Frontal aslant tract: Anatomy and tractography description in the Mexican population.

Background: The aim of the study was to describe the origin, course, and termination of frontal aslant tract (FAT) in the Mexican population of neurosurgical referral centers. Methods: From January 2018 to May 2019, we analyzed 50 magnetic resonance imaging (MRI) studies in diffusion tensor imaging sequences of patients of the National Institute of Neurology and Neurosurgery "Manuel Velasco Suárez." Five brains were fixed by the Klingler method and dissected in the neurosurgery laboratory of the Hospital Civil de Guadalajara to identify the origin, trajectory, and ending of the FAT. Results: FAT was identified in 100% of the MRI and brain dissections. The origin of the FAT was observed in 63% from the supplementary premotor area, 24% from the supplementary motor area, and 13% in both areas. Its ending was observed in the pars opercularis in 81%, pars triangularis in 9%, and in both pars opercularis and ventral premotor area in 10% in the magnetic resonance images, with a left side predominance. In the hemispheres dissections, the origin of FAT was identified in 60% from the supplementary premotor area, 20% from the supplementary motor area, and 20% in both areas. Its ending was observed in the pars opercularis in 80% and the pars triangularis in 20%. It was not identified as an individual fascicle connected with the contralateral FAT. Conclusion: In the Mexican population, FAT has a left predominance; it is originated more frequently in the supplementary premotor area, passes dorsal to the superior longitudinal fascicle II and the superior periinsular sulcus, and ends more commonly in the pars opercularis.

Awake Surgery With Visual Pathway Mapping in Low Grade Glioma Surgery.

The visual pathway and its defects have been thoroughly studied in clinical correlation to temporal lobe lesions related to epilepsy and traumatic lesions. Nevertheless, its clinical correlation and other decision-making have not been addressed regarding neoplastic lesions. We present a case report of a 28-year-old man with a one-year history of generalized seizures and left superior homonymous quadrantanopia, with no other neurological disturbance on physical examination. According to diffusion tensor imaging tractography, MRI demonstrated a non-enhancing, right temporal lesion disrupting the visual pathway. An awake surgery with direct cortical electrostimulation of visual pathways was performed with subtotal resection of the tumor to preserve visual function, confirmed with postoperative MRI. Histopathological studies revealed a fibrillary astrocytoma. Surgical technique aided with intraoperative cortical and subcortical stimulation involving low-grade gliomas in eloquent areas is an exceptionally suitable procedure for complex cases where the visual pathway is compromised. Our objective is to describe how intraoperative mapping of visual function is performed in our institution and to comment on the relevant technical nuances, which can serve as a practical guideline for young neurosurgeons, as no previous cases have been reported in our country.

Analysis of Intraoperative Seizures During Bipolar Brain Mapping in Eloquent Areas: Intraoperative Seizures in brain mapping.

OBJECTIVES: Awake Craniotomy (AC) is a very well described technique that is performed to make an adequate tumor resection preserving the functionality of the patient. Intraoperative Seizures (IS) are reported as a failure of such procedure. We analyze the incidence and risk factor during AC. METHODS: We made a review of the database of the National Institute of Neurology and Neurosurgery between January 2017 and May 2019 for intrinsic tumors located in eloquent areas of the brain. An analysis of ISconcerning the clinical history, clinical presentation, imaging techniques, histological findings and surgical technique was made. The factors associated with Mapping Failure (MF) were also evaluated. RESULTS: 45 patients were included of whom 7 patients (15.6%) developed IS after cortical-subcortical stimulation, 5 presented partial motor seizures (11.1%) and 2 experimented generalized secondary seizures (4.5%). Of the patients that had a MF, one patient (14%) was due to generalized tonic-clonic seizures which couldn't be managed by cold saline irrigation and administration of anti-seizures drugs and was then converted to a general anesthetic technique. We observed that the patients that had a bigger tumoral volume (112.2 cm3 85.3, P = 0,07) had a bigger positive relation in presenting IS, having a peak sensibility and specificity above 70 cc (ROC). CONCLUSIONS: In our analysis IS are more common in patients with high presurgical tumor volume. Even though the majority of the patients that presented IS didn't develop MF, it is important to acknowledge that the multidisciplinary group in the operating room must be prepared to detect these complications, treat them promptly and avoid MF.

Response to SARS-CoV-2 Pandemic in a Non-COVID-19 Designated Latin-American Neurosurgery Department.

