Acute and Long-Term Management of Blunt Cerebrovascular Injury at a Quaternary Referral Level 1 Trauma Center: The Memphis Experience and Comparison of a New Scoring System

BACKGROUND AND OBJECTIVES

The management of blunt cerebrovascular injuries (BCVIs) remains an important topic within trauma and neurosurgery today. There remains a lack of consensus within the literature and significant variation across institutions. The purpose of this study was to evaluate management of BCVI at a large, tertiary referral trauma center.

METHODS

Institutional Review Board approval was obtained to conduct a retrospective review of patients with BCVI at our Level 1 Trauma Center. Computed tomography angiography was used to identify BCVI for each patient. Patient information was collected, and statistical analysis was performed. With the included risk factors for ischemic complications, a novel scoring system based on ischemic risk, the "Memphis Score," was developed and evaluated to grade BCVI.

RESULTS

Two hundred seventeen patients with BCVI from July 2020 to August 2022 were identified. The most common mechanism of injury was motor vehicle collision (141, 65.0%). Vertebral arteries were the most common vessel injured (136, 51.1%) with most injuries occurring at a high cervical location (101, 38.0%). Denver Grade 1 injuries (89, 33.5%) and a Memphis Score of 1 were most frequent (172, 64.6%), and initial anticoagulation with heparin drip was initiated 56.7% of the time (123). Endovascular treatment was required in 24 patients (11.1%) and was usually performed in the first 48 hours (15, 62.5%). While Denver Grade (P = .019) and Memphis Score (P < .00001) were significantly higher in those patients undergoing endovascular treatment, only the Memphis Score demonstrated a significant difference between those patients who had stroke or worsening on follow-up imaging and those who did not (P = .0009).

CONCLUSION

Although BCVI management has improved since early investigative efforts, institutions must evaluate and share their data to help clarify outcomes. The novel "Memphis Score" presents a standardized framework to communicate ischemic risk and guide management of BCVI.

Epigenetics to clinicopathological features: a bibliometric analysis of H3 G34-mutant diffuse hemispheric glioma literature

PURPOSE

Pediatric-type diffuse high-grade gliomas are the leading cause of cancer-related morbidity and mortality in children. More than 30% of diffuse hemispheric gliomas (DHG) in adolescents harbor histone H3 G34 mutations and are recognized by the World Health Organization as a distinct tumor entity. By reporting bibliometric characteristics of the most cited publications on H3 G34-mutant DHG (H3 G34 DHG), we provide an overview of emerging literature and speculate where future research efforts may lead.

METHODS

One hundred fourteen publications discussing H3 G34 DHG were identified, categorized as basic science (BSc), clinical (CL), or review (R), and ranked by citation number. Various bibliometric parameters were summarized, and a comparison between article types was performed.

RESULTS

Articles within this study represent principal investigators from 15 countries and were published across 63 journals between 2012 and 2024, with 36.84% of articles originating in the United States. Overall median values were as follows: citation count, 20 (range, 0-2591), number of authors, 9 (range, 2-78), and year of publication, 2020 (range, 2012-2024). Among the top ten most cited articles, BSc articles accounted for all ten reports. Compared to CL and R articles, BSc articles were published in journals with higher impact factors.

CONCLUSION

We establish variability in bibliometric parameters for the most cited publications on H3 G34 DHG. Our findings demonstrate a paucity of high-impact and highly cited CL reports and acknowledge an unmet need to intersect basic mechanism with clinical data to inform novel therapeutic approaches.

Oncohistones and disrupted development in pediatric-type diffuse high-grade glioma

Recurrent, clonal somatic mutations in histone H3 are molecular hallmarks that distinguish the genetic mechanisms underlying pediatric and adult high-grade glioma (HGG), define biological subgroups of diffuse glioma, and highlight connections between cancer, development, and epigenetics. These oncogenic mutations in histones, now termed "oncohistones", were discovered through genome-wide sequencing of pediatric diffuse high-grade glioma. Up to 80% of diffuse midline glioma (DMG), including diffuse intrinsic pontine glioma (DIPG) and diffuse glioma arising in other midline structures including thalamus or spinal cord, contain histone H3 lysine 27 to methionine (K27M) mutations or, rarely, other alterations that result in a depletion of H3K27me3 similar to that induced by H3 K27M. This subgroup of glioma is now defined as diffuse midline glioma, H3K27-altered. In contrast, histone H3 Gly34Arg/Val (G34R/V) mutations are found in approximately 30% of diffuse glioma arising in the cerebral hemispheres of older adolescents and young adults, now classified as diffuse hemispheric glioma, H3G34-mutant. Here, we review how oncohistones modulate the epigenome and discuss the mutational landscape and invasive properties of histone mutant HGGs of childhood. The distinct mechanisms through which oncohistones and other mutations rewrite the epigenetic landscape provide novel insights into development and tumorigenesis and may present unique vulnerabilities for pHGGs. Lessons learned from these rare incurable brain tumors of childhood may have broader implications for cancer, as additional high- and low-frequency oncohistone mutations have been identified in other tumor types.

