Delimitation of the risk area of the vertebral artery during the paramedian suboccipital approach.

OBJECTIVE: The V3 segment of the vertebral artery (V3-VA) is at risk during diverse approaches to the craniovertebral junction. Our objective is to present a system of anatomic and topographic landmarks to identify the V3-VA during the paramedian suboccipital approach (PMSOA) with the help of minimal or basic tools. MATERIAL AND METHODS: The first was a retrospective analysis of the angiotomography (CTA) of 50 patients over 18-years old, and 9 anatomical dissections. A series of lines were defined between the different bony landmarks. Within this lines the risk area of the vertebral artery (RAsV3-VA) and the risk point of the vertebral artery (RPsV3-VA) were defined. The second stage was a prospective study, where the previously defined measurements were carried out by using neuronavigation in 10 patients (20 sides) operated with the PMSO approach in order to confirm the presence of the V3 segment in the RAsV3-VA and RPsV3-VA. RESULTS: In the first stage, the V3 segment was found in the middle third of the X line in 96,6% of the cases. The distance between the inion and the UCP (percentile 5) was 20 mm and to the LCP (percentile 95) was 40 mm. In the range between the UCP and the LCP, in the middle third of the inion-mastoid line (RAsV3-VA), we found 90% of the V3-VA. The measurements taken during the second stage revealed that the artery was in the middle third of the X line in 97% of the cases. 85% of the patients presented the total of the V3s-VA on the RAsV3-VA and in 85% there was a direct relationship with the V3 segment and the RPV3s-VA. CONCLUSION: We propose an easy-to-implement system to delimit the risk area of the V3-VA during the PMSOA. We believe that these landmarks provide a practical, reliable, costless and useful tool that could decrease the risk of lesion of the V3-VA during this approach without the need of using.

Experience in awake glioma surgery in a South American center. Correlation between intraoperative evaluation, extent of resection and functional outcomes.

Introduction: Gliomas are the second most frequent primary brain tumors. Surgical resection remains a crucial part of treatment, as well as maximum preservation of neurological function. For this reason awake surgery has an important role.The objectives of this article are to present our experience with awake surgery for gliomas in a South American center and to analyze how intraoperative functional findings may influence the extent of resection and neurological outcomes. Materials and methods: Retrospective single center study of a cohort of adult patients undergoing awake surgery for brain glioma, by the same neurosurgeon, between 2012 and 2022 in the city of Buenos Aires, Argentina. Results: A total of 71 patients were included (mean age 34 years, 62% males). Seventy seven percent of tumors were low grade, with average extent of resection reaching 94% of preoperative volumetric assessment. At six months follow up, 81.7% of patients presented no motor or language deficit.Further analysis showed that having a positive mapping did not have a negative impact in the extent of resection, but was associated with short term postoperative motor and language deficits, among other variables, with later improvement. Conclusion: Awake surgery for gliomas is a safe procedure, with the proper training. In this study it was observed that guiding the resection by negative mapping did not worsen the results and that positive subcortical mapping correlated with short term postoperative neurological deficits with posterior improvement within six months in most cases.

Transoperative Magnetic Resonance Imaging in awake glioma surgery: Experience in a Latin American tertiary-level center.

OBJECTIVE: Analyze the usefulness, efficacy, and safety of transoperative Magnetic Resonance Imaging in glioma surgery in awake patients. MATERIALS AND METHODS: Retrospective, single-center, analytical study of a cohort of patients who underwent awake surgery for gliomas by the same surgeon in a third-level Argentine center, in the period between 2012-2022. Only patients with pathology-confirmed gliomas, with 6-month follow-up, who had pre and postoperative volumetric MRI, were included in this sample. Subsequently, we analyzed which patients received surgery with the tMRI protocol and the results using multivariate regression analysis. RESULTS: A total of 71 patients were included. A tMRI study was performed on 22 (31%) of these patients. The use of tMRI increased the percentage of resection by 20% (p = 0.03), thereby increasing the possibility of gross-total resection. However, using tMRI significantly extended surgical time by 84 minutes (p < 0.001). In 55% of the patients in whom tMRI was performed, the resection was continued after it. The use of tMRI did not increase the rate of infections or the development of surgically associated neurological deficits in the long term, despite the fact that 47% of the patients showed the development of a new deficit or worsening of a previous one during the intraoperative period. CONCLUSION: The use of tMRI in awake glioma surgery proved to be a safe tool that contributes to increasing the degree of tumor resection, compared to the use of neurophysiological mapping and neuronavigation, at the expense of increased surgical times and costs. We consider tMRI in awake glioma surgery should be used in properly selected cases.

