Surgical Anatomy and Technique of Peri-Insular Hemispherotomy in Pediatric Epilepsy.

BACKGROUND AND OBJECTIVES: Hemispherotomy is a highly complex procedure that demands a steep learning curve. An incomplete brain disconnection often results in failure of seizure control. The purpose of this article was to present a step-by-step guide to the surgical anatomy of this procedure. It is composed of a 7-stage approach, enhancing access to and improving visualization of deep structures. METHODS: A retrospective analysis of 39 pediatric patients with refractory epilepsy who underwent this technique was conducted. Engel scores were assessed 1 year postsurgery. Cadaveric dissections were performed to illustrate the procedure. RESULTS: Between 2015 and 2022, 39 patients were surgically treated using the peri-insular technique. The technique involved 7 stages: patient positioning, operative approach, opercular resection, transventricular callosotomy, fronto-orbital disconnection, anterior temporal disconnection, and posterior temporal disconnection. Most of the patients (92.30%) were seizure-free (Engel class I) at 1 year postoperative, 5.13% were nearly seizure-free (Engel II), and 2.56% showed significant improvement (Engel III). Complications occurred in 8% of cases, including 1 infection, 2 cases of aseptic meningitis, and 1 non-shunt-requiring acute hydrocephalus. CONCLUSION: The peri-insular hemispherotomy technique offers excellent seizure control with a low complication rate. Our visual documentation of surgical anatomy, complemented by detailed descriptions of surgical nuances, significantly contributes to a comprehensive understanding of this technique.

Neurosurgical simulation models developed in Latin America and the Caribbean: a scoping review.

Simulation training is an educational tool that provides technical and cognitive proficiency in a risk-free environment. Several models have recently been presented in Latin America and the Caribbean (LAC). However, many of them were presented in non-indexed literature and not included in international reviews. This scoping review aims to describe the simulation models developed in LAC for neurosurgery training. Specifically, it focuses on assessing the models developed in LAC, the simulated neurosurgical procedures, the model's manufacturing costs, and the translational outcomes. Simulation models developed in LAC were considered, with no language or time restriction. Cadaveric, ex vivo, animal, synthetic, and virtual/augmented reality models were included for cranial and spinal procedures. We conducted a review according to the PRISMA-ScR, including international and regional reports from indexed and non-indexed literature. Two independent reviewers screened articles. Conflicts were resolved by a third reviewer using Covidence software. We collected data regarding the country of origin, recreated procedure, type of model, model validity, and manufacturing costs. Upon screening 917 studies, 69 models were developed in LAC. Most of them were developed in Brazil (49.28%). The most common procedures were related to general neurosurgery (20.29%), spine (17.39%), and ventricular neuroendoscopy and cerebrovascular (15.94% both). Synthetic models were the most frequent ones (38.98%). The manufacturing cost ranged from 4.00 to 2005.00 US Dollars. To our knowledge, this is the first scoping review about simulation models in LAC, setting the basis for future research studies. It depicts an increasing number of simulation models in the region, allowing a wide range of neurosurgical training in a resource-limited setting.

Results of training with a low-cost simulation model for endoscope-assisted scaphocephaly repair.

OBJECTIVE: Endoscope-assisted repair of sagittal craniosynostosis is an effective technique that requires a learning curve. Surgical simulation models can be applied to acquire the necessary skills for this procedure. Several models with a wide range of costs have been described for training in this technique. The aim of this work was to present the results of training with a low-cost simulation model for endoscope-assisted sagittal craniosynostosis repair. METHODS: A simulation model for sagittal craniosynostosis was developed using low-cost materials. The model is easily assembled and allows successive uses. Three neurosurgery residents, 3 fellows, and 2 neurosurgeons performed a 4-session training program in sagittal craniosynostosis repair. The Global Rating Scale (GRS) score, number of errors, and the time required to perform the task were reported by 2 independent evaluators using a checklist. Measurements were compared between the first and last training using the Wilcoxon signed-rank test. All participants completed a questionnaire (5-point Likert scale) regarding the realism of the simulation model. RESULTS: A model was developed to recreate the steps required to perform an endoscope-assisted scaphocephaly repair with the patient in a simulated sphinx position. All participants improved their GRS performance between the first and final training. The median time needed to perform the initial training was 47.5 minutes (interquartile range [IQR] 44.5-48 minutes, interrater difference [IRD] p = 0.77), and for the last training was 40.5 minutes (IQR 35.5-43 minutes, IRD p > 0.99). The median number of errors reported in the initial training was 5.5 (IQR 3-7.75 errors, IRD p = 0.8), and in the last training was 1 (IQR 0.75-2.25 errors, IRD p = 0.35). There was a statistically significant difference regarding the time and number of errors between the initial and final training (p < 0.001). More than 85% of the participants found that the surface anatomy, skull and anterior fontanel, fused sagittal suture, and epidural space of the model were realistic and had appropriate detail required to perform the surgery. All respondents agreed or strongly agreed that the endoscope handling was realistic, and that the steps and skills required to complete the task were representative of those required for the real procedure. CONCLUSIONS: A low-cost sagittal craniosynostosis simulation model was developed, allowing successive uses. The acquisition of skills within the simulation was demonstrated for all participants regarding the GRS score and the number of errors and time needed to perform the task. In addition, the model was found to be realistic in terms of anatomical references and the procedural steps required for this minimally invasive technique.

