A Novel Marking Technique for Accurate Minimal Invasive Approaches in Spine Tumor Surgeries With Activated Carbon Marking.

BACKGROUND AND OBJECTIVES: To describe a novel, practical, reproducible, and effective preoperative marking technique for accurate localization of the spinal level in a series of patients with tumor lesions. METHODS: We retrospectively analyzed patients undergoing minimally invasive (MIS) surgery for spine tumors from 2016 to 2021, in which this marking technique was used. Twenty-one patients, with tumor lesions involving difficult radioscopic visualization (cervicothoracic junction or upper dorsal spine, C6-T8), were included. Tumor lesion level was previously determined with enhanced MRI in all cases. Twenty-four to forty-eight hours before surgery, computed tomography image-guided carbon marking was performed by administration of aqueous suspension of carbon with a 21-gauge needle placed resembling the MIS approach planned trajectory. During surgery, activated carbon marking was followed until reaching the final target on the bone. Next, sequential dilators and an MIS retractor were placed. Then, bone resection and tumor exeresis were performed according to the case. RESULTS: Average age was 60.6 years (26-76 years). Fifteen (71%) patients were women. In most cases (76%), tumor pathology involved intradural lesions (meningiomas and schwannomas). In all cases, the marking described allowed to accurately guide the MIS approach to tumor site. Neither intraoperative fluoroscopy nor approach enlargement was required in any procedure. Postoperative complications were reported in only 4 patients, none related with the marking. CONCLUSION: Computed tomography image-guided activated carbon marking allows to accurately lead MIS approaches in a practical, reproducible, and effective way in cases of tumors localized in regions of the spine of difficult radioscopic visualization.

Understanding the Landscape of Spinal Injections: Insights and Challenges from Latin America.

BACKGROUND: Low back pain and neck pain are primary causes of disability, with low back pain being a frequent reason for medical consultations. After conservative and pharmacological treatments, spinal injections are considered the next option. Despite multiple guidelines, spinal blocks remain controversial in terms of indication, technique, and operator, leading to considerable interinstitutional variability. The absence of regional studies in Latin America on how spinal surgeons handle spinal injections prompts the objectives of this study: to evaluate spinal surgeons' knowledge and experience, analyze techniques, and identify barriers and challenges in implementing spinal injections, including resource limitations, technology access, and training. METHODS: A cross-sectional survey was performed using a questionnaire specifically designed by the authors. RESULTS: Two hundred sixty spinal surgeons from Latin America participated and answered a 17-question questionnaire; 75% performed their own spinal blocks and they are willing to keep on learning new techniques on the field. The most frequent block, was the lumbar facet injection (80%). And the great majority (76%) used fluoroscopy in their practice. CONCLUSIONS: The study addresses a critical gap in the literature by focusing on spinal interventions in Latin America, where there is a notable lack of regional studies. The majority of the surgeons enrolled perform their own spinal injections, and they are interested in keep on learning. The findings not only contribute to the global discourse on spinal care but also offer a basis for the development of region-specific guidelines and educational initiatives.

Does Minimally Invasive Hemilaminectomy for Intradural Extramedullary Tumor Resection Prevent Postlaminectomy Kyphosis or Lordosis Loss?

BACKGROUND: Minimally invasive hemilaminectomy is a safe and effective alternative to open laminectomy for treating intradural extramedullary tumors. There are no reports of postoperative kyphosis after this approach. This study aims to determine whether performing minimally invasive spine surgery hemilaminectomy for intradural extramedullary tumors can prevent the development of postlaminectomy kyphosis (PLK) or lordosis loss. MATERIAL AND METHODS: Sixty-five patients with spinal intradural extramedullary tumors who underwent minimally invasive hemilaminectomy surgery and complete pre and postoperative radiologic imaging were included. The effect of the surgical approach on the spinal sagittal axis was assessed by comparing pre- versus postoperative segmental and local Cobb angles at different spinal levels, considering anatomical localization (cervical, thoracic, lumbar, and transition segments) and functional features (mobile, semi-rigid, and transition segments), as well as the extent of the surgical approach (1, 2, or 3 levels) and follow-up. RESULTS: None of the patients had an increase in thoracic kyphosis nor a loss of cervical or lumbar lordosis greater than or equal to 10° after undergoing the minimally invasive spine surgery hemilaminectomy approach. More than 5° of increase in kyphosis was detected on 7.4% and 11.1%, for the segmental and the local angles, respectively; meanwhile, for patients with loss of lordosis, this deviation was detected in 5.3%, for both angles. The occurrence of PLK was more common than that of lordosis loss, but mainly manifested in postoperative angle impairment of less than 5°. No significant differences were evidenced, considering the approach length. CONCLUSIONS: Hemilaminectomy represents a promising approach for preventing PLK and postlaminectomy lordosis loss following intradural extramedullary tumor resection.

