of data on whether intracranial pressure (ICP)-guided therapy with an intraparenchymal fiberoptic monitor (IPM) or an external ventricular drain (EVD) leads to superior mortality outcomes.

METHODS:

Retrospective analysis of patients with severe TBI that required IPM or EVD placement for ICP-guided therapy from 1/1/2010-12/31/2020. The data was obtained from the Pennsylvania Trauma Systems Foundation (PTSF) registry.

RESULTS:

A total of 2,305 patients met the inclusion criteria with 1,048 (45.5%) IPM and 1,257 (54.5%) EVD placed. A craniectomy was performed in 47.0% of the patients in the IPM cohort and 66.0% of the EVD cohort (p < 0.001). Multivariable logistic regression analysis showed that older age (OR 1.03, p < 0.001), decreasing GCS score (OR 1.16, p < 0.001), requiring craniectomy (OR 1.22, p = 0.049), and an IPM (OR 1.40, p = 0.001) were significant predictors of mortality. A propensity score-matched analysis was performed, adjusting the cohorts for age, gender, race, GCS, ISS, and craniotomy. EVD use is associated with a significant 28% decrease in inpatient mortality when compared to IPM (OR 0.72, p < 0.001). Hospital length of stay was also significantly shorter in the EVD cohort (OR 0.86, p = 0.03).

CONCLUSIONS:

A significant decrease in mortality was associated with the use of EVD in comparison to IPM based on our propensity score-matched analysis. Further investigation.
456 Arm Flexion to Overcome Gaps for Primary Radial Nerve Repair: An Anatomic Study
Authors: Thum Jasmine A. , Bazarek Stanley , Brown Justin M.
Published: March 2024

INTRODUCTION:

It is now well known that direct nerve repairs fare better than grafted nerve repairs. There is currently renewed interest in direct repair of nerves achieved by limb flexion followed by serial distraction as it is the least morbid and most easily implemented surgical technique to provide extra nerve excursion. This is especially simple in the upper extremity, which can be easily immobilized post-operatively in a sling.

METHODS:

Four fresh and 11 fixed cadaver arms with shoulder intact were dissected to determine the relationship between degrees of EF (ranged from 0-90 degrees EF) and nerve gap length overcome with proximal excursion of the distal nerve. Additional excursion from brachialis branch neurectomy was also assessed.

RESULTS:

We found an approximately linear relationship between EF and RN excursion. Compliance of fresh cadaveric nerves more closely approximated that of surgical tissue. In fresh cadavers, there was 3mm of RN excursion per 10 degrees EF in the proximal half of the arm, and 4 mm excursion per 10 degrees EF with neurectomy.

CONCLUSIONS:

Elbow flexion can significantly augment the ability to achieve an end-to-end repair of the RN. To simplify our findings, 90-degree EF should readily overcome a RN gap of 3.5 cm, and additional brachialis neurectomy allows for total RN excursion of 4.7 cm on average in the proximal arm with 90-degrees EF. Given nerve regeneration rates of 1-2 mm/day, we recommend 14-27 days prior to full elbow extension from a RN repair performed with 90-degree EF without neurectomy, and 18-36 days for repair at 90-degree EF with neurectomy.
463 Cervical Vertebral Bone Quality (C-VBQ) Score Independently Predicts Distal Junctional Kyphosis (DJK) Following Posterior Cervical Fusion
Authors: Aguirre Alexander Otilio , Soliman Mohamed A.R. , Kuo Cathleen , Ruggiero Nicco , Im Justin , Chintaluru Yaswanth , Khan Asham , Hess Ryan M. , Rho Kyungduk , Smolar David , Mullin Jeffrey Paul , Pollina John
Published: March 2024

INTRODUCTION:

Posterior cervical fusion is the surgery of choice when fusing long segments of the cervical spine. However, due to the limited presence of this pathology, there is a paucity of data in the literature about the postoperative complication of distal junctional kyphosis (DJK).

METHODS:

A retrospective analysis of consecutive set of patients who underwent posterior cervical fusion at a single hospital between June 1, 2010 and May 31, 2020. Univariate analysis was completed between DJK and non-DJK groups, with multivariate regression completed for relevant clinical variables. Simple linear regression was completed to analyze correlation between the C-VBQ score and total degrees of kyphosis angle change.

RESULTS:

Ninety-three patients were identified, of whom 19 (20.4%) had DJK and 74 (79.6%) did not. The DJK group had a significantly greater number of patients with anemia than the non-DJK group (15.8% vs. 1.4%; P = .03). The DJK group had a significantly higher C-VBQ score than the non-DJK group (2.97 ± 0.40 vs. 2.26 ± 0.46; P < .001). A significant, positive correlation was found between the C-VBQ score and the total degrees of kyphosis angle change (r2 = 0.26, P < .001). On multivariate analysis, the C-VBQ score independently predicted DJK (OR, 1.50; 95% CI, 1.28-1.76; P < .001).

