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.

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.

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.

Revascularizacion cerebral en el moyamoya del adulto / Cerebral revascularization in adult moyamoya

Introducción: el Moyamoya (MM) es una enfermedad crónica esteno-oclusiva de los vasos arteriales intracraneanos asociado al desarrollo secundario de arteriolas dilatadas en la base del cerebro. La historia natural de la enfermedad predispone a infartos y/o hemorragias cerebrales. El objetivo del presente trabajo es mostrar nuestra experiencia en el manejo quirúrgico del MM del adulto. Material y método: se realizó una revisión retrospectiva de 11 pacientes adultos con diagnóstico de MM tratados entre mayo 2014 y mayo 2020. Se analizaron las historias clínicas, estudios diagnósticos, protocolos y videos operatorios. En el preoperatorio se utilizó la escala angiográfica de Suzuki y para la valoración clínica pre y postoperatoria la escala de Rankin modificada. Resultados: se operaron 11 pacientes (8 femeninos), 9 son portadores de EMM y 2 con SMM secundario a NF1 y enfermedad de Hashimoto. Se realizaron 16 procedimientos de revascularización en 11 pacientes (en 5 pacientes la revascularización cerebral fue bilateral), 12 fueron combinados (bpTS más EDMS) y en 4 sólo sinangiosis tipo EDAMS.El aumento del flujo sanguíneo cerebral se constató en todos los casos mediante ADC luego de los 6 meses de la cirugía. La permeabilidad del bpTS se comprobó en 10 de 12 bpTS (83.3 %) y la revascularización de la sinangiosis fue muy buena en todos los pacientes. El 82 % de los pacientes mejoraron un punto o más en la escala de Rankin y un paciente presentó un infarto frontal en TAC postoperatoria sin repercusión clínica. Conclusiones: la evolución natural de la enfermedad conduce al deterioro neurológico por ACV isquémico y/o hemorrágico. En nuestra experiencia, la mejor opción terapéutica en el adulto es la revascularización cerebral combinada porque disminuye la incidencia de ACV con resultados favorables y escasa morbilidad

Introduction: Moyamoya is a chronic steno-occlusive disease of the intracranial vessels associated to the secondary development of dilated arterioles at the base of the brain. The natural history of the disease predisposes to cerebral infarcts and/or hemorrhages. The objective of this paper is to show our experience and surgical management of adult moyamoya. Materials and Methods: retrospective review of 11 adult patients with moyamoya treated from May 2014 to May 2020 was performed. Clinical charts, neuroimaging studies, operative records and surgical videos were analyzed. The Suzuki scale was used as a preoperative score, and the modified Rankin scale was used for pre and postoperative clinical assessment. Results: Eleven patients (8 females) were operated at our Institution: 9 are MMD and 2 MMS secondary to NF1 and Hashimoto disease. We performed 16 cerebral revascularizations in 11 patients (in 5 patients thecerebral revascularization was bilateral), 12 were combined (STA-MCA bypass plus EDMS) and in only 4 EDAMS synangiosis was done.The increase in cerebral blood flow was verified in all cases by follow-up DSA at 6 months. The STA-MCA bypass permeability was verified in 10 of 12 cases (83.3%) and the revascularization by synangiosis was demonstrated in all patients. Clinical follow-up showed that 82 % of the patients improved one point or more on the modified Rankin scale and one patient presented a frontal infarction on postoperative CT without clinical worsening. Conclusions: The natural course of the disease leads to neurological deterioration due to ischemic and hemorrhagic stroke. According to our experience, the best therapeutic option in adults is combined cerebral revascularization because it decreases the incidence of stroke with good results and low morbidity

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.

