Congresso Brasileiro de Neurocirurgia 2023

Accuracy of Porto Alegre’s Line in predict lenticulostriate arteries encasement in insular gliomas.

Marco Antônio Schlindwein Vaz¹, Rafaela Fernandes Gonçalves^1,2,3,4, Jander Moreira Monteiro^1,2, Samir Aler Bark^1,3, Viviane Buffon¹, Samuel Dobrowolski¹, Gustavo Rassier Isolan^1,2,3,4

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT) 

Purpose: The Insula is a common site of gliomas.  Such lesions are of challenging surgical management because of complex anatomy of the lobe and the proximity to functional structures such as basal ganglia, internal capsule, speech and language processing cortex and subcortex as well as arteries like the middle cerebral artery and lenticulostriates arteries (LSTa). Brain mapping is quite challenging when the medial aspect of insular tumors does not displace but involve the LSTa. In these cases, even intensive efforts to preserve the integrity of the internal capsule based on subcortical mapping, results in no assurance that the patient will not experience a new motor or sensorial deficit in the postoperative period. This is the main reason why studying the relation of the LSA with the medial aspect of the insular tumors preoperatively and intraoperatively is of paramount importance.

Methods: A retrospective review of our database of 52 patients of insular glioma operated on by the senior author (GRI) between 2007 and 2018 was performed. For patients of insular gliomas undergoing awake surgery, our medial limit of resection, mainly in the tumor part located next to the limen of insula, was identified primarily through altered speech patterns, such as paraphasia during electric subcortical stimulation of the inferior fronto-occipital fasciculus (IFOF). To evaluate the potential involvement of LSA within the medial aspect of the tumor, we carried out an accurate analysis of the coronal and axial T2 and T1-weighted MR images and considered that the tumors that entangled these vessels could not be entirely resect.

Results: Lenticulostriate arteries involvement was determined from preoperative and intra-operative findings, as described above. In 13 patients LSTa were founded to be involved by the tumor. In 3 patients there were no involvement of the LSTa  which has allowed a more aggressive resection. These findings may suggest that tumors with a medial putaminal invasion cannot be submitted to an almost complete resection without causing a serious neurological deficit. Most of these patients have a subtotal resection whatever approach is chosen (transsylvian or transcortical). Probably the LSTa involvement is the most important medial limiting factor to obtain a more aggressive tumor resection and a good overall survival as well (P=0.022).

Conclusion: We have found that LSTa encasement is limiting factor to reach a good EOR

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The rise and fall of Broca’s area

Marco Antônio Schlindwein Vaz¹, Rafaela Fernandes Gonçalves^1,2,3,4, Samuel Dobrowolsky¹, Jander Moreira Monteiro^1,2, Francisco Braga¹, Eberval Gadelha Figueiredo⁵, Gustavo Rassier Isolan^1,2,3,4

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Universidade de São Paulo (USP)

Introduction: Surgery of glial tumors in eloquent areas, including the region of language and speech, is still a major dilemma in neurooncology, especially regarding the objective of surgery to maximize the extent of resection while preserving or even improving brain functions. It is postulated that due to brain plasticity, some slow-growing tumors, such as low-grade gliomas located on or around language areas, functionally shift these areas to brain anatomical regions that classically are not correlated to Broca’s area or others classic language areas.

Patients and Methods: From a series of 81 patients with eloquent brain tumors operated on by the senior author between 2007 and 2020, 9 patients with glioma on the dominant hemisphere localized on or around Broca’s area were operated on using awake cortical and subcortical brain mapping. Only patients in which the classical Broca’s area was stimulated were considered in this study

Results: Tumor grade, extended of resection and location were studied. All tumors were located on the left hemisphere. After 6 months of surgery, no patient showed neurological deficit regarding language or somatosensorial.

Conclusions: The concept studied and proposed by the present article shows us that slow-growing tumors such as low-grade gliomas or high-grade glioma who started being low grade,  can be resected in eloquent areas of speech and language, with satisfactory recovery and absence of permanent functional deficits.

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Neurosurgical management of Skull base epidermoid tumors in children

Marco Antônio Schlindwein Vaz¹, Rafaela Fernandes Gonçalves^1,2,3,4, Joel Lavinsky^1,5, Ricardo Santos¹, Francisco Braga¹, Paola Santis Isolan⁶, Giuseppe Santis¹, Gustavo Rassier Isolan^1,2,3,4

 

¹ Department of neurosurgery. The Center for Advanced Neurology and Neurosurgery (CEANNE), Porto Alegre, Brazil.

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Department of neurotology, Clinica Lavinsky (The Center for Neurotology and acoustic neuroma – CNNA), Porto Alegre, Brazil.

⁶ Department of pediatric surgery, Rio Grande do Sul Federal University (UFRGS), Porto Alegre, Brazil.

Introduction: The epidermoid tumors (ET) are congenital and benign tumors that develop from de ectoderm during the neurogenesis. In the skull base, these lesions can insinuate themselves into several intracranial compartments by filling the subarachnoid space, and possible affecting some important structures, like the brainstem, cerebellopontine angle, the parapituitary in the middle fossa, and others. In the pediatrics skull base tumors, the ET represents 7-9%, being very rare. The surgical perspective of these cases is dependent on extension of the resection. We presented two cases of total and near total resection of epidermoid tumors in pediatric skull base, with successful outcomes.

Case 1: 9 years old boy, came to our clinic complaining of blurred vision. The cranial MRI showed a tumoral lesion in the suprasellar cistern. The patient was submitted to a right frontotemporal approach, transsylvian with tumor resection, improving visual symptoms and campimetry results. The pituitary stalk was encased by the tumor but could be preserved anatomically and functionally through meticulous dissection. A very small part of tumor-related adherent to the anterior choroidal artery was left behind and is being followed up in the last 8 years with a minimum increase in size. There was no postoperative deficit and the endocrinologic function was preserved.

Case 2: A 12-year-old girl came to the emergency department complaining of blurred vision and mild headache for 3 days. Eyes fundoscopy exam showed bilateral papillary edema. CT showed a hypodense tumoral image in the prepontine and cerebellopontine cisterns plus obstructive hydrocephalus. MRI axial T2-weighted image showed a cerebrospinal fluid intensity, extra-axial cystic lesion in the right CPA, and prepontine cisterna. The patient was operated on with intraoperative monitoring. A retrosigmoid approach was performed. The tumor was resected through the window between the lower cranial nerves and the VII/VIII nerves. There was no postoperative deficit. The patient was discharged one week after the first surgery. An MRI in the immediate postoperative and 3 months after surgery showed total resection.

Conclusion: The presented cases show the total and/or near-total resection of a skull base ET in the pediatric population.

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How medical students are interpreting the medical literature – a cross-sectional study.