CONCLUSIONS:

We found that the C-VBQ score was an independent predictive factor of DJK after posterior cervical fusion.
465 Focused Ultrasound-Mediated Blood-Spinal Cord Barrier Permeabilization: A Promising Targeted Approach for Treating Chronic Spinal Cord Injury in Rat Models
Authors: Ghaith Abdul Karim , Moinuddin F.M. , Dhar Ashis , Zamanian Cameron , Nieves Antonio Bon , Windebank Anthony J. , Bydon Mohamad
Published: March 2024

INTRODUCTION:

Focused ultrasound (FUS) with microbubble contrast agents can temporarily disrupt the blood-brain barrier (BBB), enabling drug delivery. FUS may also offer a minimally invasive method for delivering therapeutic agents to the affected area in chronic spinal cord injury (SCI) by transiently opening the blood-spinal cord barrier (BSCB).

METHODS:

Nine female Sprague-Dawley rats underwent a T9-T11 laminectomy with contusion SCI and were randomly allocated into FUS or control group. Three weeks later, FUS was administered intravenously with microbubbles. A pressure sweep was performed until ultra-harmonics were captured using a wideband hydrophone. We administered 2% Evans blue (EB) immediately after FUS confirmed the BSCB permeability. Transcardial perfusion was performed 2 hours later, and spinal cords were collected. Spectrophotometry was used to determine the EB concentration. Statistical analysis was performed using a student t-test.

RESULTS:

Five rats were treated with FUS while four were used as controls. Successful feedback control was achieved with FUS, and ultra-harmonics were observed in the FUS group at a mean peak pressure of 0.5 MPa. Macroscopic identification of EB in the spinal cord sections of animals exposed to FUS confirmed the localized opening of the BSCB. Spectrophotometry revealed an increase in EB concentration in the FUS group compared to controls: Mean EB concentration was 0.03 μg in the FUS group versus 0.016 μg in controls at 1-cm above the injury (p < 0.001); 0.27 μg versus 0.093 μg at the injury site (p < 0.001); and 0.25 μg versus 0.18 μg at 1-cm below the injury(p < 0.001).

CONCLUSIONS:

FUS increases the permeability of the BSCB in a chronic contusion SCI rat model. This suggests that FUS-mediated BSCB permeabilization may hold promise as a targeted approach for improving therapeutic outcomes in the treatment of chronic SCI.
509 Data-Driven Preoperative Hemoglobin Strata that Maximize the Likelihood of Blood Transfusion following Single-Level Lumbar Fusion Are Also Predictive of Major Complications and Deep Infections
Authors: Levy Hannon , Haft Mark , Agarwal Amil , Quan Theodore , Greenberg Marc , Raad Michael , Patel Tushar , Jain Amit
Published: March 2024

INTRODUCTION:

Optimizing patients undergoing single-level lumbar spine fusion helps reduce the use of blood transfusions which are associated with an increased risk of major complications and deep infection. Current hemoglobin thresholds for anemia severity were published in 1968 and are not surgery specific.

METHODS:

A retrospective cohort analysis was performed using a national database to identify patients undergoing primary single-level lumbar fusion with recorded hemoglobin values 30 days before surgery. Stratum-specific likelihood ratio (SSLR) analysis defined sex-based hemoglobin strata associated with the risk of 90-day postoperative blood transfusion. Each stratum was propensity-score matched to the highest identified hemoglobin stratum. Incidence rates and risk of 90-day major complications and 2-year deep infection between strata were observed.

RESULTS:

For 90-day blood transfusion, SSLR identified three female [Strata, Likelihood ratio (5.0-10.9, 2.41; 11.0-12.4, 1.35; 12.5-17.0, 0.78)] and three male hemoglobin strata (5.0-11.9, 2.95; 12.0-13.4, 1.46; 13.5-13.9, 0.71). Increased risk of 90-day major complications was associated with two female (11.0-12.4 [RR: 1.52; p < 0.001], 5.0-10.9 [RR: 3.40; p < 0.001]) and one male stratum (5.0-11.9 [RR: 2.02; p < 0.001]). Increased risk of 2-year deep infection was associated with one female (5.0-10.9 [RR: 3.67; p < 0.001]) and one male stratum (5.0-11.9 [RR: 2.11; p = 0.005]).

