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Spreading depolarizations (SDs) are self-propagating waves of mass depolarization that cause silencing of brain activity and have the potential to impact brain function and behavior. In the eight decades following their initial discovery in 1944, numerous publications have studied the cellular and molecular underpinning of SDs, but fewer have focused on the impact of SDs on behavior and cognition. It is now known that SDs occur in more than 60% of patients with moderate-to-severe traumatic brain injury (TBI), and their presence is associated with poor 6-month outcomes. Since cognitive dysfunction is a key component of TBI pathology and recovery, understanding the impact of SDs on behavior and cognition is an important step in developing diagnostic and therapeutic approaches. This study summarizes the known behavioral and cognitive consequences of SDs based on historical studies on awake animals, recent experimental paradigms, and modern clinical examples. This scoping review showcases our current understanding of the impact of SDs on cognition and behavior and highlights the need for continued research on the consequences of SDs.

Traumatic Brain Injury (TBI) is a significant global health concern, particularly in low- and middle-income countries (LMICs) where access to medical resources is limited. Decompressive craniectomy (DHC) is a common procedure to alleviate elevated intracranial pressure (ICP) following TBI, but the cost of subsequent cranioplasty can be prohibitive, especially in resource-constrained settings. We describe challenges encountered during the beta-testing phase of CranialRebuild 1.0, an automated software program tasked with creating patient-specific cranial implants (PSCIs) from CT images. Two pilot clinical teams in the Philippines and Ukraine tested the software, providing feedback on its functionality and challenges encountered. The constructive feedback from the Philippine and Ukrainian teams highlighted challenges related to CT scan parameters, DICOM file arrays, software limitations, and the need for further software improvements. CranialRebuild 1.0 shows promise in addressing the need for affordable PSCIs in LMICs. Challenges and improvement suggestions identified throughout the beta-testing phase will shape the development of CranialRebuild 2.0, with the aim of enhancing its functionality and usability. Further research is needed to validate the software's efficacy in a clinical setting and assess its cost-effectiveness.