The role of neurosurgery in advancing pediatric CNS tumor care worldwide

Introduction

There is substantial inequity in survival outcomes for pediatric brain tumor patients residing in high-income countries (HICs) compared to low- and middle-income countries (LMICs). To address disparities in pediatric cancer survival, the World Health Organization (WHO) established the Global Initiative for Childhood Cancer (GICC) to expand quality care for children with cancer.

Research question

To provide an overview of pediatric neurosurgical capacity and detail the burden of neurosurgical diseases impacting children.

Material and methods

A narrative review of the current context of global pediatric neurosurgical capacity as it relates to neurooncology and other diseases relevant to children.

Results

In this article, we provide an overview of pediatric neurosurgical capacity and detail the burden of neurosurgical diseases impacting children. We highlight concerted advocacy and legislative efforts aimed at addressing unmet neurosurgical needs in children. Finally, we discuss the potential implications of advocacy efforts on treating pediatric CNS tumors and outline strategies to improve global outcomes for children with brain tumors worldwide in the context of the WHO GICC.

Discussion and conclusion

With both global pediatric oncology and neurosurgical initiatives converging on the treatment of pediatric brain tumors, significant strides toward decreasing the burden of pediatric neurosurgical diseases will hopefully be made.

The Greatest Healthcare Disparity: Addressing Inequities in the Treatment of Childhood Central Nervous System Tumors in Low- and Middle-Income Countries

The antithesis between childhood cancer survival rates in low- and middle-income countries (LMIC) and high-income countries (HIC) represents one of healthcare's most significant disparities. In HICs, the 5-year survival rate for children with cancer, including most brain tumors, exceeds 80%. Unfortunately, children in LMICs experience far worse outcomes with 5-year survival rates as low as 20%. To address inequities in the treatment of childhood cancer and disease burden globally, the World Health Organization (WHO) launched the Global Initiative for Childhood Cancer. Within this initiative, pediatric low-grade glioma (LGG) represents a unique opportunity for the neurosurgical community to directly contribute to a paradigm shift in the survival outcomes of children in LMICs, as many of these tumors can be managed with surgical resection alone. In this chapter, we discuss the burden of pediatric LGG and outline actions the neurosurgical community might consider to improve survival for children with LGG in LMICs.

The role of neurosurgeons in global public health: the case of folic acid fortification of staple foods to prevent spina bifida

OBJECTIVE

The global neurosurgery movement arose at the crossroads of unmet neurosurgical needs and public health to address the global burden of neurosurgical disease. The case of folic acid fortification (FAF) of staple foods for the prevention of spina bifida and anencephaly (SBA) represents an example of a new neurosurgical paradigm focused on public health intervention in addition to the treatment of individual cases. The Global Alliance for the Prevention of Spina Bifida-F (GAPSBiF), a multidisciplinary coalition of neurosurgeons, pediatricians, geneticists, epidemiologists, food scientists, and fortification policy experts, was formed to advocate for FAF of staple foods worldwide. This paper serves as a review of the work of GAPSBiF thus far in advocating for universal FAF of commonly consumed staple foods to equitably prevent SBA caused by folic acid insufficiency.

METHODS

A narrative review was performed using the PubMed and Google Scholar databases.

RESULTS

In this review, the authors describe the impact of SBA on patients, caregivers, and health systems, as well as characterize the multifaceted requirements for proper spina bifida care, including multidisciplinary clinics and the transition of care, while highlighting the role of neurosurgeons. Then they discuss prevention policy approaches, including supplementation, fortification, and hybrid efforts with folic acid. Next, they use the example of FAF of staple foods as a model for neurosurgeons' involvement in global public health through clinical practice, research, education and training, and advocacy. Last, they describe mechanisms for involvement in the above initiatives as a potential academic tenure track, including institutional partnerships, organized neurosurgery, neurosurgical expert groups, nongovernmental organizations, national or international governments, and multidisciplinary coalitions.