CONCLUSIONS:

SSLR analysis established single-level lumbar fusion-specific hemoglobin strata that maximize the likelihood of 90-day blood transfusions and predict the risk of 90-day major complication and 2-year deep infection. We recommend using these thresholds during preoperative optimization, noting the sequential increase in risk of complications starting with a hemoglobin of less than 13.5 in males and 12.5 in females.
511 Iron Oxide Nanoplatform HMC-FMX for Targeted Chemotherapeutic Treatment of Glioblastoma
Authors: Mohyeddinipour Sarah , Israel Liron , Miyaguchi Ken , Wang Hongqiang , Michel Michelot , Tusa Lavieri Miguel Eduardo , Rajiv Subashni , Watanabe Junji , Yu John S.
Published: March 2024

INTRODUCTION:

Glioblastoma multiforme (GBM), is the most common and aggressive form of primary brain tumors in adults with a high mortality rate. Despite the emergence of potent chemotherapies, clinical efficacy has been limited in part due to the blood-brain barrier (BBB). Therefore, recurrence rate is high, limiting life expectancy. Our nanoplatform is based on ferumoxytol (FMX), an FDA-approved MRI-sensitive supramagnetic iron oxide nanoparticle conjugated to heptamethine cyanine (HMC), a near infrared-flourescent ligand that specifically targets organic anion transporter polypeptides (OATP) expressed in GBM and endothelial cells.

METHODS:

To show the specificity of OATP-targeting by HMC-FMX nanoplatform, cells were pre-incubated with OATP inhibitors and then incubated with HMC-FMX. Fluorescent intensity and HMC uptake were assesed by flow cytometry. Cytotoxicity of the drug-loaded nanoparticles, HMC-FMX(SN38) and HMC-FMX(CPT) compared to SN38 and Camptothecin (CPT) in U87 cells was assessed by flow cytometry following cell staining with Annexin and 7-AAD.

RESULTS:

The HMC-FMX nanoplatform is successfully taken up by both U87 and endothelial cells. OATP inhibition significantly decreased HMC uptake (10%-30%) in comparison to control in U87 and endothelial cells. In addition, HMC-FMX(SN38) and HMC-FMX(CPT) exerted increased cytotoxic effect on U87 cells compared with SN38 and CPT alone. Furthermore, majority of apoptotic cells were observed in the HMC-positive cells in contrast to HMC-negative cells.

CONCLUSIONS:

HMC-FMX can encapsulate chemotherapeutic drugs, such as SN38 and CPT. HMC-FMX as a nanoplatform demonstrates specific, safe and efficient drug delivery through the BBB into GBM cells in vitro.
707 Associations Between Inflammatory Markers and Outcomes in SICH
Authors: Ong Shi Hui , Zheng Yilong , Nga Vincent , Teo Kejia , Yeo Tseng Tsai , Rui Lim Mervyn Jun
Published: March 2024

INTRODUCTION:

Studies have shown that higher neutrophil-lymphocyte ratio (NLR) significantly associated with poorer outcomes. However, most studies evaluated ischemic stroke and did not look at other markers such as platelet-lymphocyte ratio (PLR), platelet-white cell ratio (PWR) and platelet-neutrophil ratio (PNR). Wang et al demonstrated NLR had no correlation with mortality in spontaneous intracerebral hemorrhage (SICH).

METHODS:

We included 1001 patients with SICH diagnosed on computed tomography of the brain from January 2014 to December 2021. Good functional outcomes were defined as modified Rankin Scale (mRS) 0 to 2 while bad outcomes were defined as 3 to 6. Logistic regression was used to adjust for demographics (Model 1), cardiovascular risk factors (Model 2), bleed characteristics (Model 3) and baseline GCS (Model 4). Statistical analysis was done with R Studio.

RESULTS:

Logistic regression showed that NLR (OR: 1.03, 95% CI: 1.00-1.06, p < .05), PWR (OR: 0.98, 95% CI: 0.96-1.00, p < .05) and PNR (OR: 0.98, 95% CI: 0.97-0.99, p < .01) were significantly associated with 30-day mortality even after adjusting for confounders. However, PNR became non-significant after adjusting for bleed characteristics and GCS. When comparing 90-day functional outcome, only PWR (OR: 1.03, 95% CI: 1.01-1.04, p < .01) and PNR (OR: 1.01, 95% CI: 1.00-1.01, p < .05) demonstrated significant association even after adjusting for demographics and cardiovascular risk factors.

CONCLUSIONS:

In conclusion, NLR and PWR were independently and statistically associated with 30-day mortality. Further research on the value of ratios of inflammatory cells in prognosticating outcomes may help improve patient management.
724 Population Per State Served by a Neurosurgery Resident: A National Review
Authors: Stevenson Taylor C. , Rai Karan , Ellenbogen Richard G.
Published: March 2024

INTRODUCTION:

Neurosurgery residency remains challenging, with 7-years of post-graduate training offered at only 116 locations. It's typically the longest route to board certification of all surgical and medical specialties, yet its programs often consist of the smallest cohorts. Furthermore, the breadth of pathology and populations served by each neurological residency varies significantly.

METHODS:

Doximity residency “navigator” was used to query total residency programs that entered the 2022-2023 match cycle. U.S. state populations were collected from World Population Review Census January 2023. States were arranged from highest to lowest by census population. Each state population was divided by the NS resident positions in that state. The population per resident (PPR) were compared.