Intradural extramedullary tumors. Retrospective cohort study assessing prognostic factors for functional outcome in adult patients / Tumores intradurales-extramedulares. Estudio retrospectivo de cohorte valorando factores predictores de «outcome» en pacientes adultos

Objective The purpose of this study is to analyze a series of patients with intradural extramedullary tumors (IDEM) and assess factors that may modify or determine the final long term outcome and management. Materials and methods Single Center, retrospective study of a series of surgical patients with IDEM lesions from our Institution operated between 2010 and 2021. Patients with less than 6 months of follow up were excluded. Several preoperative demographics, clinical, imaging and surgical features, as well as histopathology, recurrence and adjuvancy were assessed. Patients’ final clinical outcome was categorized using the McCormick scale. Results A total of 203 patients with a mean follow-up of 30.50 months (range 6–130) were included. 57.64% of the analyzed population was female and the mean age was 50.51 years. The most frequent location of the tumors was dorsal (34.98%) followed by the lumbar region (32.02%). Total resection was achieved in 84.24% of cases, and the most frequent histopathology was Schwannoma (36.45%), followed by Meningioma (30.05%). Pain was the most usual initial symptom (63.05%). In our analysis, functional outcome after surgery was associated with statistical significance with preoperative McCormick grade, tumor type, EOR and postoperative complications such as hematoma and sphincter involvement. Conclusion The management of these lesions depends on many factors. It is worthy of mention that clinical presentation, EOR, histopathology and postoperative complications have shown significant prognostic value for the final outcome. Early treatment with the intention of achieving GTR when possible, using carefully tailored approaches, should be considered before the onset of significant symptoms (AU)

Objetivo Analizar una serie de pacientes con tumores intradurales extramedulares y evaluar factores que pueden modificar o determinar el resultado final y el manejo a largo plazo. Materiales y métodos Estudio monocéntrico, retrospectivo de una cohorte de pacientes quirúrgicos con lesiones intradurales extramedulares (IDEM) operados entre 2010 y 2021 y un mínimo de seis meses de seguimiento. Se evaluaron características clínicas, de imagen y quirúrgicas, histopatología, recurrencia y adyuvancia. El resultado clínico final de los pacientes se categorizó utilizando la escala de McCormick. Resultados Se incluyeron un total de 203 pacientes con un seguimiento medio de 30,50 meses (rango 6-130). De la población analizada, 57,64% era del sexo femenino y la edad media fue de 50,51 años. La localización más frecuente de los tumores fue dorsal (34,98%) seguida de la región lumbar (32,02%). La resección total se logró en 84,24% de los casos, y la histopatología más frecuente fue el schwannoma (36,45%), seguido del meningioma (30,05%). El dolor fue el síntoma inicial más habitual (63,05%). En nuestro análisis, el resultado funcional posoperatorio se asoció con significancia estadística con el grado de McCormick preoperatorio, la histopatología, el grado de resección y las complicaciones posoperatorias como el hematoma y la afectación esfinteriana. Conclusión El manejo de estas lesiones depende de muchos factores. Cabe mencionar que la presentación clínica, el grado de resección, la histopatología y las complicaciones posoperatorias han mostrado un importante valor pronóstico para el desenlace. Se debe considerar el tratamiento temprano con la intención de lograr resección total cuando sea posible, mediante abordajes cuidadosamente adaptados, antes de la aparición de síntomas significativos (AU)

Intradural extramedullary tumors. Retrospective cohort study assessing prognostic factors for functional outcome in adult patients.

OBJECTIVE: The purpose of this study is to analyze a series of patients with intradural extramedullary tumors (IDEM) and assess factors that may modify or determine the final long term outcome and management. MATERIALS AND METHODS: Single Center, retrospective study of a series of surgical patients with IDEM lesions from our Institution operated between 2010 and 2021. Patients with less than 6 months of follow up were excluded. Several preoperative demographics, clinical, imaging and surgical features, as well as histopathology, recurrence and adjuvancy were assessed. Patients' final clinical outcome was categorized using the McCormick scale. RESULTS: A total of 203 patients with a mean follow-up of 30.50 months (range 6-130) were included. 57.64% of the analyzed population was female and the mean age was 50.51 years. The most frequent location of the tumors was dorsal (34.98%) followed by the lumbar region (32.02%). Total resection was achieved in 84.24% of cases, and the most frequent histopathology was Schwannoma (36.45%), followed by Meningioma (30.05%). Pain was the most usual initial symptom (63.05%). In our analysis, functional outcome after surgery was associated with statistical significance with preoperative McCormick grade, tumor type, EOR and postoperative complications such as hematoma and sphincter involvement. CONCLUSION: The management of these lesions depends on many factors. It is worthy of mention that clinical presentation, EOR, histopathology and postoperative complications have shown significant prognostic value for the final outcome. Early treatment with the intention of achieving GTR when possible, using carefully tailored approaches, should be considered before the onset of significant symptoms.