Marco Antônio Schlindwein Vaz¹, Rafaela Fernandes Gonçalves^1,2,3,4 e Gustavo Rassier Isolan^1,2,3,4 

¹ Department of neurosurgery. The Center for Advanced Neurology and Neurosurgery (CEANNE), Porto Alegre, Brazil.

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

 

Introduction: The scientific articles have an important role in the learning-teaching process for all kind of professionals. However, the easy access to a specialize content and the large number of papers available about the same subject makes it hard the interpretations of information, especially for the academic population. In view of the problem, this paper aims to study the main difficulty in the choosing an interpreting the scientific literature.

Methodology: It was made questions about the way that the participants search for knowledge, in addition to queries apropos technical issues over the scientific literature interpretation. The interviewed answered in spontaneous way through social media, Instagram® and LinkedIn®, as online questionaries in Google Forms®. The data were collected anonymously and stratified in area of expertise and scholarity level, being the lowest accepted: higher education in course.

Results: 53% of the interviewed didn’t know the difference between grade of recommendation and level of evidence. 28% of the interviewed didn’t know what is bias in scientific research. Asked about the possible quantity of bias that scientific research can have, 49% answered “1”, 13% “>10”, 4% “>50” and 34% choose to the answer “it isn’t possible to determine precisely.” When asked about the main way used to search for knowledge, 18% answer “apps and specialized tools”, 25% “classes, and materials provide by the teachers”, 27% “textbooks” and 30% “scientific articles”. Lastly, we ask the main aspect that draws attention when they choose to read an entire article, 9% answer “renowned authors”, 19% “journals quality”, 22% “attractive title” and 50% answered “interesting abstract”.

Conclusion: In view of the large academic difficulty to interpret the literature and comprehend the scientific research concepts, the utilization of the proposed analytic method became crucial to a better understanding of the data and the conclusion bring by the science.

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Endolymphatic sac tumor – surgical Experience with 4 cases and review

 

Marco Antônio Schlindwein Vaz¹, Rafaela Fernandes Gonçalves^1,6, Jander Monteiro^1,6, Francisco Luiz Souza Braga¹, Joel Lavinsky², Giuseppe Casella Santis³, Leandro Infantini Dini⁴, Marcelo Assis Moro da Rocha Filho⁵, Carmen Austrália Paredes Marcondes Ribas⁶, Ricardo Marques Lopes de Araújo⁷, Eberval Gadelha Figueiredo⁷, Gustavo Rassier Isolan¹

¹ Neurosurgery. The Center for Advanced Neurology and Neurosurgery, Brazil (CEANNE)

² Otology and Otoneurology. The Center for advanced neurology and neurosurgery, Brazil (CEANNE)

³ Medicine. University of North Georgia (UNG)

⁴ Neurosurgery. Universidade Feevale (FEEVALE)

⁵ Otology and Otoneurology. Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA)

⁶ Medicine. Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁷ Neurosurgery. Faculdade de Medicina, Universidade de São Paulo (USP).

 

Objective: the authors focus on describing the endolymphatic sac tumor and present four illustrative cases.

Methods: Review previous studies from 1957 to 2021 from basic and translational research using human and animal ES tissue or cells, as well as previous reviews about the subject, using the terms individually and combined: Endolymphatic sac tumor, clinic, diagnosis, treatment, neurosurgery. We review the endolymphatic sac tumors and present 4 illustrative cases.

Results: The endolymphatic sac (ES) is a structure situated in the inner ear, and is responsible for homeostasis regulation of the internal ear, endolymphatic fluid volume, immune response, etc. One of the possible alterations of the ES is the endolymphatic sac tumor (ELST), a slow-growing, locally aggressive, low-grade malign neoplasm that originates from the epithelium of the endolymphatic duct and sac. The clinical presentation of the ELST includes hearing loss, tinnitus, headache, and vestibular dysfunction represented by vertigo. The diagnosis in the early stages is rare, given that this group of symptoms is very similar to other more common diseases like Menière’s disease. Its diagnosis is made by CT, MRI, immunohistochemistry, and confirmed by histopathology. However, none of these exams are in current guidelines addressing common pathologies that mimic ELST symptoms. The treatment for ELST in the early stages has a high rate of success.

Conclusion: The ELST is a very difficult diagnosis since its early stages present very similar to other more common diseases. Furthermore, the interaction of the ELST and Von Hippel-Lindau disease results in an even more complicated condition in all terms. Despite the difficulty of the diagnosis, doing it early increases the chances of successful treatment.

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Identification of CD114 Membrane Receptors as a Molecular Target in Medulloblastomas.

Marco Antônio Schlindwein Vaz¹, Jander Monteiro^1,2, Jaqueline Isadora Reis Ramos³, Ian Teixeira e Sousa³, Rayana Longo Bighetti-Trevisan¹, Rafaela Fernandes Gonçalves^1,2,3,4, Gustavo Rassier isolan ^1,2,3,4

¹ Department of neurosurgery. The Center for Advanced Neurology and Neurosurgery (CEANNE), Porto Alegre, Brazil.

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

 

Introduction: Medulloblastomas are the most common solid tumors in children, accounting for 8–30% of pediatric brain cancers. It is a high-grade tumor with aggressive behavior and a typically b poor prognosis. Its treatment includes surgery, chemotherapy, and radiotherapy, and presents high morbidity. Significant clinical, genetic, and prognostic differences exist between its four molecular subgroups: WNT, SHH, Group 3, and Group 4. Many studies seek to develop new chemotherapeutic agents for medulloblastomas through the identification of genes whose expressions are new molecular targets for drugs, such as membrane receptors associated with cell replication. This study aimed to assess the association of CD114 expression with mortality in patients with medulloblastoma.

Methodology: Databases from the Medulloblastoma Advanced Genomics International Consortium (MAGIC) were analyzed, focusing on the expression of the CD114 membrane receptor in different molecular types and its possible association with mortality.

Results: Our findings showed different CD114 expressions between Group 3 and other molecular groups, as well as between the molecular subtypes SHH γ and Group 3 α and Group 3 β. There was no statistically significant difference between the other groups and subtypes. Regarding mortality, this study did not find statistical significance in the association between low and high CD114 expressions and mortality.

Discussion: Medulloblastoma is a heterogeneous disease with many subtype variations of its genetic and intracellular signaling pathways. Similarly, to this study, which could not demonstrate different CD114 membrane receptor expression patterns between groups, others who sought to associate CD114 expression with mortality in other types of cancer failed to establish a direct association. Since many indications point to the relation of this gene with cancer stem cells (CSCs), it may be part of a more extensive cellular signaling pathway with an eventual association with tumor recurrence.

Conclusion: This study found no direct relationship between CD114 expression and mortality in patients with medulloblastoma. Further studies are needed on the intracellular signaling pathways associated with this receptor and its gene (the CSF3R).

