[The role of diffusion tensor imaging in the pre-surgical study of temporal lobe epilepsy]. / Papel de la imagen por tensor de difusion en el estudio prequirurgico de la epilepsia del lobulo temporal.

INTRODUCTION: Diffusion tensor imaging (DTI) is a non-invasive technique that can be used to assess the integrity of the white matter in the brain. AIMS: To investigate the usefulness of DTI in patients with temporal lobe epilepsy (TLE) and to observe its relationship with lateralisation of the epileptogenic focus in these patients. PATIENTS AND METHODS: We analysed 11 patients diagnosed with TLE in accordance with the pre-surgical protocol of our epilepsy unit, and who were seizure-free two years after performing a temporal lobectomy plus amygdalohippocampectomy (Spencer technique). As part of their pre-operative study, a 1.5 T magnetic resonance brain scan with diffusion tensor imaging was performed. A voxel-based analysis was then employed to study the differences in connectivity between the hemisphere that underwent surgery and the contralateral hemisphere. RESULTS: Compared with the contralateral hemisphere, a statistically significant reduction in fractional anisotropy (p < 0.05) was observed in the corpus callosum, the cingulate, the superior longitudinal fasciculus, the anterior thalamic radiations, the internal capsule, the ventral lateral and pulvinar nuclei of the thalamus, the inferior frontooccipital fasciculus, the uncinate fasciculus, the inferior longitudinal fasciculus and the parahippocampal gyrus, all ipsilateral to the epileptogenic focus. CONCLUSIONS: The characterisation of the abnormalities in the connectivity of the cerebral white matter, by means of DTI in patients with TLE, can be a valuable aid for the lateralisation of the epileptogenic focus in the pre-surgical evaluation of these patients. Further studies with a higher number of patients would be needed to confirm these results.

TITLE: Papel de la imagen por tensor de difusion en el estudio prequirurgico de la epilepsia del lobulo temporal.Introduccion. La imagen por tensor de difusion (DTI) es una tecnica no invasiva que puede ser utilizada para evaluar la integridad de la sustancia blanca cerebral. Objetivo. Investigar la utilidad de la DTI en pacientes con epilepsia del lobulo temporal (ELT) y ver su relacion con la lateralizacion del foco epileptogeno en estos pacientes. Pacientes y metodos. Se analizan 11 pacientes diagnosticados de ELT segun el protocolo de evaluacion prequirurgica de nuestra unidad de epilepsia, y libres de crisis a los dos años de la realizacion de una lobectomia temporal mas amigdalohipocampectomia (tecnica de Spencer). Como parte de su estudio preoperatorio, se realiza una resonancia magnetica cerebral de 1,5 T con secuencia de tensor de difusion y se estudian, mediante un analisis basado en voxel, las diferencias en la conectividad entre el hemisferio intervenido y el contralateral. Resultados. Comparado con el hemisferio contralateral, se observo una reduccion de la anisotropia fraccional estadisticamente significativa (p < 0,05) en el cuerpo calloso, el cingulo, el fasciculo longitudinal superior, las radiaciones talamicas anteriores, la capsula interna, los nucleos ventral lateral y pulvinar del talamo, el fasciculo frontooccipital inferior, el fasciculo uncinado, el fasciculo longitudinal inferior y el giro parahipocampal ipsilaterales al foco epileptogeno. Conclusiones. La caracterizacion de las anormalidades en la conectividad de la sustancia blanca cerebral, a traves de la DTI en pacientes con ELT, puede tener un valor importante para la lateralizacion del foco epileptogeno en la evaluacion prequirurgica. Serian necesarios estudios con un numero mas elevado de pacientes para confirmar estos resultados.

[Frontal aneurysmal bone cyst. A case report and review of the literature]. / Quiste oseo aneurismatico frontal. Caso clinico y revision de la bibliografia.

