Assessing the cadmium content of cacao crops in Arauca, Colombia.

The district of Arauca is the second-largest producer of cacao in Colombia. However, despite its quality, it faces issues for export due to levels of cadmium (Cd) higher than the regulatory thresholds. A central question is how it may impact agricultural performance in the presence of Cd in cacao and chocolates. This study quantified Cd in cacao plantations from Arauca. Thus, 180 farms were assessed in the municipalities of Arauquita, Fortul, Saravena, and Tame. Five sample types (soil, irrigation channel sediment, soil litter, cacao seeds, and chocolates) were assessed for Cd. As a technological innovation, the new MXRF technology was used for Cd in chocolates. The sequence of Cd content was soil litter > chocolate > soils > cacao seeds > irrigation-channel sediment. A gradient north-south of Cd content in soil was observed, where highest content was found in farms near the Arauca River, and lower farther away. In irrigation channel sediment, Cd levels averaged 0.07 mg kg-1. The Cd content in cacao seeds was 0.78 mg kg-1 on average. Cd content in chocolates was above the threshold (1.10 mg kg-1 on average, including several cacao mass percentages). These artisanal chocolate bars produced by single farms were near the limit of Cd set by the European Union (up to 0.8 mg kg-1). Therefore, mixing beans from different farms could reduce their Cd content. The present study underscores the complexity of Cd distribution, emphasizing the importance of integrating soil, crop, and landscape features in managing and mitigating Cd levels in cacao.

Cacao (Theobromacacao L.) climate zones and its associated agrobiodiversity in Arauca, Colombia.

Background: Cacao (Theobromacacao L) is one of the most relevant crops in terms of economy and social rural development in Colombia. Cacao is also an important crop due to its potential to replace illicit crops and it is related to less deforestation and preserves the biodiversity. There are several cacao districts in Colombia, one of these being Arauca. The Department of Arauca is the second largest cocoa producing region in Colombia; however, it is heavily affected by armed conflict. To raise the knowledge and technology available in the region, integrating data on the occurrence of cacao farms with climatic variables becomes a powerful socioeconomic mapping tool for maintaining agrobiodiversity and food security in the region. Consequently, this type of agrodiversity data and agroclimatic approaches help to better manage agrobiodiversity, as in the cacao region of Arauca. These tools are even more relevant in biodiverse regions, such as flooded savannahs and tropical forest ecosystems, which are currently undergoing drastic changes due to agricultural expansion and climate change. One of the knowledge gaps in Colombia´s cacao regions is that there are currently no agroclimatic maps made with a social and scientific approach. This study aimed to provide a database of the spatial distribution of cacao farms in Arauca, as well as agroclimatic maps that identify and locate cacao climate regions in Arauca. We also present a presence-only matrix consisting of twenty-six tree species, or agrobiodiversity, distributed across the study region and specifically associated with the cacao forestry systems in Arauca. New information: We present the first database of both climate and agrobiodiversity data related to cacao farms in Arauca, developed with a research and socioeconomic vision that generated a novel approach for the agroclimatic zoning of cocoa in the Arauca Region and Colombia. Using 1,538 cacao farms at the regional scale, we identified two national and six regional-scale climate and soil regions. The selection at the local scale allowed us to classify 180 cacao farms comprising nine agroclimatic clusters in Arauca. We found twenty-six tree species distributed across the cacao climate zones. This dataset and its related maps also represent the agrobiodiversity of cultivated cacao locally. This is the most complete climate and agrobiodiversity dataset of cacao farms distribution in one of the top cocoa-producing regions in the country. These outputs are crucial because they constitute a baseline for developing research in the biodiversity of agroforestry systems, pests and diseases, pollutant presence, genetics, post-harvest processing and cocoa quality and safety.

Cannabidiol Modifies the Glutamate Over-Release in Brain Tissue of Patients and Rats with Epilepsy: A Pilot Study.

