Minimally invasive spine surgery in spinal infections.

Infections of the spine have been a constant throughout history. At present there are infections in the spine fostered in part by the same advances in medicine: there are a lot of immunocompromised patients, the life expectancy of patients with chronic diseases is augmented and the increasing number of complex spinal surgeries can result in secondary infection. In this review the main types of infection of the spine and its treatment highlighting techniques in minimally invasive surgery are discussed. Spontaneous pyogenic and nonpyogenic spine infections as well as iatrogenic infections can be treated in a different manner depending on its extension, location and microorganism involved. We will review the use and the indication of percutaneous image-guided techniques, endoscopic and microsurgical techniques with or without use of tubular retractors. We conclude that techniques in minimally invasive surgery in spine infections are safe, effective and have benefits in morbidity of the approach and subsequent patient recovery.

[Management and microsurgical treatment of infundibular dilatations of the posterior communicating artery. Series of nine cases and review of the literature]. / Manejo y traramiento microquirurgico de las dilataciones infundibulares de la arteria comunicante posterior. Seri de nueve casos y revision de la literatura.

INTRODUCTION: The infundibular dilatation (ID) of the posterior communicating (PCom) artery is defined as the conic, triangular or infundibular shaped, less than 3mm wide, origin of the PCom artery from the internal carotid artery. The purpose of this paper is to present the personal experience in the microsurgical management of the ID, to review the literature and to propose some algorithms to improve its clinical and microsurgical management. MATERIAL AND METHODS: Nine cases of ID have been operated on through a pterional approach. In four patients with subarachnoid hemorrhage (SAH) the ID was considered as the potential source of the bleeding; in four cases the ID was treated after a SAH due to the rupture of an aneurysm; finally, an ID was treated in patient with diagnosis of pseudoxantoma elasticum. RESULTS: In eight cases the ID was clipped and the Pcom artery subsequently occluded and in the remaining case the ID was associated with a fetal PComA and the ID was reinforced. There were no complications excepting a transitory third cranial nerve paresis. The Glasgow Outcome Scale was 5 in all cases at discharge and one year later. CONCLUSIONS: The true significance of the ID remains unknown, but in some instances it is necessary to consider its management: 1. In patients with ruptured aneurysms submitted to microsurgical clipping and with an ipsilateral ID, the lesion must be explored and treated; 2. In patients with ruptured aneurysms treated with endovascular procedures or harbouring an ID contralateral to a microsurgically treated aneurysm, the microsurgical indication will be done after considering all risk factors; 3. In patients with SAH and an ID as the only potential source of the bleeding there would be an indication for microsurgical exploration; 4. The incidental finding of an ID should be indication for observation in absence of major risk factors.

Manejo y tratamiento microquirúrgico de las dilataciones infundibulares de la arteria comunicante posterior. Serie de nueve casos y revisión de la literatura / Management and microsurgical treatment of infun-dibular dilatations of the posterior communicating artery. Series of nine cases and review of the literature

Introducción. La dilatación infundibular (DI) de la arteria comunicante posterior (AComP) se define como la dilatación cónica, triangular o en forma de embudo, menor de 3 mm, en el origen de la AComP de la arte­ria carótida interna. El propósito del presente trabajo es presentar la experiencia propia en el tratamiento microquirúrgico de la DI de la AComP, revisar la biblio­grafía y proponer algoritmos para optimizar su manejo clínico y microquirúrgico. Material y métodos. Se han estudiado nueve casos de DI intervenidos a través de un abordaje pterional. En cuatro pacientes con hemorragia subaracnoidea (HSA) la DI se consideró la única causa del sangrado; en otros cuatro pacientes la DI se intervino tras una HSA por ruptura de otra lesión aneurismática; finalmente, en un paciente con pseudoxantoma elástico la DI se intervino de forma preventiva. Resultados. En ocho casos se procedió al clipaje de la DI y cierre de la AComP y en uno al reforzamiento de la DI al tratarse de una AComP del tipo fetal. No aparecie­ron complicaciones salvo una paresia transitoria del III par. El Glasgow Outcome Scale al alta y al año fue de 5 en todos los casos. Conclusiones. La DI de la AComP es una lesión de significado no aclarado, pero que plantea la necesidad de considerar su tratamiento en algunas ocasiones: 1. En pacientes con aneurismas rotos sometidos a cirugía y DI homolateral se recomienda explorar y tratar la lesión; (..) (AU)