Artificial Intelligence Assistance for the Measurement of Full Alignment Parameters in Whole-Spine Lateral Radiographs.

BACKGROUND: Measuring spinal alignment with radiological parameters is essential in patients with spinal conditions likely to be treated surgically. These evaluations are not usually included in the radiological report. As a result, spinal surgeons commonly perform the measurement, which is time-consuming and subject to errors. We aim to develop a fully automated artificial intelligence (AI) tool to assist in measuring alignment parameters in whole-spine lateral radiograph (WSL X-rays). METHODS: We developed a tool called Vertebrai that automatically calculates the global spinal parameters (GSPs): Pelvic incidence, sacral slope, pelvic tilt, L1-L4 angle, L4-S1 lumbo-pelvic angle, T1 pelvic angle, sagittal vertical axis, cervical lordosis, C1-C2 lordosis, lumbar lordosis, mid-thoracic kyphosis, proximal thoracic kyphosis, global thoracic kyphosis, T1 slope, C2-C7 plummet, spino-sacral angle, C7 tilt, global tilt, spinopelvic tilt, and hip odontoid axis. We assessed human-AI interaction instead of AI performance alone. We compared the time to measure GSP and inter-rater agreement with and without AI assistance. Two institutional datasets were created with 2267 multilabel images for classification and 784 WSL X-rays with reference standard landmark labeled by spinal surgeons. RESULTS: Vertebrai significantly reduced the measurement time comparing spine surgeons with AI assistance and the AI algorithm alone, without human intervention (3 minutes vs. 0.26 minutes; P < 0.05). Vertebrai achieved an average accuracy of 83% in detecting abnormal alignment values, with the sacral slope parameter exhibiting the lowest accuracy at 61.5% and spinopelvic tilt demonstrating the highest accuracy at 100%. Intraclass correlation analysis revealed a high level of correlation and consistency in the global alignment parameters. CONCLUSIONS: Vertebrai's measurements can accurately detect alignment parameters, making it a promising tool for measuring GSP automatically.

Navigating the Indeterminate Zone: Surgeons' Decision-Making Factors in Treating Vertebral Metastases with Spinal Instability Scores of 7-12.

BACKGROUND: The Spinal Instability Neoplastic Score (SINS) classification system is a validated and the most widely accepted instrument for defining instability in vertebral metastasis (VM), in which lesions scoring between 7 and 12 are defined as indeterminate and the treatment is controversial. This study aimed to determine which variables more frequently are considered by spine surgeons for choosing between the conservative and the surgical treatment of VMs among patients with an indeterminate SINS. METHODS: A single-round online survey was conducted with 10 spine surgeons with expertise in the management of VMs from our AO Spine Region. In this survey, each surgeon independently reviewed demographic and cancer-related variables of 36 real-life cases of patients with vertebral metastases scored between 7 and 12 in the SINS. Bivariate and multivariate analyses were performed to identify significant SINS and non-SINS variables influencing the decision-making on surgical treatment. RESULTS: The most commonly variables considered important were the SINS element "mechanical pain", rated important for 44.4% of the cases, "lesion type" for 36.1%, and "degree of vertebral collapse" and the non-SINS factor "tumor histology" rated for 13.9% of cases. By far the factor most commonly rated unimportant was "posterior element compromise" (in 72.2% of cases). CONCLUSIONS: Surgeons relied on mechanical pain and type of metastatic lesion for treatment choices. Vertebral collapse, spinal malalignment, and mobility were less influential. Spinal mobility was a predictor of surgical versus non-surgical treatment. The only variables not identified either by surgeons themselves or as a predictor of surgery selection was the presence/degree of posterolateral/posterior element involvement.

