Shaping the curve from the microscopic transsphenoidal to the endoscopic endonasal approach for the sellar region.

OBJECTIVE: This study aimed to investigate the limitations, barriers, and complications in the early transition from the microscopic transsphenoidal approach (MTA) to the endonasal endoscopic approach (EEA) to the skull base in our institution. METHODS: Technical challenges, as well as clinical features and complications, were compared between MTA, EEA, and mixed cases during the early surgical curve. RESULTS: The period from the early learning curve was 1 year until the EEA protocol was used routinely. A total of 34 patients registered a resection using a transsphenoidal approach. Eighteen patients underwent EEA, 11 underwent MTA, and five underwent a mixed endonasal and microscopic approach. Non-significant differences were found in endocrine outcomes between the three groups. Patients with unchanged or improved visual function were higher in the EEA group (p = 0.147). Non-significant differences were found in terms of the extent of resection (EOR) between groups (p = 0.369). Only 1 (2.9%) patient in the whole series developed a post-operative CSF leaking that resolved with medical management, belonging to the EEA group (5.5%). CONCLUSIONS: The early phase of the learning curve did not affect our series significantly in terms of the EOR, endocrine status, and visual outcomes.

OBJETIVO: Investigar las limitaciones, las barreras y las complicaciones en la transición del abordaje transesfenoidal microscópico (ATM) al abordaje endonasal endoscópico (AEE) para la base del cráneo en nuestra institución. MÉTODO: Se compararon las características clínicas y las complicaciones entre ATM, AEE y casos mixtos durante la curva quirúrgica temprana. RESULTADOS: El periodo desde la curva de aprendizaje inicial fue de 1 año hasta que se utilizó el protocolo AEE de forma sistemática. Un total de 34 pacientes tuvieron una resección por vía transesfenoidal. A 18 pacientes se les realizó AEE, a 11 ATM y a 5 abordaje mixto endonasal y microscópico. Se encontraron diferencias no significativas en los resultados endocrinos entre los tres grupos. Los pacientes con función visual sin cambios o mejorada fueron más en el grupo AEE (p = 0.147). No se encontraron diferencias significativas respecto a la extensión de la resección (p = 0.369). Solo 1 (2.9%) paciente desarrolló una fístula de líquido cefalorraquídeo que se resolvió con manejo médico, perteneciente al grupo AEE (5.5%). CONCLUSIONES: La fase inicial de la curva de aprendizaje no afectó significativamente a nuestra serie en términos de extensión de la resección, estado endocrino y resultados visuales.

Combined open maxillectomy and endoscopic endonasal resection of a giant V2 trigeminal schwannoma.

BACKGROUND: Trigeminal schwannoma is a rare type of tumor that arises from the Schwann cells of the trigeminal nerve. METHOD: We present a case of a patient with a giant V2 trigeminal schwannoma with painful swelling in the left maxilla. A complete resection using a combined open maxillectomy and endoscopic endonasal approach was performed. CONCLUSION: This case highlights the importance of a multidisciplinary approach to perform a combined open and endoscopic approach for safe resection while preserving adequate speech and swallowing.

Differential tractography and whole brain connectometry in primary motor area gliomas resection: A feasibility study.

OBJECTIVE: Establish the evolution of the connectome before and after resection of motor area glioma using a comparison of connectome maps and high-definition differential tractography (DifT). METHODS: DifT was done using normalized quantitative anisotropy (NQA) with DSI Studio. The quantitative analysis involved obtaining mean NQA and fractional anisotropy (FA) values for the disrupted pathways tracing the corticospinal tract (CST), and white fiber network changes over time. RESULTS: We described the baseline tractography, DifT, and white matter network changes from two patients who underwent resection of an oligodendroglioma (Case 1) and an IDH mutant astrocytoma, grade 4 (Case 2). CASE 1: There was a slight decrease in the diffusion signal of the compromised CST in the immediate postop. The NQA and FA values increased at the 1-year follow-up (0.18 vs. 0.32 and 0.35 vs. 0.44, respectively). CASE 2: There was an important decrease in the immediate postop, followed by an increase in the follow-up. In the 1-year follow-up, the patient presented with radiation necrosis and tumor recurrence, increasing NQA from 0.18 in the preop to 0.29. Fiber network analysis: whole-brain connectome comparison demonstrated no significant changes in the immediate postop. However, in the 1-year follow up there was a notorious reorganization of the fibers in both cases, showing the decreased density of connections. CONCLUSIONS: Connectome studies and DifT constitute new potential tools to predict early reorganization changes in a patient's networks, showing the brain plasticity capacity, and helping to establish timelines for the progression of the tumor and treatment-induced changes.

