Defining the limits of the anterior wall of the cavernous sinus through an endoscopic view: Cadaveric anatomical study.

Background: The anterior wall of the cavernous sinus (CS) represents an important landmark for endoscopic surgery that although mentioned before, no precise anatomical boundaries have been described. We describe the anatomical landmarks that delimit the anterior wall of the CS, emphasizing its importance as a reference for accessing the CS through endoscopic approaches. Methods: Six adult cadaveric heads fixed with formaldehyde and injected with colored silicone were studied. In all the heads, an endonasal endoscopic approach to the sellar and parasellar regions was performed and the anatomy of the anterior wall of the CS was studied. Results: Four consistent anatomical landmarks that mark the limits of the anterior wall of the CS were found in all the specimens: anterosuperiorly, the lateral opticocarotid recess; posterosuperiorly, the medial opticocarotid recess; anteroinferiorly, the inferior part of the maxillary strut; and posteroinferiorly, the superolateral angle of the clival recess. Conclusion: It is of paramount importance to recognize the anatomical landmarks that define the limits of the anterior wall of the CS to achieve a safe access to this so complex region.

Neuropsychiatric Effects in Patients With Invasive Prolactinomas Treated With Cabergoline.

Background and objective Invasive prolactinoma accounts for 1-5% of all prolactinomas. Its mass and compromise of the diencephalon and frontal and temporal lobes may result in a range of neuropsychiatric symptoms that are often missed during initial evaluations. Cabergoline is a dopaminergic agonist used as the first-line treatment for these patients; however, its effect on neuropsychiatric symptoms in this particular setting remains unexplored. In this study, our primary objective was to describe the epidemiology of neuropsychiatric comorbidities in Mexican patients with invasive prolactinomas. The secondary aim of the study was to describe how these comorbidities are modified by treatment with cabergoline, through follow-up with standardized clinical scales. Methods This was a retrospective analytic study. Data were pulled from clinical records and evaluations of patients at baseline and at six-month follow-ups.  Results A total of 10 patients were included in the study. None of them had any prior psychiatric diagnosis. At the initial evaluation, 70% were diagnosed with depression or anxiety. During follow-up, two patients developed neuropsychiatric symptoms; there was a significant reduction in tumor size but no difference was found in clinimetric scores for neuropsychiatric comorbidities. Conclusions Patients with giant prolactinomas may present with several neuropsychiatric symptoms throughout the course of their disease. Although there are several mechanisms involved, it is important to keep in mind that cabergoline may interfere with the dopaminergic pathways involved. This study was underpowered to determine the association but can serve as a pilot for further research on this topic.

Immunohistochemical Expression of Ki-67, Dopamine D1 and Dopamine D2 Receptors in Meningiomas in a Tertiary Institution in Mexico.

Objectives Meningiomas (MNGs) are the most common intracranial tumors found in the adult population. While most intracranial MNGs may be surgically removed, a subset of patients remains ineligible for conventional treatment. This is either because of a lack of surgical access or due to atypical, anaplastic or invasive characteristics of the tumors. These patients may benefit from targeted therapies that focus on cell receptor expression. The aim of this study was to assess dopamine receptor (DR) and Ki-67 expression in the MGNs of patients treated with surgery in the Instituto Nacional de Neurología y Neurocirugía, Mexico. Materials and methods This study analyzed 23 patients with confirmed MNG diagnoses (10 female and 13 male (mean age: 44.5 years)) who had undergone surgical resection between 2010 and 2014 at our institution. In the collected samples, we performed analyses for Ki-67, Dopamine 1 and Dopamine 2 receptors' expression. Results For the markers Ki-67, DR-D1 and DR-D2, the mean percentual expressions were 18.9%, 23.02% and 8.33%. No significant correlation was found between the expressions of these receptors and the studied MNG characteristics. The expression index of Ki-67 showed a significant relation with mean age (p = 0.03) and prolactin levels (p = 0.02). Conclusions Samples showed varied expressions of the studied receptors. Despite the difference in expressions between the markers, more studies are needed to confirm the findings. In contrast to previous studies, we could not find any relationship between D2-R and tumor characteristics.