INTRODUCTION: Cranial aneurysmal bone cyst (ABC) is a rare pathological finding that is usually diagnosed in young patients. It is defined as a benign lesion made up of intervillous spaces limited by connective bone tissue septa and osteoclast-type giant cells; these histological characteristics are common to extracranial ABC. Clinically, in most patients, they manifest as cranial tumours which may be painful and vary in size. About 100 cases of cranial ABC have been reported in the literature. We present a literature review of the cases of frontal ABC reported to date, including one that was recently treated in our own service. CASE REPORT: A 29-year-old female, with no history of traumatic brain injury, who was examined due to the presence of a fixed, painless frontal cranial lesion on the right-hand side. The results of a radiological study revealed the presence of a lytic cranial lesion with well-delimited edges and marginal sclerosis; peripheral and linear contrast enhancement was also observed in the magnetic resonance imaging of the brain. The patient was submitted to a surgical intervention and the entire lesion was removed. There were no incidents in the post-operative period and the definitive pathological diagnosis was cranial ABC. CONCLUSIONS: Cranial ABC is a pathological condition with well-defined histological and radiological characteristics, despite the fact that its aetiopathogenesis is still not fully understood. Complete excision of the tumour is considered to be the preferred treatment, which often leads to full recovery of the patient and also offers a good long-term prognosis.

Spontaneous acute hemorrhage within a subependymoma of the lateral ventricle: successful emergent surgical removal through a frontal transcortical approach.

INTRODUCTION. Subependymomas are benign neoplasms intimately related to the ventricular system which only exceptionally associate hemorrhagic events. We present neuroradiological and pathological evidences of intratumoral hemorrhage within a single case of subependymoma operated on at our institution. Additionally we analyze retrospectively the well-defined reports of similar cases published in the scientific literature. CASE REPORT. A 71-year-old man on anticoagulant therapy presented with abrupt and progressive deterioration of his level of consciousness. Emergent computed tomography and magnetic resonance imaging evidenced signs of acute bleeding within a mass located at the frontal horn of the left lateral ventricle, producing obstructive biventricular hydrocephalus. The lesion was immediately and completely removed through a left frontal transcortical approach. Pathological diagnosis was consistent with subependymoma displaying areas of microhemorrhage. After surgery the patient developed global anterograde and retrograde amnesia. CONCLUSIONS. A spontaneous hemorrhagic event within an asymptomatic lateral ventricle subependymoma can result in a surgical emergence as a consequence of sudden obstruction of cerebrospinal fluid pathways. Prompt and radical surgical removal of the mass, which allows a rapid resolution of hydrocephalus and prevents the risk of rebleeding, may constitute the safest management strategy.

Spontaneous acute hemorrhage within a subependymoma of the lateral ventricle: successful emergent surgical removal through a frontal transcortical approach

Introduction. Subependymomas are benign neoplasms intimately related to the ventricular system which only exceptionally associate hemorrhagic events. We present neuroradiological and pathological evidences of intratumoral hemorrhage within a single case of subependymoma operated on at our institution. Additionally we analyze retrospectively the well-defined reports of similar cases published in the scientific literature. Case report. A 71-year-old man on anticoagulant therapy presented with abrupt and progressive deterioration of his level of consciousness. Emergent computed tomography and magnetic resonance imaging evidenced signs of acute bleeding within a mass located at the frontal horn of the left lateral ventricle, producing obstructive biventricular hydrocephalus.The lesion was immediately and completely removed through a left frontal transcortical approach. Pathological diagnosis was consistent with subependymoma displaying areas of microhemorrhage. After surgery the patient developed global anterograde and retrograde amnesia. Conclusions. A spontaneous hemorrhagic event within an asymptomatic lateral ventricle subependymoma can result in a surgical emergence as a consequence of sudden obstruction of cerebrospinal fluid path ways. Prompt and radical surgical removal of them ass, which allows a rapid resolution of hydrocephalus and prevents the risk of rebleeding, may constitute the safest management strategy (AU)