Rara presentación de un linfoma espinal: informe de caso y diagnóstico mediante resonancia magnética / Rare presentation of a spinal lymphoma: case report and diagnosis by magnetic resonance imaging

El linfoma primario del sistema nervioso central es una forma de enfermedad extraganglionar originada en el cerebro, la leptomeninges, la médula espinal o los ojos. Los tumores espinales son neoplasias de baja prevalencia y pueden causar una morbimortalidad neurológica considerable. El linfoma aislado que surge dentro del conducto dural es la forma menos común de linfoma primario del sistema nervioso central: representa aproximadamente el 1% de los casos y se observa más a menudo en el contexto de diseminación secundaria que como el sitio primario de origen. Los síntomas son inespecíficos y dependen del nivel espinal involucrado. La presentación es insidiosa e incluye dorsalgia, debilidad y dificultad progresiva para la deambulación. La resonancia magnética es la modalidad de elección para búsqueda de lesiones dentro del conducto espinal/raquídeo, en pacientes que presentan síntomas neurológicos. El tratamiento quirúrgico no resulta útil, y el objetivo principal de la cirugía es conocer el diagnóstico histológico. (AU)

A primary central nervous system lymphoma is a form of extranodal disease originating in the brain, leptomeninges, spinal cord, or eyes. Spinal tumors are low-prevalence neoplasms and can cause considerable neurological morbidity and mortality. An isolated lymphoma emerging within the dural canal is the rarest form of primary central nervous system lymphoma: it accounts for approximately 1% of cases occurring more often in the context of secondary dissemination than as the primary site of origin. Symptoms are nonspecific and depend on the spinal level involved. The presentation is insidious and includes dorsalgia, weakness, and progressive difficulty in ambulatory function. MRI is the modality of choice to search for lesions within the spinal/rachial canal in patients presenting with neurological symptoms. Surgical treatment is not helpful, and the main objective of surgery is to know the histological diagnosis. (AU)

Neurocirugía en época de COVID-19. Protocolo de actuación / Neurosurgery in the time of COVID-19. Action protocol

El manejo de pacientes debido a la aparición del nuevo coronavirus 2019 (COVID-19) representa un desafío para los equipos médicos y quirúrgicos, ya que modificó el funcionamiento de los sistemas de salud en casi todo el mundo. Para contribuir a la re organización del sistema de salud, el Servicio de Neurocirugía del Hospital Italiano de Buenos Aires trabajó en adoptar distintas medidas en concordancia con las tomadas a nivel institucional y nacional; por lo que se analizó la bibliografia publicada, asi como las normas dictadas por el comité de crisis de nuestra institucion. A su vez realizamos una breve encuesta dirigida a neurocirujanos de america latina para conocer como se manejaban actualmente en relación a niveles de protección y realización de cirugias. La actual pandemia de COVID-19 es el mayor desafío que enfrentan los sistemas nacionales de salud en los últimos tiempos. Los neurocirujanos podemos contribuir a la reducción del riesgo de infección nosocomial de los trabajadores de la salud al adaptar distintos protocolos en pacientes con COVID-19.

Patient's management due to the appearance of new coronavirus 2019 (COVID-19) represents a challenge for medical and surgical departments, since it modified the running of health systems in almost all the world. In order to help in this new situation, the Neurosurgical Department of our institution has adopted different measures in accordance with those taken at institutional and national level. In order to do this, we made a literature review and we added to this, the norms dictated by the crisis committee of our hospital. We also carried out a brief survey among neurosurgeons from Latin America to find out how they managed protection levels in relation to surgery. COVID-19 pandemic is certainly one of the greatest challenge national health systems face in a century. Adapting different protocols in neurosurgical patients with COVID-19 can contribute in reducing the risk of nosocomial infection of health workers.

Cirugía mínimamente invasiva en el tratamiento de fracturas tóracolumbares / Minimally invasive surgery in the treatment of thoracolumbar fractures

Objetivo: Analizar y describir una serie de fracturas tóraco-lumbares traumáticas tratadas con cirugía mínimamente invasiva. Material y métodos: Analizamos una serie de 26 pacientes con fracturas traumáticas tóraco-lumbosacras entre 2010-2017. Las imágenes pre-operatorias fueron clasificadas usando la clasificación AO. Analizamos en forma pre y post operatoria: escala visual analógica, volumen de pérdida sanguínea, duración de la hospitalización, complicaciones, cirugías asociadas en otros órganos, extracción de implantes en el largo plazo, estado neurológico pre y post quirúrgico y mortalidad.Los pacientes con historias clínicas completas, TAC pre-operatoria y un seguimiento mínimo de 12 meses fueron incluidos (18 hombres y 8 mujeres). La edad promedio fue de 28.7 años (21-84 años); seguimiento promedio de 28 meses (13-86 meses). Dieciocho pacientes fueron manejados con instrumentaciones percutáneas, 8 recibieron vertebroplastias, y en 5 casos se realizó además algún gesto de artrodesis. Resultados: La EVA mejoró 7 puntos promedio respecto al pre-operatorio; el promedio de sangrado fue de 40 mL, no observamos ningún caso de empeoramiento neurológico. La duración promedio de la hospitalización fue de 3.9 días. Cuatro enfermos necesitaron alguna cirugía en otro órgano producto de sus politraumatismos.Los tornillos percutáneos fueron removidos en 9 casos luego de la consolidación. Como complicaciones tuvimos: 1 hematoma retroperitoneal autolimitado, una fractura pedicular y una cánula de cementación rota adentro de un pedículo. Conclusión: La cirugía mínimamente invasiva en trauma espinal es una alternativa válida que permite estabilización, movilización precoz y logra buenos resultados en términos de control del dolor con baja tasa de complicaciones