RESULTS:

California and Wyoming contained the largest and smallest state populations, respectively at 40,223,504 and 580,817. Vermont was the smallest state to contain a NS program with a population of 648,279 and 7 residency positions or roughly 92,611 PPR. California comparatively contained 151 positions or 266,381 PPR. Interestingly, New York and Florida each contain roughly 21 million people, yet they respectively contained 115,527 and 354,909 PPR. In total 65% of residents served between 127,920 to 306,528 people depending on the state.

CONCLUSIONS:

There is a wide range in the number of people served by each NS resident throughout the USA. Neurological Surgery residencies are not located uniformly by population and patients are free to travel across state boundaries. Currently the ACGME determines program expansion and creation by uniform specialty specific standards. Our data presents a new lens for discussing maximization of training opportunities across the continental United States.
756 A 3D Deep-learning Based Algorithm for Cerebral Vessel and Aneurysm Segmentation From CTA Images
Authors: Patel Tatsat , Patel Aakash , Veeturi Sricharan , Shah Munjal , Waqas Muhammad , Baig Ammad , Monteiro Andre , Pinter Nandor , Levy Elad I. , Siddiqui Adnan Hussain , Tutino Vincent
Published: March 2024

INTRODUCTION:

Computed tomography angiography (CTA) is the most widely used imaging modality for intracranial aneurysm (IA) management, yet it remains inferior to digital subtraction angiography (DSA) for IA detection, particularly of small IAs in the cavernous carotid region.

METHODS:

Using 50 paired CTA-DSA images, we trained (n = 27), validated (n = 3) and tested (n = 20) a deep-learning model (3D-DeepMedic) for cerebrovasculature segmentation from CTA. A landmark-based co-registration algorithm was used for registration and up-sampling of CTAs to paired DSAs. Segmented vessels from DSAs were used as the ground-truth. Accuracy of the model was evaluated using conventional metrics (dice similarity coefficient-DSC) and vessel-specific metrics, like connectivity-area-length (CAL). On the test cases (20 IAs), 3 experts detected and segmented IAs. For each rater, we recorded the rate of IA detection. For detected IAs, raters segmented IAs and calculated morphology parameters to quantify the differences in IA segmentation by raters to DeepMedic. The rater agreements were assessed using Krippendorf’s alpha.

RESULTS:

In testing, the DeepMedic model yielded a DSC and CAL of 0.971 ± 0.007 and 0.868 ± 0.008, respectively. The model delineated all IAs with errors <10% for all IA morphometrics. Conversely, average IA detection accuracy from raters was 0.653 (undetected IAs were present to a significantly greater degree on the ICA cavernous region and were significantly smaller). Error rates for IA morphometrics in rater-segmentations were significantly higher than in DeepMedic-segmentations, particularly for neck (p = 0.003), and surface-area (p = 0.003). For IA morphology, agreement between the raters was acceptable for metrics except UI (α=0.36) and NSI (α=0.69). The agreement between DeepMedic and ground truth was consistently higher.

CONCLUSIONS:

Our CTA segmentation algorithm provides a high-fidelity solution for CTA vessel segmentation, particularly for vessels and IAs in the carotid cavernous region.
789 The Impact of Social Determinants on Adjuvant Radiation Following Atypical Meningioma Surgery
Authors: Chisango Zvipo , Ugochukwu Obiadada , Zhi Xiaojie Jessie , Bray David Painton , Hoang Kimberly Bojanowski
Published: March 2024

INTRODUCTION:

WHO grade 2 meningiomas or ‘atypical meningiomas’ are a subset of meningioma associated with higher morbidity and mortality. Adjuvant radiotherapy is increasingly shown to improve survival and reduce recurrence in these tumors.

METHODS:

The National Cancer Database was queried for patients receiving atypical meningioma surgery between 2004 and 2019. Univariate association, univariate regression and multivariate regression were performed on 8,654 patients to assess the association between receipt of adjuvant radiation and social determinants. Secondarily, KM curves were used to compare overall patient survival between those that received radiation and those that did not.

RESULTS:

Adjuvant radiation was less likely to be administered to patients over age 65 (95% CI = 0.53-0.77) and more likely to be administered to males (95% CI = 1.07–1.38). Compared to the Southern USA, patients were more likely to receive radiotherapy in the Northeastern (95% CI = 1.40–2.05), Midwestern (95% CI =1.06–1.54), and Western parts of the United States (95% CI = 1.31–2.00). Patients residing furthest from the reporting facility were less likely to receive radiation (95% CI = 0.65–0.98). Patients with any kind of insurance were more likely to receive radiation (p = 0.048) than those without insurance. On multivariate analysis, no differences were found between racial groups regarding adjuvant radiation, however the univariate analysis demonstrated that compared to non-hispanic whites, non-hispanic blacks were less likely to receive radiation (95% CI = 0.64-0.94) and Asian/Pasic Islanders were more likely to receive radiation (95% CI = 1.03–1.79).