Introduction. The infundibular dilatation (ID) of the posterior communicating (PCom) artery is defined as the conic, triangular or infundibular shaped, less than 3mm wide, origin of the PCom artery from the internal carotid artery. The purpose of this paper is to present the personal experience in the microsurgical manage­ment of the ID, to review the literature and to propose some algorithms to improve its clinical and microsurgi­cal management. Material and methods. Nine cases of ID have been operated on through a pterional approach. In four patients with subarachnoid hemorrhage (SAH) the ID was considered as the potential source of the bleeding; in four cases the ID was treated after a SAH due to the rupture of an aneurysm; finally, an ID was treated in patient with diagnosis of pseudoxantoma elasticum. Results. In eight cases the ID was clipped and the Pcom artery subsequently occluded and in the remai­ning case the ID was associated with a fetal PComA and the ID was reinforced. There were no complications excepting a transitory third cranial nerve paresis. The Glasgow Outcome Scale was 5 in all cases at discharge and one year later. Conclusions. The true significance of the ID remains unknown, but in some instances it is necessary to con­sider its management: 1. In patients with ruptured aneurysms submited to microsurgical clipping and with an ipsilateral ID, the lesion must be explored and treated; 2. In patients with ruptured aneurysms treated with endovascular procedures or harbouring an ID contralateral to a microsurgically treated aneurysm, the microsurgical indication will be done after conside­ring all risk factors; 3. In patients with SAH and an ID as the only potential source of the bleeding there would be an indication for microsurgical exploration; 4. The incidental finding of an ID should be indication for (..) (AU)

[Treatment of intrinsic brain tumors located in motor eloquent areas. Results of a protocol based in navigation, tractography and neurophysiological monitoring of cortical and subcortical structures]. / Tratamiento de los tumores cerebrales intrínsecos de áreas motoras elocuentes. Resultados de un protocolo basado en la navegación, tractografía y monitorización neurofisiológica de estructuras corticales y subcorticales.

OBJECTIVES: The role of the microsurgical management of intrinsic brain tumors is to maximize the volumetric resection of the tumoral tissue minimizing the postoperative morbidity. The purpose of our paper has been to study the benefits of an original protocol developed for the microsurgical treatment of tumors located in eloquent motor areas where the navigation and electrical stimulation of motor subcortical pathways have been implemented. MATERIALS AND METHODS: A total of 17 patients operated on for resection of cortical or subcortical tumors in motor areas were included in the series. Preoperative planning for multimodal navigation was done integrating anatomic studies, motor functional MRI (f-MRI) and subcortical pathways volumes generated by diffusion tensor imaging (DTI). Intraoperative neuromonitorization included motor mapping by direct cortical and subcortical electrical stimulation (CS and sCS) and localization of the central sulcus using cortical multipolar electrodes and the N20 wave inversion technique. The location of all cortical and subcortical stimulated points with positive motor response was stored in the navigator and correlated with the cortical or subcortical motor functional structures defined preoperatively. RESULTS: The mean tumoral volumetric resection was 89.1±14.2% of the preoperative volume, with a total resection (≥100%) in twelve patients. Preoperatively a total of 58.8% of the patients had some motor deficit, increasing 24 hours after surgery to 76.5% and decreasing to 41.1% a month later. There was a great correlation between anatomic and functional data, both cortically and subcortically. However, in six cases it was not possible to identify the central sulcus and in many cases fMRI gave contradictory information. A total of 52 cortical points submitted to CS had positive motor response, with a positive correlation of 83.7%. Also, a total of 55 subcortical points had positive motor response, being in these cases 7.3±3.1 mm the mean distance from the stimulated point to the subcortical tract. CONCLUSIONS: The integration of preoperative and intraoperative anatomic and functional studies allows a safe functional resection of the brain tumors located in eloquent areas, compared to the tumoral resection based on anatomic imaging studies. Multimodal navigation allows the integration and correlation among preoperative and intraoperative anatomic and functional data. Cortical motor functional areas are anatomically and functionally located preoperatively thanks to MRI and fMRI and subcortical motor pathways with TDI and tractography. Intraoperative confirmation is done with CS and N20 inversion wave for cortical structures and with sCS for subcortical pathways. With this protocol we achieved a mean of 90% of volumetric resection in cortical and subcortical tumors located in eloquent motor areas with an increase of neurological deficits in the immediate postoperative period that significantly decreased one month later. Ongoing studies will define the safe limits for functional resection taking into account the intraoperative brain shift. Finally, it must be demonstrated if this protocol has any benefit for patients concerning disease free or overall survival.

