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.

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.

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.

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.

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.

Metastatic primary brain rhabdomyosarcoma in a pediatric patient: illustrative case.

BACKGROUND: Primary intracranial rhabdomyosarcoma is an extraordinarily rare malignant tumor, with even fewer presenting with distant metastasis. To date, only five cases, including the one presented here, have been reported to present metastatic activity. OBSERVATIONS: A 12-year-old boy presented with a few days of headache, nausea, vomiting, but no neurological deficit. Brain computed tomography and magnetic resonance imaging demonstrated hydrocephalus and a cystic lesion with left parieto-occipital extension. After resection, pathology reported primary rhabdomyosarcoma, with positive desmin and myogenin on immunohistochemistry. The patient presented with pulmonary metastasis. The patient had an overall survival of 21 months after diagnosis with optimal treatment. LESSONS: Rhabdomyosarcoma is a malignant neoplasm arising from undifferentiated skeletal muscle cells, with morphological, immunohistochemical, ultrastructural, or molecular genetic evidence of primary skeletal muscle differentiation. It presents with a rapidly worsening clinical course and the final outcome is poor. Treatment is widely based on protocols that have been proven to be effective in extracranial versions of these tumors, although repeatedly ineffective. Primary brain rhabdomyosarcoma poses a diagnostic challenge because of its infrequent presentation, grade of undifferentiation and tumor heterogeneity. Immunohistochemical and genetic testing have proven to be useful tools for diagnosis.

The Role of Biochemical and Respiratory Markers in the Mortality of Patients With SARS-CoV-2 Infection in a Mexican Population.

BACKGROUND: The SARS-CoV-2 pandemic has challenged the traditional perspectives of health care. The objective of our study was to analyze the association of different hematological biomarkers and respiratory assistance with the disease's severity and mortality in COVID-19. MATERIALS AND METHODS: A single reference center, cross-sectional, retrospective, descriptive and analytical, observational study was carried out on 362 SARS-CoV-2 positive adults from April to October 2020. RESULTS: The mean age of the population was 55.92±13.12 years. A distribution by gender of n=227 (63.0%) men and n=135 women (37.0%) was found. Mortality occurred in 14% of the studied population. Comorbidities associated were hypertension n=128 (35.0%) and diabetes n=112 (31.0%). Of the 362 patients, 64 required advanced ventilatory support when taken to the intensive care unit, of these 39 (60.9%) died and only 25 (39.1%) survived (p<0.0001). On the other hand, biochemical indicators such as CRP, D-dimer, DHL, lymphocytes, leukocytes, neutrophils, and the neutrophil/lymphocyte ratio, showed a significant difference (p<0.0001) at admission and during the stay in the intensive care unit. CONCLUSIONS: Patients who required ventilatory assistance showed an increased risk of mortality, as did those who were admitted to the intensive care unit. Higher mortality was associated with higher values ​​of CRP, DHL, D-dimer, neutrophil/lymphocytes ratio, total leukocytes, and lower lymphocytes.

Transient ventriculoperitoneal shunt malfunction in a pediatric patient: An illustrative case.

BACKGROUND: Ventriculoperitoneal shunt (VPS), the mainstay of the treatment for hydrocephalus, is associated with relatively high revision rates. Transient hydrocephalus due to intermittent VPS obstruction should be recognized as a cause of VPS malfunction. While transient VPS dysfunction is well-recognized complication, there is a relative paucity of well-documented cases in the literature. CASE DESCRIPTION: We present the case of a 4-year-old boy with a history of vascular malformation and hydrocephalus secondary to intraventricular hemorrhage. The patient presented with transient, self-resolving hydrocephalus (without intervention), as documented by clinical and radiological findings. CONCLUSION: Transient hydrocephalus due to intermittent VPS dysfunction in children is a rare entity, but it should be suspected in certain patients with VPS presenting with transient or self-improving symptoms.

Endoport-assisted microsurgical treatment for a ruptured posterior cerebral artery aneurysm: A technical note.