Introducción. Los subependimomas son neoplasias benignas que se desarrollan en estrecha relación con el sistema ventricular y que excepcionalmente asocian fenómenos hemorrágicos. Describimos el caso de un subependimoma localizado en el ventrículo lateral que presentó una hemorragia intratumoral aguda de forma espontánea, como se evidenció en los estudios neurorradiológicos y patológicos realizados, incluyendo un análisis exhaustivo de los casos similares descritos en la literatura científica. Caso clínico. Se trata de un varón de 71 años que recibía tratamiento anticoagulante, y que presentó un cuadro brusco y progresivo de disminución del nivel de conciencia. Los estudios de neuroimagen evidenciaron la presencia de una masa localizada en el ventrículo lateral izquierdo, con signos de hemorragia reciente en su seno, que producía hidrocefalia biventricular aguda. La lesión fue resecada en su totalidad de forma urgente mediante un abordaje frontal transcortical. El estudio patológico de la lesión demostró que se trataba de un subependimoma con focos hemorrágicos. En el periodopostoperatorio, el paciente presentó un déficit de memoria global, tanto anterógrada como retrógrada. Conclusiones. Los episodios de hemorragia espontánea aguda constituyen un fenómeno excepcional en el caso de los tumores de histología benigna como los subependimomas, y pueden transformar un curso clínico asintomático en una emergencia quirúrgica debido al desarrollo de hidrocefalia aguda. La extirpación completa de la lesión de forma urgente representa la opción de manejo quirúrgico más apropiada, ya que permite un reestablecimiento inmediato de la circulación de líquido cefalorraquídeo y previene la aparición de resangrado (AU)

[Reconstruction of thoracolumbar spine instability: clinical and neuroradiological results of a surgical challenge]. / Reconstrucción de la columna toracolumbar inestable: resultados clínicos y neurorradiológicos de un desafío quirúrgico.

INTRODUCTION: Surgical treatment for thoracolumbar union instability represents a challenge, due to the difficult access to this area of the spine, and to the extreme variability of morphological and biomechanical lesions observed. AIM: To describe the indications and clinical and neuroradiological results obtained with procedures of anterior or combined spinal fusion-instrumentation used for the treatment of instable thoracolumbar lesions. PATIENTS AND METHODS: 17 patients with thoracolumbar instability were treated surgically, being followed-up at least for one year. Causes of instability were classified in three groups: (i) fractures or fracture-luxations (n = 7), (ii) pathologic fractures following tumoral invasion (n = 6) and (iii) infectious or degenerative spondylodiscitis (n = 5). In order to carry out the substitution of the injured vertebral body an anterior approach to the thoracolumbar union was performed in all cases, using a modified technique of thoracophrenolaparotomy in which the diaphragmatic dome was not incised. Depending on the number of columns of Denis damaged, the vertebral corpectomy was followed by either an anterolateral or a combined spinal fusion-instrumentation. RESULTS: Pain in standing position was eliminated postoperatively in 83%. Neurological deficits were improved in 50% of cases. Surgical mortality was null and transient postoperative complications occurred in 11.7% of patients, but no lung atelectasis or respiratory infections were observed. CONCLUSIONS: Chronic pain associated to thoracolumbar instability can be treated successfully by substitution of the damaged vertebral body followed by anterior or combined spinal fusion-instrumentation. Thoracophrenolaparotomy without division of the diaphragm is feasible and it reduces the morbidity associated to postoperative respiratory complications.

Reconstrucción de la columna toracolumbar inestable: resultados clínicos y neurorradiológicos de un desafío quirúrgico / Reconstruction of thoracolumbar spine instability: clinical and neuroradiological results of a surgical challenge

Introducción. El tratamiento de la inestabilidad de la unión toracolumbar constituye un desafío quirúrgico, por el difícil acceso anatómico a este segmento vertebral y por la gran variabilidad de alteraciones morfológicas y biomecánicas existentes. Objetivo. Describir las indicaciones y los resultados clínicos y neurorradiológicos de las técnicas de fusión-instrumentación anterior o combinada, empleadas en el tratamiento de la inestabilidad toracolumbar. Pacientes y métodos. Se ha tratado quirúrgicamente a 17 pacientes con inestabilidad toracolumbar, con un seguimiento posoperatorio mínimo de un año. Las causas de inestabilidad se clasificaron en tres grupos: 1. Fracturas o fracturas-luxación de origen traumático (n = 7); 2. Fracturas patológicas por invasión tumoral vertebral (n = 6), y 3. Espondilodiscitis de origen infeccioso o degenerativo (n = 5). En todos los casos se empleó un abordaje por vía anterior a la unión toracolumbar mediante toracofrenolaparotomía sin sección de la cúpula diafragmática, con sustitución del segmento vertebral y fusión-instrumentación anterolateral o combinada según el número de columnas de Denis dañadas. Resultados. El tratamiento quirúrgico de reestabilizar la unión toracolumbar logró la desaparición del dolor en bipedestación en el 83% de los casos y mejoró el déficit neurológico en el 50%. La mortalidad quirúrgica fue nula y la morbilidad posquirúrgica del 11,7%, sin que se produjeran atelectasias pulmonares o infecciones respiratorias. Conclusiones. El tratamiento de la inestabilidad toracolumbar mediante la sustitución del cuerpo vertebral dañado y fusión-instrumentación anterior o combinada permite eliminar satisfactoriamente el dolor crónico en posición erguida. La técnica de toracofrenolaparotomía sin sección del diafragma reduce la morbilidad asociada a las alteraciones respiratorias posquirúrgicas