Cerebral Myiasis, An Unexpected Intraoperative Finding - A Case Report and Systematic Review.

Postoperative complications, exemplified by surgical site infections, are commonplace in the realm of daily surgical interventions. Conversely, certain infectious entities, such as cerebral myiasis (CM), are distinctly rare. This report elucidates the clinical presentation of a 74-year-old female afflicted with a CSF fistula, within the context of a preceding surgical microvascular decompression employing a suboccipital craniotomy approach. Notably, the course of evaluation and treatment unveiled an intraoperative manifestation of severe CM. This case report underscores the critical significance of prompt identification, precise diagnostic elucidation, and comprehensive multidisciplinary management to optimize patient outcomes in instances of CM. Furthermore, a systematic literature review on CM supplements this report, contributing to the understanding of this infrequent complication.

Gliomas difusos en áreas elocuentes: avances diagnósticos y terapéuticos / Diffuse gliomas within eloquent areas: diagnostic and therapeutic advances

Objetivo: presentar los avances diagnósticos, moleculares y radiológicos, así como en las estrategias terapéuticas para gliomas difusos en los últimos 5 años (2018-2023) en la Fundación Universitaria de Ciencias de la Salud (FUCS), Bogotá D.C., Colombia. Materiales y métodos: se describen las técnicas diagnósticas y terapéuticas utilizadas para gliomas difusos con casos ilustrativos. Resultados: se muestran los avances de las herramientas diagnósticas y terapéuticas para el manejo de gliomas difusos. Discusión: en los últimos 5 años se ha avanzado en la clasificación, diagnóstico y tratamiento de los gliomas difusos, gracias a los avances tecnológicos como los marcadores moleculares, la tractografía y la fusión de imágenes para la neuronavegación y las técnicas de estimulación cortical. Esto ha permitido que el tratamiento de los pacientes con dichos tumores mejore la tasa de morbilidad, la calidad de vida libre de enfermedad y la supervivencia global. Conclusiones: las técnicas de diagnóstico como la tractografía, la fusión integral de imágenes intraoperatorias y el mapeo cerebral electrofisiológico con estimulación cortical y subcortical han mejorado el diagnóstico y tratamiento de los gliomas difusos.

Objective: to present the diagnostic, molecular, radiological, and therapeutic advances, to address diffuse gliomas, made at Fundación Universitaria de Ciencias de la Salud (FUCS), Bogotá D.C., Colombia, in the last 5 years (2018-2023). Materials and methods: diagnostic and therapeutic techniques to address diffuse gliomas are described through illustrative cases. Results: the advances in diagnostic and therapeutic tools for managing diffuse gliomas, are shown. Discussion: in the last 5 years progress in characterizing, diagnosing, and treating diffuse gliomas, thanks to technological breakthroughs, such as molecular markers, tractography, image fusion for neuronavigation, and cortical stimulation techniques, has been achieved. This has allowed improving morbidity rate, disease-free quality of life and overall survival through the treatment provided to patients afflicted with gliomas. Conclusions: Diagnostic techniques based on tractography, comprehensive intraoperative image fusion, and electrophysiological brain mapping with cortical and subcortical stimulation, have improved the diagnostic and therapeutic approaches for diffuse gliomas.

Augmented reality for intracranial meningioma resection: a mini-review.

Augmented reality (AR) integrates computer-generated content and real-world scenarios. Artificial intelligence's continuous development has allowed AR to be integrated into medicine. Neurosurgery has progressively introduced image-guided technologies. Integration of AR into the operating room has permitted a new perception of neurosurgical diseases, not only for neurosurgical planning, patient positioning, and incision design but also for intraoperative maneuvering and identification of critical neurovascular structures and tumor boundaries. Implementing AR, virtual reality, and mixed reality has introduced neurosurgeons into a new era of artificial interfaces. Meningiomas are the most frequent primary benign tumors commonly related to paramount neurovascular structures and bone landmarks. Integration of preoperative 3D reconstructions used for surgical planning into AR can now be inserted into the microsurgical field, injecting information into head-up displays and microscopes with integrated head-up displays, aiming to guide neurosurgeons intraoperatively to prevent potential injuries. This manuscript aims to provide a mini-review of the usage of AR for intracranial meningioma resection.