Posterior Cerebral Artery aneurysms are scarce, yet its territory is frequently associated to large and giant aneurysms. Treatment is mostly a binary option between microsurgical clipping and endovascular coiling. Hybrid approaches are an option too, whereas innovation with less frequent techniques such as endoscope-controlled and endoscope-assisted procedure may provide a safer surgical approach with same successful results. Hereby we report a case of a 53 years old male examined at the ER after presenting generalized seizures and altered state of consciousness. Upon arrival, neurological evaluation revealed homonymous right hemianopia. Computed tomography (CT) scan revealed a subarachnoid hemorrhage and left parieto-occipital intraparenchymal hemorrhage with intraventricular extension; computed tomography angiogram (CTA) revealed an aneurysm at the left posterior cerebral artery (PCA) in its P4 segment. We performed a vascular exploration with drainage of the occipital and intraventricular hematoma through a single endoscopic port through transulcal approach guided by neuronavigation, in addition to clipping and aneurysmectomy. The combination of microsurgical clipping with previous Endoport-guided endoscopic procedure may be a surgical-operative option that not only may facilitate the approach to the desired lesion, but also provides a safer surgical scenario.

Reconversion of neurosurgical practice in times of the SARS-CoV-2 pandemic: a narrative review of the literature and guideline implementation in a Mexican neurosurgical referral center.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has forced the modification of surgical practice worldwide. Medical centers have been adapted to provide an efficient arrangement of their economic and human resources. Although neurosurgeons are not in the first line of management and treatment of COVID-19 patients, they take care of patients with neurological pathology and potential severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, the authors describe their institutional actions against the pandemic and compare these actions with those in peer-reviewed publications. METHODS: The authors conducted a search using the MEDLINE, PubMed, and Google Scholar databases from the beginning of the pandemic until July 11, 2020, using the following terms: "Neurosurgery," "COVID-19/SARS-CoV-2," "reconversion/modification," "practice," "academy," and "teaching." Then, they created operational guidelines tailored for their institution to maximize resource efficiency and minimize risk for the healthcare personnel. RESULTS: According to the reviewed literature, the authors defined the following three changes that have had the greatest impact in neurosurgical practice during the COVID-19 pandemic: 1) changes in clinical practices; 2) changes in the medical care setting, including modifications of perioperative care; and 3) changes in the academic teaching methodology. CONCLUSIONS: The Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez" is one of the major referral centers for treating highly complex neurosurgical pathologies in Mexico. Its clinical and neurosurgical practices have been modified with the implementation of specific interventions against the spread of COVID-19. These practical and simple actions are remarkably relevant in the context of the pandemic and can be adopted and suited by other healthcare centers according to their available resources to better prepare for the next event.

Manejo bimodal de aneurismas asociados a malformaciones arteriovenosas cerebrales. Reporte de caso y breve revisión de la literatura.

La patogénesis de los aneurismas intracraneales asociados a malformaciones arteriovenosas cerebrales no es bien entendida y es aún objeto de discusión. Las decisiones sobre cuándo y cómo tratar los aneurismas intracraneales de estas características siempre han sido un reto terapéutico tanto para neurocirujanos vasculares como para terapistas endovasculares neurológicos. Reportamos el caso de una paciente de 51 años con aneurismas múltiples asociados a una malformación arteriovenosa, así como su manejo neuroquirúrgico, con un análisis comparativo con lo publicado en la literatura médica y científica en los últimos 10 años.The pathogenesis of intracranial aneurysms associated with arteriovenous malformations is not well understood and is still under discussion; the decisions about when and how to treat intracranial aneurysms of these characteristics have always been a therapeutic challenge for both, vascular neurosurgeons and endovascular neurological therapists. We report the case of a 51-year-old patient with multiple aneurysms associated with arteriovenous malformation, as well as her neurosurgical management, with a comparative analysis what has been published in the medical and scientific literature in the last 10 years.

Usefulness and safety from stereotactic biopsy in posterior fossa lesions in adult patients.

BACKGROUND: Stereotactic biopsy has been reported as a useful and safety procedure in pediatric patients. In adult patients exist more controversy because a greater number of diagnostic options. OBJECTIVE: To demonstrate its usefulness and safety in adult patients with posterior fossa pathology. METHOD: From 2006-2014, 23 patients were operated from posterior fossa. Variables: age, gender, state, pre- and postoperative diagnosis, stereotactic device, location and complications. RESULTS: 52.2% females and 47.8% males. The location was ponto-mesencephalic 43.5%, cerebellum 39.1%, bulbar 13% and pineal region 4.3%. The preoperative diagnosis was brainstem glioma 78.2%, lymphoma 8.7%, and meningioma, metastasis and abscess 4.3% each one. In 73.9% Zamorano-Dujovni device was used and in 26.1% the CRW. The definitive diagnosis was pilocytic astrocytoma 17.4%, diffuse astrocytoma 13%, inflammatory response 13%, anaplastic astrocytoma 8.7%, gliosis 8.7%, glioblastoma, neuroectodermic primitive tumor, germinoma, pineocytoma and cryptococcosis 4.3% each one. In 17.4% there was no diagnosis. The preoperative diagnosis was concordant in 43.5%. One transient deficit and one pin displacement 4.3% were present. 91.4% without complications. CONCLUSIONS: It is a useful, necessary and safety procedure in adult patients.