Drug-resistant epilepsy (DRE) is associated with high extracellular levels of glutamate. Studies support the idea that cannabidiol (CBD) decreases glutamate over-release. This study focused on investigating whether CBD reduces the evoked glutamate release in cortical synaptic terminals obtained from patients with DRE as well as in a preclinical model of epilepsy. Synaptic terminals (synaptosomes) were obtained from the epileptic neocortex of patients with drug-resistant temporal lobe epilepsy (DR-TLE, n = 10) or drug-resistant extratemporal lobe epilepsy (DR-ETLE, n = 10) submitted to epilepsy surgery. Synaptosomes highly purified by Percoll-sucrose density gradient were characterized by confocal microscopy and Western blot. Synaptosomes were used to estimate the high KCl (33 mM)-evoked glutamate release in the presence of CBD at different concentrations. Our results revealed responsive tissue obtained from seven patients with DR-TLE and seven patients with DR-ETLE. Responsive tissue showed lower glutamate release (p < 0.05) when incubated with CBD at low concentrations (less than 100 µM) but not at higher concentrations. Tissue that was non-responsive to CBD (DR-TLE, n = 3 and DR-ELTE, n = 3) showed high glutamate release despite CBD exposure at different concentrations. Simultaneously, a block of the human epileptic neocortex was used to determine its viability through whole-cell and extracellular electrophysiological recordings. The electrophysiological evaluations supported that the responsive and non-responsive human epileptic neocortices used in the present study exhibited proper neuronal viability and stability to acquire electrophysiological responses. We also investigated whether the subchronic administration of CBD could reduce glutamate over-release in a preclinical model of temporal lobe epilepsy. Administration of CBD (200 mg/kg, p.o. every 24 h for 7 days) to rats with lithium-pilocarpine-evoked spontaneous recurrent seizures reduced glutamate over-release in the hippocampus. The present study revealed that acute exposure to low concentrations of CBD can reduce the glutamate over-release in synaptic terminals obtained from some patients with DRE. This effect is also evident when applied subchronically in rats with spontaneous recurrent seizures. An important finding was the identification of a group of patients that were non-responsive to CBD effects. Future studies are essential to identify biomarkers of responsiveness to CBD to control DRE.

Prognostic factors of unilateral prelemniscal radiations radiofrequency lesions: A surgical technique for the treatment of Parkinson's disease motor symptoms.

OBJECTIVE: A group of patients with Parkinson's disease (PD) were managed with unilateral prelemniscal radiation radiofrequency lesions (U-Raprl). The current study aims to evaluate prognostic factors that could influence clinical response. METHODS: Patients previously diagnosed with PD managed with U-Raprl were included in the study, classifying them into two groups according to their percentage of clinical response ( 1.5), Age (p < 0.0001, ∆ = 2.38), Evolution (p < 0.0001, ∆ = 2.38), and post-operative UPDRS (p < 0.01, ∆ = 1.38). The qualitative analysis of the distribution regarding the responder group shows that those patients with an age under 58 years, an evolution fewer than 7 years, and a preoperative HYS score smaller than 2, showed a response ≥ 50% according to the UPDRS-III in all cases. CONCLUSION: U-Raprl is a highly effective procedure with a 5-year persistence of improvement. The most relevant prognostic factors to consider for a clinical response according to UPDRS-III greater than 50% are age under 58 years, less than 7 years of PD evolution, and HYS less or equal to 3.

Primary spontaneous intracerebral hemorrhage in COVID-19 patients: differences among presentation patterns - A systematic review.

OBJECTIVE: The objective of this study was to determine if there are differences between the presentation patterns of hemorrhagic stroke (HS) associated to COVID-19. METHODS: It was performed a systematic search based on PRISMA guidelines of the cases reported in PUBMED of HS associated to SARS-CoV-2 infection and we added to this sample cases from our own hospital cohort. Patients in the database were separated by groups according to presentation symptoms: if they debuted with neurological symptoms or debuted with pulmonary symptoms. RESULTS: Seventy cases were included in the study. Patients that debuted with pulmonary symptoms accounted for 68.6% of the cases with an interval between the development of symptoms and the presentation of HS of 15.6 days. We found that the use of anticoagulants during hospitalization, multifocal image pattern, and the elevation of D-dimer, Ferritin, and lactate dehydrogenase levels were significantly associated with the group of pulmonary presentation, whereas the presence of hypertension during hospitalization, and a lower hemoglobin level was associated with the group of neurologic symptoms. CONCLUSION: Although HS associated with COVID-19 is a clinical entity with increasing evidence, it is necessary to establish that there are two forms of presentation with their own characteristics.