CONCLUSIONS:

We reveal that disparities in administration of adjuvant RT exist based on female sex, age > 65, uninsured status, distance from the treating facility, and facility regional location.
925 Concordance Between CSF Cytology and MR Imaging in the Detection of Leptomeningeal Dissemination in Patients With Medulloblastomas
Authors: Peeran Zain , Phelps Ryan R. L. , Aabedi Alexander Arash , Rios Jennifer , Reddy Alyssa , Aghi Manish Kumar , Gupta Nalin
Published: March 2024

INTRODUCTION:

In patients with medulloblastomas, the combination of CSF cytology and MR imaging is believed to be superior to either tool alone in detecting leptomeningeal dissemination (LMD). However, MRI has drastically improved since the initial assessment of this approach.

METHODS:

A retrospective review of 117 unique patients with medulloblastomas from a single institution was conducted. CSF samples and MR images obtained within 36 days of each other were included. A 3-tier system (negative, atypical/suspicious, positive) was utilized to account for equivocal findings. A total of 253 CSF-MRI pairs (range: 1-12 pairs per patient) obtained between 2000-2021 were analyzed.

RESULTS:

The mean (SD) age of this cohort was 14.1 (13.5) years (62.4% were male). Gross total resection with surgery was achieved in 64.5%, 83.7% received radiotherapy, 81.5% received chemotherapy. 16.2% were deceased, with the mean (SD) time till death being 4.6 (4.7) years following the first operation. The molecular subtypes were: SHH (17.0%), WNT (3.6%), non-WNT/non-SHH (46.6%), unknown (32.8%). There was a 60.5% concordance between CSF cytology and MRI, with no significant differences by molecular subtype. In 57.3% of cases, CSF cytology and MRI were both negative. In 1.2% of cases, CSF cytology and MRI were both equivocal. 26.9% of cases were positive on CSF cytology and/or MRI. MRI had an 86.8% sensitivity and CSF cytology had a 20.6% sensitivity for detecting LMD that was positive in CSF, MRI, or both. In 10 cases (4.0%), MRI was negative when CSF was atypical or positive. In 80 cases (31.6%), CSF was negative when MRI was positive or suspicious. In 94.5% of cases, MRI demonstrated greater or equal ability to CSF cytology in detecting LMD.

CONCLUSIONS:

MRI is superior to CSF cytology in detecting LMD but misses a small percentage of cases.
Influence of Surgical Resection on Survival in Glioblastoma with Multiple Localizations—a Multi-Center Retrospective Analysis
Authors: Jankovic Dragan , Krenzlin Harald , Dauth Alice , Lange Felipa , Keric Naureen , Ringel Florian
Published: March 2024

INTRODUCTION:

The presence of multiple localizations in glioblastoma is rare and associated with poor prognosis. The presence of a visible junction between enhancing lesions on magnetic resonance imaging (MRI) is defined as multifocal (MF), the absence of a dissemination pathway as multicentric (MC).

METHODS:

Data collection was performed as a multicenter retrospective analysis. From Jan 1, 2008, to Dec 31, 2020 patients presenting with IDH wild-type glioblastoma (CNS WHO grade 4) with multiple localizations were included. Demographic data, tumor size, Karnofsky Performance Score (KPS) before and after surgery were analyzed. EOR was measured by FLAIR and contrast-enhanced MRI. Gross total resection (GTR, residual tumor (RTM) < 5%), subtotal resection (STR, RTM < 30%), partial resection (PR, RTM > 30%), and biopsy (RTM > 75%).

RESULTS:

This study included 117 patients with a median age of 62 years. 45 (38.5%) patients had MC lesions, 72 (61.5%) MF. Median KPS on admission was similar in both subtypes. Median OS did not differ among MC and MF glioblastomas. In MF glioblastoma, GTR (p = 0.0001) and STR (p = 0.0001) significantly increased the median OS compared to PR and biopsy. Likewise, OS was increased after GTR (p = 0.0272) and STR (p = 0.0272) in MC glioblastoma, as well. Overall, resection significantly increased OS in patients with glioblastoma with multiple localizations compared to biopsy alone. In multivariate logistic regression analysis EOR and chemotherapy were significant and independent predictors of OS in MC and MF glioblastomas.

CONCLUSIONS:

These data indicate that GTR and STR positively affects OS in patients with MC and MF glioblastoma. These results argue for a more aggressive stance towards surgical treatment of these tumors with particularly poor prognosis, even when GTR is not within reach before resection.
Heterozygous CDKN2A Loss is Associated with Recurrence and Survival in High, But Not Low Grade Meningiomas
Authors: Tabor Joanna , O'Brien Joseph , Morales Valero Saul F. , Pappajohn Alexandros , McGuone Declan , Erson-Omay Zeynep , Yasuno Katsuhito , Gunel Murat , Moliterno Jennifer A.
Published: March 2024

INTRODUCTION:

Homozygous loss of CDKN2A/B is associated with more aggressive meningiomas and is now considered in the updated WHO grading criteria. The relevance of heterozygous loss (hetloss) of CDKN2A/B is less clear and the potential association of hetloss CDKN2A with aggressive meningioma phenotype remains underexplored.