Risk Factors Associated With Neurological and Extra-Neurological Complications and Mortality in Patients With Stroke.

Introduction Understanding when and how systemic complications can occur after an acute stroke is crucial. It is important to identify patients who are at higher risk for these complications. Early and effective treatment based on this knowledge can significantly improve patient outcomes. The objective of this study was to identify the risk factors associated with neurological and extra-neurological complications and mortality in stroke patients treated at a secondary care hospital. Methods Of a total of 170 patients diagnosed with hemorrhagic/ischemic stroke and transient cerebral ischemia at a secondary care hospital in Mexico, the records of 125 were reviewed and of these, 86 were included in the study. The study group comprised 86 adult patients (> 18 years of age) diagnosed with ischemic or hemorrhagic stroke or transient cerebral ischemia. Their demographics, clinical characteristics, in-hospital complications, and mortality were retrospectively analyzed.  Results Of the 86 patients examined, 34.9% experienced complications, regardless of the type of stroke. The most significant factor associated with mortality and complications during hospitalization in patients with stroke was previous diseases. Other factors that were linked to higher mortality were pre-existing medical conditions. The most common neurological complication among patients with stroke during hospitalization was intracranial hypertension (3.5%). As for extra-neurological complications, pressure ulcers and nosocomial pneumonia had an occurrence rate of 4.7%. Conclusions The main neurological complication during hospitalization of patients with stroke was intracranial hypertension, while the extra neurological complications were pressure ulcers and nosocomial pneumonia.

Epidemiology of Intracranial Meningiomas in Mexico: Cohort of the National Institute of Neurology and Neurosurgery During the Last Decade.

Introduction Meningiomas have been described as slow-growing neoplasms with benign behavior derived from the connective tissue surrounding the brain and spinal cord. Meningiomas represent one-third of primary central nervous system (CNS) tumors. The World Health Organization (WHO) initially classified them into three groups based on their histopathological characteristics, recently incorporating molecular patterns. Small cohorts have been reported in Latin America compared to the international literature. Ignoring the epidemiology of meningiomas in this region and considering this limitation, we aim to study the epidemiology of meningiomas in our country, Mexico. Material and methods A historical cohort was carried out on 916 patients diagnosed with intracranial meningiomas from January 2008 to January 2021, considering sociodemographic, topographic, and histopathological characteristics. Results In this study, 69.4% (n=636) of patients were women with a mean overall age of 47.53 (SD=14.85) years; 79.6% (n=729) of the lesions were supratentorial with convexity meningiomas being the most prevalent at 32.6% (n=299). Histopathologically, transitional (45.7%) (n=419), meningothelial (22.1%) (n=202), and fibroblastic (16.7%) (n=153) meningiomas were the most frequent. We found significant differences between men and women in age (p=0.01), infra or supratentorial presentation (p<0.001), location of the lesion (p<0.001), and histopathological characteristics (p<0.001). Conclusions Our results are consistent with what has been reported; however, until now, it appears as the largest series reported in our country and Latin America.

Relative cerebral blood volume as response predictor in the treatment of recurrent glioblastoma with anti-angiogenic therapy.

BACKGROUND: Glioblastoma is one of the most common brain tumors in adult populations, usually carrying a poor prognosis. While several studies have researched the impact of anti-angiogenic therapies, especially anti-VEFG treatments in glioblastoma, few have attempted to assess its progress using imaging studies. PURPOSE: We attempted to analyze whether relative cerebral blood volume (rCBV) from dynamic susceptibility-weighted contrast-enhanced MRI (DSC-MRI) could predict response in patients with glioblastoma undergoing Bevacizumab (BVZ) treatment. METHODS: We performed a retrospective study evaluating patients with recurrent glioblastoma receiving anti-angiogenic therapy with BVZ between 2012 and 2017 in our institution. Patients were scheduled for routine MRIs at baseline and first-month follow-up visits. Studies were processed for DSC-MRI, cT1, and FLAIR images, from which relative cerebral blood volume measurements were obtained. We assessed patient response using the Response Assessment in Neuro-Oncology (RANO) working group criteria and overall survival. RESULTS: 40 patients were included in the study and were classified as Bevacizumab responders and non-responders. The average rCBV before treatment was 4.5 for both groups, and average rCBV was 2.5 for responders and 5.4 for non-responders. ROC curve set a cutoff point of 3.7 for rCBV predictive of response to BVZ. Cox Multivariate analysis only showed rCBV as a predictive factor of OS. CONCLUSION: A statistically significant difference was found in rCBV between patients who responded and those who did not respond to BVZ treatment. rCBV may be a low-cost and effective marker to assess response to Bevacizumab treatment in GBM.