OBJETIVO: determinar si existen diferencias entre los patrones de presentación de hemorragia intracraneal asociada a COVID-19. PACIENTES Y MÉTODOS: Se realizó una búsqueda sistemática basada en la guía PRISMA de los casos reportados en PUBMED de hemorragia intracraneal asociados a infección por SARS-CoV-2 y se agregaron a esta muestra casos de nuestra propia cohorte hospitalaria. RESULTADOS: se incluyeron 70 casos. Los pacientes que debutaron con síntomas pulmonares representaron el 68.6% de los casos con un intervalo entre el desarrollo de los síntomas y la presentación de la hemorragia intracraneal de 15.6 días. Encontramos que el uso de anticoagulantes durante la hospitalización, el patrón de imagen multifocal y la elevación de los niveles de dímero D, ferritina y deshidrogenasa láctica se asociaron significativamente con el grupo de presentación pulmonar, mientras que la presencia de hipertensión durante la hospitalización, y un nivel de hemoglobina más bajo se asoció con el grupo que debutó con síntomas neurológicos. CONCLUSIÓN: si bien la hemorragia intracraneal asociada a COVID-19 es una entidad clínica con evidencia creciente, es necesario establecer que existen dos formas de presentación con características propias.

Concordance and diagnostic yield of stereotactic biopsies for posterior fossa: Technique and experience in a reference hospital.

AIM: Describe our stereotactic brain biopsy (SBB) technique for intra-axial lesions of the posterior fossa, evaluate its effectiveness and safety, and compare them with other series. MATERIAL AND METHODS: Retrospective study in ten consecutive patients, whose variables were age, gender, location of the lesions, clinical, radiological, and histopathological diagnoses, complications, and mortality, for analysis using descriptive statistics and tests of concordance and diagnostic validity. RESULTS: Lesions were pontine in seven cases, and pontomedullary in three occasions, with histopathological diagnoses of four Grade II astrocytomas, two Grade IV astrocytomas, two infectious process, one neuroblastic tumor, and one cavernous malformation, whose frequency differs from the previous reports (χ2 = 0.07). The clinical-radiological concordance was poor (κ = 0.20). The validity of the clinical diagnosis had intermediate values (Sn = 66.7%, Sp = 75%), while radiological studies were more sensitive (Sn = 100%, Sp = 25%). A definitive diagnosis was obtained in all procedures, with no permanent morbidity or mortality because of the surgery. CONCLUSION: The SBB technique for posterior fossa implemented in our hospital shows high diagnostic yield, as well as absolute safety for the patient.

OBJETIVO: Describir nuestra técnica de biopsia cerebral estereotáctica (SBB) para lesiones intraaxiales de fosa posterior, evaluar su eficacia y seguridad y compararlas con otras series. MATERIAL Y MÉTODOS: Estudio retrospectivo en 10 pacientes consecutivos, cuyas variables fueron edad, sexo, localización de las lesiones, diagnósticos clínicos, radiológicos e histopatológicos, complicaciones y mortalidad, para análisis mediante estadística descriptiva y pruebas de concordancia y validez diagnóstica. RESULTADOS: Las lesiones fueron pontinas en 7 casos y pontomedulares en 3 ocasiones, con diagnósticos histopatológicos de 4 astrocitomas grado II, 2 astrocitomas grado IV, 2 procesos infecciosos, 1 tumor neuroblástico y 1 malformación cavernosa, cuya frecuencia difiere de reportes previos (χ2 = 0.07). La concordancia clínico-radiológica fue mala (κ = 0.20). La validez del diagnóstico clínico tuvo valores intermedios (Sn = 66.7%, Sp = 75%), mientras que los estudios radiológicos fueron más sensibles (Sn = 100%, Sp = 25%). Se obtuvo un diagnóstico definitivo en todos los procedimientos, sin morbimortalidad permanente por la cirugía. CONCLUSIÓN: La técnica SBB para fosa posterior implementada en nuestro hospital muestra un alto rendimiento diagnóstico, así como una seguridad absoluta para el paciente.

Prelemniscal Radiations as a Target for the Treatment of Parkinson Disease - Individual Variations in the Stereotactic Location of Fiber Components: A Probabilistic Tractography Study.

OBJECTIVE: Prelemniscal radiation (Raprl) lesions and deep brain stimulation effectively control motor symptoms of Parkinson disease, but individual variations in the stereotactic location of its fiber components constitute a significant concern. The objective of this study was to determine individual variations in the stereotactic location of fiber tracts composing Raprl. METHODS: Raprl fiber composition was determined in a group of 10 Parkinson patients and 10 matched controls using 3T magnetic resonance imaging, brain imaging processed for diffusion-weighted images, tract density imaging, and constrained spherical deconvolution. The stereotactic position of the point of maximal proximity (PMP), which is the point where the most significant number of fibers is concentrated in the smallest volume in the tractography, was evaluated in the right and left hemispheres of the same person, between individuals and between patients and controls for each tract in coordinates "x," "y," and "z." The stereotactic coordinates at which PMP of all tracts meet were statistically determined, representing the recommended aim for this target. RESULTS: Stereotactic coordinates of the 3 fiber tracts composing Raprl, cerebellar-thalamic-cortical, globus pallidus-peduncle-pontine nucleus, and mesencephalic-orbital frontal cortex, did not vary between right and left hemispheres in the same person and between patients and controls. In contrast, PMP variability between individuals was significant, mainly for the mesencephalic-orbitofrontal tract. Therefore, probabilistic tractography can better determine individual variations to plan electrode trajectories. CONCLUSIONS: Individual PMP variations for fiber tracts in Raprl, identified by probabilistic tractography, provide a platform for planning the stereotactic approach to conform volumes for deep brain stimulation and lesions.