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Instability of craniocervical junction caused by invasive pituitary prolactinoma and the “hook” effect.

Victor Olaves(1), Rafaela Gonçalves(1,2,3,4), Mario CArrion (1), Ricardo Santos (1), Francisco Braga (1) Joel Lavinsky (1), Bernard Soccol Beraldin(1), Gustavo Rassier  Isolan(1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

Case report: Increased serum prolactin is the main diagnostic criterion for prolactinoma in patients with sellar tumors and hyperprolactinemia symptoms. The Hook Effect can occur in a highly concentrated prolactin protein sample, increasing the chance of a false negative result. Craniocervical junction instability is a medical emergency and is rarely caused by pituitary adenomas.In this study, we present a case of a 43-year-old male patient who was admitted at our medical service due to important cervical pain and sensation of the head ‘’dropping’’, which makes necessary to hold it in order to decrease the pain. The patient complains about these symptoms for 2 weeks. Magnetic Resonance Imaging showed skull base voluminous tumor invading the anterior cranial fossa, clivus and sellar region totally; medium, pterygopalatine and infratentorial fossae bilaterally; cavernous sinuses and petrous Apex bilaterally. Except for the pain and signs of left glossopharyngeal palsy, there were not any other symptoms. Brain Computed Tomography evidenced bilateral erosion of the occipital condyles. Endocrinological evaluation was normal, but for discrete increase of serum prolactinThe patient underwent occipitocervical fixation and an extended endoscopic endonasal approach guided by neuronavigation, resulting in resection of all tumoral extensions from the anterior fossa to the clivus. In the postoperative period, the patient’s symptoms remitted, and he underwent dopamine agonist therapy. However, after two weeks of surgery, the prolactin level was greater than 1000 mcg/L, indicating the Hook Effect.

Conclusion: Invasive adenomas with high immunoreaction to prolactin can cause craniocervical junction instability, requiring prompt surgical intervention. The Hook Effect should be considered in patients with suspected prolactinoma, especially those with high prolactin levels, to prevent false negative results.

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Brain tumors, brain metastases, and neuroinflammation: Insights from neuroimaging studies

Haniel Bispo(1), Rafaela Gonçalves(1,2,3,4), Rafael Roesler (4), Simoi Dini (1), Leandro Dini (1), Gustavo Isolan(1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

Introduction: Brain tumors and brain metastases can cause changes in brain tissue remodeling that lead to immunosuppression and trigger an inflammatory response within the tumor microenvironment. These immune and inflammatory changes can influence invasion and metastasis. Additionally, neuroinflammatory and necrotic lesions may occur in patients with brain cancer or brain metastases as a result of treatment with radiotherapy.

Objective: This article aims to review recent advances in imaging methods that have helped improve the specificity of primary tumor diagnosis versus the evaluation of inflamed and necrotic brain lesions. We also comment on advances in differentiating metastasis from neuroinflammatory processes.

Methods: We conducted a literature review of recent studies on imaging methods for brain tumors, focusing on positron-emission tomography (PET) and magnetic resonance imaging (MRI) techniques. We analyzed the strengths and limitations of current imaging protocols and identified recent advances in imaging methods that have helped to differentiate between tumor tissue and inflammation.

Discussion: Differentiating between tumor tissue and inflamed brain tissue with imaging protocols remains a challenge. However, recent advances in imaging methods have helped improve the specificity of primary tumor diagnosis versus evaluation of inflamed and necrotic brain lesions. These include the radiosynthesis of 18F-FIMP, an L-type amino acid transporter 1 (LAT1)-specific PET probe, and the combination of different advanced imaging protocols with the inclusion of radiomics and machine learning algorithms.

Conclusion: Recent advances in imaging methods have shown promising results in improving the specificity of primary tumor diagnosis versus the evaluation of inflamed and necrotic brain lesions. These advances may have significant implications for the diagnosis and therapeutic evaluation of brain tumors, including the most aggressive primary malignant brain cancer in adults, glioblastoma (GBM). Further research is needed to determine the clinical utility of these new imaging methods and their potential impact on patient outcomes.

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Small Vestibular Schwannomas – a surgical disease

Haniel Bispo(1), Rafaela Gonçalves(1,2,3,4), Joel Lavinsky(1), Francisco Braga (1), Ricardo santos (1), Gustavo Gabellini (1), Henrique Leydner (1), Gustavo Rassier Isolan(1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

 

Introduction: Small vestibular are noncancerous tumors that develop on the nerve responsible for balance and hearing. These tumors are usually slow-growing and may cause any symptoms at first. Those tumors of small dimensions (Hannover 1,2 and 3) have a contradictory approach that can range from clinical observation, microsurgery or radiosurgery, with no international consensus on the best approach.

Objective: To show the absence of long-term morbidity and mortality in small schwannomas and why we selected microsurgery as the technique of choice for the management of these tumors.

Methods: From a series of 187 vestibular schwannomas treated surgically or under follow-up by the authors (Porto Alegre Skull Base Team), we selected surgical videos of the translabyrinthine and retrosigmoid approaches to discuss the step-by-step of the surgery and the precautions that the multidisciplinary team should take to avoid any sequelae.

Results: Based on the results of our study, the microsurgical technique for the management of small vestibular schwannomas showed an extremely satisfactory outcome, with no long-term morbidity or mortality observed in our patient population. The surgical videos of the translabyrinthine and retrosigmoid approaches allowed us to discuss the step-by-step of the surgery and the precautions that should be taken to avoid any sequelae. Therefore, we recommend microsurgery as the technique of choice for the management of small schwannomas.

Conclusion: Microsurgery is a safe and effective technique for the management of small vestibular schwannomas, with no long-term morbidity or mortality observed in our patients. The choice of approach should be based on the tumor size, location, and patient characteristics, and the surgical team should take precautions to minimize any potential sequelae. Further studies are needed to determine the optimal management approach for small vestibular schwannomas.

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 Facial nerve Hemangioma – a rare disease. 

Luiza Marques(1), Rafaela Gonçalves(1,2,3,4), Jander Monteiro (1)  Joel Lavinsky(1), Franisco Braga (1), Gustavo isolan(1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

Case Report: Facial nerve hemangiomas (FNH) are rare tumors corresponding to 0.7% of intratemporal tumors. Although they can occur in any portion of the nerve, the most frequent site is near the geniculate ganglion. We present a unique case of facial nerve hemangioma in the lateral portion of the right internal auditory canal. A 30-year-old female patient presented with severe hearing loss on the right side and progressive facial paralysis. Magnetic resonance imaging revealed a 5 mm lesion in the lateral portion of the right internal auditory canal, raising suspicion of a possible diagnosis of facial nerve hemangioma. Due to facial paralysis, the approach chosen was translabyrinthine, and total tumor resection was performed, followed by anastomosis of the hypoglossal-facial nerve.

