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.

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.

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.

Spinal neurenteric cyst is a rare lesion, only anecdotal case reports have been published. The neurenteric cyst accounts for 0.3 to 1.3% of spinal axis tumors. It affects the inferior cervical and superior thoracic spine level. Approximately 90% of neurenteric cysts are located in the intradural/extramedullary compartment while the remaining10% are divided between an intradural/intramedullary or extradural location. Surgical intervention with radical resection is the best treatment. The outcome is favorable and the recurrence rates after partial resection are low.

El quiste neuroentérico espinal es una lesión de rara presentación, sólo existen reportes de casos aislados. Representa del 0,3% al 1,3% de los tumores espinales según las distintas citas bibliográficas. Suele afectar el canal espinal, especialmente a nivel cervical bajo y torácico superior. Aproximadamente el 90% de estos quistes se localiza en el espacio intradural/ extramedular, mientras que el 10% restante se divide entre la localización intradural/intramedular o extradural. El tratamiento de los quistes neuroentéricos intraespinales es quirúrgico, mediante la resección lo más radical posible. Los resultados son favorables y las tasas de recurrencia después de la resección parcial son bajas.

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 quantification on histology in comparison to solid tumor type. Results. During the period June 1995-July 2010, 27 cystic schwannomas 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 diffe-rence in comparison to solid lesions. Complete surgical resection was 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, particularly because they often undergo more rapid expansion, and may present greater surgical risk as well as higher rates of postoperative complications.

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 y sólidas 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 describe two cases of cerebellar hematomas after supratentorial surgeries: a subdural hematoma (case 1) and subdural hygroma (case 2). Materia and Method. An analysis of the clinical records and images of two patients evaluated during 2009 at the Clinicas Hospital and at the Spanish Hospital. Results. Case 1, 70 years old male, with a left hemiparesis and a lucid status after evacuation of subdural hematoma suffered a 2.5 cm bleeding in the cerebellar folias and in the vermis after 72 hs of the surgery. The evolution was unfavorable with a sudden neurological deficit and cardiorespiratory failure. Case 2, 40 years old female, with asymptomatic 1 cm vermian hematoma found in the CT scan control after 72 hs of the surgery. Evolution was without neurological deficit. Conlusion. Supratentorial surgery with considerable outflow of cerebrospinal fluid would be the one most important factor in this complication. The cerebrospinal overdrainage produces cerebellar relaxation with the consequent traction and rupture of the brinding veins toward the tentorium, generating subdural haematomas and cerebellar hemorragic venous infarction. These two cases reported were operated with non aspirative subdural drainages with considerable cerebrospinal outflow for 72 and 48 hs respectively, that is the common etiologic pattern according to most of the authors.

Objetivo. Describir dos casos de hematoma cerebeloso después de cirugía supratentorial: un hematoma subdural (caso 1) y un higroma subdural (caso 2). Material y método. Análisis de las historias clínicas e imágenes de dos pacientes evaluadas en el Hospital de Clínicas y en el Hospital Español en 2009. Resultados. Caso 1: Paciente masculino de 70 años, con hemiparesia izquierda y lúcido que después de la evacuación de un hematoma subdural sufrió una hemorragia sobre las folias cerebelosas y presentó hematoma vermiano de 2,5 cm a las 72 horas de la cirugía. La evolución fue desfavorable con un súbito déficit neurológico e insuficiencia cardiorrespiratoria. Caso 2: Paciente femenino de 40 años, con un hematoma vermiano asintomático de 1 cm encontrado en la TAC de control a las 72 horas de la cirugía. Evolución sin déficit neurológico. Conclusión. La cirugía supratentorial con pérdida abundante de LCR sería el factor más importante de esta complicación. El hiperdrenaje de LCR produce relajación del cerebelo con la consiguiente tracción y rotura de las venas puente que van a la tienda, provocando hematomas subdurales e infartos venosos hemorrágicos del cerebelo. Estos dos casos reportados fueron operados sin drenaje subdural aspirativo con pérdida abundante de LCR durante 72 y 48 horas respectivamente, que es el patrón etiológico más frecuente según la mayoría de los autores.

Objective. To analyze the anatomical and semiological features of the syndrome of the SMA throgh 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 posoperative status was of a right CB plejia with severe apathy and abulia with right spatial hemineglect and hypofluent and anomic languaje, with preserved repetition and comprehension. Total recovery of paresis and languaje except when stressed. Discussion. The SMA is limited by cingulate cortex inferiorly, PMC posteriorly, and vértex superiorly. 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 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 déficit, with secuelar difficulty for the fine movements of hands an a quick recuperation (days to weeks). Conclussion. The síndrome 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. Recovery is complete in a short period of time.

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 and method. Age, sex, way of presentation, location, radiologic features, surgical technique and complications 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 occlussion 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, specially 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.

Objective: to present our experience in the management of olfactory groove meningiomas analysing their clinical presentation, radiological features, surgical outcomes and postoperative complications. Methods: a retrospective study was conducted by analysing the charts of the patients including surgical records, imaging studies and histopatological records. Results: a total of 304 meningiomas were operated on between 1994-2007 in our department. There were 16 patients with olfactory groove meningiomas including 9 women and 7 men. A mean age of 52,8 yr (age range 21-72 yr). The most frequent symptom was a higher function impairment ( 5 pt). Olfactory simptoms 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 demostrated. 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.