[Endoscopic vs. microscopic techniques for the treatment of trigeminal neuralgia. Our experience at an Argentine care center]. / Descompresión microvascular endoscópica versus microscópica en neuralgia trigeminal en un Centro argentino.

INTRODUCTION: Trigeminal neuralgia is a highly invalidating pathology, whose natural course has been modified thanks to decompressive microvascular surgery. The intervention can be carried out either with a microscope or via an endoscopic technique. Our goal was to compare these two techniques for the treatment of this complex pathology. METHODS: Retrospective, analytical study of a cohort of patients treated by a single surgeon at our institution, in the period between 2015 and 2021. RESULTS: We identified 31 patients and divided them into two groups: 15 (49%) treated using the microscopic technique (group M), and 16 (51%) exclusively via an endoscopic one (group E). Differences were observed between the means of the size of the craniectomy in group M (3.7 cm) compared to group E (2.5 cm); The mean length of hospital stay for patients in group E was shorter (4.46 days compared to that of patients in group M, whose hospital stay averaged 2.43 days). There were no differences between the two groups regarding the length of the procedure. In both groups, the predominant compression was due to the superior cerebellar artery (SCA). Pain outcomes were equivalent, with every patient in both groups having an improved postoperative Barrow Neurological Institute Pain Intensity Score (BNI). DISCUSSION: Endoscopic microvascular decompression is an attractive option for the resolution of neurovascular conflict as it provides functional results similar to the microscope technique, without requiring an extensive craniectomy and associated to shorter in-hospital stay, which is beneficial for both the patient and the institution.

Introducción: La descompresión microvascular (DMV) en la neuralgia trigeminal es una técnica quirúrgica cuyo objetivo es revertir la compresión a la que se ve sometido un nervio por una estructura vascular. El objetivo de este estudio fue realizar una comparación directa entre la descompresión microvascular endoscópica (DMV-E) y la misma a través del uso del microscopio (DMV-M) en el tratamiento de la neuralgia del trigémino. Métodos: Se realizó un estudio de cohorte retrospectivo de pacientes operados de neuralgia de trigémino, por un mismo cirujano, entre 2015 y 2021 en nuestra institución, tanto por técnica microquirúrgica como endoscópica. Resultados: Se obtuvieron un total de 31 pacientes divididos en dos grupos: Grupo M correspondiente a 15 (49%) pacientes abordados con técnica microscópica y Grupo E, con 16 (51%) pacientes intervenidos con técnica endoscópica. Se identificaron diferencias en el tamaño de la craniectomía, más pequeña en el grupo E (2.50 cm vs 3.70 cm grupo M); y en el tiempo de internación, de 2.43 días en el grupo E vs. 4.46 días en el grupo M. El tiempo de cirugía fue similar para ambas técnicas quirúrgicas La principal compresión fue dada por la arteria cerebelosa superior (ACS) en ambos grupos. Todos los pacientes presentaron mejoría del Barrow Neurological Institute Pain Intensity Score (BNI) en el postoperatorio en ambos grupos. Discusión: La DMV-E constituye una alternativa quirúrgica interesante a la ya conocida DMV-M para el tratamiento de la neuralgia trigeminal, por requerir menores dimensiones en la incisión cutánea y tamaño de la craniectomía, acortando el tiempo de internación, lo cual no solo implica un beneficio para el paciente, sino que también representa menor costo de internación.

Descompresión microvascular endoscópica versus microscópica en neuralgia trigeminal en un centro Argentino / Endoscopic vs. microscopic techniques for the treatment of trigeminal neuralgia. Our experience at an Argentine care center

Resumen Introducción: La descompresión microvascular (DMV) en la neuralgia trigeminal es una técnica quirúrgica cuyo objetivo es revertir la compresión a la que se ve someti do un nervio por una estructura vascular. El objetivo de este estudio fue realizar una comparación directa entre la descompresión microvascular endoscópica (DMV-E) y la misma a través del uso del microscopio (DMV-M) en el tratamiento de la neuralgia del trigémino. Métodos: Se realizó un estudio de cohorte retrospec tivo de pacientes operados de neuralgia de trigémino, por un mismo cirujano, entre 2015 y 2021 en nuestra institución, tanto por técnica microquirúrgica como endoscópica. Resultados: Se obtuvieron un total de 31 pacientes divididos en dos grupos: Grupo M correspondiente a 15 (49%) pacientes abordados con técnica microscópica y Grupo E, con 16 (51%) pacientes intervenidos con técnica endoscópica. Se identificaron diferencias en el tamaño de la cra niectomía, más pequeña en el grupo E (2.50 cm vs 3.70 cm grupo M); y en el tiempo de internación, de 2.43 días en el grupo E vs. 4.46 días en el grupo M. El tiempo de cirugía fue similar para ambas técnicas quirúrgicas La principal compresión fue dada por la arteria ce rebelosa superior (ACS) en ambos grupos. Todos los pacientes presentaron mejoría del Barrow Neurological Institute Pain Intensity Score (BNI) en el postoperatorio en ambos grupos. Discusión: La DMV-E constituye una alternativa qui rúrgica interesante a la ya conocida DMV-M para el tratamiento de la neuralgia trigeminal, por requerir menores dimensiones en la incisión cutánea y tamaño de la craniectomía, acortando el tiempo de internación, lo cual no solo implica un beneficio para el paciente, sino que también representa menor costo de internación.