CONCLUSIONS

The role of neurosurgeons in caring for children with spina bifida extends beyond treating patients in clinical practice and includes research, education and training, and advocacy initiatives to promote context-specific, evidence-based initiatives to public health problems. Promoting and championing FAF serves as an example of the far-reaching, impactful role that neurosurgeons worldwide may play at the intersection of neurosurgery and public health.

Pediatric Neurosurgical Capacity for the Care of Children With CNS Tumors Worldwide: A Cross-Sectional Assessment

PURPOSE

Efforts to address inequities in the treatment of pediatric CNS tumors and the burden of childhood cancer globally have prompted the designation of low-grade glioma as one of six index cancers for the World Health Organization Global Initiative for Childhood Cancer. Understanding the importance of neurosurgical interventions and evaluating pediatric neurosurgical capacity may identify critical interventions to improve outcomes for children with low-grade glioma and other CNS tumors.

METHODS

An online, cross-sectional survey assessing pediatric neurosurgical practice and capacity was distributed to members of the International Society of Pediatric Neurosurgery. The survey included 36 items covering domains including patient volume, available infrastructure, scope of practice, case distribution, and multidisciplinary care.

RESULTS

Responses from 196 individuals from 61 countries, spanning all WHO regions, were included. Ninety-six (49.0%) were from high-income countries, 57 (29.1%) were from upper-middle-income countries, 42 (21.4%) were from lower-middle-income countries (LMICs), and 1 was (0.5%) from a low-income country. Most respondents had a catchment population of ≥ 1 million and indicated the availability of basic neurosurgical resources such as a dedicated neurosurgical operating theater and surgical microscope. The presence of a neurosurgical intensive care unit, inpatient rehabilitation services, and infection monitoring showed similar availability across country groups. Quantitative scoring of 13 infrastructure and service items established that fewer resources were available in low-income countries/LMICs and upper-middle-income countries compared with high-income countries. The volume of pediatric CNS tumor cases and case distribution did not vary according to World Bank country groups.

CONCLUSION

This study provides a comprehensive evaluation of pediatric neurosurgical capacity across the globe, establishing variability of resources on the basis of the country income level. Our findings suggest that pediatric neurosurgeons in LMICs may benefit from key neurosurgical instrumentation and increased support for multidisciplinary brain tumor programs and childhood cancer research efforts.

Effects of stimulus salience and methamphetamine on choice reaction time in the rat: central tendency versus distribution skew

Stimulants decrease reaction time in humans as well as laboratory rats. This effect is seen as a decrease in average reaction time or a shift in the distribution peak towards shorter reaction times. However, response-time distributions are typically skewed, exhibiting a positive tail. Our goal for this project was to develop a method of analyzing reaction-time distributions in the rat which will allow us to study systematically measures of central tendency and distribution skew. This analysis subdivided reaction time into initiation time and movement time, and also subdivided the response time distributions into distribution mode and distribution skew. Rats were trained on a two-choice visual reaction-time task. We then evaluated the effects of stimulus salience and methamphetamine (METH) treatment (vehicle, 0.25, 0.5, 1.0, and 1.5 mg/kg) on measures of distribution mode and skew. Stimulus salience decreased initiation time mode, initiation time skew and movement time skew, but had no effect on movement time mode. METH had a greater effect on skew for the initiation time distribution and a greater effect on mode for the movement time distribution. This analysis will serve as a useful method of determining whether initiation time and movement time, as well as distribution mode and distribution skew, represent different behavioral processes in the rat.

Anxiolytic effects of kava extract and kavalactones in the chick social separation-stress paradigm

RATIONALE

Piper methysticum extract (kava kava) possesses numerous therapeutic properties, but it is unknown which of its principle constituents (kavalactones) subserve such effects.

OBJECTIVES

This experiment sought to characterize the putative anxiolytic properties of P. methysticum extract and its six principle kavalactones in the chick social separation-stress paradigm.

METHODS

Eight-day-old chicks received intraperitoneal injections of either vehicle, chlordiazepoxide (5.0 mg/ml per kg), P. methysticum extract (containing 30% kavalactones), kavain, dihydrokavain, methysticin, dihydromethysticin, yangonin, or desmethoxyyangonin (30 mg/ml per kg for kava compounds) 30 min prior to being tested in the presence of two conspecifics or in isolation for a 3-min observation period. Latency to adopt a ventral recumbent posture to index sedation, number of vocalizations to index separation distress, and a composite pain score (in response to 50 microliters 0.10% formalin injection into the plantar surface of the foot) to index stress-induced analgesia served as dependent measures.