Objective: To analyze and describe a series of trauma-related thoraco-lumbo-sacral vertebral fractures managed with minimally invasive surgery. Methods: We retrospectively review the charts and images of 26 patients with thoracolumbar spine fractures between 2010-2017. Pre-op images were assessed and fractures were classified according to the thoraco-lumbar trauma AO Spine classification. We analyzed pre and post-surgical visual analog scale (VAS), blood loss during surgery, hospital length of stay, complications, associated surgical procedures, long term post-op implant removal, pre and post neurological status and mortality.Patients with a complete case record, pre-op CT scans and minimum 12-month follow up were included (18 males and 8 females). Mean age was 28.7 years (21-84 years); mean post-op follow up was 28 month (13-86 months). Eighteen patients were managed with percutaneous instrumentation, 8 patients also received percutaneous vertebroplasty, and 5 patients underwent also some arthrodesis procedure. Results: VAS improved 7 points as compared to the pre-op score; mean blood loss was 40 mL, we did not observed any neurological deficit worsening. Mean hospital length of stay was 3.9 days. Four patients needed surgical procedures involving other organs due to politrauma. Percutaneous screws were removed in 9 cases after fracture consolidation. Complications were: one case of self-limiting retroperitoneal hematoma, one case of pedicle screw fracture and one cement broken cannula into the pedicle. Conclusion: Minimally invasive surgery in spine trauma is a valid option allowing stabilization, early mobilization, and leading to good outcomes in terms of pain control and a lower complication rate

RODEXKE. Infiltración con ropivacaína, dexmedetomidina y ketorolac en cirugía espinal: Una estrategia para disminuir el consumo de opioides / RODEXKE. Infiltration with ropivacaine, dexmedetomidine, and ketorolac in spinal surgery: A strategy to decrease opioid consumption

Objetivos: Evaluar la efectividad de la infiltración del sitio quirúrgico, con ropivacaína, dexmedetomidina y ketorolac, en pacientes sometidos a instrumentación transpedicular dorsolumbar con técnica mini invasiva, en cuanto al consumo de opioides durante la internación. Materiales y métodos: Se recolectaron en forma retrospectiva los datos prospectivos de las historias clínicas de pacientes con una instrumentación con tornillos transpediculares percutáneos operados entre Junio del 2016 y Diciembre del 2018. 32 pacientes cumplieron con los criterios de selección. Se infiltró en el momento del cierre quirúrgico con una solución preparada con 150 mg de ropivacaína, 0,7 mcg/kg de dexmedetomidina y 60 mg de ketorolac, disuelto en solución fisiológica estéril para completar 40ml (Grupo M) y se la comparó con pacientes en los cuales solo se infiltró con 150mg de ropivacaína (Grupo E). Resultados: El consumo de equivalentes de morfina durante las primeras 72hs postoperatorias presentó en el grupo M una mediana de 0mg, y el grupo E, una mediana de 9,5mg (RIQ de 13,35), con una p<0,000. Por el contrario el consumo de morfina en la sala de recuperación presentó una mediana de 0mg (RIQ de 2) para el grupo M, y de 2mg (RIQ de 5) para el grupo E, sin encontrarse una diferencia significativa, p=0,132. Conclusión: Los resultados obtenidos en la comparación del consumo de opioides durante las primeras 72hs de la internación permite inferir que esta combinación de fármacos es superior respecto a la infiltración estándar con ropivacaína, independientemente de la estrategia analgésica utilizada durante el tiempo quirúrgico.