Asistencia Endoscópica en la Descompresión Microquirúrgica del Hemiespasmo Facial / Endoscopic Assistance in Microsurgical Decompression of Facial Hemiespasm

Introducción: El hemiespasmo facial primario (HFP) se produce por la hiperexcitabilidad del nervio facial y sus núcleos de origen como consecuencia de la compresión vascular. La cirugía de descompresión neurovascular se plantea como alternativa al tratamiento médico refractario. Objetivos: Presentar nuestra experiencia respecto a esta patología. Material y métodos: Se realizó una revisión retrospectiva de pacientes operados por HPF refractarios a tratamiento médico en nuestra institución en los últimos 5 años (periodo 2014-2019). Todos fueron intervenidos vía retrosigmoidea. Se evaluaron datos demográficos, evaluación prequirúrgica y evolución postoperatoria. Resultados: Se operaron 4 pacientes bajo técnica microquirúrgica asistido por endoscopía. Edad promedio 52 años (rango 41-61) con una relación femenino masculino 3:1. El 25% (n=1) presentaba paresia facial grado 2 (HB) en el prequirúrgico. No hubo cambios en cuanto al grado de paresia facial en el postoperatorio en ningún caso. Sólo un paciente registró caída leve en la audiometría postquirúrgica. El 75% (n=3) resolvieron el HFP. Conclusión: Si bien nuestra serie es acotada a un número reducido de pacientes, la cirugía descompresiva microvascular es efectiva como alternativa al tratamiento médico refractario del HFP.

Introduction: Primary hemifacial spasm (PHS) is defined as the hyper excitability of the nerve due to the compression of the facial nerve or its nuclei, most commonly by a vascular structure. The surgical indication for microvascular decompression is resistance to pharmacological treatment or severe adverse effects. Objectives: To present our experience in the surgical treatment of this pathology with this novel technique. Materials and methods: We retrospectively reviewed all patients (n=4) with a diagnosis of PHS, who underwent endoscope-assisted microvascular decompression surgery in our institution during the last 5 years. In all the cases, we choose the retrosigmoid approach. We evaluated demographic data, preoperative evaluation, and post-operative evolution. Results: Endoscope-assisted microvascular decompression was the surgical technique in all the patients. The median age was 52 years, the female-male ratio of 3:1. Only one patient presented a grade 2 facial palsy (House-Brackmann scale) in the preoperative evaluation; there were no significant changes in the post-operative evaluation in any patient. Only one patient experienced worsening in the post-operative audiometric follow-up. The 75% (n=3) of the patients solved the HFP after the surgical treatment. Conclusion: By taking into account our experience in this small case series, we can support the concept that endoscope-assisted microvascular decompression is as effective as the open surgical treatment of the PHS.

The role of surgery in primary central nervous system lymphomas / El rol de la cirugía en los linfomas primarios del sistema nervioso central

ABSTRACT Background Primary central nervous system lymphomas (PCNSL) are infrequent. The traditional treatment of choice is chemotherapy. Complete resections have generally not been recommended, because of the risk of permanent central nervous system deficits with no proven improvement in survival. The aim of the current study was to compare survival among patients with PCNSL who underwent biopsy versus surgical resection. Methods A retrospective study was conducted on 50 patients with a confirmed diagnosis of PCNSL treated at our center from January 1994 to July 2015. Results Patients in the resection group exhibited significantly longer median survival time, relative to the biopsy group, surviving a median 31 months versus 14.5 months; p = 0.016. Conclusions In our series, patients who had surgical resection of their tumor survived a median 16.5 months longer than patients who underwent biopsy alone.

RESUMO Introducción Los linfomas primarios del sistema nervioso central (LPSNC) son infrecuentes. Tradicionalmente el tratamiento de elección es la quimioterapia. Existe un paradigma de no indicar resección, por el riesgo de déficit neurológico sin aumento de la sobrevida. El objetivo del presente estudio es comparar la sobrevida de pacientes con LPSNC sometidos a biopsia versus resección. Métodos Estudio retrospectivo que incluye 50 pacientes con diagnóstico confirmado de LPSNC tratados en nuestra Institución desde enero de 1994 hasta julio de 2015. Resultados Los pacientes del "grupo resección" mostraron una sobrevida media significativamente mayor respecto a los del "grupo biopsia"; 31 meses versus 14,5 meses respectivamente, p = 0,016. Conclusiones En nuestra serie, los pacientes que con resección quirúrgica de su tumor tuvieron una sobrevida media de 16,5 meses superior que los pacientes biopsiados.