Tratamiento de los tumores cerebrales intrínsecos de áreas motoras elocuentes. Resultados de un protocolo basado en la navegación, tractografía y monitorizaciónneurofisiológica de estructuras corticales y subcorticales / Treatment of intrinsic brain tumors located in motor eloquent areas. results of a protocol based in navegation, tractography and neurophysiological monitoring of cortical and subcortical structures

Objetivos. El papel actual del tratamiento microquirúrgicode los tumores cerebrales intrínsecos se basaen alcanzar la máxima resección volumétrica del tumorminimizando la morbilidad postoperatoria. El propósitodel trabajo es estudiar los beneficios de un protocolodiseñado para tratar tumores localizados en áreaselocuentes motoras, en el que se incluye la navegación yla estimulación de tractos motores subcorticales.Material y métodos. Se han incluido 17 pacientescon tumores corticales y subcorticales de área motoratratados quirúrgicamente. Para la planificación preoperatoriase fusionaron en el sistema de navegaciónestudios anatómicos, de resonancia funcional motora(RNM-f) y los tractos subcorticales generados porestudios de tensor de difusión (DTI). La monitorizaciónintraoperatoria incluía el mapeo motor por estimulacióncortical y subcortical directa (ECD y EsCD) e identificacióndel surco central por inversión de la onda N20con electrodos corticales multipolares. La localizaciónde los puntos con respuesta positiva a la ECD o EsCD secorrelacionaba con las áreas corticales o tractos funcionalesmotores definidos en los estudios preoperatoriosgracias al navegador.Resultados. La resección volumétrica tumoral mediafue del 89.1±14.2% del volumen tumoral calculado enlos estudios preoperatorios, con resección total (≥100%)en doce pacientes. En el preoperatorio había focalidadneurológica deficitaria motora en el 58.8% de lospacientes, que aumentó al 76.5% a las 24 horas de lacirugía y se redujo a los 30 días al 41.1%. Hubo una (..) (AU)

Objectives. The role of the microsurgical managementof intrinsic brain tumors is to maximize the volumetricresection of the tumoral tissue minimizing thepostoperative morbidity. The purpose of our paper hasbeen to study the benefits of an original protocol developedfor the microsurgical treatment of tumors locatedin eloquent motor areas where the navigation and electricalstimulation of motor subcortical pathways havebeen implemented.Materials and methods. A total of 17 patients operatedon for resection of cortical or subcortical tumors inmotor areas were included in the series. Preoperativeplanning for multimodal navigation was done integratinganatomic studies, motor functional MRI (f-MRI)and subcortical pathways volumes generated by diffusiontensor imaging (DTI). Intraoperative neuromonitorizationincluded motor mapping by direct corticaland subcortical electrical stimulation (CS and sCS) andlocalization of the central sulcus using cortical multipolarelectrodes and the N20 wave inversion technique.The location of all cortical and subcortical stimulatedpoints with positive motor response was stored in thenavigator and correlated with the cortical or subcorticalmotor functional structures defined preoperatively.Results. The mean tumoral volumetric resection (..) (AU)

[Using thermal diffusion flowmetry in the assesment of regional cerebral blood flow in cerebral aneurysm microsurgery]. / Flujometría por difusióón termal para la medida del flujo sanguíneo cerebral regional en la cirugía de los aneurismas cerebrales.

INTRODUCTION: the thermal diffusion flowmetry (TDF) is a technique that allows the measurement of the regional cerebral blood flow (rCBF) through an implanted microprobe in a cerebral region of interest. The monitoring is continuous, real-time and quantitative (ml/100g/min). The purpose of our clinical work has been to show the technical details and preliminary results by using this monitoring technique during the microsurgical management of cerebral aneurysms and along the postoperative period. The aim of the monitoring of the rCBF is to identify and evaluate ischemic events related with the temporary artery clipping or malposition of the final clip. CLINICAL MATERIALS: a total of five patients have been monitored (4 woman and one man with an average age of 50.8 years). Two patients harboured one aneurysm in the middle cerebral artery, other two patients had two aneurysms each one on the internal carotid artery in the exit of the posterior communicating and anterior choroidal artery and the fifth harboured a paraclinoid internal carotid artery aneurysm. All patients were operated on using standard microsurgical techniques through a pterional approach. Surgery was done under neurophysiological monitoring and direct microdoppler fluometry assesment. Just before craniotomy the TDF microprobe was inserted 2.5 cm deep into the white matter through a small burr-hole placed on the coronal line and 2 cm away the midline to measure in the anterior cereral artery vascular sector and 6cm away of the midline to measure in the middle cerebral artery territory. Patients were under continuous monitoring during surgery and along the postoperative period in the recovery unit. A total of 14 temporary artery clippings (between 2-4) with an average total clipping time of 7.2 minutes (ranging 1.6 to 16) and 16 definitive clip replacements (ranging 2 to 8) were done at surgery. Patient with paraclinoid aneurysm was operated on using the retrograde aspiration technique and the internal carotid artery was kept closed 45 mimutes. keeping Some illustrative cases and demonstrative records are presented. CONCLUSIONS: the use of TDF allows a quantitative real-time measurement of the rCBF in the areas of interest monitored during the microsurgical management of the cerebral aneurysms which leads to detect ischemic events helpping to avoid ischemic sequelae. The detection of ischemic events in real time would make possible the use of therapeutic measures ealier and more efficienty.