The state of art of awake craniotomy in Latin American countries: a scoping review.

BACKGROUND AND OBJECTIVE: Awake craniotomy (AC) is a valuable technique for surgical interventions in eloquent areas, but its adoption in low- and middle-income countries faces challenges like limited infrastructure, trained personnel shortage, and inadequate funding. This scoping review explores AC techniques in Latin American countries, focusing on patient characteristics, tumor location, symptomatology, and outcomes. METHODS: A scoping review followed PRISMA guidelines, searching five databases in English, Spanish, and Portuguese. We included 28 studies with 258 patients (mean age: 43, range: 11-92). Patterns in AC use in Latin America were analyzed. RESULTS: Most studies were from Brazil and Mexico (53.6%) and public institutions (70%). Low-grade gliomas were the most common lesions (55%), most of them located in the left hemisphere (52.3%) and frontal lobe (52.3%). Gross-total resection was achieved in 34.3% of cases. 62.9% used an Asleep-Awake-Asleep protocol, and 14.8% used Awake-Awake-Awake. The main complication was seizures (14.6%). Mean post-surgery discharge time was 68 h. Challenges included limited training, infrastructure, and instrumentation availability. Strategies discussed involve training in specialized centers, seeking sponsorships, applying for awards, and multidisciplinary collaborations with neuropsychology. CONCLUSION: Improved accessibility to resources, infrastructure, and adequate instrumentation is crucial for wider AC availability in Latin America. Despite disparities, AC implementation with proper training and teamwork yields favorable outcomes in resource-limited centers. Efforts should focus on addressing challenges and promoting equitable access to this valuable surgical technique in the region.

Preoperative tractography algorithm for safe resection of tumors located in the descending motor pathways zone.

Background: Diffusion tensor imaging (DTI) tractography facilitates maximal safe resection and optimizes planning to avoid injury during subcortical dissection along descending motor pathways (DMPs). We provide an affordable, safe, and timely algorithm for preoperative DTI motor reconstruction for gliomas adjacent to DMPs. Methods: Preoperative DTI reconstructions were extracted from a prospectively acquired registry of glioma resections adjacent to DMPs. The surgeries were performed over a 7-year period. Demographic, clinical, and radiographic data were extracted from patients' electronic medical records. Results: Nineteen patients (12 male) underwent preoperative tractography between January 1, 2013, and May 31, 2020. The average age was 44.5 years (range, 19-81 years). A complete radiological resection was achieved in nine patients, a subtotal resection in five, a partial resection in three, and a biopsy in two. Histopathological diagnoses included 10 patients with high-grade glioma and nine with low-grade glioma. A total of 16 perirolandic locations (10 frontal and six frontoparietal) were recorded, as well as two in the insula and one in the basal ganglia. In 9 patients (47.3%), the lesion was in the dominant hemisphere. The median preoperative and postoperative Karnofsky Performance Scores were 78 and 80, respectively. Motor function was unchanged or improved over time in 15 cases (78.9%). Conclusion: This protocol of DTI reconstruction for glioma removal near the DMP shows good results in low-term neurological functional outcomes.

Surgical corridors to foramen magnum meningiomas: a mini-review.

Gross-total resection of foramen magnum meningiomas remains the gold standard of treatment and should be performed whenever possible. The transcondylar approach (and its variations) represents the most used approach for meningiomas located in the lateral or anterior borders of the foramen magnum. Endoscopic transclivus approaches represent a useful option in selected cases of anterior midline foramen magnum meningiomas, to be performed in centers with advanced experience in endoscopic skull base surgery, with the caveats of increased risk of postoperative cerebrospinal fluid leak. Alternatively, radiosurgery remains an option for well-selected cases, especially for the management of asymptomatic patients with small enlarging tumors. Advances in molecular profiling, as well as genetic analysis, may guide adjuvant treatment.

Current Role of Endoscopic Endonasal Approach for Craniopharyngiomas: A 10-Year Systematic Review and Meta-Analysis Comparison with the Open Transcranial Approach.