Meningiomas intraventriculares: reporte de 7 casos y revisión bibliográfica / Intraventricular meningiomas: report of 7 cases and bibliographic review

Introducción: Los meningiomas intraventriculares tienen una baja prevalencia. Dado su origen en plexos coroideos o tela coroidea presentan predilección por los ventrículos laterales. Suelen ser de gran tamaño al momento diagnóstico y de histología preponderantemente benigna. Materiales y Métodos: Realizamos revisión retrospectiva de historias clínicas de pacientes operados de estos tumores durante el período 1999-2014, en nuestra institución junto a una revisión bibliográfica. Resultados: Se operaron siete pacientes con meningiomas intraventriculares de los cuales seis tuvieron localización atrial, cinco fueron derechos y uno izquierdo; el caso restante corresponde a una lesión del IV ventrículo. Todos fueron de sexo femenino con edad promedio de 49 años. La presentación clínica prevalente fue cefalea, trastorno cognitivo leve y hemianopsia homónima en los tumores supratentoriales. Disfunción trigeminal y facial periférica izquierda, disfagia y ataxia troncal se observaron en la lesión del IV ventrículo. Se realizaron dos abordajes parietales, uno precuneal, tres temporales y un abordaje telovelar. En el postoperatorio, 2 pacientes presentaron hemianopsia homónima secuelar. Dos pacientes presentaron signos de atipia por lo cual recibieron radioterapia postoperatoria. Conclusión: Dada su escasa prevalencia el objetivo quirúrgico en meningiomas intraventriculares es la remoción completa con la menor morbilidad postoperatoria posible. En los casos atípicos sugerimos realizar radioterapia postoperatoria para reducir el riesgo de recidivas.

Introduction: Intraventricular meningioma’s have a low prevalence. Given its origin in choroid plexus or tela choroidea presents predilection by the lateral ventricles. They tend to be large at the time of diagnosis and predominantly benign histology. Methods: We performed retrospective review records of patients operated of intraventricular meningioma’s during the period 1999-2014 in our institution with a review of the literature. Development: We operated seven patients with these tumors, six with atrial location, five were right and one left; the remaining case corresponds to a lesion in the fourth ventricle. All were female with an average age of 49 years. The prevalent clinical presentation was headache, mild cognitive disorder and homonymous hemianopsia in supratentorial tumors. Trigeminal and peripheral left facial dysfunction, dysphagia and central ataxia were observed in the lesion of the fourth ventricle. Parieto-occipital two approaches, one interhemispheric precuneal approach, three temporal and a telovelar approach were carried out. Postoperatively, two patients had homonymous hemianopsia. Two patients presented signs of atypia which received postoperative radiation therapy.Conclusion: Given its low prevalence the surgical goal in intraventricular meningiomas is complete removal with less possible postoperative morbidity. In atypical cases we suggest to perform postoperative radiotherapy to reduce risk of recurrence.

Aspergilosis cervical con diseminación al sistema nervioso central. Presentación de caso y revisión de bibliografía / Cervical aspergillosis with dissemination to the central nervous system. Case presentation and bibliography review