Obstructive Hydrocephalus Due to Posterior Fossa Tumors in Adults: A Comparative Analysis of 3 Surgical Techniques.

BACKGROUND: The main treatments for hydrocephalus due to posterior fossa tumors are tumor resection with or without an external ventricular drain, ventriculoperitoneal shunt (VPS), and endoscopic third ventriculostomy. Although preoperative cerebrospinal fluid diversion by any of these techniques improves clinical outcomes, evidence comparing the efficacy of these techniques is scarce. Therefore, we aimed to retrospectively evaluate each treatment modality. METHODS: This single-center study analyzed 55 patients. Treatments were classified as successful (hydrocephalus resolution with a single surgical event) or failed and compared with a χ2 test. Kaplan-Meier curves and log-rank tests were employed. A Cox proportional hazard model was used to determine relevant covariates predicting outcomes. RESULTS: Mean patient age was 36.3 years, 43.4% of patients were men, and 50.9% of patients presented with uncompensated intracranial hypertension. Mean tumor volume was 33.4 cm3, and extent of resection was 90.85%. Tumor resection with or without an external ventricular drain was successful in 58.82% of cases, VPS was successful in 100%, and endoscopic third ventriculostomy was successful in 76.19% (P = 0.014). Mean follow-up time was 15.12 months. Log-rank test found statistically significant differences between survival curves of treatments (P = 0.016) favoring the VPS group. Postoperative surgical site hematoma was a significant covariate in the Cox model (hazard ratio = 17; 95% confidence ratio, 2.301-81.872; P = 0.004). CONCLUSIONS: This study favored VPS as the most reliable treatment of hydrocephalus due to posterior fossa tumors in adult patient; however, several factors influence clinical outcomes. We proposed an algorithm based on our findings and other authors' findings to facilitate the decision-making process.

Assessing the Malignancy Risk of a Meningioma by Its Location.

BACKGROUND: Meningiomas represent 30% of primary intracranial tumors. The current incidence is up to 4.5 cases per 100,000 habitants worldwide. Although there is no prognostic difference among benign histopathological subtypes, atypical meningiomas and malignant meningiomas (WHO grade II and III respectively) may extend to the adjacent brain parenchyma, dura mater, and osseous tissue with a recurrence score (21-49%). This manuscript analyzes the malignancy risk according to neoplastic localization through a logistic retrospective analysis from a total sample of 452 patients with grade I, II, and III (WHO) meningiomas. METHODS: Detailed data collection through a three-year retrospective analysis (January 2008 to December 2011) was applied at Mexico's National Neurology and Neurosurgery Institute including patients with intracranial or spinal-cord meningioma, preoperative imaging study availability and post-surgical histopathological diagnosis. Formal written consent was not required with a waiver by the appropriate national research ethics committee in accordance with the provisions of the regulations of the general health law of Mexico. RESULTS: Convexity lesions displayed an increased risk of malignancy turning for non-benign meningiomas with an odds ratio of 3.1 (95% CI 1.6 to 5.7, p=0.0002) meanwhile skull-base meningiomas present an inverse risk with an odds ratio of 0.4 (95% CI 0.2 to 0.9, p=0.02), as well as spinal-cord meningiomas with an odds ratio of 0.3 (95% CI 0.1 to 0.9). CONCLUSION: Skull base and spinal cord meningiomas usually have benign behavior, meanwhile grade II or III meningiomas within this location are rare. The present work provides an additional criterion for decision making, according to the meningioma's location.

Clinical, Therapeutic, and Prognostic Experience in Patients With Glioblastoma.