Discussion: The facial nerve is susceptible to expansive lesions with high morbidity, and the symptoms may vary depending on the type and location of the tumor. FNH is a rare lesion that is difficult to diagnose. When it occurs in the internal auditory canal, 70% of cases present with paralysis, and 90% have hearing loss, as in our patient. Computed tomography and magnetic resonance imaging can be used to diagnose the condition. Differential diagnosis of FNH includes schwannomas, meningiomas, cholesteatomas, paragangliomas, and other temporal bone tumors. There is no established consensus on the best approach. Some studies suggest conservative treatment and serial imaging tests due to its benign character and slow growth.

Conclusion: Facial nerve hemangiomas (FNHs) may be small, but they can cause significant symptoms and have a high risk of complications. Early diagnosis is crucial, and surgical treatment is often necessary for a curative outcome. Therefore, surgery is considered the mainstay of treatment for FNHs due to their high morbidity.

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Maffucci’s Syndrome complicated by Skull Base Chondrosarcoma – our experience with 4 cases

Haniel Bispo(1), Rafaela Gonçalves(1,2,3,4), Ricardo santos (1), Leandro Dini (1), Gustavo Rassier Isolan(1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

 

Introduction: Maffucci syndrome is a rare congenital disease caused by somatic mutations of isocitrate dehydrogenase 1 (IDH1) and IDH2, characterized by the occurrence of multiple enchondromas, soft tissue hemangiomas, and phlebectasia, which can progress to chondrosarcomas or hemangiosarcomas. In this review, we report four cases of male patients with Maffucci syndrome who were referred to our department after diagnosis of an intracranial lesion at the skull base.

Results: We operated on four patients with Maffucci syndrome complicates by condhrosarcoma. Multiple skull base approaches were used and treatment was completed with radiosurgery.

Discussion: Currently, there is no definitive treatment for enchondromatosis in general, and Maffucci syndrome in particular. The best treatment for patients with chondrosarcoma of the skull base is total resection followed by radiotherapy. However, the feasibility of complete resection is often limited by various factors, such as tumor location, size, and vascular invasion.

Conclusion: A complicated case of Maffucci Syndrome involving chondrosarcomas at the base of the skull presents a difficult challenge, which requires a multidisciplinary team with expertise in skull base surgery and experience in various surgical approaches for chondrosarcoma removal. Due to the potential involvement of cranial nerves, intraoperative neurophysiological monitoring is crucial.  

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Transtemporal Approaches: from the microsurgical laboratory to the operative theater

Haniel Bispo(1), Rafaela Gonçalves(1,2,3,4), Felipe Salvagni Pereira, (1,5) Amylcar Edemilson Dvilevicius (5), Ricardo Marques Lopes de Araújo (1), Joel Lavinsky(1), José Polansky (3) , Samir Ale Bark (1,3) Gustavo Rassier Isolan(1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

5 – Hospital Angelina Caron – Paraná

Introduction: The temporal bone is one of the main avenues for deep access to the skull base. The success of these approaches depends on exhaustive study of temporal bone in microsurgical laboratory.

Objective: review of the temporal bone and the main surgical approaches in the region, from laboratory to operating room.

Methods: Fifteen temporal bones and twenty heads were dissected at the laboratories of Beneficência Portuguesa de São Paulo, Dianne and Gazy Yasargil Microsurgical Laboratory, in Arkansas, and laboratory of anatomy at UFRGS. Surgical cases were operated on by the authors.

Results: The temporal bone can be divided into five parts. Each portion has numerous relationships with nervous, vascular structure and muscular insertions. Understanding these relationships is a prerequisite for approaching the skull base. We used the dissected pieces to illustrate cases of real patients for the approaches: Anterior Petrosectomy, Translabyrinthine, Presigmoid, Retrosigmoid, Subtemporal Preauricular for infratemporal fossa and Postauricular transtemporal.

Conclusion: Mastering of temporal bone anatomy learned in the laboratory is essential for the treatment of primary lesions in the region, as well as for complex surgical approaches to the skull base.

Keywords: Temporal bone; Skull base; Neuroanatomy

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Hannover IV vestibular schwannoma – Technical nuances to achieve total or near total resection with no facial paralysis

Haniel Bispo(1), Rafaela Gonçalves(1,2,3,4), Joel lavinsky(1), Francisco Braga (1), Ricardo santos,(1) Gustavo gabellini (1), Henrique laydner (1),  Gustavo Rassier Isolan(1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

Introduction: Large vestibular schwannomas are complex and challenging tumors that require careful treatment. The Hannover classification divides these tumors into four grades, with grade IV tumors being the largest and most difficult to treat. The best treatment for these tumors is total or near-total resection, which is performed using microsurgery, despite an emerging misconcept that suggests the possibility of performing a subtotal or partial resection of the tumor followed by radiosurgery.

Objective: Highlight the technical nuances involved in the possibility of performing a total or near-total resection of the tumor, while preserving the function of the facial nerve.

Methods: We selected surgical videos of the retrosigmoid approach for large tumors, discussing the step-by-step procedure and necessary precautions to avoid any sequelae, from a series of 187 surgically treated vestibular schwannomas by our team (Porto Alegre Skull Base Team) or being followed up by the authors.

Results: The retrosigmoid craniotomy allows for a panoramic view for the removal of giant vestibular schwannomas or the option of hearing preservation with small, favorable medial tumors.

Conclusion: By following the step-by-step of the retrosigmoid approach, it is possible to perform total or near resection of the tumor, preserve hearing and reduce long-term complications of the facial nerve.

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Temporal bone microsurgical lab training guided by temporal bone CT Scan – a novel way for correlation surgery and neuroimage.

Haniel Bispo(1), Rafaela Fernandes Gonçalves(1,2,3,4), Diego Sgarabotto Ribeiro (5), Geraldo Pereira, Jotz (5) Natália Cândido de Sousa (5), Enio Tadashi Setogutti (7),  Marco Antonio Stefani (5), Ricardo Ferreira Bento (6), Joel Lavinsky(1,5), Gustavo Rassier Isolan (1,2,3,4)

1 – Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

2 – Spalt Therapeutics

3 – Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

4 – National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

5 – UFRGS

6.- USP

7 – SIDI Imagem

Introduction: Temporal bone anatomy is complex and demands a profound anatomical knowledge. Association between surgery and imaging helps in the process of learning three-dimensional (3D) anatomy and surgical techniques. High definition temporal bone imaging can play an important role in dissection training.

Objective: To describe a computed tomography (CT) image-guided temporal bone dissection course for surgical training in otolaryngology and to verify the satisfaction level of the students with the course.