INTRODUCCIÓN: la Aspergilosis Invasiva (AI) del Sistema Nervioso Central (SNC) es infrecuente y ocurre generalmente en pacientes inmunocomprometidos. Puede presentarse con cuadros de meningitis, aneurismas micóticos, infartos o abscesos. Es una infección con pronóstico reservado y puede afectar el SNC de forma primaria o secundaria a partir de un foco que se disemina por vía hematógena. Presentamos el caso de un paciente con AI con invasión primaria a nivel óseo y diseminación posterior al cerebro. CASO CLÍNICO: paciente masculino de 25 años con diagnóstico de leucemia linfática aguda en tratamiento quimioterápico que presentó neumonitis por metotrexate por lo que inicia tratamiento con corticoides. Posteriormente agregó cervicalgia y con el diagnóstico de osteomielitis cervical se realiza punción bajo tomografía computada (TC) sin aislarse gérmenes. Se colocó Halo Vest e inició tratamiento antibiótico empírico. Posteriormente presentó afasia de expresión secundaria a lesión frontal izquierda. Se realizó evacuación de absceso cerebral aislando A. fumigatus. El tratamiento antibiótico específico posterior permitió una buena respuesta clínica y radiológica. CONCLUSIÓN: la presencia de lesiones en el SNC de pacientes inmunocomprometidos debe incluir a las micosis como diagnóstico diferencial. La evacuación quirúrgica permite llegar rápidamente al diagnóstico mejorando la respuesta posterior al tratamiento antibiótico. Para evaluar la respuesta terapéutica y posibles recaídas se debe realizar un seguimiento periódico clínico radiológico

INTRODUCTION: invasive aspergillosis (IA) of the central nervous system (CNS) is an uncommon condition that usually occurs in immunocompromised patients. This illness can manifest as meningitis, or as a micotic aneurism, stroke or abscess. The infection affects the CNS either primarily or, more often, secondarily via blood dissemination from a distant focus, and has a poor prognosis. We present a patient with IA primarily affecting the cervical bones, with later spread into the brain. CASE REPORT: a 25-year old male was receiving chemotherapy for acute lymphocytic leukemia when he developed pneumonitis secondary to methotrexate and was started on corticosteroids. He subsequently developed cervicalgia, prompting a needle biopsy of the fourth vertebrae, after which a diagnosis of osteomyelitis was made. Even though the biopsy culture was negative, empirical antibiotics were initiated. A parietal lobe lesion was treated surgically months later after the patient presented with three episodes of transient aphasia. After A. fumigatus grew in culture, the patient's antibiotic regimen was changed to treat the specific agent with a good response. CONCLUSION: IA must be considered a possibility whenever an immunocompromised patient presents with a new brain lesion. These lesions require surgical evacuation, a procedure that allows for diagnostic confirmation and enhances prognosis. Appropriate anti-fungal therapy must be started as soon as the diagnosis is confirmed. In addition, the patient's neurological exam must be repeated and images obtained periodically to monitor treatment and detect possible recurrences

Evaluación de los plexos y nervios periféricos con neurografía por RM de alta resolución en 3T / Evaluation of peripheral plexuses and nerves with high resolution MRI neurography in 3T

La neurografía por RM, se ha convertido en una modalidad diagnóstica ampliamente utilizada para la evaluación de los nervios periféricos y plexos lumbosacro y braquial.El estudio de las NP tradicionalmente perteneció al campo de la neurofisiología, siendo el electromiograma (EMG) el método más utilizado. La neurografía por RM, permite evaluar la estructura fascicular normal de los nervios y los tejidos perineurales, diferenciándolos entre si y, de esa manera detectar y caracterizar anormalidades. En este trabajo, revisamos la anatomía del nervio periférico y del tejido perineural por RM, descripción de las secuencias neurográficas en RM 3T, mención de las patologías que afectan a los nervios periféricos y los plexos braquial y lumbosacro, así como una descripción de las anormalidades musculares que derivan de las lesiones de los nervios periféricos.

Magnetic Resonance Neurography has become a diagnostic tool extensively used for the evaluation of peripheral nerves, lumbosacral and braquial plexus.Traditionally, neuropathies have been assessed by electrophysiological means, being EMG the tool most frequently used.MR Neurography makes it possible to distinguish the normal fascicular pattern of nerves and perineural tissues, and to detect and characterize the abnormalities.In this article we describe the anatomy of peripheral nerves and perineural tissues, the neurography sequences in MRI 3T, the most prevalent diseases that affect them, and the muscle abnormalities that originate from the denervation.