ANTECEDENTES: La biopsia por estereotaxia ha sido reportada como segura y útil en pediatría. En adultos es más controvertida debido a la mayor diversidad de opciones diagnósticas. OBJETIVO: Demostrar su utilidad y seguridad en pacientes adultos con patología de fosa posterior. MÉTODO: En 2006-2014 se operaron 23 pacientes de fosa posterior. Variables: edad, sexo, diagnóstico preoperatorio y posoperatorio, estereotáctico, localización y complicaciones. RESULTADOS: 52.2% mujeres y 47.8% hombres. La localización fue la región pontomesencefálica en el 43.5%, el cerebelo en el 39.1%, bulbar en el 13% y pineal en el 4.3%. El diagnóstico preoperatorio fue glioma de tallo en el 78.2%, linfoma en el 8.7% y meningioma, metástasis y absceso en el 4.3% cada uno. En el 73.9% se utilizó el sistema Zamorano-Dujovni y en el 26.1% el CRW. El diagnóstico definitivo fue astrocitoma pilocítico en el 17.4%, astrocitoma difuso en el 13%, respuesta inflamatoria en el 13%, astrocitoma anaplásico en el 8.7%, gliosis en el 8.7%, y glioblastoma, tumor neuroectodérmico primitivo, germinoma, pineoctioma y criptococosis en el 4.3% cada uno. En el 17.4% no hubo diagnóstico. El diagnóstico preoperatorio fue concordante en el 43.5%. Hubo un déficit transitorio y un desplazamiento de uno de los pinchos en el 4.3% de los casos. En el 91.4% no hubo complicaciones. CONCLUSIONES: Es un procedimiento útil, necesario y seguro en pacientes adultos.

Locking Stand-Alone Cage Constructs for the Treatment of Cervical Spine Degenerative Disease.

Study Design: Prospective case series study. Purpose: Description of the outcome of stand-alone cervical cages for single and multilevel cervical degenerative spine disease. Overview of Literature: The aim of anterior cervical discectomy and fusion (ACDF) for cervical spine disease is to improve patient symptoms and spine stability and restore lordosis. Locking stand-alone cages were developed with the goal of minimizing soft tissue disruption anterior to the vertebrae and reducing the profile of the construct by avoiding an anterior plate, thereby maximizing ACDF benefits. Methods: This study comprises a case series of patients surgically treated between July 2015 and February 2018 who received single or multilevel ACDF with a zero-profile stand-alone cervical cage. Surgical and clinical preoperative evaluation and surgical outcomes were evaluated using pre- and postoperative Nurick, Visual Analog Scale (VAS), Neck Disability Index (NDI), Japanese Orthopedic Association (JOA) score for myelopathy scales, cervical Cobb angles, postoperative surgical complications, and fusion and subsidence rates. Results: Fifty-three patients underwent ACDF; the mean age of these patients was 58.8 years, and their preoperative VAS, NDI, and JOA scores were 8.1, 31.6, and 15.3, respectively. The preoperative Cobb angle was 30.7°. Forty-five percent of patients had onelevel, 54.7% had two-level, and 13.2% had three-level procedures. On preoperative magnetic resonance imaging, foraminal stenosis was present in 94.3% of patients, whereas medullar stenosis was present in 41.5%. The rate of complications was 5.7%: two patients had postoperative dysphagia (3.7%), and one patient had a surgical site hematoma. Mean postoperative follow-up time was 6.7 months; postoperative VAS, NDI, and JOA scores were 2.4, 15.9, and 15.8, respectively. Postoperative Cobb angle was 35.9°, fusion rate was 84.9%, and subsidence rate was 11.3%. Conclusions: ACDF with zero-profile stand-alone cervical devices is an excellent option for cervical degenerative disc disease of one, two, and three levels, with similar results reported when using ACDF with either cage or plate.