Abstract Introduction: Trigeminal neuralgia is a highly invali dating pathology, whose natural course has been modi fied thanks to decompressive microvascular surgery. The intervention can be carried out either with a microscope or via an endoscopic technique. Our goal was to compare these two techniques for the treatment of this complex pathology. Methods: Retrospective, analytical study of a cohort of patients treated by a single surgeon at our institution, in the period between 2015 and 2021. Results: We identified 31 patients and divided them into two groups: 15 (49%) treated using the microscopic technique (group M), and 16 (51%) exclusively via an endoscopic one (group E). Differences were observed between the means of the size of the craniectomy in group M (3.7 cm) compared to group E (2.5 cm); The mean length of hospital stay for patients in group E was shorter (4.46 days compared to that of patients in group M, whose hospital stay averaged 2.43 days). There were no differences between the two groups regarding the length of the procedure. In both groups, the predomi nant compression was due to the superior cerebellar artery (SCA). Pain outcomes were equivalent, with every patient in both groups having an improved postoperative Barrow Neurological Institute Pain Intensity Score (BNI). Discussion: Endoscopic microvascular decompression is an attractive option for the resolution of neurovas cular conflict as it provides functional results similar to the microscope technique, without requiring an exten sive craniectomy and associated to shorter in-hospital stay, which is beneficial for both the patient and the institution.

Postoperative Third Nerve Palsy after Endoscopic Endonasal Transsphenoidal Surgery for Pituitary Adenoma: Elucidating its Mechanism.

Third nerve palsy is a rare complication of transsphenoidal surgery and has been merely mentioned in different studies, but there is not any rigorous analysis focusing on this particular complication. The purpose of this study is to analyze this complication after transsphenoidal surgery for a pituitary adenoma to better understand its pathophysiology and outcome. The authors retrospectively analyzed 3 cases of third nerve palsy selected from the 377 patients operated via a transsphenoidal route between 2012 and 2021 at FLENI, a private tertiary neurology and neurosurgical medical center located in Buenos Aires, Argentina. The three patients who presented this complication were operated on via an endoscopic approach. It was observed that an extension into the cavernous sinus (Knosp grade 4) and to the oculomotor cistern was present in the three patients. The deficit was apparent immediately after surgery in two patients. For these two patients, the supposed mechanism of ophthalmoplegia was an intraoperative nerve lesion. The other patient became symptomatic in the 48 h following the surgery. The mechanism implied in this case was intracavernous hemorrhagic suffusion. The latter patient completely recovered the third nerve deficit in the 3 months that followed, while the other two recovered after 6 months postoperative. Oculomotor nerve palsy after transsphenoidal surgery is a very rare complication and appears to be transient in most cases. The invasion of both the cavernous sinus and the oculomotor cistern seems to be a major factor in its physiopathology and should be preoperatively analyzed on magnetic resonance imaging (MRI); recognizing such extension should play an important role in the surgeon's operative considerations.

Resultados a largo plazo del tratamiento quirúrgico de las fístulas arteriovenosas durales espinales en un centro Argentino / Surgical treatment of spinal dural arteriovenous fistulas: Management and long-term results in a series of patients operated in an Argentinian center