Hidrocefalia externa del adulto: manejo terapéutico y diagnóstico diferencial conhematoma subdural crónico e higroma subdural. Presentación de un caso y revisión de la literatura / Adult external hydrocephalus- therapeutical measures & differential diagnosis with chronic subdural hematoma & subdural higroma: case report & literature review

Objetivo: presentar un caso de hidrocefalia externa en un adulto. Presentación: paciente de 73 años con trastornos en la marcha y paresia braquial derecha de tres semanas de evolución secundarios a hematoma subdural (HSD) frontotemporoparietal izquierdo. Intervención: tras doble evacuación y craniectomía descompresiva por resangrado en postoperatorio inmediato, evolucionó con sensorio fluctuante y confuso, evidenciando en tomografías computadas (TAC) controles colecciones líquidas bilaterales extraaxialescon ventrículos, surcos y cisternas conservados, “signo de venas corticales” a través de cada colección con herniación de ésta a través de la craniectomía. Por punción transcutánea a través de ella se mide la presión del espacio subdural de 26 cm de H2O apoyando el diagnóstico de HEA. Se coloca drenaje subduroperitoneal bilateral logrando una evolución favorable. Conclusión: el manejo terapéutico óptimo de las colecciones subdurales aún no ha sido establecido. La conducta conservadora resulta adecuada en casos asintomáticos y sin efecto de masa mientras que en efusiones subdurales bastaría irrigar la cavidad o una derivación subduroperitoneal. Las derivaciones de LCR resultan de impredecible eficacia en HEA y las colecciones asociadas persisten o recidivan tras su evacuación, por lo que una correcta selección de pacientes es clave antes de cualquier decisión terapéutica.

Schwannomas vestibulares quísticos / Cystic vetibular schwannomas

Objetivo. Presentar nuestra experiencia en el tratamiento de los Schwannomas vestibulares quísticos comparándolos con lesiones sólidas. Material y método. Se evaluaron en forma retrospectiva los síntomas de presentación clínica, tasas de preservación facial, grado de resección quirúrgica, complicaciones postoperatorias y hallazgos histológicos de los Schwannomas quísticos pareados en base al tamaño tumoral con un grupo de lesiones sólidas. Resultados. Durante el período junio 1995 julio 2010, 27 pacientes con Schwannomas quísticos se operaron en nuestro Departamento. El diámetro promedio fue de 29,6 mm. Los síntomas de presentación clínica más frecuentes fueron la hipoacusia, inestabilidad en la marcha y parestesias faciales. Al año de cirugía, el 74% de los pacientes tenían función facial HB I-III sin diferencias significativas con el grupo de lesiones sólidas. La remoción completa fue 55,5% y 85% de los pacientes en las lesiones quísticas ysólidas respectivamente. Conclusión. Los Schwannomas quísticos deben ser evaluados en forma separada de las lesiones sólidas debido a que pueden crecer rápidamente, presentar mayor complejidad quirúrgica y desarrollar complicaciones postoperatorias con mayor frecuencia.

Objective. To present our experience treating this rare tumor variant.Material and Method. Retrospective evaluation of an institutional cystic vestibular schwannoma series, based on initial symptoms, rate of facial preservation, extent of surgical resection, postoperative complication rate and cystic lesion quantificationon histology in comparison to solid tumor type. Results. During the period June 1995-July 2010, 27 cysticschwannomas were operated on at the FLENI neurological Institute. Mean tumor diameter was 29,6mm. The most frequent presenting symptoms included hypoacusia, unsteadiness and facial paresthesias. One year after surgery, 74% of patients presented facial function HB I-III, showing no statistical difference in comparison to solid lesions. Complete surgical resectionwas possible in 55, 5% of the cystic and 85% of the solid tumor groups, respectively. Conclusion. Cystic vestibular schwannomas should be identified separately from vestibular schwannomas in general, particularlybecause they often undergo more rapid expansion, and may present greater surgical risk as well as higher rates ofpostoperative complications.