Methods: Descriptive research. The course took place at a research laboratory, with three experienced temporal bone surgeons. The participants were 12 otolaryngology residents. The laboratory has 7 modern workstations with microscope and monitors linked with a computerized video system. Cadaveric temporal bones were donated to the university. Imaging acquisition of the cadaveric temporal bones used in the course was performed in a multislice CT scanner. The CT images of cadaveric temporal bones were available with real-time access on the laboratory monitor’s screens during dissections.

Results: A total of 13 temporal bones were included for dissection. Students had the opportunity to view on the same screen, simultaneously, both the dissection video and the respective CT images of their temporal bone anatomical specimens. This allowed correlating surgical and imaging aspects of temporal bone anatomy. At the end of the course, participants answered a satisfaction survey.

Conclusion: Considering imaging methods are routinely used during most otologic surgeries, detailed knowledge of CT imaging should be explored in conjunction with the temporal bone anatomical dissection.

Keywords: Temporal bone; dissection; anatomy; computed tomography

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Towards Precision Medicine for Meningioma: Exploring Receptor Tyrosine Kinases as Prognostic Biomarkers and Therapeutic Targets.

Victor Mascarenhas^1,2, Davi Orli Machado Grüdtner^1,2, Rafaela Fernandes Gonçalves^2,3,4,5, Rafael Roesler ^5,6,7, Barbara Kunzler Souza^5,6,8, Gustavo Rassier Isolan^2,3,4,5

¹ Universidade Federal de Santa Catarina (UFSC)
² Centro Avançado de Neurologia e Neurocirurgia (CEANNE)
³ Spalt Therapeutics
⁴ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)
⁵ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)
⁶ Cancer and Neurobiology Laboratory, Experimental Research Center, Clinical Hospital (CPE-HCPA), Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
⁷ Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
⁸ Epigenica Biosciences, Canoas 92035-000, Brazil Epigenica Biosciences, Canoas, RS, Brazil.

Introduction: MGMs are the most common intracranial primary tumors in adults. These lesions can be grouped into three grades and further divided into 15 subtypes. In addition to the contribution of PET imaging, MRI, and histopathological analysis, other classification methods based on biomarkers have been proposed. The biology of MGMs shows parallels between meningeal embryology and oncogenesis. The standard treatment is total surgical resection, which is replaced by radiotherapy in grade III tumors.
Methods: Selection of experimental and clinical studies that presented evidence of RTKs as therapeutic targets or biomarkers in MGM. Experimental models with MGM tumor specimens and cultured cells were analyzed, as well as patients with MGM, hemangiopericytoma, hemangioblastoma, or radiographic characteristics of surgically inaccessible and recurrent MGM. Most studies included immunohistochemical analyses, tissue microarrays, and next-generation sequencing to identify the expression and activation of EGFR, HER2, HER3, and HER4, among other proteins.
Results: Evidence suggests that RTK inhibitors can reduce cell proliferation and increase progression-free survival in patients. Furthermore, the differential expression of EGFR can serve as a biomarker to distinguish anaplastic meningiomas from hemangiopericytomas, whereas the high expression of EGFR and PDGFR is associated with worse prognoses in MGMs, as it is linked to an increased tumor recurrence and reduced patient survival.
Conclusion: To date, there are no clinically effective molecularly targeted therapies to treat patients with aggressive MGMs. Although accurate biomarkers have not been discovered yet, findings show that RTKs, especially EGFR and other members of the ErbB family, should be further investigated as biomarkers capable of early detection of the grade and prognosis of surgically removed MGMs.

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Multiple foramen jugular and carotid body paraganglioma treated with total microsurgical resection

Luiz Henrique Perszel¹, Marco Antônio Schlindwein Vaz¹, Rafaela Fernandes Gonçalves^1,2,3,4, Joel Lavinsky^1,5, Francisco Braga¹, Gustavo Maia Gabellini,  Ciro Weiss Fontana (6),  Gustavo Rassier Isolan^1,2,3,4

¹ Department of neurosurgery. The Center for Advanced Neurology and Neurosurgery (CEANNE), Porto Alegre, Brazil.

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Department of neurotology, Clinica Lavinsky (The Center for Neurotology and acoustic neuroma – CNNA), Porto Alegre, Brazil.

6 – Santa Casa de Porto Alegre

Introduction: Paragangliomas are slow-growing neoplasms, mostly benign, but can present malignant behavior in 10%-20% of cases. Paragangliomas arise along the parasympathetic nervous system in relation to the neurovascular bundle. The occurrence of this lesion in the base of the skull (BC) is rare, accounting for 0.6% of all head and neck neoplasms. Its presence in a structure like the jugular foramen results in a highly vascularized tumor with the potential to affect adjacent structures such as cranial nerves IX, X, and XI, as well as eventually the inferior petrosal sinus, becoming a surgical challenge. This paper aims to demonstrate a successful experience in the surgical management of multiple paragangliomas, a very rare condition.

Case : A 47-year-old woman presented to our neurology clinic with a history of mild hoarseness and cervical pain for 3 weeks. On physical examination, there were no focal neurological signs or paralysis of cranial nerves, but there was a hard and palpable mass in the left cervical region. MRI of the skull and cervical region revealed a small tumor at the right carotid bifurcation and a tumor at the right jugular foramen with signs of flow-void inside, as well as a voluminous tumor in the left carotid body topography. There were no signs of instability of the craniocervical junction. AngioMRI showed highly vascularized lesions, establishing a presumptive diagnosis of multiple paragangliomas. Urinary vanillylmandelic acid levels were negative, and the patient underwent embolization of the jugular foramen tumor and resection of the right jugular foramen paraganglioma and ipsilateral carotid body tumor. After 2 months, the patient underwent a new surgery for total resection of the left cervical paraganglioma. There were no deficits in both procedures.

Discussion:

The present case report demonstrates a successful surgical management of a patient with multiple paragangliomas, highlighting the challenge of approaching a highly vascularized tumor located in the right jugular foramen.

Paragangliomas are rare tumors, accounting for less than 0.1% of all human neoplasms. They arise along the parasympathetic nervous system in relation to the neurovascular bundle and can occur in various locations, such as the head and neck, chest, abdomen, and pelvis. Although most paragangliomas are benign, they have the potential to become malignant in approximately 10% to 20% of cases, making early diagnosis and treatment essential.

In this case, the patient presented with nonspecific symptoms, such as mild hoarseness and cervical pain, which led to the discovery of palpable masses in the cervical region and imaging exams confirming the diagnosis of multiple paragangliomas. The presence of highly vascularized lesions, confirmed by angioMRI, and the location of one of the tumors in the right jugular foramen represented a significant surgical challenge. The treatment of choice for paragangliomas is complete surgical resection of the lesion. In the present case, embolization of the jugular foramen tumor allowed for safe resection of the lesion and preservation of adjacent cranial nerve function.

