Three-Stage Surgical Resection in Semisitting Position of Sphenocavernopetroclival-Foramen Magnum Meningioma: 3-Dimensional Operative Video.

Large meningiomas extending through the middle cranial fossa, posterior fossa, and foramen magnum (FM) represent a surgical challenge even for experienced skull base surgeons.1 Although decompression may be necessary for offering clinical improvement, surgical risks may involve cranial nerves and vascular injury. We present a case of a sphenocavernopetroclival-FM meningioma, with our surgical plan extending through the sphenoid region, FM, and posterior fossa to the anterior arch of C1. We designed a 2-day, 3-stage surgical strategy to achieve complete surgical resection for offering better long-term prognosis and satisfactory postoperative neurological outcome.2 The surgical plan was completed in 2 days of surgery: the first day the extradural part for achieving optimal tumor exposure and the second day the intradural part to tackle tumor resection in a 3-stage fashion. The first stage consisted in a far lateral approach to access the lower portion of the tumor extending from the FM to the spinal region; the second stage focused on the portion of the tumor extending through the inferior clivus and the petroclival region; and the third stage consisted in resecting the tumor extending from the petroclival region to the sphenoid region.3 A near-total resection was achieved, with a very small tumor remnant observed at the level of the tentorium on postoperative MRI, which was treated with radiosurgery owing to the young age of the patient. This is a 3-dimensional operative video showing the surgical steps of the tumor resection. The patient consented to the procedure and to the publication of her image.

Endoscopic Ventricular Lavage in Pediatric Pyogenic Cerebral Ventriculitis Associated with Shunt: Outcomes and Technical Notes.

OBJECTIVE: Pyogenic cerebral ventriculitis (PCV) is a rare infectious entity characterized by a potent inflammatory reaction of the ventricular ependyma, which in most cases leads to death. We aim to present the technical note and protocol, based on our center's 10-year experience of the use of endoscopic ventricular lavage (EVL) in pediatric patients with PCV and ventricular peritoneal shunt. METHODS: For this study, all pediatric patients (<16 years) with VP shunts and PCV who were treated with EVL between January 2012 and January 2022 were included. RESULTS: Thirty-four pediatric patients with ventriculitis were analyzed. The median age was 6 years, with 61.7% being male. Most consultations occurred on Day 2 of symptoms. Fever (38.2%) and altered consciousness (26.5%) were the most common initial symptoms. Early ventriculitis was observed in 67.7% of patients. Pathogen identification in the initial cerebrospinal fluid sample was 70.6%, while samples from ventricular peritoneal shunt yielded 23.53% and catheter culture 79.4%. Gram-positive bacteria, mainly S.epidermidis (44.1%), was the most commonly isolated agent. EVL was performed in 73.5% on the second or third day. Reinfection occurred in 23.5%, and 26.5% of patients died. Concordance analysis showed 85.3% agreement between LP and catheter tip samples. Functionality improved, with 55.88% achieving a Lansky score of 90. Early ventriculitis was associated with better Lansky scores. CONCLUSION: EVL can be a useful tool in the management of PCV in cases with VP shunts. Our study suggests a higher chance of isolating an infection-causing germ in the catheter tip culture specimen compared to the cerebrospinal fluid culture. However, future studies with a larger number of patients, or multicentric studies are required for further analysis.

The M-Point A Novel Landmark in Middle Fossa Surgery: A Cadaveric Morphometric Study.

BACKGROUND: The arcuate eminence (AE) is an anatomically consistent bony protrusion located on the upper surface of the petrous bone that has been previously studied as a reference for lateral skull base approaches. There is a paucity of information in the neurosurgical literature seeking to improve the safety of the extended middle cranial fossa (MCF) approach using detailed morphometric analysis of the AE. OBJECTIVE: To evaluate the use of the AE as an anatomical landmark to help with early identification of the internal acoustic canal (IAC) in MCF approaches by means of a cadaveric study, using a new morphometric reference termed the "M-point." METHODS: A total of 40 dry temporal bones and 2 formalin-preserved, latex-injected cadaveric heads were used. The M-point was established as a new anatomic reference by identifying the intersection of a line perpendicular to the alignment of the petrous ridge (PR), originating from the midpoint of the AE, with the PR itself. Subsequent anatomical measurements were performed to measure the distance between M-point and IAC. Additional distances, including PR length and the anteroposterior and lateral AE surfaces, were also measured. RESULTS: The mean distance between the M-point and the center of the IAC was 14.9 mm (SD ± 2.09), offering a safe drilling area during an MCF approach. CONCLUSIONS: This study provides novel information on identification of a new anatomic reference point known as the M-point that that can be used to improve early surgical identification of the IAC.

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.

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.

Anatomic variations of the floor of the third ventricle: Surgical implications for endoscopic third ventriculostomy.

Background: Endoscopic third ventriculostomy (ETV) is currently used as a treatment for different types of hydrocephalus. However, the anatomical endoscopic variants of the third ventricle floor (3VF), as well as their surgical implications, have been underrated. The anatomic variations of the 3VF can influence the technique and the success rate of the ETV. The purpose of this article is to describe the anatomical variations of 3VF, assess their incidence, and discuss the implications for ETV. Methods: Intraoperative videos of 216 patients who underwent ETV between January 2012 and February 2020 at Hospital Infantil Universitario de San José, Bogotá, Colombia were reviewed. One hundred and eighty patients who met the criteria to demonstrate the type of 3VF were selected. Results: 3VF types were classified as follows: (1) Thinned, (2) thickened, (3) partially erased, (4) globular or herniated, and (5) narrowed. Conclusion: Knowledge of anatomical variations of the 3VF is paramount for ETV and it influences the success rate of the procedure.

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.