Objectives: To assess the effectiveness of a surgical site infiltration with ropivacaine, dexmedetomidine and ketorolac, in reducing opioid consumption in patients with a transpedicular dorsolumbar instrumentation using a minimally invasive technique. Materials y methods: We retrospectively collected data from patient's charts from June of 2016 to December of 2018. 32 patients with minimally invasive transpedicular dorsolumbar instrumentation, who met all criteria, were included in the analysis. During wound closure a mixture of 150mg of ropivacaine, 0,7mcg/kg of dexmedetomidine and 60mg of ketorolac, diluted in normal saline to achieve 40ml was injected (Group M). We compared them with patients in whom only 150mg of ropivacaine and saline where injected in the surgical site (Group E). Results: Morphine equivalents use during the first 72 hours postoperative had a median of 0mg for group M, and of 9,5mg (IQR of 13.35), with a p<0,000. On the contrary, morphine use during post anesthesia care unit stance had a median of 0mg (IQR of 2) for group M and of 2mg (IQR of 5) for group E, without a statistically significant difference, p=0,132. Conclusion: The result of the analysis of opioid consumption during the first 72 hours postoperative allows concluding that the infiltration of these 3 drugs together its superior to the standard infiltration with ropivacaine, independently of the analgesic strategy used during the surgery.

Abordaje mínimamente invasivo para el tratamiento de tumores espinales intradurales extramedulares / Minimally invasive approach for the treatment of extramedullary intradural spinal tumors

Introducción: Describir la técnica de abordaje mínimamente invasiva para el tratamiento de tumores intradurales extramedulares en los diferentes segmentos espinales. Material y Métodos: Se detallan la planificación, posicionamiento, marcación, pasos técnicos del abordaje mínimamente invasivo, exéresis lesional y cierre de lesiones ID-EM a nivel cervical, dorsal, lumbar y sacro. Se proporcionan recomendaciones para descomplejizar maniobras quirúrgicas, acortar el tiempo operativo y evitar potenciales complicaciones. Conclusiones: El abordaje MISS es una opción segura y eficaz para el tratamiento quirúrgico de determinados tumores ID-EM.

Objective: To describe the technique of minimally invasive approach for the treatment of intradural extramedullary tumors in the different spinal segments. Material and Methods: The planning, positioning, skin marking, technical steps of the minimally invasive approach, lesion resection, and closure of ID-EM lesions at the cervical, dorsal, lumbar and sacral levels are detailed. Recommendations are provided to simplify surgical maneuvers, shorten operative time and avoid potential complications. Conclusions: The MIS approach is a safe and effective option for the surgical treatment of certain ID-EM tumors.

Atrofia paraespinal postoperatoria. ¿El abordaje importa? / Postoperative paraspinal atrophy. Does boarding matter?

Objetivo: Comparar la magnitud de la atrofia muscular postoperatoria que producen tres abordajes en fusiones lumbares segmentarias para patología degenerativa (línea media vs. Wiltse vs. MIS TLIF). Material y métodos: Se realizó un estudio observacional, transversal, multicéntrico, descriptivo y retrospectivo, de una serie de pacientes operados por patología degenerativa lumbar. Analizamos 45 pacientes (24 mujeres), con una edad media de 58.7 años, operados en 5 centros quirúrgicos entre 2015 y 2018. Se realizó una fusión instrumentada de un nivel, desde L3 hasta S1 (7 casos L3-L4, 25 casos L4-L5 y 13 casos L5-S1). Quince casos fueron realizados por abordajes por línea media, 15 por abordaje de Wiltse y 15 MIS TLIF. Todos fueron estudiados con Resonancia Magnética preoperatoria y con un mínimo de 6 meses luego de la cirugía (media de 14.6 meses). Estas fueron analizadas por 3 observadores especialistas en cirugía de columna. Se tomaron 2 variables para comparar el grado de atrofia entre pre y postoperatorio: área de sección transversal (AST) de músculo multifidus (MM) y erectores espinales (EE) y grado de infiltración grasa (IG) mediante la clasificación visual de Kjaer. Los análisis realizados fueron ejecutados utilizando el programa estadístico RStudio (versión 1.1.383) y se compararon valores de p obtenidos mediante la suma de rangos de Wilcoxon. Resultados: No se encontraron diferencias significativas entre los distintos abordajes en relación a la atrofia del MM. La comparación de p para AST de los EE mostró diferencias entre MIS TLIF vs línea media (p 0.018) y de línea media vs Wiltse (p 0.027). Conclusión: Los abordajes mínimamente invasivos utilizados para descompresión y artrodesis monosegmentaria lumbar, tuvieron más impacto sobre la atrofia muscular en los EE que en MM. Estudios randomizados y controlados serían de utilidad para validar los resultados de este trabajo.