Conclusion: This case highlights the importance of early diagnosis and multidisciplinary approach in the management of multiple paragangliomas. Preoperative embolization can be a useful option to reduce the risk of intraoperative bleeding in highly vascularized tumors, such as jugular foramen paraganglioma, and complete resection of the lesion is the treatment of choice to prevent recurrence and potential malignancy.

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INSULA GLIOMAS: CORRELATION BETWEEN THE TYPE OF APPROACH (TRANSYLVIAN X TRANSCORTICAL) WITH EXTENT OF RESECTION, MORBIDITY AND SURVIVAL

Luiz Henrique Perszel¹, Marco Antônio Schlindwein Vaz¹, Viviane Buffon¹, Samir Aler Bark^1,3, Rafaela Fernandes Gonçalves^1,2,3,4, Gustavo Rassier Isolan^1,2,3,4

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

Introduction: Insular tumors are responsible for up to 25% of low-grade gliomas and 10% of high-grade gliomas. The insula has a complex anatomy, including an eloquent cortex and intimate contact with a vascularization responsible for the arterial supply to the motor and language systems. The choice of transsylvian or transcortical corridors for resection of insular gliomas remains controversial, and the main concerns are vascular injury during transsylvian dissection and functional impairment in transcortical access. The aim of this study is to compare whether there is a difference between the extent of lesion resection, postoperative morbidity and survival between the two approaches.

Patients and Method: 55 patients who underwent resection of insular gliomas were evaluated by data related to sex, age at the date of the surgical procedure, presence of refractory epilepsy in the preoperative period, side of the lesion, the volume of the lesion in cm3, were calculated from preoperative brain MRI, classification of island tumors, the surgical technique used, intraoperative monitoring, histological grade obtained through anatomopathological examination, extension of surgical resection in the postoperative period, neurological examination in the preoperative period, late postoperative period , evaluated in 6 months, in addition to the evolutionary follow-up until December 2020.

Results: Data from 55 patients with low or high-grade island gliomas were analyzed. Thirty-one patients (56.4%) were submitted a transsylvian approach, and 28 patients (43.6%) under a transcortical approach. The resection extension (ROS)> 90% was 61.3% in the transsylvian group and 45.8% in the transcortical group (p = 0.385). The late postoperative evaluation for the 2 groups was similar. Overall, 8 patients (25.8%) in the transsylvian group and 5 patients (20.8%) in the transcortical group had persistent neurological deficit in the late postoperative period. The 24-month survival rate were present in 81.3% of the transcortical group and 92% in the transcortical group.

Conclusions: The transsylvian and transcortical approach do not present any significant difference in relation to the degree of resection (P = 0.385), in survival (P = 0.204) and in the presence of deficit in the late postoperative period. Thus, the chosen approach should be individualized and the surgical team experience taken into account.

Key Words: Insula gliomas. Brain mapping. Transsylvian.Transcortical. Extent of resection. Surgical techique.

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Aspergilosis mimicking Skull Base Tumor 

Luiz Henrique Perszel¹, Haniel Bispo de Souza Maranhão¹, Rafaela Fernandes Gonçalves^1,2,3,4, Mario carrion, (1)  bernard beraldin, (1)  Gustavo Rassier Isolan^1,2,3,4

¹ Department of neurosurgery. The Center for Advanced Neurology and Neurosurgery (CEANNE), Porto Alegre, Brazil.

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

Introduction: Aspergillosis is an infection caused by the fungus Aspergillus. The fungus Aspergillus exhibits an affinity for pulmonary arterioles, which may result in ischemic necrosis of these structures. In addition, in rare cases, Aspergillus can disseminate through the bloodstream, exhibiting invasive and deleterious behavior towards other structures of the body, including the central nervous system (CNS). 

Case report: A 58-year-old male patient was admitted to our hospital with clinical symptoms of neuropathic pain in the right trigeminal nerve territory and decreased right visual acuity, without a previous history of illness. Magnetic resonance imaging (MRI) showed expansion in the nasal cavity involving the sphenoid sinus and bilateral hypopharynx. There was involvement of the orbit, cavernous sinus, pterygopalatine fossa, and infratemporal fossa on the right, with hyperintensity of the pterygoid muscles, suggesting subacute denervation of these muscles. There was also presence of edema in the straight gyrus of the right frontal lobe. With suspicion of carcinoma, endoscopic endonasal biopsy with intraoperative freezing was planned. After histopathological analysis, it was defined as a fungal lesion caused by Aspergillus. Based on this intraoperative finding, a wide resection of the orbital component, pterygopalatine fossa, and sphenoid of the lesion was performed.

There was no worsening of neurological symptoms in the postoperative period, and intravenous antifungal treatment was initiated. However, after 14 days, the patient presented neurological deterioration, and a new MRI showed an increase in the lesion and multiple tumors in the basal ganglia, as well as lung lesions. The patient died the next  week.

Conclusion: The authors discuss a rare case of Aspergillosis mimicking skull base tumor. They analyze current studies on Aspergillosis and its invasion of the CNS, discussing the fungus’s behavior, pathophysiology of the disease, as well as its clinical and therapeutic implications. Thus, they analyze the treatment used in the case, discussing its theoretical basis, impact, and established therapeutic pathways.

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Transmastoid Retrolabyrinthine Approach: An Alternative Pathway To Deal With Vestibular Schwannomas

Davi Orli Machado Grüdtner^1,2, Victor Mascarenhas^1,2, Rafaela Fernandes Gonçalves^2,3,4,5, Joel LAvinsky (2,6), Ricardo Santos (2), Francisco Braga (2) , Gustavo Rassier Isolan^2,3,4,5

¹ Universidade Federal de Santa Catarina (UFSC)
² Centro Avançado de Neurologia e Neurocirurgia (CEANNE)
³ Spalt Therapeutics
⁴ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)
⁵ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)
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Introduction: In the translabyrinthine approach for vestibular schwannomas, the auditory tube is closed in order to prevent cerebrospinal fluid leakage, and this procedure is indicated for patients who already have hearing loss. The transmastoid retrolabyrinthine approach is a variation of the translabyrinthine approach that avoids damage to the semicircular canals and ensures hearing preservation.

Patients and Methods: The Porto Alegre Skull Base Team followed a series of 187 patients with vestibular schwannomas, most of whom underwent surgical treatment. Among these cases, a surgical video was recorded demonstrating the transmastoid retrolabyrinthine approach.

Discussion: As modern diagnostic methods improve, smaller vestibular schwannomas can be detected earlier, even before the appearance of significant clinical signs and symptoms. Surgical techniques that preserve the functionality of the acoustic and facial nerves offer a new perspective on postoperative quality of life. The transmastoid retrolabyrinthine approach is useful for small tumors that reach the internal acoustic meatus but do not lead to hearing loss, having also the advantage of causing minimal cerebellar retraction.

Conclusion: The present article proposes the advantages of the transmastoid retrolabyrinthine approach over the translabyrinthine approach for patients with limited involvement of the acoustic nerve.