Introduction. Surgical treatment for thoracolumbar union instability represents a challenge, due to the difficult access to this area of the spine, and to the extreme variability of morphological and biomechanical lesions observed. Aim. To describe the indications and clinical and neuroradiological results obtained with procedures of anterior or combined spinal fusion-instrumentation used for the treatment of instable thoracolumbar lesions. Patients and methods. 17 patients with thoracolumbar instability were treated surgically, being followed-up at least for one year. Causes of instability were classified in three groups: (i) fractures or fracture-luxations (n = 7), (ii) pathologic fractures following tumoral invasion (n = 6) and (iii) infectious or degenerative spondylodiscitis (n = 5). In order to carry out the substitution of the injured vertebral body an anterior approach to the thoracolumbar union was performed in all cases, using a modified technique of thoracophrenolaparotomy in which the diaphragmatic dome was not incised. Depending on the number of columns of Denis damaged, the vertebral corpectomy was followed by either an anterolateral or a combined spinal fusion-instrumentation. Results. Pain in standing position was eliminated postoperatively in 83%. Neurological deficits were improved in 50% of cases. Surgical mortality was null and transient postoperative complications occurred in 11.7% of patients, but no lung atelectasis or respiratory infections were observed. Conclusions. Chronic pain associated to thoracolumbar instability can be treated successfully by substitution of the damaged vertebral body followed by anterior or combined spinal fusion-instrumentation. Thoracophrenolaparotomy without division of the diaphragm is feasible and it reduces the morbidity associated to postoperative respiratory complications

Subluxación atloaxoidea. “Os odontoideum”. Reducción y fijación posterior con alambres sublaminares en Cl anclados en tornillos pediculares de C2. Caso clínico / Atlanto axial dislocaton associated with os odontoideum. Reduction and fixation with sublaminar wires in CI and pedicle servew in C2. Case report

Se presenta un caso de subluxación atlo-axoidea asociada a “os odontoideum”, en un varón de 18 años con un antecedente traumático a los 2 años de edad, que padece una mielopatía crónica progresiva al borde de la supervivencia. Para la reducción y fijación de la luxación se han utilizado alambres sublaminares en Cl anclados a tornillos fijados en los pedículos de C2. Se comenta la técnica, no conociendo ningún precedente de la misma (AU)

This report describes a case of atlanto-axial disloca¬tion associated with os odontoideum. This 18-year-old male had a traumatic episode when he was 2 years old. As a result he suffered progressive chronic myelopathy on the verge of death. For the reduction and fixation of the atlanto-axial dislocation, sublaminar wires have been used anchored to Cl and to screws placed in the pedicles of C2. The authors present a surgical technique that has not been previously described (AU)

[Atlanto-axial dislocation associated with os odontoideum. Reduction and fixation with sublaminar wires in Cl and pedicle screws in C2. Case report]. / Subluxación atloaxoidea. "Os odontoideum." Reducción y fijación posterior con alambres sublaminares en C1 anclados en tornillos pediculares de C2. Caso clínico.

This report describes a case of atlanto-axial dislocation associated with os odontoideum. This 18-year-old male had a traumatic episode when he was 2 years old. As a result he suffered progressive chronic myelopathy on the verge of death. For the reduction and fixation of the atlanto-axial dislocation, sublaminar wires have been used anchored to C1 and to screws placed in the pedicles of C2. The authors present a surgical technique that has not been previously described.