Aim: To compare the level of post-operative muscle atrophy associated with three different approaches to achieve segmental lumbar fusion in patients with degenerative back disease: (1) the standard midline approach; (2) Wiltse's minimally-invasive surgery (MIS-W) approach; and (3) minimal-invasive surgery (MIS) with transforaminal lumbar interbody fusion (MIS-TLIF). Methods and Materials: A multi-center, observational, cross-sectional, retrospective study was performed on a series of patients who had undergone surgery for degenerative lumbar disease. All patients were studied preoperatively and for at least six months post-operatively (mean follow-up: 14.6 months) by magnetic resonance imaging (MRI), all images analyzed by three spine-imaging specialists. Three variables were used to compare the level of atrophy before and after surgery: (1) the cross sectional area (CSA) of the multifidus muscle (MM); (2) the CSA of the spinal erector muscles (SEM); and (3) fat infiltration level, as rated per the Kjaer visual classification system. Inter-group differences in these three outcomes were assessed using Wilcoxon rank sum tests. Results: Forty-five patients (24 females), of mean age 58.7 years, underwent surgery at five participating surgical centers between 2015 and 2018. One-level instrumented fusion, from L3 to S1, was performed: at the L3-L4 level in seven patients, L4-L5 in 25, and L5-S1 in 13. Surgical access was split evenly between the three approaches, each performed in 15 patients. No significant differences were detected between the approaches, in terms of MM atrophy or fat infiltration level. Less CSA-SEM atrophy was detected with the MIS-TLIF than midline (p = 0.018), and with the MIS-W than midline (p = 0.027) approach. Conclusions: Relative to the standard midline approach, two minimally-invasive surgery approaches used for decompression and lumbar mono-segmental arthrodesis reduced atrophy in the spinal erector muscles, but not the multifidus muscle. Randomized controlled trials might be useful to validate the results of this investigation.

Resección Mínimamente Invasiva de Quistes Sinoviales Espinales. Nota Técnica / Minimally Invasive Resection of Spinal Synovial Cysts. Technical note

Objetivo: Presentar el algoritmo de tratamiento, técnica quirúrgica y resultados de una serie de pacientes con quistes sinoviales espinales resecados con técnica mínimamente invasiva (MIS). Introducción: Los quistes sinoviales espinales se originan a partir de la dilatación y potencial ruptura de la vaina sinovial de una articulación facetaria. La resección quirúrgica es considerada el tratamiento de elección en pacientes sintomáticos. La utilización de técnicas MIS podrían disminuir la disrupción de la faceta articular comprometida reduciendo el riesgo de inestabilidad postoperatoria. Material y métodos: Se evaluaron retrospectivamente 21 pacientes con quistes sinoviales espinales operados mediante abordaje y descompresión MIS, se analizaron los signos, síntomas, tiempo quirúrgico, estadía hospitalaria, evolución y complicaciones. Se utilizó la escala visual analógica (EVA), para evaluar el dolor y la escala de Weiner y los criterios de Macnab modificados para medir la satisfacción posoperatoria del paciente. Resultados: Se trataron quirúrgicamente 21 pacientes (13 mujeres, 8 hombres), el 76,2% (n=16) de los pacientes de la serie no requirió artrodesis, el 23,8% (n=5) restante fue fusionado. Realizamos 13 (61,9%) hemilaminectomías contralaterales, 7 hemilaminectomías ipsilaterales (33,3%) y una laminectomía en el QS S1-S2 con técnica MIS. El seguimiento promedio fue de 26 meses, el tiempo de cirugía fue de 150,33 ± 63,31 min., con una estadía hospitalaria de 2,5 ± 1,78 días. La EVA disminuyó de 8,3 preoperatoria a 2,3 postoperatoria. Siguiendo la escala de Macnab; 16 pacientes refirieron resultados excelentes, 4 buenos y 1 regular, el 95,2% de los pacientes percibió que el procedimiento tuvo mucho/bastante éxito según la escala de Weiner. Conclusión: El abordaje mínimamente invasivo es un procedimiento seguro y eficaz para la resección completa de quistes sinoviales espinales. Proporciona resultados clínico-funcionales excelentes preservando músculos, ligamentos y facetas articulares.