Flujometría por difusión termal para la medida del flujo sanguíneo cerebral regionalen la cirugía de los aneurismas cerebrales / Using thermal diffusion flowmetry in the assesment of regional cerebral blood flow in cerebral aneurysm microsurgery

Introducción. La flujometría por difusión termal(FDT) es una técnica que permite, mediante la implantación de una microsonda en una región cerebral de interés, determinar el flujo sanguíneo cerebral regional (FSCr) y su monitorización cuantitativa (ml/100g/min), continua y en tiempo real. El objetivo de nuestro trabajo es mostrar los detalles técnicos y resultados preliminares de esta técnica de monitorización durante la cirugía y el postoperatorio del tratamiento microquirúrgico de los aneurismas cerebrales, donde tendría valor para detectar y cuantificar fenómenos isquémicos relacionados con el clipaje temporal arterial o malposición del clip definitivo. Material clínico. Han sido monitorizados cinco pacientes(4 mujeres y 1 hombre; edad media de 50.8 años),dos de ellos con aneurismas de arteria cerebral media, otros dos con sendos aneurismas de arteria comunicante posterior y coroidea anterior y uno con aneurisma de carótida interna paraclinoideo. Los pacientes fueron intervenidos con técnica microquirúrgica y clipaje de los aneurismas a través de un abordaje pterional. Se utilizó monitorización neurofisiológica peroperatoria y flujometría con microdoppler. Inmediatamente antes de la craneotomía se procedió a la colocación de la microsonda de FDT a través de un minitrépano sobrela línea coronal, en territorio de la arteria cerebral anterior (2 cm de línea media) o de la cerebral media(6 cm de línea media) y en sustancia blanca, a unos 2.5cm de profundidad. Los pacientes fueron monitorizados durante la cirugía y el tiempo en que estuvieron en la Unidad de Reanimación. Se realizaron un total de 14 clipajes temporales (rango 2-4) con un tiempo medio de clipaje de 7.2 min (rango 1.6-16) (..) (AU)

Introduction. The thermal diffusion flowmetry(TDF) is a technique that allows the measurement of the regional cerebral blood flow (rCBF) through an implanted microprobe in a cerebral region of interest.The monitoring is continuous, real-time and quantitative(ml/100g/min). The purpose of our clinical work has been to show the technical details and preliminary results by using this monitoring technique during the microsurgical management of cerebral aneurysms and along the postoperative period. The aim of the monitoring of the rCBF is to identify and evaluate is chemicevents related with the temporary artery clipping or malposition of the final clip.Clinical materials. A total of five patients have been monitored (4 woman and one man with an average age of 50.8 years). Two patients harboured one aneurysm in the middle cerebral artery, other two patients had two aneurysms each one on the internal carotid artery in the exit of the posterior communicating and anterior choroidal artery and the fifth harboured a paraclinoid internal carotid artery aneurysm. All patients were operated on using standard microsurgical techniques through a pterional approach. Surgery was done under neurophysiological monitoring and direct microdoppler fluometry assesment. Just before craniotomy the TDF micropro be was inserted 2,5 cm deep into the white matter through a small burr-hole placed on the coronalline and 2 cm away the midline to measure in the anterior cereral artery vascular sector and 6 cm away of the midline to measure in the middle cerebral artery territory. Patients were under continuous monitoring during surgery and along the postoperative period in the recovery unit. A total of 14 temporary artery clippings (between 2-4) with an average total (..) (AU)