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BRACHIAL PLEXUS PALSY IN NEONATES: AN 2023 UP-TO-DATE

Poliana Zago Perondi^1,5, Rafaela Fernandes Gonçalves^1,2,3,4, Gustavo Rassier Isolan^1,2,3,4.

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Universidade Regional Integrada do Alto Uruguai (URI)

INTRODUCTION: Obstetric brachial plexus palsy (OBPP) is a brachial plexus injury resulting from maneuvers performed during a difficult birth. Although there is a high rate of spontaneous recovery within the first 6 months of life, functional deficits may persist, resulting in muscle weakness, limited range of motion, and limb discrepancy. However, surgery has a positive outcome, as infant nerves have greater regeneration and the distance for axons to reach the final organ is shorter.

OBJECTIVE: The present study aims to compile academic works on brachial plexus palsy in neonates in order to expand knowledge on the topic.

METHOD: A theoretical research was carried out on the LILACS, UpToDate, PubMed, Scielo, BIREME platforms, with reference to works produced in the last five years and filter applied for Portuguese, English, and Spanish language.

RESULTS: OBPP is defined as a brachial plexus injury resulting from maneuvers performed during a difficult birth. The brachial plexus (BP), formed by the anterior branches of spinal nerves from C5 to T1, has sensory and motor nerve roots to innervate the upper limb. Due to its location, lack of bony or muscular protection, and proximity to the neck and shoulder, the BP becomes susceptible to trauma. Most cases are due to excessive traction during birth, occurring in up to 15% of newborns with shoulder dystocia. However, OBPP is not necessarily associated with shoulder dystocia and can be congenital, intrauterine, or caused by endogenous forces. There are also external and internal factors related to OBPP, such as macrosomia, babies weighing above the gestational age, hypoxia at birth, gestational diabetes, and forceps or vacuum-assisted delivery. They are classified according to severity: injury to the upper trunk (C5 – C6 and sometimes C7) called Erb-Duchenne palsy, and those affecting the lower trunk (C8 – T1): Klumpke’s palsy. CONCLUSION: Brachial plexus palsy in neonates denotes a brachial plexus nerve injury in which the newborn’s shoulder gets stuck behind the mother’s pubic bone, and traction during birth results in injury. Thus, it poses a risk to the quality of life of neonates and, despite advances in medicine, remains incident in the population. However, increased awareness of shoulder dystocia and assisted delivery has reduced injuries. Therefore, OBPP negatively impacts all aspects of a child’s life and it is essential to understand the risk factors to prevent its occurrence. KEYWORDS: Obstetric palsy. Brachial plexus. Injury. Neonates. Maneuvers.

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DIFFUSE AXONAL INJURY – AN 2023 UP-TO-DATE

 

Luiz Henrique Perszel^1,5, Gustavo de Moraes Tedesco^1,5, Rafaela Fernandes Gonçalves^1,2,3,4, Gustavo Rassier Isolan^1,2,3,4

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Universidade Regional Integrada do Alto Uruguai (URI)

Introduction: Diffuse axonal injury (DAI) is a condition in which there is damage to neuronal axons. To understand the mechanism of injury, a difference in density is observed between the portions of black and white matter. This difference in composition and density leads to a sliding translocation between them in cases of sudden deceleration of the brain. This study aims to demonstrate a case of DAI in a young patient, contributing to the understanding of the injury, its impact, and related prognosis.

Case Presentation: An 18-year-old white male student with no underlying medical conditions and no continuous medication use was the victim of a high-kinetic car accident involving a school van and a pickup truck. He was admitted to the hospital with a Glasgow Coma Scale (GCS) score of 6, and DAI was observed on a CT scan of the skull. He was sedated and given supportive measures in the ICU. He remained in the ICU for 30 days and was discharged with a minimal state of consciousness, preserving vital functions such as circadian cycle, spontaneous breathing, and thermoregulation.

Discussion: Both DAI and the deposition of TAU protein and Wallerian degeneration are directly related to traumatic brain injury (TBI). Today, the study method to identify these injuries is diffusion tensor imaging (DTI), a method that represents axonal bundles in their biophysics as well as myelin sheaths, using the fractional anisotropy (FA) method. In TBI patients, a consistent reduction in FA was typically found in areas affected by traumatic axonal injury. Associated with trauma and axonal injury, the deposition of TAU protein and Wallerian degeneration are observed. The latter refers to the degeneration of the neuron after its axonal rupture, occurring in the most cranial region of the lesion, and is an aspect of a worse prognosis. The human brain presents an evolutionary landmark stemming from the ability to increase nutrient intake with less effort. This revolution marked the emergence of the cerebral cortex, responsible for functions such as speech and critical thinking. Therefore, the most basic level of consciousness, present in other mammals, responsible for circadian cycle, thermoregulation, and peripheral autonomic system, emerged before the aforementioned revolution, with such functions located in the brainstem and mesencephalon, where the ascending reticular activating system (ARAS) is located. When lesions are present in these locations, a direct impact on vegetative homeostasis and patient survival is observed.

Final Comments: This study reported a case of diffuse axonal injury, highlighting the mechanism of axonal shearing, followed by an analysis of the deposition of TAU protein and Wallerian degeneration. Finally, the primitive formation of the central nervous system (CNS) and the ARAS were discussed. Thus, the study presented an analysis of the pathophysiology and impact of the injury on the patient, as well as a prognosis for the clinical case. Keywords: Diffuse Axonal Injury; TBI; Wallerian Degeneration; ARAS; TAU Protein.

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Arachnoid cyst  – AN 2023 UP-TO-DATE

Gustavo de Moraes Tedesco^1,5, Rafaela Fernandes Gonçalves^1,2,3,4, Gustavo Rassier Isolan^1,2,3,4

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Universidade Regional Integrada do Alto Uruguai (URI) 

Case Report: A 15-year-old male patient presented to an otolaryngologist with complaints of nocturnal mouth breathing. A CT scan of the facial bones was requested to investigate for nasal septum deviation, which resulted in suspicion of an arachnoid cyst. Subsequently, an MRI revealed a giant arachnoid cyst of approximately 8 cm in the anterior region of the left hemisphere of the brain, causing midline shift. The patient underwent open neurosurgery, including craniotomy and communication of the cyst with the perimesencephalic cistern. The patient was followed up as an outpatient and remained stable.