BACKGROUND: Glioblastoma (GB) represents the most aggressive type of glioma with a poor prognosis despite the therapies used. As of today, data availability for therapeutic and prognosis experiences is limited. The cornerstone for this study is to create a framework overview of Mexico´s experience throughout 17 years of research. METHODS: Retrospective analysis from 2000 to 2017 including patients with a histological diagnosis of GB was performed. Data were collected from the ABC Medical Center and the Neurology and Neurosurgery National Institute. RESULTS: One hundred and thirty-seven patients were included with a mean age of 54 years. Histological diagnosis was made in all patients, of which 58.1% had a total resection, 31.6% had a partial resection, and 10.3% of them underwent biopsy. In all cases, patients received treatment under the following conditions: 10 patients were treated exclusively with stereotactic radiotherapy (RT). In 55 patients, a combination of RT and TMZ was used, the other 40 patients received RT plus CBP. Eighteen patients RT added to nitrosourea medication and lastly, 14 patients received a combination of RT/TMZ and Bevacizumab, a monoclonal antibody that inhibits the formation of blood vessels (BVZ). The progression-free survival (PFS) and overall survival (OS) were higher in the RT/TMZ/BVZ group (16.5 to 22.9 months) and the RT/TMZ group (11 to 17 months), the prognostic parameters included: Isocitrate dehydrogenase 1 mutation (IDH1), usage of BVZ and TMZ in the PLS and OS, considering as well, age range (<70 years) as a favorable prognostic factor. CONCLUSIONS: GB represents the most frequent intracranial neoplasia. Combined fractionated stereotactic RT added to Temozolomide and Bevacizumab received in our population reports favorable and superior results compared to the ones described in the literature. Further studies are necessary to know the biological behavior of our population.

Characteristics and Long-Term Outcome of Cerebellar Strokes in a Single Health Care Facility in Mexico.

Objective The purpose of this study was to analyze and discuss the clinical characteristics, long-term outcome, and prognostic factors of cerebellar strokes treated in a single health care facility in Mexico. Methods We retrospectively reviewed the medical records of adult patients admitted to our hospital with diagnosis of cerebellar ischemic and hemorrhagic stroke between 2018 and 2020. Baseline data included sociodemographic and radiological variables, treatment (surgical versus conservative), and Glasgow Coma Scale on arrival (GCSOA). The final neurological outcome was evaluated with the Glasgow Outcome Scale (GOS) six months after hospital discharge. Results Ten patients (seven male and three female) with a mean age of 57.9 ± 9.3 years were included, six with cerebellar ischemic infarction and four with cerebellar hemorrhage. Out of the 10 patients, four underwent surgery (suboccipital decompressive craniectomy {SDC} ± ventriculostomy). The outcome was favorable in four cases (40%) and unfavorable in six (60%). Patients who underwent surgical treatment fared worse with all four cases associating poor outcome. The comparison between good and poor outcome groups showed significant differences in the presence of obstructive hydrocephalus (one versus six, p = 0.05) and poorer GCSOA (6.16 ± 1.72 versus 12.5 ± 3.6, p = 0.05), associating poorer outcome. Conclusion There is still controversy regarding the appropriate management of cerebellar strokes. The presence of obstructive hydrocephalus and poorer GCSOA are associated to worse outcomes.

Fahr's Syndrome for Primary Hypoparathyroidism in a Patient With COVID-19.

Fahr's syndrome, recently named "primary brain calcification," is a rare disorder with a variable clinical presentation ranging from behavioral changes to seizures. It can be idiopathic or have multiple causes, hypoparathyroidism the most frequent. In the current coronavirus 2019 (COVID-19) pandemic, these electrolyte imbalances have acquired importance, and there has been a correlation between the lowest serum calcium levels and severe COVID-19 disease. It is known that calcium accomplishes many normal physiologic functions. We present a case of a 63-year-old woman who arrived at the emergency room with a fever of 10-day duration, odynophagia, dry cough, dyspnea, and drowsiness. Upon her arrival, computed tomography of the brain and chest was performed, showing areas of calcification in the basal nuclei and infiltrates with a ground-glass pattern, respectively. In addition, laboratory studies were conducted in which hypocalcemia and hyperphosphatemia stand out. Furthermore, a positive result was obtained from acute Respiratory Syndrome Coronavirus 2 (SARS-COV2) from bronchial secretion. According to the clinical presentation data in the imaging and laboratory studies, Fahr's syndrome and COVID-19 pneumonia were diagnosed. We consider evaluating electrolyte imbalances at case presentations essential and continuously monitoring them. Appropriate and prompt corrections were achieved in patients with hypoparathyroidism history and severe COVID-19 disease. This case shows the vital collaboration between endocrinologists and other physicians that care for patients with COVID-19 infection.

