Cell Transplantation for Repair of the Spinal Cord and Prospects for Generating Region-Specific Exogenic Neuronal Cells.

Spinal cord injury (SCI) is associated with currently irreversible consequences in several functional components of the central nervous system. Despite the severity of injury, there remains no approved treatment to restore function. However, with a growing number of preclinical studies and clinical trials, cell transplantation has gained significant potential as a treatment for SCI. Researchers have identified several cell types as potential candidates for transplantation. To optimize successful functional outcomes after transplantation, one key factor concerns generating neuronal cells with regional and subtype specificity, thus calling on the developmental transcriptome patterning of spinal cord cells. A potential source of spinal cord cells for transplantation is the generation of exogenic neuronal progenitor cells via the emerging technologies of gene editing and blastocyst complementation. This review highlights the use of cell transplantation to treat SCI in the context of relevant developmental gene expression patterns useful for producing regionally specific exogenic spinal cells via in vitro differentiation and blastocyst complementation.

The Infratrigeminal Suprafloccular Approach to Intrapontine Lesions: An Anatomical Overview and Relevance for the Approach to Intrapontine Lesions.

Background and objectives Brainstem lesions have long been considered complex pathologies that may lead to permanent deficits or life-threatening complications, posing significant challenges for surgical removal. Among these lesions, intrapontine lesions are particularly challenging in the field of neurosurgery. However, with advancements in microsurgical anatomy knowledge and technology, these lesions have become more amenable to surgical treatment. In this study, the authors examine an infratrigeminal suprafloccular approach, which has been shown to be a safe surgical route, resulting in fewer postoperative complications, while evaluating the anatomical nuances of the approach and route. Methods Twenty cadaveric brainstem specimens were analyzed to assess the anatomy, focusing on the lateral aspect of the pons as a potential safe entry zone for intrapontine lesions. The authors consistently analyzed twenty brainstem specimens, carefully examining the pontine microsurgical anatomy. A triangular area of entrance was measured, with three sides or walls (X, Y, and Z) aiming to identify the safe zone that would spare the distinct pontine nuclei, ascending sensory pathways, corticospinal, corticonuclear, and corticopontine tracts of the brainstem. An illustrative case was adapted to the described safe entry zone for corroboration purposes. Results The authors measured three distinct lines on the lateral surface of the pons, named X, Y, and Z, forming a triangle in shape. Line X extended from the midpoint anteroposteriorly of the flocculus of the cerebellum to the apparent trigeminal exit in the lateral aspect of the pons. Line Y ran from the trigeminal exit in the pons to the apparent exit of the facial-vestibulocochlear complex in the far lateral aspect of the pontomedullary sulcus in the cerebellopontine fissure. Line Z represented the measurement from the vestibulocochlear complex to the midpoint anteroposteriorly of the flocculus of the cerebellum. The mean measurements were as follows: X = 14.41mm (range: 10mm to 20mm), Y = 13.1mm (range: 10mm to 21mm), and Z = 3mm (range: 2mm to 5mm). The mean surface area of the analyzed specimens within the triangle (formed by X, Y, and Z) was 20.1mm² (range: 10mm² to 40mm²). This area was identified as a safe zone for the entry of microsurgical approaches to intrapontine lesions, involving less retraction of the anterior pons and potentially sparing critical structures, such as the corticospinal tracts, pontine perforating arteries, tegmentum pontis, cranial nerve nuclei, substantia reticulata dorsally, and transverse pontine fibers. Microsurgical anatomical findings, combined with intraoperative monitoring in an illustrative case, consistently demonstrated that this entry area predicted less functional instability of the analyzed tracts and resulted in fewer postoperative complications. Conclusion Deep-seated pontine lesions present a complex range of pathologies with a high potential for devastating outcomes, particularly those involving hemorrhage. This study identifies and describes a presumed safe entry zone that allows for the creation of a surgical corridor for biopsy or microsurgical resection of these lesions, reducing morbidity in a previously considered impenetrable region.

The Expanding Role of ChatGPT (Chat-Generative Pre-Trained Transformer) in Neurosurgery: A Systematic Review of Literature and Conceptual Framework.