Background: Mexico declared the first case of novel coronavirus disease (COVID-19) in February 2020. At the time we write this article, our country is facing a community spread phase, expecting a rapid increase in the number of cases and fatalities. The Fray Antonio Alcalde Civil Hospital of Guadalajara has been declared a non-COVID-19 hospital with the mission of providing care to patients already registered and also those transferred from neurosurgical departments of neighboring centers, which have been converted into COVID-19 only hospitals. Methods: An organized response regarding personnel, surgical case selection, operating room behavior, and facility reorganization were designed to prevent an internal coronavirus outbreak in the neurosurgery department at the Fray Antonio Alcalde Civil Hospital of Guadalajara. Results: Distancing actions by the staff and residents, including ward case discussions, neurosurgery rounds, and classes, will be carried out virtually. We classified neurosurgical patients into 4 groups depending on whether their condition demands care in 0-6 hours, 6-48 hours, 48 hours to 14 days, and >14 days. Subsequently, a questionnaire with epidemiologic, radiologic, clinical, and serologic criteria will be applied to determine the risk of COVID-19 infection to define to which area they are going to be transferred according to the different risk zones in our facility. Conclusions: Despite not being a COVID-19 center, we consider all patients at the neurosurgical ward and staff members as asymptomatic carriers or infected in the preclinical period. Specific measures must be taken to ensure the safety and care of neurosurgical patients and medical staff during the community spread phase.

Awake surgery with cortical-subcortical mapping in diffuse gliomas adjacent to central lobe. Report of two cases and literature review.

INTRODUCTION: Diffuse gliomas are brain neoplasms with an infiltrative growing pattern to cortical and subcortical structures, frequently adjacent to eloquent areas; direct cortical and subcortical stimulation in awake craniotomy is a useful tool to achieve a gross total resection with the least neurological deficit. PRESENTATION OF CASES: A 24 years old male presented with tonic-clonic seizures. The magnetic resonance imaging (MRI) showed a left parietal glioma. Awake craniotomy was performed using neuronavigation system and brain mapping with cortical and subcortical stimulation. Functional areas were found at the rostral margin of the tumor; however, the rest of the tumor was almost totally resected. Patient was discharged without neurological deficit. A 29 years old male presented in two occasions generalized tonic-clonic seizures, with right hemiparesis. The MRI showed a left parietal glioma. Awake craniotomy was performed using neuronavigation system and brain mapping with cortical and subcortical stimulation, achieving a gross total resection. Patient was discharged without neurological deficit. CONCLUSIONS: Awake craniotomy with brain mapping by cortical and subcortical stimulation and neuronavigation, are the best assets to treat diffuse gliomas and achieve a gross total resection, ensuring the major disease-free interval and preserving the function of eloquent areas.

INTRODUCCIÓN: Los gliomas difusos son neoplasias cerebrales con un patrón de crecimiento infiltrativo, frecuentemente adyacentes a áreas elocuentes. El mapeo cerebral con estimulación cortico-subcortical con el paciente despierto es una herramienta útil para lograr la mayor resección con el menor déficit posoperatorio. PRESENTACIÓN DE CASOS: Varón de 24 años con crisis tónico-clónicas. La resonancia magnética (RM) mostró un glioma parietal izquierdo. Se realizó cirugía con el paciente despierto y mapeo cerebral por estimulación cortical y subcortical directa. Se obtuvo una resección casi total, ya que se encontraron áreas fucionales en el borde rostral del tumor. El paciente egresó sin déficit neurológico. Varón de 29 años que presenta crisis tónico-clónicas generalizadas, acompañadas de hemiparesia derecha. La RM reportó un glioma parietal izquierdo. Se realizó cirugía con el paciente despierto y mapeo cerebral por estimulación cortical y subcortical directa. Se logró una resección total y el paciente egresó sin déficit. CONCLUSIONES: La cirugía con el paciente despierto con mapeo por estimulación directa y neuronavegación es la mejor opción en el tratamiento de los gliomas difusos, para lograr una resección máxima tumoral asegurando un mayor tiempo libre de enfermedad y la conservación de la función de áreas elocuentes.

Evaluation of blood pressure measurements in first ambulatory neurological consultations: A missed part of the physical examination? / Evaluación de la medición de la presión arterial en primeras consultas neurológicas ambulatorias: ¿una parte olvidada del examen físico?