RESULTS

Both chlordiazepoxide and P. methysticum extract attenuated separation-induced distress vocalizations and stress-induced analgesia. Dihydrokavain attenuated separation-induced distress vocalizations.

CONCLUSIONS

These findings suggest that the anxiolytic effects of P. methysticum extract may be mediated, in part, by dihydrokavain.

Long-term effects of a high-dose methamphetamine regimen on subsequent methamphetamine-induced dopamine release in vivo

Rats were treated with a high-dose methamphetamine (METH) regimen (40 mg/kg/injection, four times at 2-h intervals) or a saline regimen (four injections at 2-h intervals). Temperature related measures taken during the high-dose METH treatment were maximum core temperature and minimum chamber temperature. Fourteen rats (METH N=7; Saline N=7) were implanted with in-vivo dialysis probes 4-7 weeks post-regimen (average=6 weeks). The next day, they received a challenge dose of METH (4.0 mg/kg) and dopamine release was measured. Results showed a significant decrease in challenge-induced dopamine release in rats previously treated with the high-dose METH regimen. These findings demonstrate a functional deficit in the dopamine system 6 weeks after high-dose METH treatment. Temperature-related measures taken during the high-dose regimen were not correlated with METH-induced dopamine release 6 weeks later. An additional group of rats were sacrificed 6 weeks after the high-dose regimen (METH N=12; Saline N=10), and their brains was analyzed for dopamine and serotonin concentrations. Tissue concentrations of dopamine were significantly depleted in striatum and nucleus accumbens/olfactory tubercle, but not septum, hypothalamus, or ventral mid-brain 6 weeks after the high-dose regimen. Tissue concentrations of serotonin were also significantly depleted in striatum, nucleus accumbens/olfactory tubercle, hippocampus, somatosensory cortex, but not septum, hypothalamus or ventral mid-brain. Significant correlations between the temperature-related measures and post-mortem neurotransmitter tissue concentrations were region and transmitter dependent.

Anxiolytic properties of botanical extracts in the chick social separation-stress procedure

RATIONALE

The recent growth in sales of natural products labeled as dietary supplements in the United States has renewed scientific interest in the study of the therapeutic effects of multi-component botanical products.

OBJECTIVES

This study sought to determine whether botanical extracts derived from the Rutaceae family, Acori graminei, the Magnoliaceae family, Alchemilla vulgaris and Primula veris, which had previously been identified in bioassays as having potential anxiolytic activity, were active in the chick social separation-stress procedure.

METHODS

Eight-day-old chicks received IP injections of test articles 30 min before being tested in the presence of two social companions or in isolation for a 3-min observation period. Dependent measures were: a) latency to adopt a ventral recumbent posture to index sedation, b) number of vocalizations to index separation-distress and c) a composite pain score (comprised of footlift frequency and footlift duration in response to 50 microl of 0.10% formalin injected into the plantar surface of the foot) to index stress-induced analgesia.

RESULTS

Proprietal extracts NPS00033 from the Rutaceae plant family and NPS00039 (Relora) from the Magnoliaceae plant family screened positive in this chick model without causing sedation.

CONCLUSIONS

These results suggest that botanical extracts Relora and NPS00033 may be useful in modulating anxiety states.

Benzodiazepine receptor function in the chick social separation-stress procedure

The role of benzodiazepine (BZ) receptors in modulating social separation-induced distress vocalizations (DVocs) and stress-induced analgesia (SIA) were examined in 8-day-old cockerels (Gallus gallus). In Experiment 1, the BZ agonist chlordiazepoxide (CDP; 5.0 mg/kg) reversed both DVocs and SIA in isolated chicks. Coadministration of the BZ antagonist flumazenil (0.01, 0.03, or 0.10 mg/kg) reversed CDP anxiolytic effects. In Experiment 2, the BZ agonists alprazolam (ALP; 0.065, 0.125, 0.25, or 1.50 mg/kg) and lorazepam (LOR; 0.125, 0.25, 0.50, or 1.0 mg/kg) dose dependently reversed social separation-induced DVocs and SIA. The ED50s for ALP and LOR in attenuating DVocs were 0.19 and 0.34 mg/kg, respectively. These data strongly support the theory that CDP anxiolytic effects are mediated by BZ receptor activity in the chick social separation procedure (Experiment 1) and that this model is sensitive to BZ agonists of different potencies (Experiment 2).