Introduction: Spinal synovial cysts originate from the dilation and potential rupture of a facet joint's synovial sheath. Surgical resection is considered the treatment of choice in symptomatic patients; however, the use of minimally-invasive surgery (MIS) techniques could reduce any disruption of the facet joint involved, reducing the risk of postoperative instability. Objective: To present the treatment algorithm, surgical technique and results in a series of patients with spinal synovial cysts treated by MIS. Methods and Materials: We retrospectively evaluated 21 patients with spinal synovial cysts who underwent therapeutic MIS with decompression. Signs, symptoms, surgical time, hospital stay, course and complications were evaluated. A visual analog scale (VAS) was used to rate pain, while the Weiner scale and modified Macnab criteria were employed to measure patients' postoperative satisfaction. Results: Twenty-one patients were surgically treated with MIS, among whom 76.2% (n = 16) required no arthrodesis; the remaining 23.8% (n = 5) were fused. We performed 13 (61.9%) contralateral hemilaminectomies, seven ipsilateral hemilaminectomies (33.3%), and one laminectomy at S1-S2. The average follow-up was 26 months, surgical time 150.33 ± 63.31 minutes, and mean hospital stay 2.5 ± 1.8 days. The VAS pain rating decreased from 8.3 preoperatively to 2.3 postoperatively. Sixteen patients reported excellent results, four good and one fair. On the Macnab scale, all but one patient (1/21, 4.8%) perceived that the procedure had been very/quite successful. Conclusions: Minimally-invasive surgery is a safe and effective approach for the complete resection of spinal synovial cysts. It provides excellent clinical and functional results, by preserving muscles, ligaments and facet joints.

Utilidad de la cirugía espinal mínimamente invasiva (MISS) en el manejo de las metástasis espinales toraco-lumbares / Utility of minimally invasive spinal surgery (MISS) in the management of thoraco-lumbar spinal metastases

Objetivo: Describir los resultados quirúrgicos y evolución de pacientes con metástasis espinales toraco-lumbares operadas con técnica mínimamente invasiva (MISS) utilizando para la decisión terapéutica la evaluación: Neurológica, Oncológica, Mecánica y Sistémica (NOMS). Material y Métodos: Se incluyeron en forma prospectiva pacientes con metástasis espinales toraco-lumbares operados con técnica MISS por el Servicio de Neurocirugía del Hospital Italiano de Buenos Aires, entre junio de 2014 y junio de 2017. Se utilizó en todos los casos el algoritmo de evaluación NOMS para la decisión terapéutica. Se analizaron los resultados quirúrgicos postoperatorios como el Karnofsky Performance Status (KPS), dolor (VAS: Visual Analogue Scale), Frankel, pérdida sanguínea, necesidad de transfusiones, complicaciones, uso de opioides y días de internación. Se consideró como estadísticamente significativo una p<0,05. Resultados: Durante el período de estudio 26 pacientes cumplieron los criterios de inclusión, de los cuales 13 fueron mujeres. La edad promedio fue 57 (27-83) años. El origen más frecuente de las lesiones fue cáncer de mama (27%). El síntoma más constante fue el dolor (96%), aunque 12 pacientes manifestaron inicialmente mielopatía (46%). Se observaron grados avanzados de invasión del canal con requerimiento de descompresión en el 65% de los casos. Acorde al Spinal Instability Neoplastic Score (SINS), 23 pacientes (89%) presentaron lesiones potencialmente inestables o inestables, requiriendo estabilización. Se evidenció una mejoría estadísticamente significativa del VAS en el 77% y del Frankel en el 67% de los casos tras la cirugía. No hubo necesidad de transfusiones. Se registró sólo una complicación quirúrgica leve (4%). La media de internación fue de 5,5 días. Conclusión: En nuestra serie y utilizando como algoritmo terapéutico el NOMS, la cirugía MISS resultó efectiva tanto para la descompresión para la estabilización espinal, con baja tasa de complicaciones y rápida recuperación postoperatoria.

Objective: To describe the surgical results and evolution of patients who undergo minimally-invasive spinal surgery (MISS) to treat thoracolumbar metastases, using the NOMS (Neurological, Oncological, Mechanical, Systemic) assessment tool to aid therapeutic decisions. Methods: Patients who underwent MISS to treat thoracolumbar metastases were prospectively enrolled at the Hospital Italiano de Buenos Aires, from June 2014 to June 2017. In all cases, the NOMS assessment tool was employed for therapeutic decision-making. Surgical results were analyzed, in terms of improvements in Karnofsky Performance Status (KPS), pain severity (VAS), and the Frankel neurological scale; also measured were blood loss and the need for transfusions, complications, use of opioids, and the length of hospitalization. P values <0.05 were considered statistically significant. Results: Twenty-six patients were enrolled (13 women) of mean age 57 years old (27-83). Breast cancer was the most frequent primary tumor (27%). The main presenting symptom was pain (96%), although 12 patients presented with myelopathy (46%). High-grade epidural spinal cord compression requiring decompression was observed in 17 patients (65%). According to the SINS (Spinal Instability Neoplastic Score), most lesions were either potentially unstable or unstable (89%), requiring stabilization. After surgery, pain severity and neurological status improved significantly in 77% and 67% of patients, respectively, with low intraoperative blood loss and no need for transfusions. Only one minor surgical complication occurred (4%). The average hospital stay was 5.5 days. Conclusion: In our series, using the NOMS instrument as the therapeutic algorithm, MISS was effective for spinal decompression and stabilization, with a low rate of complications and rapid postoperative recovery.