Optimizing deep brain stimulation for the treatment of drug-resistant temporal lobe epilepsy: a pilot study.

OBJECTIVE: The authors sought to determine the antiseizure effects of deep brain stimulation (DBS) of the parahippocampal cortex (PHC) for treatment of drug-resistant mesial temporal lobe epilepsy (MTLE). METHODS: After a 3-month baseline period, 6 adult patients with drug-resistant MTLE and hippocampal sclerosis (HS) had stereoelectroencephalography (SEEG)-DBS electrodes implanted at the PHC for identification of the seizure onset zone (SOZ). Patients entered an 8-month, randomized, double-blind protocol for DBS, followed by a 12-month open-phase study. Monthly reports of seizure frequency were collected, with separate counting of focal seizures with or without awareness impairment (focal impaired awareness seizures [FIAS] or focal aware seizures [FAS], respectively) and focal evolving to bilateral generalized tonic clonic seizures (GTCS). Stimulation parameters were 130 Hz, 450 µsec, 2.5-3 V, and cyclic stimulation 1 minute on/4 minutes off. RESULTS: The total seizure rate decrement during follow-up was 41% (CI 25%-56%), with better seizure control for GTCS (IQR 19%-20%) and FIAS (IQR 0%-16%), with FAS being less responsive (IQR 67%-236%). No neuropsychological deterioration was observed. CONCLUSIONS: PHC DBS induced important antiseizure effects in patients with incapacitating FIAS and GTCS, most likely through blocking the propagation of hippocampal-onset seizures. The PHC target can be easily and safely approached due to positioning away from vascular structures, and there was no evidence of DBS-induced cognitive deterioration.

Stereotactic biopsy for intracranial space occupying lesions: Experience in a referral hospital in Mexico.

BACKGROUND: Stereotactic brain biopsy (SBB) is used for establishing the histological diagnosis of intracranial lesions that are not amenable for a direct surgical approach. OBJECTIVE: The objective of the study was to describe our experience having an evaluation of the biopsy sample by a neuropathologist during SBB. MATERIALS AND METHODS: Retrospective analysis of 140 consecutive patients who underwent SBB between 2014 and 2018 in whom trans-operatory analysis of the sample was performed. RESULTS: There were 56% men. The mean age was 45 years. Histological diagnosis was performed in 131 of 140 patients (94% overall diagnostic yield). The presurgical radiological diagnosis was correct in 39%. Neoplastic lesions were reported in 108 cases, and 32 were non-neoplastic. We performed craniotomy and resection after biopsy in 14%. We found complications in 6% of patients. CONCLUSIONS: SBB continues to be a safe, useful, and inexpensive procedure. The diagnostic performance of SBB increases when intraoperative cytological evaluation by a neuropathologist is included in the study.

ANTECEDENTES: la biopsia cerebral por estereotaxia (SBB) se utiliza para establecer el diagnóstico histológico de lesiones intracraneales que no son susceptibles de un abordaje quirúrgico directo. OBJETIVO: describir nuestra experiencia de tener una evaluación de la muestra de biopsia por un neuropatólogo durante el procedimiento. MATERIAL Y MÉTODOS: análisis retrospectivo de 140 pacientes consecutivos sometidos a SBB entre 2014-2018 en los que se realizó análisis transoperatorio de la muestra. RESULTADOS: El 56% fueron hombres. La edad promedio fue de 45 años. El diagnóstico histológico se realizó en 131 de 140 pacientes (rendimiento diagnóstico global del 94%). El diagnóstico radiológico prequirúrgico fue correcto solo en el 39%. Se identificaron lesiones neoplásicas en 108 casos, y en 32 se documentaron lesiones no neoplásicas. En el 14% de los casos se realizó posterior a la biospia craneotomía y resección de la lesión. Encontramos complicaciones en el 6% de los pacientes. CONCLUSIONES: SBB sigue siendo un procedimiento seguro, útil y económico. El rendimiento diagnóstico de SBB aumenta cuando se incluye la evaluación citológica intraoperatoria por un neuropatólogo.