In recent years, the endoscopic endonasal approach (EEA) for craniopharyngiomas has proven to be a safe option for extensive tumor resection, with minimal or no manipulation of the optic nerves and excellent visualization of the superior hypophyseal branches when compared to the Transcranial Approach (TCA). However, there is an ongoing debate regarding the criteria for selecting different approaches. To explore the current results of EEA and discuss its role in the management of craniopharyngiomas, we performed MEDLINE, Embase, and LILACS searches from 2012 to 2022. Baseline characteristics, the extent of resection, and clinical outcomes were evaluated. Statistical analysis was performed through an X2 and Fisher exact test, and a comparison between quantitative variables through a Kruskal-Wallis and verified with post hoc Bonferroni. The tumor volume was similar in both groups (EEA 11.92 cm3, -TCA 13.23 cm3). The mean follow-up in months was 39.9 for EEA and 43.94 for TCA, p = 0.76). The EEA group presented a higher visual improvement rate (41.96% vs. 25% for TCA, p < 0.0001, OR 7.7). Permanent DI was less frequent with EEA (29.20% vs. 67.40% for TCA, p < 0.0001, OR 0.2). CSF Leaks occurred more frequently with EEA (9.94% vs. 0.70% for TCA, p < 0.0001, OR 15.8). Recurrence rates were lower in the EEA group (EEA 15.50% vs. for TCA 21.20%, p = 0.04, OR 0.7). Our results demonstrate that, in selected cases, EEA for resection of craniopharyngiomas is associated with better results regarding visual preservation and extent of tumor resection. Postoperative CSF leak rates associated with EEA have improved compared to the historical series. The decision-making process should consider each person's characteristics; however, it is noticeable that recent data regarding EEA justify its widespread application as a first-line approach in centers of excellence for skull base surgery.

[Deep brain stimulation for Parkinson's disease: experience, benefits and limitations in a center in Latin America]. / Estimulación cerebral profunda para enfermedad de Parkinson: experiencia, beneficios y limitaciones en un centro en Latinoamérica.

Background: Parkinson's disease is poorly studied in Colombia. It is pharmacologically managed, but for refractory cases, surgery is a therapeutic option, positively impacting on quality of life. Objective: To determine the impact of deep brain stimulation as management in the control of progression in patients with Parkinson's disease attended our institution between the years 2014 to 2020. Method: Descriptive retrospective study, with patients collected between 2014 and 2020 undergoing deep brain stimulation surgery. The MDS-UPDRS (Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale) was applied in the pre- and postoperative period, and the results were compared. Results: 21 patients were included and the UPDRS was applied, finding a decrease in scores in the postoperative period. One patient had an operative site infection. Conclusions: There was an improvement in the MDS-UPDRS score, with a low rate of complications. The procedure time was prolonged from the preoperative evaluation. Deep brain stimulation is the management of choice for refractory Parkinson's disease. The patients in this series showed improvement in their symptoms. Unfortunately, there are limitations to perform this procedure in Colombia, such as the delay in the authorization of the procedure.

Antecedentes: La enfermedad de Parkinson está poco estudiada en Colombia. Es de manejo farmacológico, pero para casos refractarios la cirugía es una opción terapéutica que impacta positivamente en la calidad de vida. Objetivo: Determinar el impacto de la estimulación cerebral profunda como manejo en el control de la progresión en pacientes con enfermedad de Parkinson atendidos nuestra institución entre los años 2014 a 2020. Método: Estudio descriptivo de corte retrospectivo con pacientes recolectados entre los años 2014 y 2020 sometidos a cirugía de estimulación cerebral profunda. Se aplicó la MDS-UPDRS (Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale) en el pre- y el posoperatorio, y se compararon los resultados. Resultados: Se incluyeron 21 pacientes y se les aplicó la MDS-UPDRS, encontrando una disminución en las puntuaciones en el posoperatorio. Un paciente presentó infección del sitio operatorio. Conclusiones: Hubo mejoría en la puntuación de la MDS-UPDRS, con baja tasa de complicaciones. El tiempo de realización del procedimiento fue prolongado desde la valoración preoperatoria. La estimulación cerebral profunda es el manejo de elección para la enfermedad de Parkinson refractaria. Los pacientes de esta serie mostraron mejoría en sus síntomas. Desafortunadamente, existen limitaciones para la realización de este procedimiento en Colombia, como el retraso en la autorización del procedimiento.

Standardization of Strategies to Perform a Parafascicular Tubular Approach for the Resection of Brain Tumors in Eloquent Areas.