Diseminación meníngea atípica en meningiomas anaplásicos / Atypical meningeal dissemination in anaplastic meningioma

Objective. To present two cases of aplastic meningiomas refractory to surgical and radiotherapeutic tretement, with torpide evolution and clinical deterioration. Descpription. Case 1. 61, female. Left extraaxial temporo-occipital formation enhancing with gadolinium, tentorial implantation. Simpson II resection. PA: atypical metaplasic meningioma, EMA, VIM and PGR positive, Ki-67; 13%. Without parenchimal infiltration. Local 3D radiotherapy. Visual deterioration, walk disturbance. Relapse with compromise of rectus and transverse sinuses. Simpson II resection. In 12 months, progression of the disease along the convexity. Paliative treatement with hidroxiurea. Case 2: 69, female. Rt. Occipito-parietal meningioma 1995 subtotal resection in other center. Radiotherapy of remnant tumor. 2001 reoperated. Simpson II resection. PA: meningtheliomatous meningioma Ki-67: 5%. Dec. 2006 total resection of relapsing anaplastic meningioma. June 2007, extensive FPT dural dissemination. Medical treatement. Discussion. Anaplasic meningiomas present an exponential growing pattern that differenciates them from better grade lesions, possibly mediated by genetic factors (10q, 14q, 9p deletions). However, the only independent predictor seems to be the cellular kinetic index Ki-67. 5yr. 95% and 10yr. 79% survival rates are reported for anaplastic meningiomas with shorter relapse delays. Conclusion. High aggressive recurrent dissemination of anaplastic meningiomas is uncommon. Simpson´s I or II total resection is the initial tratement complemented as second line treatement by radiotherapy. Chemotherapy is of scant utility.

Meningiomas del surco olfatorio: tratamiento quirúrgico / Olfactory groove meningiomas: surgical treatment

Objective. To present our experience in the management of olfactory goove meningiomas analyzing their clinical presentation, radiological features, surgical outcomes and postoperative complications. Methods. A retrospective study was conducted by analyzing the charts of the patients including surgical records, imaging studies and histopatological records. Results. A total of 304 meningiomas were operated on betwiin 1994-2007 in our department. There were 16 patients with olfactory groove meningiomas including 9 women and 7 men. A men age of 52.8 yr (age range 21-72yr). The most frequent symptom was a higher function impairment (5pt). Olfactory simptons were infrequent in our series. The average maximum tumoral diameter was 5.8 cm. The approaches used were the subfrontal, bifrontal craniotomy with orbital osteotomy, pterional and frontolateral. CSF fistula was the most frequent complication. Perioperative mortality was recorded in two cases. No relation with surgery was demonstrated. The mean follow-up period was 78 months. Conclusion. The olfactory groove meningiomas reaches a big size due to delay in diagnosis. The best treatment is the surgical excision with a surgical approach wich provides quick access to the tumor with the lesser morbimortality possible.

Quistes dermoides y epidermoides intracraneales / Dermoid and epidermoid itracranial cysts

Objective. To present the clinical and radiologic features and surgical results in the management of dermal and epidermal cysts treated in our institution between 1997 and 2006. Material a method. Age, sex, way of presentation, location, radiologic features, surgical technique and compications of 15 epidermal and 1 dermal tumors diagnosed between may 1997 and October 2006, were retrospectively assessed. Results. Mean age: 43 yrs. Most frequent clinical manifestation: headache. Most tumors were at CPA. All resections were done with microsurgical technique. There were 3 cases of chemical meningitis that resolve without sequel. Discussion. Dermal and epidermal cysts are originated by inclusion of ectodermic material at the moment of occlusion of the neural tube. They represent the 0.3-1.5 of intracranial tumors beeng dermal 5-9 times less frequent. The most frequent location of epidermal cysts is at the CPA while dermal are more frequent in the midline. Clinical fatures depend on location. MRI is the gold standard for diagnosis, epecially the DWI sequence. CT is important for the detection of bone invasion. Treatement is so extensive as possible surgical resection, difficult, sometimes because of strong adhesions to eloquent structures. Conclusion. Dermal and epidermal cysts are high fat content lesions, that produce edherence to neural structures. Surgical excision is the election tratement.