Olfactory function in patients with temporal lobe epilepsy; correlation of functional magnetic resonance imaging for olfaction with the laterality of the epileptic focus.

The olfactory function shares the same cerebral structures as those involved in the origin and propagation of focal temporal lobe seizures. Likewise, functional magnetic resonance imaging (fMRI) allows the study of olfactory function. This suggests that by quantitatively studying the olfactory function with an olfactory paradigm through fMRI it is possible to identify the functional alteration produced by the epileptic focus. The objective of the present study was to assess the olfactory function in the side of the epileptic focus in patients with mesial temporal lobe epilepsy, using fMRI for smell, and propose a non-invasive diagnostic method for patients candidates to mesial temporal lobe epilepsy surgery. METHODS: Patients (n = 18) with clinical diagnosis of mesial temporal lobe epilepsy, refractory to pharmacological treatment: 7 patients (38.9%) with non-invasive studies consistent enough to submit them to anterior temporal lobectomy, and 11 (61.1%) patients where focal onset seizures were identified by stereoelectroencephalography (SEEG) on the left temporal lobe in 5 (27.8%) and in both temporal lobes in 2 (11.1%). Patients were evaluated using EEG, MRI, neuropsychological data, and fMRI with olfactory paradigm. Results of the fMRI were compared with the laterality of the epileptic focus determined by intracranial electroencephalogram recordings through stereotactically placed electrodes, and with post-surgical outcome at one year of follow-up. RESULTS: fMRI showed a lower olfactory activation in 81.8% concordant with unilateral onset seizures. There were significant differences of olfactory fMRI activation between epileptic and non-epileptic foci. CONCLUSION: Functional magnetic resonance imaging with an olfactory paradigm may be a non-invasive diagnostic tool to determine the laterality of seizure onset in the mesial temporal lobe.

Resection of meningiomas in a different location (sphenoid wing and tuberculum sellae) through a single craniotomy report of a case and review of the literature.

Meningiomas are the most frequent extra-axial tumors of the nervous system. Multiple meningiomas are defined as the presence of two or more lesions that appear simultaneously or not, in different intracranial location, without association to neurofibromatosis. Each lesion must be evaluated individually for treatment, which consists in microsurgical resection in most cases. A 59-year-old woman presented with neurological symptoms from different anatomical site. Two extra-axial tumors of different location, at right sphenoid wing and the other in the tuberculum sellae were identified. Microsurgical resection was decided in one-step surgery, using the same craniotomy for both lesions with complete resection.

Los meningiomas son los tumores extraaxiales más frecuentes del sistema nervioso. Los meningiomas múltiples o meningiomatosis (MM) se definen como la presencia de 2 o más lesiones que aparecen simultáneamente o no, en diferente localización intracraneal, sin asociación con neurofibromatosis. Cada lesión debe ser evaluada de manera individual para su tratamiento. Presentamos una paciente con meningiomatosis. La sintomatología era muy variada de localizaciones anatómicas diferentes. En los estudios de imagen, se identificaron tumores extra axiales de diferente localización, una lesión alar y otra del tubérculo sellar. Se decidió la resección microquirúrgica en un solo tiempo, mediante la misma craneotomía.

Specific movement and disability improvements in Burke-Fahn-Marsden Dystonia Rating Scale derived from pallidotomy in refractory patients to medical treatment.

BACKGROUND: Dystonia is a movement disorder associated with significant disability and is usually refractory to medical treatment. Pallidotomy may decrease dystonic movements. The aim of this study was to quantify movement and disability improvements through Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). METHODS: We carried out a longitudinal clinical study in patients with refractory primary and secondary dystonia, who underwent radiofrequency (RF) unilateral and bilateral lesions on the postero-ventro-lateral globus pallidus internus (GPi), evaluating the outcomes through BFMDRS and variables as age, time of evolution, etiology, body distribution, planned target coordinates, and lesion size, during a mean follow-up time of 35.67 months. RESULTS: Nine RF pallidotomies were performed on 6 patients, 7 right-sided and 2 left-sided; three patients were treated unilaterally for one occasion, while the others underwent 2 surgeries, including one staged bilateral procedure. Mean BFMDRS scores for movement were 38.5 preoperative and 25.5 postoperative, and for disability were 20.4 preoperative and 17.3 postoperative. We noticed improvement in movement (32.54%, p = 0.001) and disability (17.23%, p = 0.002). There was one right GPi and internal capsule (IC) infarction with contralateral hemiparesis as sequelae. CONCLUSIONS: RF pallidotomy is an effective and accessible procedure to reduce BFMDRS scores in refractory dystonia if patients are correctly selected by severity, evolution, and disability as determining factors.