OBJECTIVE: The aim of this work is to define a methodological strategy for the minimally invasive tubular retractor (MITR) parafascicular transulcal approach (PTA) for the management of brain tumors sited in eloquent areas. METHODS: An observational prospective study was designed to evaluate the benefits of PTA associated with MITRs, tractography and intraoperative cortical stimulation. They study was conducted from June 2018 to June 2021. Information regarding white matter tracts was processed, preventing a potential damage during the approach and/or resection. All patients older than 18 years who had a single brain tumor lesion were included in the study. Patients with a preoperative Karnofsky Performance Scale (KPS) score greater than 70% and a Glasgow Coma Scale (GCS) score > 14 points were included. RESULTS: 72 patients were included in the study, the mean age was 49.6, the most affected gender was male, 12.5% presented aphasia, 11.1% presented paraphasia, 41.6% had motor deficit, 9.7% had an affection in the optic pathway, the most frequently affected region was the frontal lobe (26.3%), the most frequent lesions were high-grade gliomas (34.7%) and the measurement of the incisions was on average 5.58 cm. Of the patients, 94.4% underwent a total macroscopic resection and 90.2% did not present new postoperative neurological deficits. In all cases, a PTA was used. CONCLUSION: Tubular minimally invasive approaches (MIAs) allow one to perform maximal safe resection of brain tumors in eloquent areas, through small surgical corridors. Future comparative studies between traditional and minimally invasive techniques are required to further investigate the potential of these surgical nuances.

Micromirrors in Neurosurgery: Technical Overview and Benefits Assessment.

AIM: To weight the benefits and limitations of intraoperative use of micromirrors in neurosurgery. MATERIAL AND METHODS: Surgical cases where micromirrors were employed were retrospectively selected from the surgical database of five different surgeons in different hospitals. Complications directly attributable to the micromirrors were assessed intraoperatively and confirmed with postoperative neuroimaging studies. RESULTS: Fourteen patients were selected. The site of the lesion was as follows: posterior fossa (43%), frontal lobe (22%), temporal lobe (14%), parietal lobe (7%), insula (7%), and basal ganglia (7%). Five tumors (35%) were gliomas, 3 (21%) epidermoid, and 3 (21 %) supratentorial metastases. Two patients underwent microvascular decompression for neurovascular conflict, and 1 harbored a brain arteriovenous malformation. A gross total resection was achieved in all the tumors and the AVM, while an effective decompression was successfully performed in both patients with conflict. No complications directly attributable to the use of the micromirror occurred. A relatively easy learning curve was noted. CONCLUSION: Micromirrors proved to be useful in enhancing the visualization of neurovascular structures and pathology residuals within deep-seated surgical fields without the need for fixed brain retraction. Their cost-effectiveness and easy learning curve constitute solid reasons for advocating a revitalization of this ?old but gold? tool in neurosurgery.

Postnatal Surgical Correction of Myelomeningoceles: Preoperative and Intraoperative Risk Factors Associated with Postoperative Neurologic Outcomes.

OBJECTIVE: Open spina bifida or myelomeningocele (MMC) is a congenital defect that results from failure of caudal neurulation. We present a case series of patients who were treated with postnatal surgical correction for MMC, evaluating the possible preoperative and intraoperative risk factors associated with neurologic outcomes. METHODS: A retrospective chart review of patients who underwent postnatal surgical correction for MMCs over 11 years at our institution was performed. MMCs were classified based on their morphologic configuration into 3 types. Type I includes defects without a sac and there is cerebrospinal fluid (CSF) leak. Type II includes where there is a sac ≤4 cm, with or without CSF leak. Type III includes defects with a sac that are greater than 4 cm. RESULTS: Fifty patients were included. The median age of gestation at surgery was 37.4 weeks. There were 30 females (60%). All mothers received adequate folate supplementation. All patients underwent surgical correction in the first 48 hours. Lower extremity motor function at the last clinical follow-up was normal in 34 patients (68%). CSF leak, infection, and mortality were 8%, 2%, and 0%, respectively. Twenty-one patients (42%) underwent ventriculoperitoneal shunt for hydrocephalus. CONCLUSIONS: Despite there being no statistically significant associations with a timely closure, all cases were treated within the first 48 hours and this could influence the low complication rate. Individuals of Hispanic background who received appropriate folate supplementation still had high rates of MMC and we posit that this may be caused in part by a genetic/molecular predisposition.

Treatment Limitations for Pediatric Diffuse Intrinsic Pontine Gliomas in a Middle-Income Country.