The objective of this study is to explore the use of ChatGPT (Chat-Generative Pre-Trained Transformer) in neurosurgery and its potential impact on the field. The authors aim to discuss, through a systematic review of current literature, how this rising new artificial intelligence (AI) technology may prove to be a useful tool in the future, weighing its potential benefits and limitations. The authors conducted a comprehensive and systematic literature review of the use of ChatGPT and its applications in healthcare and different neurosurgery topics. Through a systematic review of the literature, with a search strategy using the databases such as PubMed, Google Scholar, and Embase, we analyzed the advantages and limitations of using ChatGPT in neurosurgery and evaluated its potential impact. ChatGPT has demonstrated promising results in various applications, such as natural language processing, language translation, and text summarization. In neurosurgery, ChatGPT can assist in different areas such as surgical planning, image recognition, medical diagnosis, patient care, and scientific production. A total of 128 articles were retrieved from databases, where the final 22 articles were included for thorough analysis. The studies reviewed demonstrate the potential of AI and deep learning (DL), through language models such as ChatGPT, to improve the accuracy and efficiency of neurosurgical procedures, as well as diagnosis, treatment, and patient outcomes across various medical specialties, including neurosurgery. There are, however, limitations to its use, including the need for large datasets and the potential for errors in the output, which most authors concur will need human verification for the final application. Our search demonstrated the potential that ChatGPT holds for the present and future, in accordance with the studies' authors' findings herein analyzed and expert opinions. Further research and development are required to fully understand its capabilities and limitations. AI technology can serve as a useful tool to augment human intelligence; however, it is essential to use it in a responsible and ethical manner.

A Closer Look Into Brazil's Healthcare System: What Can We Learn?

Brazil's healthcare system has made significant progress in recent years but still faces major challenges. In this editorial, we examine the greatest flaws and achievements of Brazil's healthcare system, focusing on population coverage, quality metrics, spending over the last ten years, and estimates of per capita spending over the next decade. We discuss the role of the government, private sector, and civil society in shaping Brazil's healthcare landscape and provide recommendations for improvement. Despite the challenges, Brazil has made impressive strides in healthcare, such as the implementation of the family health program, which has improved primary care access and reduced infant mortality rates. However, much work remains to be done, and Brazil must prioritize investment in healthcare infrastructure, workforce development, and the integration of digital technologies to ensure universal access to quality care for all.

After the Knife: A Detailed Roadmap for Vestibular Schwannoma Resection in the Semi-Sitting Position - How I do it.

BACKGROUND: Vestibular schwannoma surgery remains a neurosurgical challenge, with known risks, dependent on a number of factors, from patient selection to surgical experience of the team. The semi-sitting position has gained popularity as an alternative to the traditional supine position for vestibular schwannoma resection due to potential advantages such as improved surgical exposure due to clearer surgical field and anatomical orientation. However, there is a lack of standardized protocols for performing the procedure in the semi-sitting position, leading to variations in surgical techniques and outcomes. METHODS: In this study, we aimed to establish a standardized approach for vestibular schwannoma resection using the semi-sitting position. Initiating after final position for semi-sitting, the authors have divided the surgical steps into five major parts for improved understanding and replication. Surgical techniques were analyzed through one hundred steps to identify commonalities, determining the optimal procedural steps for the semi-sitting position using surgical video for visual conceptualization. RESULTS: The analysis described one hundred steps for vestibular schwannoma resection in the semi-sitting position, with visual demonstration of the various parts of the procedure through surgical videos. Specific recommendations for each step were outlined, including appropriate approach, monitoring strategies, and tumor and posterior fossa structures manipulation. Five major parts of the procedure were identified, leading to a reproducible standardization of the surgical procedure of vestibular schwannoma resection in the semi-sitting position. CONCLUSIONS: This study provides a comprehensive standardized protocol for the semi-sitting procedure in vestibular schwannoma resection. By establishing a consistent approach, surgeons can minimize variations in surgical techniques and improve patient outcomes. The identified steps and recommendations can serve as a valuable resource for surgical teams involved in vestibular schwannoma resection and facilitate the dissemination and reproducibility of best practices.