Hemorrhagic stroke associated to COVID-19 infection in Mexico General Hospital.

INTRODUCCIÓN: en la actual pandemia de COVID-19, existe evidencia creciente que ha identificado el neurotropismo del virus SARS-CoV-2 y sus complicaciones neurológicas, incluida la enfermedad cerebrovascular isquémica y escasamente hemorragia cerebral (HC). OBJETIVO: describir las características clínicas, radiológicas, de laboratorio y pronósticas de los pacientes con HC asociada al SARS-CoV-2. MÉTODOS: se incluyeron pacientes consecutivos con prueba de PCR confirmatoria para infección por SARS-CoV-2 y HC. RESULTADOS: en un período de 90 días, en un centro de referencia COVID-19 en México, de 1108 pacientes con infección por SARS-CoV-2, se encontraron 4 pacientes (0.36%) con HC. Tenían una edad de 71(±12.2) años, 2 eran mujeres. Se encontró que dos tenían factores de riesgo cardiovascular previos. En dos casos se encontró el origen en el núcleo dentado mientras que los otros dos correspondieron al tálamo. Tres de los cuatro pacientes murieron. Postulamos que el descontrol hipertensivo, coagulopatía, trombocitopenia y la respuesta inmune inducida por el virus SARS-CoV-2 podrían desencadenar HC en un paciente con riesgo previo. CONCLUSIONES: la HC se asocia a la infección por SARS-CoV-2 con mal pronóstico cuando se presenta. Los equipos de neurocirugía deben estar preparados para el tratamiento oportuno de estos pacientes. INTRODUCTION: In the current COVID-19 pandemic, there is a growing body of evidence that has identified the neurotropism of the SARS-CoV-2 virus and its neurological complications, including cerebrovascular disease, focusing mainly in ischemic and scarcely about hemorrhagic stroke (HS). OBJECTIVE: The objective of the study was to describe clinical, radiological, laboratory tests, and prognostic characteristics of patients with SARS-CoV-2 associated HS. METHODS: Consecutive patients with a confirmatory PCR test for SARS-CoV-2 infection and a HS demonstrated by head CT were included in the study. RESULTS: Over a period of 90 days, in a COVID-19 reference center in Mexico, out of a total of 1108 patients with SARS-CoV-2 infection, it found 4 patients (0.36%) who meet criteria. They had an age of 71 (±12.2) years, 2 were women. It was found that two had prior cardiovascular risk factors. Two of the HS originated in the dentate nucleus while the other two corresponded to the thalamus. Three of the four patients died. We suggest that catastrophic uncontrolled blood pressure, coagulopathy, thrombocytopenia, and immune response induced by SARS-CoV-2 could in a specific patient trigger HS. CONCLUSIONS: HS is associated to SARS-CoV-2 infection with poor prognosis when it presented. Neurosurgery teams should prepare for the timely and appropriate treatment of this patients.

Centromedian Nucleus and Epilepsy.

SUMMARY: Centromedian thalamic nucleus is an intralaminar nucleus with vast connectivity to cerebral cortex and basal ganglia. It receives afferents from the brain stem through the central tegmental tract and is part of the diffuse thalamic projection system. Because the reticulothalamic system has been related to initiation and propagation of epileptic activity (centroencephalic theory of epilepsy), deep brain stimulation has been proposed to interfere with seizure genesis or propagation. Centromedian thalamic nucleus is a large nucleus laying nearby the anatomical references for stereotaxis and therefore a convenient surgical target to approach. Electrodes are implanted in the anterior ventral lateral part of the nucleus (parvocellular area), guided by intraoperative recruiting responses elicited by unilateral 6 to 8 Hz electrical stimulation delivered through the deep brain stimulation electrode. Therapeutic stimulation is delivered with the following parameters: 60 Hz, 450 µs, 3.0 V. Seizure control runs between 69% and 83% in different reports, decreasing mainly generalized seizures from the start, with significant improvement in neuropsychological performance. Significant decrease in seizure occurs from hours to days after the onset of deep brain stimulation. Some reports refer that seizure improvement may occur by the simple insertion of the deep brain stimulation electrodes, and therefore, it was used to treat refractory epileptic status.

Women in Neurosurgery: First Neurosurgeon in Latin America and Current Mexican Leaders.