Resumen Introducción: La fístula dural arteriovenosa espinal (FDAVE) es una enfermedad vascular frecuentemente subdiagnosticada. El tratamiento puede ser microqui rúrgico o endovascular. Métodos: Estudio retrospectivo de una serie de pa cientes con FDAVE tratados por microcirugía entre los años 2010 y 2021. Fueron evaluados parámetros como edad, sexo, cuadro clínico pre y postoperatorio medido con las escalas de Aminoff-Logue y Rankin modificada (mRs). Los estudios diagnósticos se utilizaron para de terminar nivel lesional y resultados quirúrgicos. Resultados: Se incluyeron doce pacientes (10 hombres y 2 mujeres) con un promedio de edad de 60 años. El tiempo de evolución del cuadro clínico al diagnóstico fue menor a 12 meses salvo un caso de 32 meses. Las FDAVE fueron localizadas, 8 a nivel dorsal, 3 a nivel lumbar y una a nivel sacro. La arteria de Adamkiewicz se identificó en 5 casos en L1, 2 en D12, 2 en D10, 2 en D9 y un caso en D7. De los 12 pacientes operados, 3 fueron embolizados previamente; dos permanecieron estables en su evolución y 10 mejoraron uno o más puntos del mRs. No hubo complicaciones en el postoperatorio. Todos mostraron mejoría del edema medular en reso nancia magnética y la angiografía digital, luego de los 6 meses, fue negativa. El seguimiento promedio fue de 40 meses con un rango de 6 a 122 meses y ningún paciente presentó recidiva de la FDAVE. Conclusión: El tratamiento quirúrgico de las FDAVE es un método muy eficaz, de baja morbilidad y menor tasa de recurrencia comparado con el tratamiento en dovascular.

Abstract Introduction: Spinal dural arteriovenous fistula (SDA VF) is a rare vascular disease, of unknown etiology, fre quently underdiagnosed. Treatment can be microsurgical or endovascular. Methods: Retrospective and monocentric analysis of 12 SDAVF patients treated by microsurgery between 2010 and 2021. Parameters including age, sex, pre and postoperative clinical condition were analyzed according to modified Aminoff-Logue and Rankin scales. Diagnos tic studies such as magnetic resonance imaging (MRI), magnetic resonance angiogram (MRA) and spinal digital subtraction angiography (DSA), were evaluated for lesion level, as were surgical results. Results: Twelve patients (10 men and 2 women), average age: 60 years, were operated. The interval from symptom onset to diagnosis was <12 months in all cases except one (32 months). SDAVF locations were thoracic in 8 cases, between T6 and T12, 3 at lumbar spine (L1- L2) and at S1 in one case, with no difference regarding side. The Adamkiewicz artery was identified in 5 cases at L1, 2 at D12, 2 at D10, 2 at D9 and 1 at D7 (7 left-sided and 5 right-sided). Three of the 12 patients operated had undergone prior embolization. Postoperative neu rological outcomes showed: 2 patients remained stable and 10 improved one or more points on the mRs; no postoperative complications were observed. Follow-up MRI images improved in all cases and spinal DSA was negative at 6 months. Average follow-up was 40 months (range 6 to 122) and no patient presented recurrence. Conclusion: Microsurgical treatment of SDAVF proved to be efficient, with low morbidity and lower recurrence rates compared to endovascular results.

Risk Factors Related to Transient Diabetes Insipidus Development Following Transsphenoidal Pituitary Adenoma Resection: A Multicentric Study.

OBJECTIVE: To analyze and find risk factors associated with developing transient diabetes insipidus (DI) using a multicenter case series after trans-sphenoidal surgery. METHODS: Medical records of patients who underwent trans-sphenoidal surgery for pituitary adenoma resection between 2010 and 2021 at 3 different neurosurgical centers by 4 experienced neurosurgeons were retrospectively analyzed. The patients were divided into 2 groups (DI group or control group). Logistic regression analysis was conducted to identify risk factors associated with postoperative DI. Univariate logistic regression was performed to identify variables of interest. Covariates with a P value <0.05 were incorporated into multivariate logistic regression models to identify independently associated risk factors for DI. All statistical tests were conducted using RStudio. RESULTS: A total of 344 patients were included; 68% were women, the mean age was 46.5 years, and nonfunctioning adenomas were the most frequent (171, 49.7%). The mean tumor size was 20.3 mm. Covariates associated with postoperative DI were age, female gender, and gross total resection. The multivariable model showed that age (odds ratio [OR] 0.97, CI 0.95-0.99, P = 0.017) and female gender (OR 2.92, CI 1.50-6.03, P = 0.002) remained significant predictors of DI development. Gross total resection was no longer a significant predictor of DI in the multivariable model (OR 1.86, CI 0.99-3.71, P = 0.063), suggesting that this variable may be confounded by other factors. CONCLUSIONS: The independent risk factors for the development of transient DI were female and young patients.

[Surgical treatment of spinal dural arteriovenous fistulas: Management and long-term results in a series of patients operated in an Argentinian Center]. / Resultados a largo plazo del tratamiento quirúrgico de las fístulas arteriovenosas durales espinales en un Centro argentino.