Transplanting Microglia for Treating CNS Injuries and Neurological Diseases and Disorders, and Prospects for Generating Exogenic Microglia.

Microglia are associated with a wide range of both neuroprotective and neuroinflammatory functions in the central nervous system (CNS) during development and throughout lifespan. Chronically activated and dysfunctional microglia are found in many diseases and disorders, such as Alzheimer's disease, Parkinson's disease, and CNS-related injuries, and can accelerate or worsen the condition. Transplantation studies designed to replace and supplement dysfunctional microglia with healthy microglia offer a promising strategy for addressing microglia-mediated neuroinflammation and pathologies. This review will cover microglial involvement in neurological diseases and disorders and CNS-related injuries, current microglial transplantation strategies, and different approaches and considerations for generating exogenic microglia.

Before the Knife: A Detailed Step-by-Step Description of an Optimized Semi-Sitting Position in Posterior Fossa Surgery.

BACKGROUND: In an ample armamentarium in neurosurgery, the semi-sitting position has produced debate regarding its benefits and risks. Although the position is apparently intuitive, many have abandoned its use since its initial inception, because of reported complexity and potential complications, leading to impracticality. However, through standardization, it has been shown not only to be safe but to carry with it many advantages, including less risk of secondary neurovascular injuries and better visualization of the surgical field. As with any surgical technical nuance, the semi-sitting position has advantages and disadvantages that must be weighed before the decision is made to adopt it or not, not only in a case-by-case scenario but also from a departmental standpoint. As we attempt to show, the advantages from a standardized approach for the semi-sitting position in experienced institutions may be more than sufficient to significantly outweigh the disadvantages, making it the preferable option for most, although not all, posterior fossa surgical interventions. METHODS: In the present study, we aim to elaborate a straightforward narrative of the steps before incision, in an attempt to simplify the complexity of the position, alleviating its disadvantages and exponentially concentrating on its benefits. In nearly 100 steps, we carefully describe the points that culminate with the skin incision, initiating the intraoperative part of the procedure. Each step, therefore, is detailed in full, not in an effort to create a strict manual of the semi-sitting position but rather to facilitate understanding and put the technique into effect in a real-life scenario, thus simplifying what some depict as complex and time consuming. CONCLUSIONS: Although several of the steps described are also relevant and integral parts of other surgical positioning, we intend to create a protocol, in a stepwise fashion, to allow facilitated following, to be easily implemented in departments with different levels of experience. The steps comprise nursing care through to electrophysiologic and anesthesiologic approaches, along with neurosurgical cooperation, making it a team approach, not only to avoid position-related complications but also to optimize preoperative standardization, constructing a safe, efficient, and patient-centered scenario, to set the best possible stage for the next step: the intraoperative part of the intervention.

Cell Reprogramming for Regeneration and Repair of the Nervous System.

A persistent barrier to the cure and treatment of neurological diseases is the limited ability of the central and peripheral nervous systems to undergo neuroregeneration and repair. Recent efforts have turned to regeneration of various cell types through cellular reprogramming of native cells as a promising therapy to replenish lost or diminished cell populations in various neurological diseases. This review provides an in-depth analysis of the current viral vectors, genes of interest, and target cellular populations that have been studied, as well as the challenges and future directions of these novel therapies. Furthermore, the mechanisms by which cellular reprogramming could be optimized as treatment in neurological diseases and a review of the most recent cellular reprogramming in vitro and in vivo studies will also be discussed.

Moyamoya disease and syndrome: a review.

Moyamoya disease is a chronic occlusive cerebrovascular disease that is non-inflammatory and non-atherosclerotic. It is characterized by endothelial hyperplasia and fibrosis of the intracranial portion of the carotid artery and its proximal branches, leading to progressive stenosis and occlusion, often clinically manifesting as ischemic or hemorrhagic stroke with high rates of morbidity and mortality. On cerebral angiography, the formation of collateral vessels has the appearance of a puff of smoke (moyamoya in Japanese), which became more conspicuous with the refinement of modern imaging techniques. When there is associated disease, it is known as moyamoya syndrome. Treatments are currently limited, although surgical revascularization may prevent ischemic events and preserve quality of life. In this review, we summarize recent advances in moyamoya disease, covering aspects of epidemiology, etiology, presentation, imaging, and treatment strategies.