BACKGROUND: History has taught us that Mexican culture has been largely supported by women, despite gender prejudice from the society. Neurosurgery has not been the exception. Therefore, we investigated the challenges and influence of female neurosurgeons in Mexico. METHODS: We conducted a review of the literature and an analysis of the internal database of the Mexican Society of Neurological Surgery focusing on 3 topics: 1) the historical presence of women and gender inequality in Mexico; 2) the life and legacy of the woman who became the first neurosurgeon in Mexico and in Latin America; and 3) the participation of women in neurosurgery in the past 3 decades. RESULTS: In Latin America, the first woman in neurosurgery was María Cristina García-Sancho, who completed her neurosurgical training in 1951. Currently, women represent 6.2% of the total members of the Mexican Society of Neurological Surgery (MSNS). This percentage is still low, although data collected in this study suggest that it might increase in the next few years because 16.7% of Board Directors of the MSNS are women, the next elected president is a female neurosurgeon, and 14.5% of neurosurgery residents are women. CONCLUSIONS: Although a steady increase has occurred of women in neurosurgery in Mexico, there is still work to do, especially to overcome the barriers related to the old assumptions of the cultural and social roles of women.

Radiofrequency ablation of the centromedian thalamic nucleus in the treatment of drug-resistant epilepsy.

OBJECTIVE: To determine the usefulness and efficacy of radiofrequency ablations (RFA) of the Centromedian thalamic nucleus (CMN) to control primarily generalized or multifocal seizures in refractory epilepsy. METHODS: Six patients with clinical diagnosis of multifocal or primarily generalized drug-resistant epilepsy were included. Bilateral RFA of the CMN was performed through a monopolar 1.8 mm. tip electrode with a temperature of 80 °C during 90 seconds. Patients were followed in every 3 months visit for 20 to 36 months and kept a monthly seizure count calendar. We also compared maximal paroxysmal electroencephalogram (EEG) activity and neuropsychological evaluation pre and 6 months postoperatively. RESULTS: A significant reduction in the number of generalized seizures was observed in all subjects in the range of 79-98%, starting the first post-operative month. Although focal aware seizures remained unchanged throughout follow-up, there was an important reduction on paroxysmal activity between the pre and postoperative EEG. No major changes on cognitive status were detected. There was post-operative dysphagia and odynophagia lasting one week and there was no mortality in this group of patients. CONCLUSION: Preliminary results of CMN RFA suggest safety and a trend toward reduction of some seizure types, it may reduce the seizure frequency like other palliative procedures since the first post-operative month, but a larger, controlled study would be needed to establish the value of this therapy.

Dysembryoplastic neuroepithelial tumor and temporal arachnoid cyst on a child with epilepsy. Which one to operate? Case report and literature review.

A 6 year-old male, with seizures characterized by abnormal epigastric sensation, behavioral arrest, upper extremities search automatisms and secondary tonic-clonic generalization. Magnetic resonance imaging showed a hypointense cystic extra-axial image with an increase in the thickness of the convolutions in the first and second gyri of the right frontal lobe. It was decided to resect the frontal lesion with transoperative motor mapping. Morphological and immunohistochemical findings corresponded to dysembryoplastic neuroepithelial tumor with focal cortical dysplasia. Adequate semiology, analysis of the electroencephalogram, and imaging studies allowed treating adequately the cortical dysplasia. At present, the patient is seizure-free without medication (Engel IA).

Niño de 6 años con crisis caracterizadas por sensación epigástrica, arresto conductual, automatismos de búsqueda y generalización tónico-clónica secundaria. La resonancia magnética mostró una imagen extraaxial quística y un aumento del grosor de las circunvoluciones del primer y segundo giros del lóbulo frontal derecho. Se decidió resecar primero la lesión frontal con guía por mapeo transcortical intraoperatorio. Los hallazgos morfológicos e inmunohistoquímicos mostraron un tumor neuroepitelial disembrioplásico con displasia cortical focal. La semiología, el análisis del electroencefalograma y la imagen permitieron orientar el tratamiento. Actualmente el paciente está libre de crisis y sin medicamentos (Engel IA).

Long-Term Improvement of Parkinson Disease Motor Symptoms Derived From Lesions of Prelemniscal Fiber Tract Components.