Objectives To evaluate the surgical management outcomes in pediatric patients with diffuse intrinsic pontine gliomas (DIPGs) who underwent intended biopsies and partial resections in a middle-income country, highlighting the barriers and challenges of these procedures for further investigation. Methods A retrospective review of a prospective acquired series of patients who underwent biopsy or resection for DIPG between January 2012 and June 2018 at our institution was performed. Results A total of 43 patients with posterior fossa tumors were identified. From these, seven pediatric DIPG cases were enrolled. Five were males. The median age was 5 years (range: 1-12 years). Only one patient (14.3%) had a ganglioglioma, while the others presented pilocytic and diffuse astrocytomas. Two (28.6%) patients had an intentional biopsy, and the other five (71.4%) had a partial resection. In the three (28.6%) patients who presented with associated hydrocephalus, the endoscopic third ventriculostomy was performed in the same surgical time. The median preoperative Lansky play-performance scale (LPPS) was 80 (range: 60-100), while the median postoperative LPPS was 23 (range: 7-52). Conclusion A decrease in overall survival was noted compared with data reported in other series. Multifactorial barriers were discussed including the social, geographic, and economic features that may influence on final outcomes.

The reverse question mark and L.G. Kempe incisions for decompressive craniectomy: A case series and narrative review of the literature.

Background: Decompressive craniectomy (DC) is a lifesaving procedure, relieving intracranial hypertension. Conventionally, DCs are performed by a reverse question mark (RQM) incision. However, the use of the L. G. Kempe's (LGK) incision has increased in the last decade. We aim to describe the surgical nuances of the LGK and the standard RQM incisions to treat patients with severe traumatic brain injury (TBI), intracranial hemorrhage (ICH), empyema, and malignant ischemic stroke. Furthermore, to describe, surgical limitations, wound healing, and neurological outcomes related to each technique. Methods: To describe a prospective acquired, case series including patients who underwent a DC using either an RQM or an LGK incision in our institution between 2019 and 2020. Results: A total of 27 patients underwent DC. Of those, ten patients were enrolled. The mean age was 42.1 years (26-71), and 60% were male. Five patients underwent DC using a large RQM incision; three had severe TBI, one ICH, and one ischemic stroke. The other five patients underwent DC using an LGK incision (one ICH, one subdural empyema, and one ischemic stroke). About 50% of patients presented severe headaches associated with vomiting, and six presented altered mental status (drowsy or stuporous). Motor deficits were present in four cases. In patients with ischemic or hemorrhagic stroke, symptoms were directly related to the stroke location. Hospital stays varied between 13 and 22 days. No readmissions were recorded, and no fatal outcome was documented during the follow-up. Conclusion: The utility of the LGK incision is comparable with the classic RQM incision to treat acute brain injuries, where an urgent decompression must be performed. Some of these cases include malignant ischemic strokes, ICH, and empyema. No differences were observed between both techniques in terms of prevention of scalp necrosis and general cosmetic outcomes.

Resección Tubular Microquirúrgica de un Subependimoma Extenso del Ventrículo Lateral Izquierdo: Video Operatorio en 2D / Microsurgical Tubular Resection of an Extensive Subependymoma of the Left Lateral Ventricle: Operative Video in 2D

Introducción: Los subependimomas intracraneales son raros, representan el 0.2-0.7% de todos los tumores del sistema nervioso central1,2 y se originan en los ventrículos laterales en el 30-40% de los casos.3 Los síntomas usualmente se asocian a hipertensión endocraneana secundaria a hidrocefalia obstructiva.4 La resección completa del tumor es curativa en esta patología.5 El abordaje trans-surcal es seguro para lesiones ventriculares profundas y el uso de los retractores tubulares minimizan la retracción del parénquima cerebral evitando la compresión directa con valvas. Esto permite disminuir la presión del tejido cerebral que puede ocluir los vasos y producir isquemia local generando una lesión neurológica permanente. Descripción del caso: Se presenta el caso de una paciente de 66 años, diestra, con cefalea crónica que aumenta en frecuencia en el último mes. La resonancia cerebral contrastada muestra un tumor extenso en el ventrículo lateral izquierdo con signos de hidrocefalia obstructiva. Intervención: Se coloca la paciente en posición supina. Se hace una incisión bicoronal y se hace un abordaje trans-surcal F1/F2 izquierdo. Se coloca un retractor tubular guiado con el puntero de neuronavegación, introduciéndolo directamente en el parénquima cerebral y fijándolo al soporte de Leyla. Se colocó un catéter de ventriculostomía contralateral y se retira a las 48 horas sin complicaciones asociadas. La resonancia contrastada postoperatoria demuestra una resección completa del tumor. El análisis de patología reveló un subependimoma grado I de la clasificación de la Organización Mundial de la Salud. La paciente presentó transitoriamente apatía y pérdida del control del esfínter urinario que resolvieron completamente a las 3 semanas después de la cirugía. Se firmó un consentimiento firmado para la publicación de la información utilizada en este trabajo. Conclusión: La resección completa microscópica de un subependimoma extenso del ventrículo lateral izquierdo es factible a través de un abordaje tubular transulcal.