Objective: To obtain a blood pressure reading is mandatory during either the general or specialized physical examination. This study describes factors associated with the accomplishment of blood pressure measurement in the first neurological consultation. Methods: We studied first ambulatory neurology consultations in a Mexican referral hospital. Demographic characteristics, diagnostic category of referral, final diagnosis and data on physical examination were collected to establish a logistic regression analysis in order to identify factors associated with the accomplishment of blood pressure measurement. Results: Over 8 months 778 outpatients were studied. The most frequent diagnoses for first consultation were headache (26%), epilepsy (14%) and stroke (13%). Only in 39% (n = 301) of the outpatients blood pressure was registered, among them, 30% had normal blood pressure, 43% had 121-139/81-89mmHg, 20% had 140-159/90-99mmHg and 7% had ≥ 160/100mmHg. The independent factors that favored the practice of BP determination in multivariable analysis were >65 years of age (odds ratio: 2.26; 95% confidence interval: 1.52-3.36) and headache complaint (odds ratio: 1.81, 95% confidence interval: 1.30-2.53). Notably, only 43% of patients with stroke had blood pressure registration, even when these stroke patients had blood pressure readings, they had higher blood pressure than with other diagnoses (p< 0.05). Conclusion: Blood pressure registration was frequently omitted from the first neurological consultation, particularly in outpatients who might need it the most.

Objetivo: La medición de la presión arterial es mandatoria durante el examen físico general o especializado. Este estudio describe factores asociados al cumplimiento de la medición de la presión arterial en la primera consulta neurológica. Métodos: Realizamos un estudio sobre consultas neurológicas ambulatorias en un hospital de referencia mexicano. Se recolectaron características demográficas, categoría diagnóstica de referencia, diagnóstico final y datos sobre el examen físico para construir un análisis de regresión logística con el objetivo de identificar factores asociados con el cumplimiento de la medición de la presión arterial. Resultados: Durante 8 meses estudiamos a 778 pacientes. Los diagnósticos de envío más frecuentes fueron cefalea (26%), epilepsia (14%) y enfermedad cerebrovascular (13%). Solo en el 39% (n = 301) de los pacientes se midió la presión arterial y, de entre ellos, el 30% presentaron presión arterial normal, el 43% 121-139/81-89mmHg, el 20% 140-159/90-99mmHg y el 7% ≥ 160/100 mmHg. En un análisis multivariable, la edad > 65 años (razón de momios: 2.26, intervalo de confianza del 95%: 1.52-3.36) y cefalea como motivo de consulta (razón de momios: 1.81, intervalo de confianza del 95%: 1.30-2.53) fueron los factores independientes asociados al registro de la presión arterial. De manera notable, solo al 43% de los pacientes con enfermedad cerebrovascular se les había registrado la presión sanguínea; estos pacientes la tenían más elevada que los pacientes con otros diagnósticos (p <0.05). Conclusión: En este estudio con frecuencia se omitió el registro de la presión arterial en la primera consulta neurológica, especialmente en pacientes que podrían necesitarlo más.

Evaluation of blood pressure measurements in first ambulatory neurological consultations: a missed part of the physical examination?

OBJECTIVE: To obtain a blood pressure reading is mandatory during either the general or specialized physical examination. This study describes factors associated with the accomplishment of blood pressure measurement in the first neurological consultation. METHODS: We studied first ambulatory neurology consultations in a Mexican referral hospital. Demographic characteristics, diagnostic category of referral, final diagnosis and data on physical examination were collected to establish a logistic regression analysis in order to identify factors associated with the accomplishment of blood pressure measurement. RESULTS: Over 8 months 778 outpatients were studied. The most frequent diagnoses for first consultation were headache (26%), epilepsy (14%) and stroke (13%). Only in 39% (n=301) of the outpatients blood pressure was registered, among them, 30% had normal blood pressure, 43% had 121-139/81-89 mmHg, 20% had 140-159/90-99 mmHg and 7% had ≥ 160/100 mmHg. The independent factors that favored the practice of BP determination in multivariable analysis were >65 years of age (odds ratio: 2.26; 95% confidence interval: 1.52-3.36) and headache complaint (odds ratio: 1.81, 95% confidence interval: 1.30-2.53). Notably, only 43% of patients with stroke had blood pressure registration, even when these stroke patients had blood pressure readings, they had higher blood pressure than with other diagnoses (p<0.05). CONCLUSION: Blood pressure registration was frequently omitted from the first neurological consultation, particularly in outpatients who might need it the most.