Case Report of a Hemangioblastoma With Large Blood Vessels and Rare Vascular Anomalies: Is It Fibromuscular Dysplasia or Arteriovenous Malformation Association?

Hemangioblastoma is considered a benign neoplasm characterized by abnormal vasculature and stromal cells; several pathophysiological mechanisms have been proposed, such as genetic predisposition, hormonal factors, and arterial wall ischemia. Fibromuscular dysplasia is characterized by hyperplasia or thinning of the smooth muscle, elastic fibre destruction, fibrous tissue proliferation, and arterial wall disorganization. We present a cerebellar hemangioblastoma case not associated with Von Hippel Lindau syndrome. Histologically we evidenced big vessels with anomalies of the vascular walls corresponding to fibromuscular dysplasia, and those changes have not been described in these types of tumors. In this light, rare findings could be called vascular malformations or degenerative vascular changes, fibromuscular dysplasia or vascular anomalies. Arterio-venous malformation and hemangioblastoma pathology are rarely presented together. Notwithstanding, we could say that it is a stromal stem cell tumor in a varied stage of differentiation.

Carboplatin Plus Vincristine as an Alternative Chemotherapeutic Scheme in Patients With Glioblastoma.

Background and objective Alternative chemotherapy regimens, including cisplatin, carmustine, or other agents, have been shown to be effective; however, the use of carboplatin plus vincristine (C/V) has not been studied before. In this study, we aimed to determine the survival rates in patients treated with C/V, by comparing our findings with treatments based on temozolomide (TMZ), and to explore a possible relationship with the methylation status of the methylguanine methyltransferase (MGMT) promoter in patients with glioblastoma (GB). Methods A retrospective cohort study was conducted involving 45 surgically treated patients diagnosed with GB. Fresh tissue samples were examined by the DNA bisulfite conversion method to determine methylation status. After surgery, different chemotherapy regimens were employed as adjuvants. Follow-up of participants was performed as outpatients at three-month intervals to determine overall survival (OS), by comparing the use of TMZ versus C/V. Results MGMT promoter methylation status could only be determined in 35 samples; 20 patients received adjuvant chemotherapy, of which 14 were treated with C/V and six with TMZ-based schemes. The median OS (mOS) was eight months (range: 1-24 months). OS was 57.25% at six months, 48.7% at 12 months, and 28.5% at 24 months. In the TMZ group, an OS of 83% was observed at 24 months. In the C/V group, OS was 71.4% at six months, 57.1% at 12 months, and 35.7% at 24 months. Patients who did not receive adjuvant chemotherapy treatment had the lowest survival rates with an OS of 39.9% at six months, 26.6% at 12 months, and 19.9% ​​at 24 months. Conclusions Based on our findings, C/V offers an accessible and effective alternative treatment when the TMZ-based scheme is not accessible, providing higher rates of OS compared to patients without chemotherapy management. The methylation status of the MGMT promoter is a significant prognostic factor, resulting in higher survival rates among patients when it is methylated.

Neurenteric Cyst of the Posterior Cranial Fossa: A Case Report and Literature Review.

Neurenteric cysts (NCs) are rare benign endodermal lesions of the central nervous system (CNS), most commonly found in the spinal cord. Intracranial lesions are rare, among which the posterior fossa appears to be the predominant location. We present a case of a 60-year-old man who presented with a suddenly decreased level of consciousness. After a series of radiological studies were done, a multilobulated cystic lesion in the right posterior fossa was observed. Surgical resection was performed and based on its histopathological characteristics, NC diagnosis was confirmed. Because of the wide list of differential diagnoses and low specificity of radiological features, surgical gross total resection remains the most effective treatment, followed by diagnosis confirmation through histopathological techniques.