BACKGROUND: Prelemniscal radiations (Raprl) are composed of different fiber tracts, connecting the brain stem and cerebellum with basal ganglia and cerebral cortex. In Parkinson disease (PD), lesions in Raprl induce improvement of tremor, rigidity, and bradykinesia in some patients, while others show improvement of only 1 or 2 symptoms, suggesting different fiber tracts mediate different symptoms. OBJECTIVE: To search for correlations between improvements of specific symptoms with surgical lesions of specific fiber tract components of Raprl in patients with PD. METHODS: A total of 10 patients were treated with unilateral radiofrequency lesions directed to Raprl. The improvement for tremor, rigidity, bradykinesia, posture, and gait was evaluated at 24 to 33 mo after operation through the Unified Parkinson's Disease Rating Scale (UPDRS) score, and the precise location and extension of lesions through structural magnetic resonance imaging and probabilistic tractography at 6 to 8 mo postsurgery. Correlation between percentage of fiber tract involvement and percentage of UPDRS-III score improvement was evaluated through Spearman's correlation coefficient. RESULTS: Group average improvement was 86% for tremor, 62% for rigidity, 56% for bradykinesia, and 45% for gait and posture. Improvement in global UPDRS score correlated with extent of lesions in fibers connecting with contralateral cerebellar cortex and improvement of posture and gait with fibers connecting with contralateral deep cerebellar nuclei. Lesion of fibers connecting the globus pallidum with pedunculopontine nucleus induced improvement of gait and posture over other symptoms. CONCLUSION: Partial lesion of Raprl fibers resulted in symptom improvement at 2-yr follow-up. Lesions of selective fiber components may result in selective improvement of specific symptoms.

Hemifacial Spasm Associated with Compression of the Facial Colliculus by a Choroid Plexus Papilloma of the Fourth Ventricle.

BACKGROUND: Hemifacial spasm is an involuntary condition that involves muscles innervated by the ipsilateral facial nerve. There are secondary causes of hemifacial spasm that can produce a typical presentation of symptoms. Extrinsic compression of the facial colliculus at the floor of the fourth ventricle is responsible for <0.6% of the causes of secondary hemifacial spasm, as the cases with this origin reported in the literature are rare. CASE REPORTS: We present the case of a 43-year-old female with hemifacial spasm of typical characteristics 6 months after onset. Upon clinical examination, a severe contraction of the orbicularis oculi, orbicularis oris, and superficial muscles of the neck displaying 50 crisis per hour was revealed. Brain magnetic resonance imaging showed absence of the facial nerve vascular loop in the cisternal portion, with evidence of an intraventricular tumor in relation with the medial portion of the fourth ventricle at the facial colliculus level, indicating a secondary origin of hemifacial spasm. Preoperative electromyography demonstrated irritative electric activity in the muscular branches of the facial nerve. A telovelar approach was performed to the fourth ventricle with intraoperative electrophysiology monitoring, with immediate resolution of the irritative activity after complete tumor resection. The result of the histopathologic study was a choroid plexus papilloma. CONCLUSION: Fourth ventricle tumors with extrinsic compression of the facial colliculus represent <0.6% of the causes of hemifacial spasm. Its relationship with choroid plexuses papilloma is being described as the first case reported in the literature. Clinical correlation, imaging, and intraoperative findings in conjunction with intraoperative electrophysiology recordings allow to predict the resolution of symptoms after resecting the lesion.

Radiofrequency Ablation of Prelemniscal Radiations for the Treatment of Non-Parkinsonian Tremor.

OBJECTIVE: Previous reports proposed prelemniscal radiations (Raprl) as a target to treat motor symptoms of Parkinson's disease, and this was found particularly effective to control rest and postural tremor. However, tremor of other etiologies has been seldom treated with deep brain stimulation or ablation in this target. We present a series of such cases successfully treated by Raprl radiofrequency (RF) lesions. MATERIAL AND METHODS: Six patients with predominant unilateral tremor on the right arm: 4 intention, 1 cerebellar and 1 rubral tremor, incapacitating in spite of at least 2 regimes of medical treatment at maximal tolerated doses, were operated under local anesthesia. RF lesions were performed in Raprl contralateral to most prominent symptoms. Patients had monthly evaluation of tremor severity through the Fahn-Tolosa-Marin Tremor Rating Scale and disability through the Tremor Disability Scale along a 1-year follow-up. RESULTS: In 4/6 patients tremor was stopped by the simple insertion of an RF electrode in Raprl; in the other 2 cases, stimulation through the RF electrode at 100 Hz, with 100 µs and 1.0-1.5 V, stopped the tremor without side effects. Tremor disappeared in all cases immediately after surgery and partially reappeared in 2 cases with an amplitude about 20% of the preoperative condition. RF lesions in postoperative MRI ranked from 1.8 to 2.6 mm in diameter. CONCLUSIONS: RF lesioning in Raprl is a simple, highly effective, inexpensive way to treat tremor of different etiologies.