Síndrome de área motora suplementaria postoperatoria: Reporte de un caso / Postoperative supplementary motor area syndrome: Report of one case

Objective: To analyze the anatomical and semiological features of the syndrome of the SMA through the presentation of a patient. Description: 55 female. Two yrs history of generalized convultions. Left frontomedial lesion biopsied outwards. PA: low grade astrocytoma. Medically trated until feb 2007. Sudden headache and right sided hemiparesis with crural predominance. Hoffmann and slight right hyper reflexia. MRI: expansion of primary lesion with intra lesional hemorrhage. Surgical resection. PA: mixed anaplastic glioma. The inmediate postoperative status was of a right CB plejia with severe apathy and abulia with right spatial hemineglect and hypofluent and anomic language, with preserved repetition and comprehension. Total recovery of paresis and language except when stressed. Discussion: The SMA is limited by cingulated cortex inferiorly, PMC posteriorly, and vertex surperiorly. The anterior border is not well defined. SMA activates before the PMC, during planification and iniciation of movement. Is connected with the PMC, spinal cord neurons, basal ganglia and contralateral SMA. By intraoperative stimulation it could be established the somatotopic organization of SMA, with the hindlimb posterior the forelimb intermediate and face anterior. Before the facial representation is the language area in the dominant hemisphere. Epileptogenic crisis originated in this area produce abduction and supination of the contralateral forelimb with deviation of the head to the same side. The syndrome of lesion of SMA includes: global akinesis, proximal predominance of motor deficit, with secuelar difficulty for the fine movements of hands an a quick recuperation (days to weeks). Conclusion: The syndrome of the supplementary motor area is well recognized after medial frontal lobe surgery. Its features include reduction of spontaneous movements in the contralateral limbs and speech deficit. The impairment of volitional movements is the main finding...

Angiomas cavernosos de tronco cerebral / Brain stem cavernous angiomas

Introduction: The incidence of intracranial aneurysm ranges from 0,5 to 0,6 por ciento and the diagnosis of incidental aneurysms has increased due to the development of non invasive neuroimaging techniques. Minimally invasive treatment modality in incidental cases. Methods: A series of 119 incidental aneurysms in 77 patients were treated by embolization with GDC coils. Results: One hundred and seven aneurysms were succesfully embolized with total or almost total occlusion rate of 86,8 por ciento. Thirteen procedural complications occurred causing definite morbidity in 5 patients and one death. None of the embolized aneurysms bled during the follow up. Conclusion: Embolization of incidental aneurysms is associated to a low morbidity and mortality rates

Neuronavegacion en cirugias intracraneales / Neuronavigation in intracranial surgeries

Objectives: to present our experience with Neuronavigation system in intracranial surgery. Material and Methods: The use of neuronavigation system was evaluated in 104 consecutive patients operated on during the period September 1999 - April 2003 (Range of age: 5 months - 75 years). Surgical procedures included the remotion of brain tumor, arteriovenous malformation, cavernous angiomas and epilepsy surgeries. The neuronavigation system is the Elekta Insight View Scope (Elekta Instrumental). Results: The additional time required for preoperative organization of the Neuronavigation system was 30 minutes. There were no differences during the registration process related to the surgical position (prone, supine and park-bench). The reference system planning of the surgical approach, to guide endoscopical procedures, perform smaller craniotomies, localize deep-seated subcortical lesions, identify the boundaries of low grade tumors and evaluate the extent of resection in epilepsy surgeries. Conclusion: Neuronavigation system improves the surgical approach of intracranial surgeries allowing to short the operating time, define the less invasive trajector, and identify the margins of low grade lesions