Discussion: Arachnoid cysts are collections of cerebrospinal fluid that may progressively grow. The formation of an arachnoid cyst still represents an enigma in neuroscience. However, some mechanisms have already been established in the literature. The first mechanism involves unidirectional slit valves, resulting in the accumulation of cerebrospinal fluid in specific points of the central nervous system. The walls of some cysts may contain choroid plexus, contributing to the production of cerebrospinal fluid within the cyst itself. The second mechanism involves trauma, where there is injury and poor dynamic stabilization of cerebrospinal fluid circulation. The first mechanism is the one that best explains the presence of congenital cysts. The cysts have a predilection for certain points of the central nervous system, highlighting the middle fossa and Sylvian fissure. MRI is considered the gold standard for diagnosis. Arachnoid cysts are often described as purely accidental findings, and the vast majority of them are asymptomatic. There are case reports indicating a potential pathogenicity of the cyst, especially if located in the middle fossa of the skull, with subtle symptoms of learning, memory, attention, personality, and other psychiatric disorders, such as depression and anxiety. The optimal treatment for arachnoid cysts remains controversial, and the most appropriate approach is determined by the location and size of the cysts. The available options for managing arachnoid cysts are shunting procedures, craniotomy, stereotactic aspiration or fenestration of the cyst cavity, and neuroendoscopic fenestration.

Final Comments: This study reported a case of a congenital giant arachnoid cyst, which was incidentally discovered. The vast majority of cysts are asymptomatic, and there is a higher incidence in males, making the patient in this study an exemplar of the literature on arachnoid cysts.

Keywords: intracranial arachnoid cyst; asymptomatic; congenital. 

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SPONDYLODISCITIS: SURGICAL APPROACH UP TO DATE 2023 

Paolla Favaro Bressiani^1,5, Poliana Zago Perondi^1,5, Rafaela Fernandes Gonçalves^1,2,3,4, Gustavo Rassier Isolan^1,2,3,4

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Universidade Regional Integrada do Alto Uruguai (URI)

INTRODUCTION: Spondylodiscitis is a pathology occasionally found in neurosurgery wards caused by microorganisms such as bacteria, fungi, or parasites that affect one or more spinal structures such as vertebrae and intervertebral discs. Due to its nonspecific symptoms, the diagnosis tends to be slow and the disease is associated with a high mortality and morbidity rate.

OBJECTIVE: The present study aims to compile academic works on spondylodiscitis to expand knowledge about the subject.

METHOD: A theoretical search was conducted on the LILACS, UpToDate, PubMed, Scielo, and BIREME platforms, with a reference to works produced in the last five years and filters applied for Portuguese, English, and Spanish languages.

RESULTS: Spondylodiscitis is characterized by an infectious process of the vertebral discs and the vertebrae themselves, occurring due to mainly pyogenic dissemination. This is a disease that represents 5% of all osteoarticular infections, with an incidence of 0.5 to 2.5 per 10,000 inhabitants. This propagation process can occur hematogenously, where there is another site of infection in the patient in 62% of cases, by inoculation or contiguity. The clinical picture of the disease is characterized by acute or subacute low back pain, as well as fever and neurological deficit. Most of these patients are male, in the age range of 50-60 years, and the most common site of involvement is the L5 and S1 vertebrae levels. The most effective treatment is antibiotic therapy. For this, bacterial diagnosis is essential, which can be obtained through blood culture or biopsy. It should be noted that in 20 to 35% of cases, it is not possible to identify the microorganism responsible for the infectious picture, requiring the use of empirical treatment with broad-spectrum antibiotics. In surgery, a laminectomy is performed with decompression of the nerve roots and dural sac. Subsequently, debridement of the purulent collections in the paraspinal and epidural space is performed, as well as collection of material for culture. In addition, posterior transpedicular fixation with titanium screws and rods is performed. Surgical drains are left in the postoperative period to facilitate washing with antibiotics, according to the obtained culture result.

CONCLUSION: As mentioned above, the surgical approach to spondylodiscitis is adjuvant regarding the patient’s treatment, except in cases of sepsis, neurological deficit, spinal deformity, epidural empyema, and abscess. Antibiotic therapy plays a leading role in cases, which is specific or broad-spectrum, but only until the course of therapy is stable or progressive. Sequentially, the actual surgical treatment is preceded by radiological examinations and persistence of antibiotic therapy according to the case’s stability and occurs according to the pathological stage analysis, becoming genuine prior diagnostic guidance in both approaches agreed with the patient.

KEYWORDS: Spondylodiscitis. Neurosurgery. Antibiotic therapy. Infection. Sepsis.

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THE ROLE OF TRANSCRANIAL MAGNETIC STIMULATION IN NEUROLOGICAL PATHOLOGIES

UP TO DATE 2023

Camila Caetano Solek^1,5, Rafaela Fernandes Gonçalves^1,2,3,4, Gustavo Rassier Isolan^1,2,3,4

¹ Centro Avançado de Neurologia e Neurocirurgia (CEANNE)

² Spalt Therapeutics

³ Faculdade Evangélica Mackenzie do Paraná (FEMPAR)

⁴ National Science and Technology Institute for Children’s Cancer Biology and Pediatric Oncology – INCT BioOncoPed, Brazil (INCT)

⁵ Universidade Regional Integrada do Alto Uruguai (URI)

Introduction: Transcranial magnetic stimulation is a non-invasive technique capable of generating new action potentials in cortical neurons. From this perspective, it has shown promise in the treatment and diagnosis of brain pathologies such as traumatic brain injury, Parkinson’s disease, depression, and cerebral palsy.

Objective: This research aims to contribute to the knowledge of the scientific community and the academic authors through a comprehensive literature review, facilitating the research, study, and consultation of those interested in transcranial magnetic stimulation.

Method: A qualitative theoretical research was conducted, resulting in the present article. The LILACS, UpToDate, PubMed, Scielo, and BIREME platforms were used, with reference to works produced between 2018 and 2022 and a filter applied for Portuguese, English, and Spanish languages.

Results: Since its discovery, transcranial magnetic stimulation has been improved to generate different pulses and patterns, to the point of being able to treat various pathologies. As a benefit, it stimulates neuroplasticity and reduces sequelae resulting from the underlying pathology. Therefore, transcranial magnetic stimulation can act as an alternative approach to treating diseases in the psychiatry and neurology fields. With this focus, it has played a major role in managing multiple sclerosis, allowing for the evaluation of the progression of chronic autoimmune demyelinating pathology, as well as the effectiveness of drugs used.

Furthermore, it may also be indicated for the treatment of severe depressive disorder. It has also been studied to treat or diagnose other diseases such as Alzheimer’s disease and in the treatment of complications resulting from cerebral infarction, by promoting neuroplasticity. However, the most well-established clinical use is in the treatment of medication-resistant depression.

Conclusion: As mentioned above, transcranial magnetic stimulation has proven effective in mental and psychological disorders, as well as demyelinating and degenerative diseases such as multiple sclerosis and Alzheimer’s disease, respectively. Its probable effectiveness in cases of cerebral infarction by promoting neuroplasticity has also been corroborated. However, it is necessary to encourage research on this technique to promote better health outcomes in the aforementioned cases.