Biopsia estereotáctica cerebral guiada tomográficamente: Análisis de una serie de 192 casos / Tomographically guided stereotactic brain biopsy: Review of a series of 192 cases

Objective. Stereotactic CT-guided biopsy is a safe procedure for the diagnosis of brain lesions unsuitable for surgical treatment because of their location, number, histology or poor medical status. The objective of this study is to analyze the indications,demography, topography, anatomopathologic diagnosis and complications in a series of stereotactic CT-guided brain biopsies. Method. 192 CT assisted stereotactic brain biopsies in 186 patients were retrospectively reviewed from june 1998 to june of 2008. Results. 186 patients, 101males (54.3%) and 85 females (45.7%), were analyzed. Mean age was 54.5 years. 144 (75%) of the biopsies were performed in hemispheric lesions, 43 (22.4%) in “deep seated” localization. The most frequent anatomopathologic diagnosis were glioblastoma (36,5%) and anaplasic astrocytoma (17%). 90,62% of the biopsies were positive, 7,3% were negative and 2,08% nondiagnostic. Morbility rate was 3,64% and mortality 2,08%. Conclusion.Stereotactic brain biopsy is a safe and effective procedure providing tissue for definitive anatomopathological diagnosis; it offers low morbidity and mortality rate. Our findings are similar to the literature.

Hemangioma capilar medular: Reporte de un caso y revisión de la literatura / Spinal cord capillary hemangioma: Report of a case and bibliographical review

Objective. To describe a rare case of intramedullary capillary haemangioma of the thoracic spinal cord asociated with extensive cord edema and review of the literature. Description. A 65-yeard-old male pacient presented a 4-months history of dorsal back pain, progressive 4/5 paraparesis and sensory abnormality of the lower extremities. MR studies of the thoracic spine show a well-defined intramedullary mass at the D6 level, isointense on T1, hiperintense on T2 and homogeneous, strong enhancement with gadolinium, compatible with vascular lesion, asociated with extensive cord edema from D8-C2. Intervention. A D6-D7 laminectomy was performed and the tumor was completly removed en bloc by using standard microneurosurgical technique. Conclusion. It is very important to know about the existence of intramedullary capillary haemangiomas. Despite of being extremely rare, they are benign vascular neoplasms with a good outcome after their complete resection. Therefore, it´s necessary to distinguish them of other malignant tumors, to avoid overtreatment of these benign lesions.

Tratamiento quirúrgico de la neuralgia del trigémino: Experiencia en 10 años / Surgical treatment of trigeminal neuralgia: A 10 years experience

Introduction. Surgical treatment of trigeminal neuralgia remains a matter of debate since there are no studies comparing long term effectiveness of the different surgical techniques. We present our 10 year experience. Description. Series: 40 patients. Period: 1998 - 2008. Surgical techniques: microvascular decompression, radiofrequency thermorhizotomy and balloon compression. Analyzed parameters: age, sex, nerve root involved, pain relief, recurrence, complications, need to restart medication and reintervention. Discussion. Microvascular decompression offers better long term results, radiofrequency is adequate for special cases (higher recurrence rate), and balloon compression is better for V1 neuralgia. Our sample is too small for statistics, yet our findings are coincident with the literature. Conclusion. Better patient selection criteria for each technique are needed. Microvascular decompression should be the treatment of choice when possible. How to treat recurrence remains unanswered.

Neurofibromatosis segmentaria fronto temporo orbitaria: reporte de un caso: Revisión de la literatura / Fronto temporo orbitary segmental neurofibromatosis: Report of one case

Objective. To report a case of segmental neurofibromatosis located in the fronto temporal orbitary region. Description. A 54 year-old patient with a right progressive exoftalmos due to a tumor inside the orbit. He was operated 18 years ago with an histopatology diagnosis of neurofibroma. He recovered well from the surgery, but 3 years ago the right exoftalmos reappeared. The MRI shows multiple subgaleal tumors located in the right fronto temporal area, inside and outside the orbit. Intervention. A right fronto orbitary craniotomy was performed with the resection of soft non encapsulated subgaleal lesions. Conclusion. Segmental neurofibromatosis is a rare affection wich is very difficult to deal with, because of the high incidence of recurrence of the neurofibromas. Despite this, in cases like this one a surgical treatment is highly recommended to prevent not only visual defects but also cosmetic alterations.