Purpose: Financial restrictions limit the options for hermetically precise, patient-specific cranial implants (PSCIs) after decompressive hemicraniectomy (DHC) in low-income countries. Use of image segmentation, modeling software, and 3D printers has lowered costs associated with PSCIs. However, requirements of time and technical expertise have prevented widespread utilization. Our objective was to create a fully automated software algorithm that is able to generate a virtual model (.STL) of a negative of an implant using CT imaging following DHC., Methods: A freeware algorithm (CranialRebuild) was constructed with the following capabilities: (1) after the upload of digital imaging and communications in medicine files, the normal side is analyzed in reference to the side of DHC, (2) Boolean subtraction is used to obtain a virtual image of the desired implant, and (3) a two-piece virtual model (.STL) of the PSCI mold is generated. In four cadaveric specimens, a standard DHC was performed. Post-DHC CT imaging was used to obtain a .STL of the negative of the implant, which was then printed using poly-lactic acid (PLA). Methylmethacrylate cement was used to generate a PSCI from the mold. The PSCIs were implanted into the index specimens; cosmesis was subjectively evaluated using a 5-point Likert scale., Results: Two specimens were graded as 4/5, indicating that minor post-processing modification was needed for optimal cosmesis. Two specimens were graded as 3/5, indicating that optimal cosmesis could be obtained following moderate post-processing modification., Conclusions: CranialRebuild can be used to create hermetically precise PSCIs at a fraction of the price of third-party vendors. Validation of this technology has significant implications for the accessibility of customized cranial implants worldwide., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Background: Intramedullary spinal cord ependymomas (IMSCEs) are rare tumors that mostly occur in adults. Management strategies and related outcomes are heterogeneously reported across the literature, demanding a comprehensive analysis to standardize guidelines. We performed a systematic review of the literature on IMSCEs., Methods: A literature search was conducted using 6 databases from inception up to July 28, 2022. Studies with data on clinical characteristics, management strategies, and related outcomes in adult patients with histopathologically confirmed IMSCEs were pooled and analyzed., Results: The analysis included 69 studies comprising 457 patients (52.7% males). Mean age was 42.4 ± 7.4 years. Sensory deficit (58.0%) was the most prevalent symptom, followed by radicular pain (50.5%). Tumors mostly involved the cervical (64.4%) or thoracic (18.8%) spinal cord and were mostly World Health Organization grade II (80.5%) and classic subtype (72.4%). Gross total resection was performed in most cases (83.4%), with adjuvant radiotherapy delivered in 10.5% of cases. Progression-free survival ≥2 years was reported in 61.1% of cases, and tumor recurrence or progression was reported in only 7.0% of the patients. At last follow-up, 97.4% of patients were alive., Conclusions: IMSCEs are uncommon tumors that frequently manifest with debilitating symptoms that require surgical treatment. When feasible, gross total resection may be pursued to improve the patient's functional status and prevent tumor progression, with adjuvant radiotherapy required only in some more aggressive grade III lesions. Future studies should investigate different growth patterns and prognoses based on different IMSCE subtypes., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Parkinson disease (PD) has been recognized as responsible for concurrent spinal disorders. Surgical correction may be necessary, but the complexity of such fragile patients may require specific considerations. We systematically reviewed the literature on degenerative spine surgery in patients with PD., Methods: PubMed, Scopus, Web of Science, and Cochrane were searched according to the PRISMA guidelines to include studies reporting clinical data of patients with PD undergoing degenerative spine surgery. Clinical characteristics, treatment protocols, and outcomes were analyzed., Results: We included 22 articles comprising 442 patients (61.5% female). Mean age was 66.9 ± 3.5 years (range, 41-83 years). Mean PD duration and modified Hoehn and Yahr stage were 4.46 ± 2.39 years and 2.3 ± 0.8, respectively. Operation types included fusion (55.3%) and decompression (41.6%). Mean operated spine levels were 6.0 ± 5.08. A total of 377 postoperative complications occurred in 34.6% patients, categorized into mechanical failure (58.0%), infection (15.1%), or neurologic (10.7%). Of patients, 31.8% required surgical revisions, with an average of 1.88 ± 1.03 revisions per patient. The average normalized presurgery, postsurgery, and final aggregate numeric patient outcome scores were 0.37 ± 0.13, 0.63 ± 0.18, and 0.61 ± 0.19, respectively, with a score of 0 and 1 representing the worst and best possible score., Conclusions: Degenerative spine surgery in patients with PD is challenging, with complications and revisions occurring in up to a third of treated patients. Surgery should be offered when other treatment options have proved ineffective and is typically reserved for patients with myelopathy or significant disability. Successful outcomes depend on strong interdisciplinary support to control the movement disorder before and after surgery., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: The German Anatomist Hubert Von Luschka first described the foramina of Luschka (FOL) in 1855 as lateral holes in the fourth ventricle. By his discovery, he refuted previous beliefs about the lateral recess as blind ends of the fourth ventricle, proving the continuity of the ventricular system with the central canal of the spinal cord. In this paper, we question the outline variations of the patent parts of FOL and their consistency, drawing attention to the apparent query of the valvular mechanism of FOL., Methods: We conducted a literature review in PubMed and Google Scholar databases to review the existing literature describing the history, pertinent anatomy, and function of FOL. In addition, we reviewed the original German book written by Luschka., Results: While reading the available articles and original works regarding FOL, we noticed the developmental phases through which FOL was discovered, tracking the process from Aristotle till Luschka's discovery. We also discussed controversies and opinions about FOL's existence and function., Conclusion: FOL is halved into two compartments: choroidal and patent. The function of FOL resembles a oneway valve mechanism, and it depends on the patent slit-like part. Luschka had discovered over 20 anatomical structures, including several foramina, confusion in a debate may result from eponyms., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Surgical Neurology International.)

The benefit of antibiotic irrigation for prophylaxis against wound infections, not only for traumatic cranial injuries but also in elective neurosurgical care, has recently been called into question. Several articles have cast doubt on the utility of topical antibiotics, and recently, bacitracin irrigation was made unavailable in some US markets. The pervasive nature of antibiotic irrigation, considering the lack of evidence supporting its use, led the authors to question when and how neurosurgeons started using antibiotic irrigation in cranial neurosurgery. Through a review of historical literature, they highlight the adoption of antibiotic irrigation as it began in battlefield surgical practice, gradually leading to the modern concept of antibiotic prophylaxis in civilian and military care.

Spreading depolarizations (SDs) are massive breakdowns of ion homeostasis in the brain's gray matter and are a necessary pathologic mechanism for lesion development in various injury models. However, injury-induced SDs also propagate into remote, healthy tissue where they do not cause cell death, yet their functional long-term effects are unknown. Here we induced SDs in uninjured cortex and hippocampus of Sprague-Dawley rats to study their impact on glutamate receptor subunit expression after three days. We find that both cortical and hippocampal tissue exhibit changes in glutamate receptor subunit expression, including GluA1 and GluN2B, suggesting that SDs in healthy brain tissue may have a role in plasticity. This study is the first to show prolonged effects of SDs on glutamate signaling and has implications for neuroprotection strategies aimed at SD suppression., (© 2020. Springer Science+Business Media, LLC, part of Springer Nature.)