METHODS:

Clinical and whole exome sequencing data for patients who underwent resection of sporadic meningiomas were analyzed.

RESULTS:

Of the 564 meningiomas included, 16 tumors harbored hetloss of CDKN2A; 7 of these were low grade (WHO grade I) and 9 high grade (grade II or III). Compared to high-grade hetloss meningiomas, low-grade ones were less likely to have an NF2 somatic driver mutation (p = 0.041) and were more common along the skull base (p = 0.005). Low-grade meningiomas with hetloss CDKN2A had more aggressive clinical characteristics compared to wild type (WT), with higher proliferative indices (p = 0.044), increased cellularity (p = 0.032) and higher copy number variations (p = 0.004) and patients were more likely to be symptomatic (p = 0.007); there was no difference in progression-free survival (PFS) (p = 0.4). High-grade hetloss CDKN2A meningiomas, however, had higher mitotic count (p = 0.014), increased chromosomal instability (p = 0.004), and higher recurrence rates (p < 0.001), as well as decreased PFS (p < 0.001) and overall survival (OS) (p = 0.002), compared to high-grade WT. Interestingly, these findings remained significant amongst high-grade hetloss CDKN2A meningiomas even when controlling for underlying NF2 mutation.

CONCLUSIONS:

Hetloss of CDKN2A is associated with more aggressive histological and genomic characteristics in both low- and high-grade meningiomas. Only high-grade meningiomas with hetloss CDKN2A, however, differ from those without the mutation in recurrence and PFS. This effect does not seem related to underlying somatic NF2 mutation. These findings may have clinical implications for high-grade meningiomas harboring heterozygous CDKN2A mutations.
The Ribbon Sign as a Radiological Indicator of Intramedullary Spinal Cord Subependymomas
Authors: Rincon-Torroella Jordina , Hersh Andrew M. , Liu Ann , Sair Haris I. , Lubelski Daniel , Bettegowda Chetan , Shimony Nir , Larry Lo Sheng-Fu , Sciubba Daniel M. , Jallo George I.
Published: March 2024

INTRODUCTION:

Intramedullary spinal cord (IMSC) subependymomas are rare World Health Organization grade 1 ependymal tumors. The potential presence of functional neural tissue within the tumor and poorly demarcated planes presents a risk to resection. Recognition of an intramedullary subependymoma on preoperative imaging can assist in operative planning and factor into the decision-making for gross- or sub-total resection. However, no definitive pathognomonic features have been reported on magnetic resonance imaging (MRI).

METHODS:

We retrospectively reviewed preoperative MRIs of patients presenting with IMSC tumors at a large tertiary academic institution between April 2005 and January 2022. The diagnosis was confirmed histologically. The “ribbon sign” was defined as a ribbon-like structure of T2 isointense spinal cord tissue interwoven between regions of T2 hyperintense tumor. The ribbon sign was confirmed by an expert neuroradiologist.

RESULTS:

MRIs from 151 patients were reviewed, including 42 (28%) astrocytomas, 82 (54%) ependymomas, 8 (5.3%) gangliogliomas, and 19 (13%) hemangioblastomas. Of the 82 ependymomas, ten patients (12%) presented with intramedullary subependymomas. The ribbon sign was demonstrated on nine (90%) patients with histologically proven subependymomas. No other tumor types displayed the ribbon sign.

CONCLUSIONS:

The ribbon sign is a distinctive imaging feature of IMSC subependymomas and indicates the presence of spinal cord tissue between eccentrically located tumor. Recognition of the sign should prompt clinicians to consider a diagnosis of subependymoma. Unlike their intracranial counterparts, resection of these lesions can be technically difficult, particularly in cases with poor demarcation between cord and tumor. Therefore, the risks and benefits of gross- vs. sub-total resection should be carefully considered and discussed with patients.
The use of click chemistry in sphingolipid research
Authors: Jamecna Denisa , Höglinger Doris
Published: March 2024

Sphingolipid dysregulation is involved in a range of rare and fatal diseases as well as common pathologies including cancer, infectious diseases or neurodegeneration. Gaining insights into how sphingolipids are involved in these diseases would contribute much to our understanding of human physiology, as well as the pathology mechanisms. However, scientific progress is hampered by a lack of suitable tools that can be used in intact systems. To overcome this, efforts have turned to engineering modified lipids with small clickable tags and to harnessing the power of click chemistry to localize and follow these minimally modified lipid probes in cells. We hope to inspire the readers of this Review to consider applying existing click chemistry tools for their own aspects of sphingolipid research. To this end, we focus here on different biological applications of clickable lipids, mainly to follow metabolic conversions, their visualization by confocal or superresolution microscopy or the identification of their protein interaction partners. Finally, we describe recent approaches employing organelle-targeted and clickable lipid probes to accurately follow intracellular sphingolipid transport with organellar precision.
Zwischen Religion und Alchemie. Der Gelehrte Ibn Arfaʿ Raʾs (fl. 12. Jh.)
Authors: Forster Regula
Published: March 2024

Alchemie
On the geometric interpretation of quaternions by cones
Authors: Scheglov Georgiy
Published: March 2024

The geometric interpretation of quaternions is considered. The visualization complexity of quaternions is due to the fact that these objects have four independent parameters. A literature analysis shows that the problem of geometric interpretation of quaternions has not been completely solved to date.