Case report: double dermal sinus tracts of the cervical and thoracic spine associated with congenital intracranial pathology (hydrocephalus and an interhemispheric cyst) in a newborn patient.

INTRODUCTION: A dermal sinus tract (DST) is an uncommon type of spinal dysraphisms characterized by a tract lined with stratified squamous epithelium that extends from the subcutaneous tissue to the underlying thecal sac or neural tube. These developmental anomalies can present asymptomatically with cutaneous abnormalities or with devastating complications. Usually, it is presented as a unique lesion, and there are only a few reports that show multiple sinuses, and none of them associated with midline brain malformations. METHODS: We present the case of a 3-day-old girl with an antenatal diagnosis of hydrocephalus who was diagnosed with double dermal sinus tracts of the cervical and thoracic regions at admission. The patient presented signs of elevated intracranial pressure (ICP), which imposed a challenge in the management of the case. RESULTS: Our patient was successfully treated initially with a lumbar puncture in order to discard a cerebrospinal fluid (CSF) infection. With negative CSF cultures, a ventriculoperitoneal shunt (VPS) was placed. Nine days after the VPS surgery and without signs of infection, the DST was excised in a single procedure, without follow-up complications. CONCLUSION: To our knowledge, this is the first description of a patient with multiple midline neural tube defects (NTDs) associated with congenital intracranial pathology. Although there are no guidelines regarding the best treatment for this complex associated pathology, the patient was treated, without follow-up complications.

Abusive head trauma, protocols, and legal concerns in a South American Country.

The abusive head trauma (AHT) is a form of child abuse and is a frequent entity all over de world. It is particularly unique among medical diagnoses because of the legal implications imposed by the diagnosis. Therefore, it has been the subject of much legal controversy over the decades. Knowledge of the clinical signs and imaging findings of abusive head trauma is vitally important for early diagnosis. An oriented anamnesis, as well as a complete physical examination and obtaining adequate images of the central nervous system, play a significant role in confirming the presumptive diagnosis. The interdisciplinary approach (pediatricians, neurosurgeons, neuroradiologists, social workers, and other specialists) is the key in the management of these patients. The purpose of this article is to familiarize the pediatric neurosurgeon with some of the more common medicolegal issues surrounding AHT as well as to discuss legal commitments and ethical obligations of the neurosurgeon in Argentina (South America) based on 2 clinical cases.

A Low-Cost Simulation Model for Endoscopic-Assisted Sagittal Craniosynostosis Repair.

OBJECTIVE: The objective is to introduce a low-cost simulation model for endoscopic-assisted sagittal craniosynostosis repair in which bleedings can be simulated and to present the initial experience using the model as a learning tool. METHODS: A 3-dimensional synthetic skull was printed using polylactic acid. The brain, dura mater, sagittal sinus, and skin were constructed using low-cost materials. The simulation was performed at Garrahan Pediatric Hospital's simulation center employing a rigid endoscope (Pes Pilot HD 0° 4 mm). RESULTS: A low-cost simulation model for sagittal craniosynostosis was built in order to recreate the steps needed to perform a strip craniectomy with lateral extensions. The initial estimated cost is 10 U.S. dollars, and subsequent uses cost approximately 2 U.S. dollars. Four training sessions were performed, and a reduction in surgical time was recorded from 125 to 80 minutes. CONCLUSIONS: We introduce a low-cost simulation model for scaphocephaly endoscopic-assisted surgery in which bleeding can be reproduced. The initial experience shows the possibility of using the model as a learning tool.