Introduction: Intracranial subependymomas are rare, representing only 0.2-0.7% of all central nervous system tumors1,2 and arise in the lateral ventricles in 30-40% of the cases.3 Symptoms depend on tumor location and usually arise when the cerebrospinal fluid (CSF) is blocked, generating a consequent intracranial hypertension.4 Microsurgical gross-total resection is possible and curative for these tumors.5 The transcortical/trans-sulcal approach is a safe approach for the access of deep-seated intraventricular lesions. The use of tubular retractor systems minimizes retraction injury when passing through the cortex and deep white matter tracts. This allows a decrease in the pressure on brain tissue that can occlude the brain vessels and produce local ischemia and a consequent permanent neurological injury. Case description: This is a case of a 66-year-old woman who presented chronic headaches that increased in frequency in the last month. Enhanced-brain MRI demonstrated a large left ventricular lesion with signs of obstructive hydrocephalus. Procedure: Patient was positioned supine. A bicoronal incision was used to perform a left frontal craniotomy. An F1/F2 transcortical/trans-sulcal approach was used. A guided tubular retractor is placed with the neuronavigation pointer, inserting it directly into the brain parenchyma and fixing it to the Leyla support. Postoperative postcontrast MRI demonstrated a complete resection of the tumor. Histopathological analysis revealed a subependymoma (World Health Organization Grade I). The patient presented transient apathy and loss of urinary sphincter control that completely resolved 3 weeks after surgery. Written informed consent was obtained for publication of information used for this work. Conclusions: A complete microsurgical resection of a large left ventricular subependymoma is feasible through a trans-sulcal tubular approach.

Desarrollo de una máscara de bajo costo para prevenir la propagación de aerosoles en endoscopia endonasal en la base del cráneo durante la pandemia del COVID-19 / Development of a low-price mask to prevent spread of aerosols during endoscopic endonasal spread of aerosols during endoscopic endonasal skull base surgery in the COVID-19 pandemicskull base surgery in the COVID-19 pandemicArtículo de investigación ISSN: 0121-7372 • ISSN electrónico: 2462-991X

Objetivo: desarrollar una máscara que sea reutilizable, esterilizable, fácil de usar y económica para reducir los riesgos de transmisión del COVID-19 durante los procedimientos endoscópicos endonasales. Métodos: modelo diseñado en Autodesk Fusion 360 y Meshmixer, construido con ácido poliláctico (PLA) utilizando una impresora 3D (PRUSA IK3 MK3s, Praga, República Checa) en el laboratorio de Anatomía de la Universidad de los Andes, Bogotá, Colombia. Se ajustaron tres orificios a la mascarilla, uno para el tubo endotraqueal, otro más grande en el medio para la instrumentación quirúrgica que permite la adaptación de una membrana translúcida estéril y el superior para adaptar la punta de la succión y generar un ambiente de presión negativa dentro de la máscara. Se utilizó un colchón de silicona y tres puntos para sujetar tiras y crear un ajuste a la cabeza durante largos períodos sin causar lesiones en la piel. Se realizaron diferentes pruebas, incluida la verificación con luz ultravioleta de la propagación de la fluoresceína después de la perforación ósea, la esterilización química y por calor de la máscara, y la succión de los aerosoles producidos al fumar un cigarrillo electrónico. Ambiente: laboratorio experimental. Resultados: las pruebas demostraron una reducción del efecto aerosol y de la dispersión de las gotas cuando se usa la máscara ventilada. Se consiguió una excelente maniobrabilidad y libertad. Sin embargo, fue limitado en términos de visualización durante la entrada nasal de los instrumentos al cráneo. Conclusiones: los resultados preliminares muestran que esta máscara ventilada permite una barrera quirúrgica para disminuir la transmisión del SARS-COV-2 durante los procedimientos endoscópicos endonasales.