Giant Posterior Inferior Cerebellar Artery Aneurysm Mimicking a Brainstem Tumor.

Aneurysms from the vertebrobasilar system are rare, accounting for only 5%-10% of all intracranial aneurysms. The most common sites in which these lesions occur are the bifurcation of the basilar artery and the origin of the posterior inferior cerebellar artery (PICA). When the aneurysms present in the distal portion of the PICA, they represent from 0.5% to 6%. These aneurysms are called giant when they exceed 25 mm in diameter. We present a case of a 49-year-old male who presented with acute obstructive hydrocephalus, which required ventriculoperitoneal shunting and left hemispheric cerebellar syndrome. The magnetic resonance imaging study revealed an occupative mass located in the fourth ventricle, and diagnostic angiography showed a partially thrombosed giant saccular aneurysm in the posterior inferior cerebellar artery. He underwent surgical management via a lateral suboccipital approach. The aneurysm was remodeled and clipped successfully without complications, with an uneventful postoperative course. Although rare, PICA aneurysms should always be considered when posterior fossa syndrome occurs, including brainstem and cranial nerve compression symptoms. It can easily be misdiagnosed as a neoplastic lesion, especially when the aneurysm reaches big or giant size. Therefore, complete diagnostic studies, such as cerebral angiography, must be performed. Surgical clipping must be offered as the first line of treatment. It provides occlusion of the aneurysm and relieves compressive symptoms.

Neuroprotective effect of dapsone in patients with aneurysmal subarachnoid hemorrhage: a prospective, randomized, double-blind, placebo-controlled clinical trial.

OBJECTIVE: In this study, the authors sought to define the differences in the incidence of delayed cerebral ischemia (DCI) between patients treated with dapsone and those treated with placebo. Secondary objectives were to define the clinical outcome at discharge and 3 months and the incidence of brain infarction. METHODS: A prospective, randomized, double-blind, placebo-controlled study was performed and included patients with aneurysmal subarachnoid hemorrhage (SAH) within 5 days from ictus who were candidates for aneurysm occlusion, and who had a Fisher grade of 3 or 4. Patients with sulfa or sulfone drug allergies, hemoglobin < 11 g/dl, known G6PD deficiency, and those refusing informed consent were excluded. A minimal relevant effect decrease of 35% in the incidence of DCI was established. Patients were randomly assigned to receive a regimen of dapsone 2.5 ml (100 mg) daily or a placebo (aluminum hydroxide suspension, 2.5 ml daily). Both groups received validated treatment for aneurysmal SAH. The appearance of DCI on CT was assessed in every patient at discharge and 3 months later. We used the chi-square test to compare the DCI incidence between both groups, and the Student t-test or nonparametric tests to compare quantitative variables. RESULTS: Overall, 48 patients (70.8% women and 29.2% men) were included. The mean age was 50 years (SD 14.28 years, range 18-72 years). Prerandomization and postrandomization characteristics were balanced, except for the necessity of intra-arterial nimodipine administration in patients treated with placebo (15.4% vs 45.5%, p = 0.029. The incidence of DCI, the primary endpoint, for the whole cohort was 43.8% and was significantly lower in the dapsone group (26.9% vs 63.6%, p = 0.011). In addition, the irreversible DCI incidence was lower in the dapsone group (11.5% vs 54.5%, p = 0.12). A favorable modified Rankin Scale score was more frequent in the dapsone group at discharge and at 3 months (76.9% vs 36.4%, p = 0.005 and 80% vs 38.9%, p = 0.019, respectively). Also, the brain infarction incidence was lower in the dapsone group (19.2% vs 63.6%, p = 0.001). There was no difference between groups regarding adverse events. CONCLUSIONS: Dapsone seems to play a role as a prophylactic agent in patients at high risk of developing DCI after aneurysmal SAH. A multicenter investigation is necessary to increase the study population and confirm the consistency of the results observed in this study.