Choroid plexus cyst causing acute hydrocephalus and transtentorial herniation: report of a rare case and its successful neuroendoscopic treatment.

Choroid plexus cysts (CPC) are a frequent incidental neuroimaging finding and completely asymptomatic in the vast majority of cases. We hereby describe a rare case of acute hydrocephalus secondary to a CPC, atypical in size, location and presentation, which required urgent neuroendoscopic management. There are very few reported cases of CPC causing obstructive hydrocephalus. The authors present the case of a previously healthy 2-year-old boy with severe symptoms of acute intracranial hypertension, triventricular hydrocephalus, and left ventricle exclusion after placement of a right external ventricular drain. Magnetic resonance imaging (MRI) showed a very subtle gadolinium enhancement in the anterior region of the third ventricle and foramen of Monro (FM). An emergency neuroendoscopic exploration was performed, where a big cyst was found in the choroid plexus near the FM. The foramen was completely unblocked by thoroughly fenestrating and coagulating the cyst, and a preventive endoscopic septum pellucidotomy was done in the same procedure. The patient completely resolved his symptoms, without neurological morbidity or requirement of a cerebrospinal fluid shunt placement. It is important to consider this infrequent presentation in cases of acute or intermittent obstructive hydrocephalus without apparent cause, bearing in mind its difficult detection in neuroimaging studies and the possibility of effective neuroendoscopic treatment.

Sagitectomía Endoscópica: Planeamiento Quirúrgico con Modelos de Simulación de Bajo Costo / Endoscopic Sagitectomy: Surgical Planning with Low-Cost Simulation Models

Objetivos: El objetivo es presentar un caso de sagitectomía asistida por endoscopía y su planificación y entrenamiento prequirúrgico con modelos de simulación de bajo costo. Métodos: Se procesó una tomografía de un paciente con escafocefalia, a partir de la cual se realizó una impresión 3D de un cráneo sin huesos parietales. Se completó el modelo de simulación con materiales de bajo costo para simular los tejidos blandos y hueso. Se realizó el entrenamiento con un endoscopio de 30º. Luego del entrenamiento, se realizó una cirugía en un paciente de 2 meses de edad que presentaba una escafocefalia. Resultados: Se creó un modelo de simulación de bajo costo (aproximadamente 20 US$) para el entrenamiento de sagitectomía asistida por endoscopía. Se realizó la cirugía en un paciente, sin complicaciones quirúrgicas ni posoperatorias. Conclusión: El entrenamiento con simuladores de bajo costo permite planificar una sagitectomía asistida por endoscopía, disminuyendo los errores y los tiempos de la curva de aprendizaje.

Nuevos paradigmas en el diagnóstico y tratamiento de los tumores neuroepiteliales disembrioplásticos (DNT) / New paradigms in the diagnosis and treatment of dysembryoplastic neuroepithelial tumors (DNT)

Introducción: Los tumores neuroepiteliales disembrioplásticos (DNT) han sido considerados lesiones benignas y estables, sin embargo existen casos que han presentado evoluciones inusuales a lo largo de su seguimiento. Objetivo: Analizar las características clínicas, imagenológicas, quirúrgicas y hallazgos anatomopatológicos de un grupo de pacientes con diagnóstico original de DNT e identificar características que puedan prever una evolución atípica de los mismos. Métodos: Se analizaron retrospectivamente historias clínicas de 65 pacientes con diagnóstico confirmado de DNT desde 1985 a 2016. Se evaluó clínica, imágenes, cirugía, anatomía patológica y evolución a largo plazo haciendo hincapié en la recidiva tumoral y sus relaciones con los hallazgos de imágenes y clínica. Para el análisis estadístico se utilizó el Test X2 y en las muestras donde el valor esperado era menor a 5 se usó el Test de Fisher. Para comparar medias se utilizó el t-test. Resultados: La distribución etaria mostró un leve predominio masculino 1; 1,7, con una edad promedio de presentación de síntomas de 6,6 años, con una edad promedio a la cirugía de 9,7 años. La localización más frecuente fue el lóbulo frontal con el 45%, seguido por el lóbulo temporal con el 38% de los casos. Se realizó exéresis total solo en el 42% (27/65) de los pacientes. La patología mostró patrones típicos de DNT en el 90% de los casos. Las imágenes prequirúrgicas mostraron patrones típicos en un 65% (42/65) de los pacientes y atípicos en un 35% (23/65). El 46% (30/65) de los pacientes presentaron recidiva tumoral a lo largo del seguimiento. El tiempo promedio de la aparición de la recidiva fue de 4.5 años (6 meses a 13 años ). Los pacientes que recidivaron todos habían tenido exéresis parciales (30/30), entre los que no recidivaron el 77% (27/35) tenía exéresis completa y 23% (8/35) exéresis parcial. El síntoma más frecuente en las recidivas fue la aparición de crisis convulsivas en un 77%. El tiempo de seguimiento promedio fue de 9,2 años (±6,9 DS), el 85% de los pacientes están sin crisis convulsivas y el 55% (36/65) de estos están sin medicación. Conclusión: A pesar del comportamiento benigno en la mayoría de los DNT existen pacientes que pueden presentar recidiva. Estas recidivas no necesariamente implican transformación maligna a pesar de los cambios en las imágenes y la patología que pueden encontrarse. La exéresis completa de la lesión en la primera cirugía ha demostrado ser el factor pronóstico más importante. El seguimiento debe ser estricto, ya que se han visto recidivas posteriores a periodos libres de enfermedad prolongados. Es muy importante realizar un exhaustivo análisis de las imágenes pre y post quirúrgica para poder identificar características que nos permitan predecir comportamientos inusuales.