Objective: to develop a reusable, sterilizable, easy- to-use and low-price mask to reduce the risks of COVID-19 transmission during endonasal endoscopic procedures. Methods: a model designed using Autodesk Fusion 360 and Meshier software, made from polylactic acid (PLA) in a 3D printer (PRUSA IK3 MK3s, Prague, Czech Republic) at the anatomy laboratory of Universidad de los Andes, Bogotá, Colombia. It features three ports, one to allow passage of intubation tubing, a larger middle port for surgical tool insertion, which allows fitting a sterile translucent membrane, and an upper port for the suction tube tip to create a negative pressure environment inside the mask. A silicone cushion and three ties secure the mask to the head for long periods of time without skin injuries. Various tests were completed, ultraviolet light verification of fluorescein propagation after bone drilling, chemical and vapor sterilization, and aerosols filtration using smoke produced by an electronic cigarette. Setting: an experimental laboratory. Results: Tests showed the mask decreased aerosol effect and droplet dispersion, and allowed for excellent maneuverability and freedom. However, the mask was limited in terms of visualization during nasal approaches to the skull. Conclusions: preliminary results show that this ventilated mask allows for a surgical barrier for reducing SARS-COV-2 transmission during endonasal endoscopic procedures.

Lista de chequeo preoperatorio para la cirugía endoscópica de hipófisis / Preoperative checklist for endoscopic pituitary surgery

Introducción: las listas de chequeo son herramientas que buscan evitar errores y complicaciones al momento de realizar un procedimiento. El adenoma hipofisiario es la primera causa de cirugía endoscópica transnasal de la región selar, y se estima que ocurren hasta un 20 % de complicaciones derivadas de esta cirugía. Objetivo: desarrollar una lista de chequeo preoperatoria que sirva como una guía para la evaluación prequirúrgica de los pacientes a quienes se les realicen cirugías de la región selar. Metodología: se realizó una revisión de la literatura para desarrollar una lista de chequeo preliminar y una serie de declaraciones que resumían los puntos importantes de la lista. Se construyó un comité de expertos en cirugía endoscópica de la base de cráneo conformado por neurocirujanos y otorrinolaringólogos de hospitales de Bogotá. Utilizando la metodología Delphi modificada, se llegó a un consenso para la realización de la lista de chequeo final. Resultados: se describieron 15 declaraciones; de estas, hubo una discrepancia en 6 declaraciones. Por esta razón, se realizaron modificaciones en 5 declaraciones, y se llegó a un consenso entre los expertos participantes. La lista de chequeo final aprobada está compuesta por 4 ítems. Discusión/conclusiones: la cirugía para el manejo de la patología de la región selar es compleja y requiere de un equipo quirúrgico entrenado y disciplinado para lograr los mejores desenlaces posibles. Consideramos que nuestra lista de chequeo es una herramienta que permitirá a los equipos que realizan estas cirugías en Colombia tener una visión más completa del paciente y, eventualmente, ayudar a evitar errores y posibles complicaciones.

Introduction: checklists that seek to avoid errors are very useful tools for any surgical practice. Pituitary adenomas are the leading indication to perform a transnasal endoscopic surgery in the sellar region and up to 20 % complications have been reported related to this procedure. Objetive: develop a preoperative checklist, based on an expert consensus, to serve as a guide for the skull base teams to consistently evaluate preoperatively all patients with pathologies in the sellar region. Methods: a literature review was conducted to develop a preliminary checklist and a series of statements summarizing the most important items on the list. A committee of experts in endoscopic skull base surgery was summoned, made up of neurosurgeons and otolaryngologists from hospitals in Bogotá. Using the modified Delphi methodology, a consensus was reached for the completion of the final checklist. Results: fifteen statements were developed. A discrepancy was seen in six statements. Modifications were made for five statements, thus reaching a consensus among the participating experts. The final approved checklist is made up of 4 items. Conclusion: surgery for treating different pathologies in the sellar region is complex and requires a welltrained and disciplined surgical team to achieve the best possible outcomes. We consider that our preoperative checklist is a valuable resource for skull base surgical teams performing transnasal endoscopic surgery of the sellar region. This tool will allow skull base surgical teams in Colombia to have a more comprehensive view of the patient and eventually help to avoid errors and possible complications.