A doença de moyamoya, ou doença cerebrovascular oclusiva crônica, é uma afecção não inflamatória e não aterosclerótica, caracterizada por hiperplasia endotelial e fibrose dos segmentos intracranianos das artérias carótidas internas e da porção proximal de seus ramos. Isso provoca estenose progressiva e oclusão, frequentemente manifestada clinicamente como isquemia cerebral ou hemorragia intracraniana, com alta morbimortalidade. A formação compensatória de vasos colaterais produz, na angiografia encefálica, um aspecto de nuvem de fumaça (moyamoya, em japonês). Quando existe doença subjacente que possa estar relacionada, a doença recebe o nome de síndrome de moyamoya. Embora a incidência esteja aumentando graças aos novos métodos diagnósticos, as estratégias terapêuticas ainda são limitadas. O diagnóstico precoce permite cirurgias de revascularização cerebral que podem evitar novos acidentes vasculares e melhorar a qualidade de vida. Nesta revisão são apresentados os avanços recentes sobre a doença de moyamoya, citando aspectos de epidemiologia, etiologia, apresentação, exames diagnósticos e tratamento.

Moyamoya disease and syndrome: a review / Doença e síndrome de moyamoya: uma revisão

Abstract Moyamoya disease is a chronic occlusive cerebrovascular disease that is non-inflammatory and non-atherosclerotic. It is characterized by endothelial hyperplasia and fibrosis of the intracranial portion of the carotid artery and its proximal branches, leading to progressive stenosis and occlusion, often clinically manifesting as ischemic or hemorrhagic stroke with high rates of morbidity and mortality. On cerebral angiography, the formation of collateral vessels has the appearance of a puff of smoke (moyamoya in Japanese), which became more conspicuous with the refinement of modern imaging techniques. When there is associated disease, it is known as moyamoya syndrome. Treatments are currently limited, although surgical revascularization may prevent ischemic events and preserve quality of life. In this review, we summarize recent advances in moyamoya disease, covering aspects of epidemiology, etiology, presentation, imaging, and treatment strategies.

RESUMO A doença de moyamoya, ou doença cerebrovascular oclusiva crônica, é uma afecção não inflamatória e não aterosclerótica, caracterizada por hiperplasia endotelial e fibrose dos segmentos intracranianos das artérias carótidas internas e da porção proximal de seus ramos. Isso provoca estenose progressiva e oclusão, frequentemente manifestada clinicamente como isquemia cerebral ou hemorragia intracraniana, com alta morbimortalidade. A formação compensatória de vasos colaterais produz, na angiografia encefálica, um aspecto de nuvem de fumaça (moyamoya, em japonês). Quando existe doença subjacente que possa estar relacionada, a doença recebe o nome de síndrome de moyamoya. Embora a incidência esteja aumentando graças aos novos métodos diagnósticos, as estratégias terapêuticas ainda são limitadas. O diagnóstico precoce permite cirurgias de revascularização cerebral que podem evitar novos acidentes vasculares e melhorar a qualidade de vida. Nesta revisão são apresentados os avanços recentes sobre a doença de moyamoya, citando aspectos de epidemiologia, etiologia, apresentação, exames diagnósticos e tratamento.

Trigeminal Cave Brain Metastasis from Prostate Adenocarcinoma: Case Report and Review of the Literature

The present study presents the case of a 66-year-old patient diagnosed with prostate adenocarcinoma 4 years earlier and treated with prostatectomy, radiotherapy, chemotherapy and hormonetherapy but still displaying high prostate-specific antigen (PSA) levels. The patient complaints were double vision and headaches. Upon physical examination, he displayed 6th cranial nerve paresis and 5th cranial nerve paresthesia. Amagnetic resonance imaging (MRI) exam was performed, which revealed a mass on the right trigeminal cave. The patient underwent surgical removal of the tumor, and the pathological analysis of the specimen established metastatic prostate cancer as the diagnosis. Brainmetastases fromprostate cancer are extremely rare and mark advanced disease, with immune system failure and blood-brain barrier breach. Prostate-specific antigen levels do not correlate with the possibility of metastatic disease. Prostate adenocarcinoma is the histologic typemost commonly associated with brainmetastases,with themeninges being more frequently affected, followed by the brain parenchyma. The neurological symptoms more often displayed are non-focal, such as headaches and mental confusion. Surgery associated with radiotherapy is the most validated treatment.

