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 (tMRI) in glioma surgery in awake patients. 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 and 2022. Only patients with pathology-confirmed gliomas, with 6-month follow-up, who had preoperative and postoperative volumetric magnetic resonance imaging, 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. CONCLUSIONS: 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.

[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.

Microcirugía de las fístulas durales arteriovenosas espinales, más un repaso de la anatomía vascular vertebromedular / Microsurgery of spinal dural arteriovenous fistulas, plus a review of the vertebromedullary vascular anatomy

Introducción: la fístula dural arteriovenosa espinal (FDAVE) es una enfermedad vascular rara, de etiología desconocida y frecuentemente subdiagnosticada. El tratamiento puede ser microquirúrgico o endovascular. Material y Método: Análisis retrospectivo de una serie de 8 pacientes consecutivos con FDAVE tratados por microcirugía entre 2010 y 2020. Fueron evaluados parámetros como edad, sexo, cuadro clínico pre y postoperatorio medido con las escalas de Aminoff-Logue y Rankin modificada. Los estudios diagnósticos con RMN (Resonancia Magnética Nuclear), ARM (Angio Resonancia Magnética) y ADM (Angiografía Digital Medular) se utilizaron para determinar nivel lesional y resultados quirúrgicos. Resultados: Fueron operados 8 pacientes (7 masculinos y 1 femenino) con un promedio de edad de 58 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 en: 6 a nivel dorsal entre D6 y D12, una en L2 y la última en S1 (5 derechas y 3 izquierdas). La arteria de Adamkiewicz se identificó en: 4 casos en L1, 2 en D12, 1 en D10 y un caso en D7 (6 izquierdas y 2 derechas). De los 8 pacientes operados, 3 fueron embolizados previamente. La evolución postoperatoria del cuadro neurológico fue: 2 de 8 permanecieron estables y 6 de 8 mejoraron uno o más puntos en la escala de Rankin modificada; no hubo complicaciones en el postoperatorio. Todos los pacientes mejoraron las imágenes en RMN diferida y la ADM luego de los 6 meses fue negativa. El seguimiento promedio fue de 48 meses con un rango de 11 a 116 meses, ningún paciente presentó recidiva de la FDAVE. Conclusiones: El tratamiento quirúrgico de las FDAVE es un método muy eficaz, de baja morbilidad y menor tasa de recurrencia comparado con el tratamiento endovascular.

Introduction: Spinal dural arteriovenous fistula (SDAVF) is a rare vascular disease, of unknown etiology and frequently underdiagnosed. Treatment can be microsurgical or endovascular. Material and Method: Retrospective analysis of a series of 8 SDAVF patients treated by microsurgery between 2010 and 2020. Parameters including age, sex, pre and postoperative clinical condition were analyzed according to modified Aminoff-Logue and modified Rankin scales. Diagnostic studies such as MRI (Magnetic Resonance Imaging), MRA (Magnetic Resonance Angiogram) and spinal DSA (Digital Subtraction Angiography), were evaluated for lesion level, as were surgical results. Results: Eight patients (7 male and 1 female), average age of 58 years were operated. The interval from symptom onset to diagnosis was less than 12 months in all cases except one (32 months). SDAVF locations were thoracic in 6 cases between T6 and T12, at L2 in one and at S1 in one case (5 on the right and 3 on the left). The Adamkiewicz artery was identified in: 4 cases at L1, 2 at D12, 1 at D10 and in one case at D7 (6 left-sided and 2 right-sided). Three of the 8 patients operated had undergone prior embolization. Postoperative neurological outcomes showed: 2 patients remained stable and 6 had improved one or more points on the modified Rankin scale; no postoperative complications were observed. Follow-up MRI images improved in all cases and spinal DSA was negative at six months. Average follow-up was 48 months (range 11 to 116 months), no patient presented recurrence. Conclusions: Microsurgical treatment of SDAVF proved to be efficient, with low morbidity and lower recurrence rates compared to endovascular results.