INTRODUCTION: Spinal dural arteriovenous fistula (SDAVF) is a rare vascular disease, of unknown etiology, frequently underdiagnosed. Treatment can be microsurgical or endovascular. METHODS: Retrospective and monocentric analysis of 12 SDAVF patients treated by microsurgery between 2010 and 2021. Parameters including age, sex, pre and postoperative clinical condition were analyzed according to modified Aminoff-Logue and Rankin scales. Diagnostic studies such as magnetic resonance imaging (MRI), magnetic resonance angiogram (MRA) and spinal digital subtraction angiography (DSA), were evaluated for lesion level, as were surgical results. RESULTS: Twelve patients (10 men and 2 women), average age: 60 years, were operated. The interval from symptom onset to diagnosis was < 12 months in all cases except one (32 months). SDAVF locations were thoracic in 8 cases, between T6 and T12, 3 at lumbar spine (L1-L2) and at S1 in one case, with no difference regarding side. The Adamkiewicz artery was identified in 5 cases at L1, 2 at D12, 2 at D10, 2 at D9 and 1 at D7 (7 left-sided and 5 right-sided). Three of the 12 patients operated had undergone prior embolization. Postoperative neurological outcomes showed: 2 patients remained stable and 10 improved one or more points on the mRs; no postoperative complications were observed. Follow-up MRI images improved in all cases and spinal DSA was negative at 6 months. Average follow-up was 40 months (range 6 to 122) and no patient presented recurrence. CONCLUSION: Microsurgical treatment of SDAVF proved to be efficient, with low morbidity and lower recurrence rates compared to endovascular results.

Introducción: La fístula dural arteriovenosa espinal (FDAVE) es una enfermedad vascular frecuentemente subdiagnosticada. El tratamiento puede ser microquirúrgico o endovascular. Métodos: Estudio retrospectivo de una serie de pacientes con FDAVE tratados por microcirugía entre los años 2010 y 2021. Fueron evaluados parámetros como edad, sexo, cuadro clínico pre y postoperatorio medido con las escalas de Aminoff-Logue y Rankin modificada (mRs). Los estudios diagnósticos se utilizaron para determinar nivel lesional y resultados quirúrgicos. Resultados: Se incluyeron doce pacientes (10 hombres y 2 mujeres) con un promedio de edad de 60 años. El tiempo de evolución del cuadro clínico al diagnóstico fue menor a 12 meses salvo un caso de 32 meses. Las FDAVE fueron localizadas, 8 a nivel dorsal, 3 a nivel lumbar y una a nivel sacro. La arteria de Adamkiewicz se identificó en 5 casos en L1, 2 en D12, 2 en D10, 2 en D9 y un caso en D7. De los 12 pacientes operados, 3 fueron embolizados previamente; dos permanecieron estables en su evolución y 10 mejoraron uno o más puntos del mRs. No hubo complicaciones en el postoperatorio. Todos mostraron mejoría del edema medular en resonancia magnética y la angiografía digital, luego de los 6 meses, fue negativa. El seguimiento promedio fue de 40 meses con un rango de 6 a 122 meses y ningún paciente presentó recidiva de la FDAVE. Conclusión: El tratamiento quirúrgico de las FDAVE es un método muy eficaz, de baja morbilidad y menor tasa de recurrencia comparado con el tratamiento endovascular.

Apoplejía pituitaria e infección por SARS-COV-2 (COVID-19) / Pituitary apoplexy and SARS-CoV-2 (COVID-19) infection

Resumen La infección por coronavirus (SARS-CoV-2/COVID-19) es responsable de un diverso rango de manifestaciones extrapulmonares entre las cuales se destaca el compromiso neurológico directo o indirecto. La apoplejía hipofisaria es una entidad médica y neuroquirúrgica de gravedad variable que suele asociarse a la presencia de un adenoma subyacente. Un escaso número de reportes han vinculado estas dos enfermedades entre sí. Este trabajo describe un caso de apoplejía hipofisaria manifestada clínicamente en for ma concomitante al diagnóstico de COVID 19, en un paciente con macroadenoma hipofisario desconocido y su manejo terapéutico, revisando los mecanismos potencialmente subyacentes al nexo entre ambas entidades.

Abstract Coronavirus disease (SARS-CoV-2/COVID-19) is responsible for a wide variety of extrapulmonary manifestations, among which direct or indirect neurological compromise stands out. Pituitary apoplexy is a clinical and neurosurgical entity of variable severity, usually associated with a pituitary adenoma. Literature is scarce regarding the association between these diseases. This paper reports a case of pituitary apoplexy, manifested concomitantly to the diagnosis of COVID 19 in a patient with unknown pituitary macroadenoma, and its therapeutic management, reviewing the mechanisms potentially underlying the link between both entities.

Frontal Aslant Tract and Its Role in Language: A Journey Through Tractographies and Dissections.