The first section provides general provisions on quaternions and the necessary notations. The second section describes the classical geometric interpretation of quaternions by arcs on a unit sphere. The third section describes a new geometric interpretation and its application to the problem of a vector finite rotation.

The geometric interpretation of the quaternion as the surface of a right circular cone is presented. This representation allow demonstrating it as a holistic object in which the scalar and vector parts are interconnected, taking into account their modules and signs.

For the considered normalized quaternion, it is easy to understanding an important entity, the quaternion versor: in general, it is a cone, which in the limiting case of a pure scalar quaternion transform into a sphere, and in the limiting case of a pure vector quaternion transform into an ordinary vector. This distinctive feature of the proposed geometric interpretation makes it possible, even when projected onto a plane, to clearly distinguish visualization of the quaternions with a nonzero scalar part from pure vector quaternions, which is difficult to do in the other known interpretations. The representation of quaternions by cones clearly demonstrates the need for a double quaternion product, when the vector is rotated around an arbitrary axis.

Images of quaternions as cones, spheres and vectors can be useful in the study of quaternion algebra, which is currently finding increasing use in engineering.
Three Approaches to Logical Correctness
Authors: Pearce Gareth R.
Published: March 2024

This paper outlines three broad ways one might think about logical correctness: the Realist approach, the One-Language approach and my own Neo-Carnapian view. Although the realist and one-language views have dominated the philosophy of logic in recent years, I argue against them, favouring of the Neo-Carnapian approach.
Asociación entre el uso del teléfono inteligente y el rendimiento académico de escolares chilenos
Authors: Leiva Ricardo , Kimber Camussetti David
Published: March 2024

Los teléfonos móviles inteligentes o smartphones pueden ser una fuente de gran disrupción en las salas de clases, ya que tienen el potencial de reducir la atención que los estudiantes prestan a sus profesores y, por lo tanto, pueden ser perjudiciales para el aprendizaje. Diversas investigaciones conducidas en Estados Unidos y el Reino Unido parecen confirmar que existe una asociación entre el uso del smartphone y el rendimiento académico de los escolares, aunque otros aseguran que el tamaño del efecto es pequeño y que habría que indagar más en las características personales de los usuarios. Para determinar si existe una relación entre el rendimiento académico de los escolares chilenos de 10 a 18 años y el uso del teléfono inteligente, se aplicó un enfoque cualitativo-cuantitativo a través de focus groups y encuestas cara a cara. Se observó que había tres variables significativas: edad a la que se recibió el primer celular, intensidad de uso diario del teléfono celular y grupo socioeconómico. No resultaron significativas ni el género ni el uso del teléfono inteligente dentro de la sala de clases. Los datos obtenidos con nuestras encuestas parecen confirmar que hay una relación entre la cantidad de horas que pasa un niño o joven con el teléfono y su promedio de notas, así como entre la edad en que los niños empiezan a usar el teléfono inteligente y su promedio de notas. En consecuencia, se puede afirmar que a mayor tiempo de uso del teléfono inteligente, peor rendimiento académico.
Fair Exploration via Axiomatic Bargaining
Authors: Baek Jackie , Farias Vivek F.
Published: March 2024

Exploration is often necessary in online learning to maximize long-term rewards, but it comes at the cost of short-term “regret.” We study how this cost of exploration is shared across multiple groups. For example, in a clinical trial setting, patients who are assigned a suboptimal treatment effectively incur the cost of exploration. When patients are associated with natural groups on the basis of, say, race or age, it is natural to ask whether the cost of exploration borne by any single group is “fair.” So motivated, we introduce the “grouped” bandit model. We leverage the theory of axiomatic bargaining, and the Nash bargaining solution in particular, to formalize what might constitute a fair division of the cost of exploration across groups. On one hand, we show that any regret-optimal policy strikingly results in the least fair outcome: such policies will perversely leverage the most “disadvantaged” groups when they can. More constructively, we derive policies that are optimally fair and simultaneously enjoy a small “price of fairness.” We illustrate the relative merits of our algorithmic framework with a case study on contextual bandits for warfarin dosing where we are concerned with the cost of exploration across multiple races and age groups.

This paper was accepted by David Simchi-Levi, data science.

Funding: This work was supported by the National Science Foundation, Division of Civil, Mechanical and Manufacturing Innovation [Grant 1727239].

Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2022.01985 .
An introduction to carrying out and appraising systematic reviews in healthcare
Authors: Davies Alan
Published: March 2024

Systematic literature reviews remain one of the most trusted sources of evidence used to inform policy and clinical decision-making. The proliferation of academic publications makes reviews increasingly essential to practitioners and policy makers as they enable them to rapidly access high-quality evidence synthesised from multiple sources. Knowledge and awareness of the structure and components of a systematic review can aid in the production of high-calibre reviews and improve the ability to appraise their quality. An overview of the main stages of carrying out a review is presented here along with frameworks and methodological considerations that will aid those producing or appraising systematic reviews.
Delivering More Efficient Fabs
Authors: Tyler Neil
Published: March 2024

As investment in new fab capacity accelerates the semiconductor industry is turning to technology to address a lack of skills, training and education. NEIL TYLER investigates
Follow The Data Flow
Authors: Schneider Stan
Published: March 2024

To make the world run better, don’t design systems around algorithms, devices, or even functions rather focus on the dataflow, according to STAN SCHNEIDER
Re-Imagining Euripides’ Medea : Pre-Colonial Indigenous Elements in Alfaro’s Mojada
Authors: Reitzammer Laurialan
Published: March 2024

Abstract: This essay examines pre-colonial Mesoamerican elements in Luis Alfaro’s Mojada , highlighting significant differences between the recently published script of the play and a version produced at the Public Theater in New York City, which I attended in summer 2019, to argue that the Public Theater production questions whether Indigenous myth and ritual can persist and function effectively in the United States in the face of the brutal and dehumanizing forces of capitalism and racism. This essay contributes to discussions of the ways in which theatrical representations of Indigeneity function across different Latinx cultures and even different versions of the same play.
Altered States: Psychedelic Experimental Cinema as Border Crossing in Bruce Conner’s LOOKING FOR MUSHROOMS
Authors: Gosse Johanna
Published: March 2024

ABSTRACT: This article offers a close examination of Bruce Conner’s LOOKING FOR MUSHROOMS (1959–1967), which is considered an archetypal instance of experimental cinema’s engagement with psychedelic counterculture. By analyzing the film’s most prominent motifs—including ethnographic views of Mexican village life, hallucinogenic mushrooms, appearances from Timothy Leary, and multiple allusions, both symbolic and literal, to the atomic bomb—and contextualizing them within Cold War discourses of race and nationhood, it argues that the film’s engagement with psychedelia is shaped by a colonialist logic of “expansion” and (self-)discovery, in which primitivist projections of Indigeneity play a constitutive role.
Sestina Obbligato, and: After Rain
Authors: Reid Erica
Published: March 2024

Abstract: “Sestina Obbligato” breaks the sestina form into a series of linked stories, each tying back to themes of music, physical contact, obligation, and a complicated relationship with a mother figure. In “After Rain,” the speaker finds it easier to deal with the discomforts of the body than to address the discomforts truly keeping her awake at night, specifically the absence of maternal feelings within herself.
Nesting
Authors: Steele Jarek
Published: March 2024

Abstract: In the memoir essay “Nesting,” a transgender man recalls the last months of his pre-transition pregnancy spent living with his then boyfriend in a converted garage infested by rats. As his due date draws near, he questions his ability to be a mother and finds himself more and more isolated. He bonds with his sister, who is also pregnant, and befriends the neighbor’s dog, who daily escapes her pen to find the only affection she’s ever known.
Catachresis
Authors: Ring Camila
Published: March 2024

Abstract: The term catachresis denotes the misuse of a word, but it has also evolved to mean using a word in a nontraditional or metaphorical way. This poem—dedicated to a child whose name evokes the tradition of poetic calling—uses the concept of catachresis to explore the evolutionary, reflexive, and self-begetting nature of birth, body, word, and poem.
Cross
Authors: Bond Bruce
Published: March 2024

Abstract: This poem, beginning with a meditation on a painting of a ship and the imaginative leap required to animate its motion, explores the threat of systemic abuse in psychological terms as the fallout of essentialism, transference, and the desire to belong.
The Strangest Thing
Authors: Rauk Katharine
Published: March 2024

Abstract: In “The Strangest Thing,” Katharine Rauk explores what it means to be lonely. This poem is a duplex, a form invented by Jericho Brown.
Protolith
Authors: Milner Surya
Published: March 2024

Abstract: This five-part essay melds the author’s personal attachment to gold with a larger rumination on the cultural valences of the metal across India and the American West. The essay considers the personal implications of claiming: a history, a stretch of land, a piece of gold.
Hourglass, and: Corduroy is a Morning in America
Authors: Whitehurst Lauren
Published: March 2024

Abstract: “Hourglass” combines images of erosion and bar-room pool to discuss concepts of breakage and the redemptive force of listening to stories, with a nod to the web/yarn-spinning spider. “Corduroy is a morning in America” uses visual, personal, and etymological impressions of corduroy—plus Reagan’s 1984 campaign line—to link a dawn ski run with concern over right-veering U.S. politics.
The Off Season
Authors: Pesut Erin
Published: March 2024

Abstract: This poem is about life at the beach in the off season.