Introduction: Neuroepithelial dysembrioplastic tumors (DNT) have long been considered benign, stable lesions. However, some patients have unusual presentations and disease course. Objectives: To analyze clinical, imaging, surgical and anatomopathological findings in a cohort of patients with an original diagnosis of DNT, and identify characteristics that may predict an atypical disease course. Methods: We retrospectively analyzed the clinical records of 65 patients with a diagnosis of DNT confirmed from 1985 to 2017. Relationships between long-term disease evolution, emphasizing tumor recurrence, and baseline clinical, imaging, surgical and histopathological findings were assessed. For inter-group comparisons between patients with versus without tumor recurrence, categorical variables were analyzed using Pearson χ2 analysis or Fisher's Exact Test, as appropriate, while continuous variable means were compared via unpaired Student's t-tests. Results: Males out-numbered females by a ratio of 1.7 to 1. The average age at presentation with symptoms was 6.6 years, with an average age at surgery of 9.7 years. The frontal and temporal lobes were the most frequent tumor locations, accounting for 45 and 38% of cases, respectively. Gross total resection was achieved in 42% (27/65) of patients. Pathology was typical of DNT in 90% of cases, while pre-surgical images exhibited typical findings in 65%, atypical in 35%. Thirty patients (46%) experienced tumor recurrence over the course of follow-up. The average time to recurrence was 4.5 years (6 months to 13 years). All patients who relapsed had initially undergone partial excision (30/30). Among those whose tumor did not recur, 23% (8/35) had undergone partial excision. The most frequent presenting symptom with recurrences was seizures, which occurred in 77%. Overall follow-up of patients has been 9.2 years (±6.9 SD), amongst whom 85% are currently seizure-free, and 55% require no seizure medication Conclusions: Despite the benign behavior of most DNT, almost half of patients experience tumor recurrence. These recurrences do not necessarily involve malignant transformation, despite imaging and pathology changes that may be encountered. Extent of tumor resection (gross vs. partial) is the strongest predictor of tumor recurrence. Vigilant long-term monitoring is indicated, because recurrences may occur after prolonged disease-free periods.

Fistulas piales cerebrales en pediatría / Pial shunts in pediatric patients

Objective: to analyze our experience in brain pial arteriovenous fistulae in paediatric patients and review the modern concepts about this pathology.Materials and method: between 2004 and 2011, 6 cases of pial arteriovenous fistulae were diagnosed and treated at the National Hospital of paediatrics “Juan P.Garrahan”, defining them as arteriovenous malformations with one or more arterial connections with one single venous drainage, without interposed nidus. We reviewed the medical records and neuroimaging. The main method for diagnosis was cerebral angiography. Results: there were 4 male and 2 female patients, ages ranging from 1 month to 14 years old. 3patients presented brain hemorrhage, 2 had seizures as the initial symptom, and one was diagnosed because of his congenital hydrocephalus. 2 were treated with open surgery and 4 with embolisation. There were no important complications or rebleeding. Conclusion: brain pial fistulas are infrequent vascular malformations important for their high risk of bleeding and relative frequency in paediatrics. The management of these patients needs a multidisciplinary team for analysis, discussion, choosing the most suitable treatment, and follow up.