BACKGROUND: The frontal aslant tract (FAT) is a bilateral tract located within each frontal lobe. It connects the supplementary motor area in the superior frontal gyrus with the pars opercularis in the inferior frontal gyrus. There is a new and broader conceptualization of this tract called the extended FAT (eFAT). The eFAT tract role is believed to be related to several brain functions, including verbal fluency as one of its main domains. METHODS: Tractographies were performed by using DSI Studio software on a template of 1065 healthy human brains. The tract was observed in a three-dimensional plane. The Laterality Index was calculated based on the length, volume, and diameter of fibers. A t test was performed to verify the statistical significance of global asymmetry. The results were compared with cadaveric dissections performed according to the Klingler technique. An illustrative case enlightens the neurosurgical application of this anatomic knowledge. RESULTS: The eFAT communicates the superior frontal gyrus with the Broca area (within the left hemisphere) or its contralateral homotopic area within the nondominant hemisphere. We measured the commisural fibers, traced cingulate, striatal, and insular connections and showed the existence of new frontal projections as part of the main structure. The tract did not show a significant asymmetry between the hemispheres. CONCLUSIONS: The tract was successfully reconstructed, focusing on its morphology and anatomic characteristics.

[Pituitary apoplexy and SARS-CoV-2 (COVID-19) infection]. / Apoplejía pituitaria e infección por SARS-CoV-2 (COVID-19).

Coronavirus disease (SARS-CoV-2/COVID-19) is responsible for a wide variety of extrapulmonary manifestations, among which direct or indirect neurological compromise stands out. Pituitary apoplexy is a clinical and neurosurgical entity of variable severity, usually associated with a pituitary adenoma. Literature is scarce regarding the association between these diseases. This paper reports a case of pituitary apoplexy, manifested concomitantly to the diagnosis of COVID 19 in a patient with unknown pituitary macroadenoma, and its therapeutic management, reviewing the mechanisms potentially underlying the link between both entities.

La infección por coronavirus (SARS-CoV-2/COVID-19) es responsable de un diverso rango de manifestaciones extrapulmonares entre las cuales se destaca el compromiso neurológico directo o indirecto. La apoplejía hipofisaria es una entidad médica y neuroquirúrgica de gravedad variable que suele asociarse a la presencia de un adenoma subyacente. Un escaso número de reportes han vinculado estas dos enfermedades entre sí. Este trabajo describe un caso de apoplejía hipofisaria manifestada clínicamente en forma concomitante al diagnóstico de COVID 19, en un paciente con macroadenoma hipofisario desconocido y su manejo terapéutico, revisando los mecanismos potencialmente subyacentes al nexo entre ambas entidades.

Clinical Applicability of the Sellar Barrier Concept in Patients with Pituitary Apoplexy: Is It Possible?

There is evidence of association between sellar barrier thickness and intraoperative cerebrospinal fluid (CSF) leakage, impacting the postoperative prognosis of the patients. The aim of this study is to analyze the clinical applicability of the sellar barrier concept in a series of operated patients with pituitary apoplexy (PA). A retrospective study was conducted including 47 patients diagnosed with PA who underwent surgical treatment through a transsphenoidal approach. Brain magnetic resonance imaging (MRI) of the patients were evaluated and classified utilizing the following criteria: strong barrier (greater than 1 mm), weak barrier (less than 1 mm), and mixed barrier (less than 1 mm in one area and greater than 1 mm in another). The association between sellar barrier types and CSF leakage was analyzed, both pre- and intraoperatively. The preoperative MRI classification identified 10 (21.28%) patients presenting a weak sellar barrier, 20 patients (42.55%) with a mixed sellar barrier, and 17 patients (36.17%) exhibiting a strong sellar barrier. Preoperative weak and strong sellar barrier subtypes were associated with weak (p ≤ 0.001) and strong (p = 0.009) intraoperative sellar barriers, respectively. Strong intraoperative sellar barrier subtypes reduced the odds of CSF leakage by 86% (p = 0.01). A correlation between preoperative imaging and intraoperative findings in the setting of pituitary apoplexy has been observed.

Posterior Fossa Calcifying Pseudoneoplasm of the Neuraxis (CAPNON): Presentation of Three Surgical Cases.

BACKGROUND: Calcifying pseudoneoplasm of the neuraxis (CAPNON) is an extremely rare entity with fewer than 150 cases reported in the literature and mostly with a supratentorial or spinal location. Posterior fossa CAPNON has been reported scarcely, and association with perilesional edema is a topic not yet approached which might play a significant role in treatment decision and clinical progression. Our objective is to report, to our knowledge, the first series of 3 posterior fossa CAPNON surgically treated in a single institution and assess features that help provide a systematic approach to diagnosis and timely treatment. METHODS: This was a monocentric, retrospective study of surgical patients diagnosed with a posterior fossa CAPNON in the last 5 years. A thorough bibliographic research was conducted. RESULTS: Three patients were included. Locations involved IV ventricle, right cerebellopontine angle with extension to foramen magnum, and cerebellar vermis. Two of them presented with symptoms linked to acute hydrocephalus, and the other one presented with progressive cranial nerve palsy and brainstem compression signs. The 3 of them showed radiological signs of perilesional edema on their preoperative magnetic resonance imaging. Gross total resection was accomplished in one case, with near and subtotal resections in the others. There were no complications. The outcome was favorable in all cases. CONCLUSIONS: It is essential to contemplate this infrequent diagnosis in cases of calcified lesions involving the posterior fossa. When symptoms manifest, surgery should be considered. Perilesional edema could be associated with symptomatic progression and hence a sign suggesting the need for surgical treatment.