Endovascular Neurosurgery in the Northern Macro-Region of Rio Grande do Sul: Part I

Introduction The city of Passo Fundo, in the north of the Rio Grande do Sul state, has been standing out in the health care field for many years. The state has become a reference in endovascular interventional neuroradiology. We will cover 10 years of experience in this area and divide our observations in 3 parts: cerebral angiograms (part I), carotid angioplasties (part II) and intracranial aneurysms (part III). The goal of part I is to statistically assess the cerebral angiograms, their indications, risks and complications, as well as to do a technical review. Materials and Methods A retrospective study from 2005 to 2015 with a total of 5,567 interventional neuroradiology procedures performed. A total of 4,114 angiograms, 639 embolizations of intracranial aneurysms, 414 carotid angioplasties, 143 embolizations of cerebral arteriovenous malformations, 32 embolizations of dural arteriovenous fistulas, 102 cerebral vasospasm treatments, 21 treatments of epistaxis, 36 embolizations of craniocervical tumor, 25 thrombolysis of ischemic stroke, 18 vertebroplasties and 13 embolizations of arteriovenous malformations of the face. Results A total of 4,084 procedures performed, 21,811 vessels studied, average vase 7.62/2.82 vessel and patient/procedure. Of these, 2,536 were diagnostic procedures and 1,548 angiographic controls. Of the total, 1,188 patients received only an angiogram, 27.14% of which were therapeutic procedures. We obtained a total of 3.89% complications: 2.33% reflection vasovagal, 0.56% allergic skin reaction, anaphylactic shock 0.07%, 0.27% femoral hematoma, 0.26% transient neurological deficit, 0.12% permanent neurological deficit and no case of death. Conclusion Cerebral angiography in adults, children and infants is a safe procedure with low risk of permanent neurological complications.

Concomitant Occurrence of Vestibular Schwannoma and Epidermoid Cyst in Neurofibromatosis: Case description and Review of the Literature

We report a case of a 16-year-old female patient harboring neurofibromatosis type 2 who presented with bilateral hearing impairment, which was on the left side, as well as facial paresis (House-Brackmann grade III) and ataxic gait. A magnetic resonance imaging (MRI) exam evidenced bilateral lesions in the cerebellopontine angles (CPAs) with extension into the internal acoustic meatus, and an additional lesion in the right CPA with radiological characteristics of an epidermoid cyst. The patient was submitted to microsurgical resection, confirming a collision of a vestibular schwannoma and an epidermoid cyst in the right CPA. In the present case report, we describe the first case reported in the literature with preoperative diagnostic work-up, intraoperative findings, postoperative course of the patient, as well as a detailed literature review of these specific coinciding pathologies, denoting the importance of further genomic studies regarding multiple central nervous system (CNS) lesions.

Relatamos o caso de uma paciente de 16 anos de idade com neurofibromatose tipo II com deficiência auditiva bilateral, pior no ouvido esquerdo, assim como paresia facial (HouseBrackmann grau III) e ataxia. Estudo de ressonância magnética comprovou lesão bilateral nos ângulos cerebelopontinos (ACPs) com extensão ao meato acústico interno, e uma lesão adicional no ACP direito com características radiológicas de um cisto epidermoide. A paciente foi submetida a ressecção microcirúrgica, confirmando a colisão de um schwannoma vestibular com um cisto epidermoide no ACP direito. No presente estudo, descrevemos o primeiro caso relatado na literatura com trabalho diagnóstico pré-operatório, resultados intraoperatórios, evolução da paciente no pós-operatório, assim como revisão detalhada da literatura específica sobre essas patologias, demonstrando a importância de mais estudos genômicos sobre as múltiplas lesões do sistema nervoso central (SNC).