Surgical Treatment of IV Ventricle Calcifying Pseudoneoplasm of the Neuraxis (CAPNON) Operative Nuances.

Calcifying pseudoneoplasm of the neuroaxis (CAPNON) is a rare, slow growing, and generally benign fibro osseous mass that can emerge throughout the entire central nervous system (CNS). When diagnosed, prompt surgical treatment can determine a good neurological outcome and possibly curative resolution. The objective of the present work is to present a step by step technical report with its video. We present a 37 year old female presented with occipital headache and cervical pain associated with dysphagia, nausea, and gait disturbances. Computed tomography (CT) scan showed a focal calcified lesion on the floor of the IV ventricle projecting toward the vermis with associated supratentorial hydrocephalus and transependymal edema. The telovelar approach was chosen for the procedure. The outcome was favorable, with no complications. Postoperative CT was performed, which revealed no residual lesion. A step by step report of a IV ventricle CAPNON that manifested with hydrocephalus is described.

ß-Catenin is reduced in membranes of human prolactinoma cells and it is inhibited by temozolomide in prolactin secreting tumor models.

INTRODUCTION: Prolactinomas are the most frequent pituitary tumor subtype. Despite most of them respond to medical treatment, a proportion are resistant and become a challenge in clinical management. Wnt/ß-Catenin pathway has been implicated in several cancers including pituitary tumors and other sellar region malignancies. Interestingly, Wnt/ß-Catenin inhibition augments the cytotoxicity of the chemotherapeutic agent Temozolomide (TMZ) in different cancers. TMZ is now being implemented as rescue therapy for aggressive pituitary adenoma treatment. However, the molecular mechanisms associated with TMZ action in pituitary tumors remain unclear. OBJECTIVES: Our aims in the present study were to evaluate differential ß-Catenin expression in human resistant prolactinomas and Wnt/ß-Catenin signaling activation and involvement in Prolactin (PRL) secreting experimental models treated with TMZ. RESULTS: We first evaluated by immunohistochemistry ß-Catenin localization in human resistant prolactinomas in which we demonstrated reduced membrane ß-Catenin in prolactinoma cells compared to normal pituitaries, independently of the Ki-67 proliferation indexes. In turn, in vivo 15 mg/kg of orally administered TMZ markedly reduced PRL production and increased prolactinoma cell apoptosis in mice bearing xenografted prolactinomas. Intratumoral ß-Catenin strongly correlated with Prl and Cyclin D1, and importantly, TMZ downregulated both ß-Catenin and Cyclin D1, supporting their significance in prolactinoma growth and as candidates of therapeutic targets. When tested in vitro, TMZ directly reduced MMQ cell viability, increased apoptosis and produced G2/M cell cycle arrest. Remarkably, ß-Catenin activation and VEGF secretion were inhibited by TMZ in vitro. CONCLUSIONS: We concluded that dopamine resistant prolactinomas undergo a ß-Catenin relocalization in relation to normal pituitaries and that TMZ restrains experimental prolactinoma tumorigenicity by reducing PRL production and ß-Catenin activation. Together, our findings contribute to the understanding of Wnt/ß-Catenin implication in prolactinoma maintenance and TMZ therapy, opening the opportunity of new treatment strategies for aggressive and resistant pituitary tumors.

Subarachnoid Hemorrhage From Rupture of an Undiagnosed Posterior Circulation Aneurysm During Sellar Tumor Surgery.

Association between cerebral aneurysms and sellar tumors has been previously reported. Rupture of anterior circulation aneurysms during a transsphenoidal surgery causing massive subarachnoid hemorrhage (SAH) is uncommon, but rupture of a posterior circulation aneurysm is an infrequent event. We present three cases of SAH secondary to rupture of an undetected posterior circulation aneurysm during transsphenoidal surgery to treat a sellar tumor. The common factor in these cases was the adverse outcome despite treatment.  The fatal outcome seen in all these cases questions whether to include a (magnetic resonance) MR angiography or (computed tomography) CT angiography during preoperative evaluation for sellar tumors in order to identify inadvertently associated aneurysms.