Orbital Lymphangioma: Case Report and Management Paradigms

Introduction Lymphangioma is a rare congenital vascular malformation of the head and neck region isolated from the systemic circulation. It has a benign etiology, and represents 1­3% of all orbital tumors. These hamartomas often present in the pediatric population with a slightly female predilection. They have a lymphocytic composition, and may increase in size with episodes of viral infection, causing proptosis. Discussion The management of this lesion is controversial, hardly curative, and depends on the clinical presentation. The treatment options include partial surgical resection of the major cyst, needle aspiration, surgical debulking, systemic steroids, sildenafil, intralesional injection of the sclerosing agents, and local radiotherapy. Case Report In the present report, we describe an uncommon case of lymphangioma in a 6-year-old female who was first submitted to neurosurgery for tumor resection and received sildenafil therapy later, with promising results. Conclusion The treatment of orbital lymphangiomas remains a controversial topic, and the use of sildenafil along with needle aspiration and microsurgical removal is a viable option of treatment. However, many issues, such as the ideal duration of the therapy, the dosage regimen and the recurrence rate, still remain unclear. Our case report adds promising data on this pathology, even though larger trials are needed to properly elucidate the remaining questions.

Introdução Linfangioma é uma malformação vascular rara congênita da cabeça e da região cervical isolada da circulação sistêmica. Apresenta uma etiologia benigna e representa 1­3% de todos tumores orbitais. Estes hematomas geralmente se apresentam na população pediátrica com uma pequena predileção pela população feminina. Têm uma composição linfocítica e podem aumentar em tamanho com episódios de infecções virai causando proptose. Discussão O manejo destas lesões é controverso, dificilmente curativo e depende na apresentação clínica. Opções de tratamento compreende ressecção cirúrgica parcial do cisto de maior volume, aspiração por agulha de punção, redução cirúrgica, esteroides sistêmicos, Sildenafil, administração intralesional de agentes esclerosantes, e radioterapia local. Relato de Caso No presente relato, descrevemos um caso incomum de linfangioma em uma paciente feminina de seis anos de idade, inicialmente submetida a procedimento neurocirúrgica para ressecção tumoral, com posterior terapia com Sildenafil, apresentando resultados promissores. Conclusão O tratamento de linfangiomas de órbita permanece um tópico controverso, e o uso de Sildenafil em conjunto com aspiração por agulha de punção e ressecção microcirúrgica é uma opção viável de tratamento. Entretanto, muitas quesitos tais como tempo de terapia, regime de dose e taxa de recorrência permanecem incertos. Nosso relato de caso contribui com dados promissores referente a esta patologia, ainda que ensaios maiores são necessários para elucidação apropriada acerca das questões pendentes.

Ganglioglial differentiation in a medulloblastoma with extensive nodularity / Diferenciação ganglioglial em um meduloblastoma com extensa nodularidade

We report the case of a 2 month-old patient with a large, probably congenital, posterior fossa tumor. Hematoxylin and eosin staining (HE), reticulin and immunohistochemistry revealed a medulloblastoma with extensive nodularity, showing ganglioglial differentiation, high proliferative index in the primitive neuroectodermal tumor (PNET) area and low proliferative index in the ganglioglial maturation area. Ganglioglial differentiation is a rare event in medulloblastomas and its mechanism is still unknown. Previous surgery, radiation and chemotherapy may contribute to differentiation in astrocytic and nerve cells. In this case, however, the differentiation was already present in the first specimen, prior to any surgical or therapeutic procedure.

Paciente de dois meses de idade apresentando grande tumor, provavelmente congênito, de fossa posterior. As colorações de hematoxilina e eosina (HE), reticulina e imuno-histoquímica revelaram meduloblastoma com extensa nodularidade, exibindo diferenciação ganglioglial, alto índice proliferativo na região de tumor neuroectodérmico primitivo e baixo índice proliferativo na área de maturação ganglioglial. Diferenciação ganglioglial é um evento raro em meduloblastomas e seu mecanismo ainda é desconhecido. Cirurgia prévia, radiação e quimioterapia podem contribuir para diferenciação em células astrocitárias e nervosas. Neste caso, entretanto, a diferenciação já estava presente no primeiro espécime, antes de cirurgias prévias ou procedimentos terapêuticos.