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.

Microsurgical Resection of a Medulla Oblongata Cavernoma: 3-Dimensional Operative Video.

Cavernous malformations occur in approximately 0.5% of the population. When it comes to the medulla oblongata, the incidence rate is around 5%.1,2 Patients with these conditions face potential risks such as hemorrhaging, substantial mortality, and morbidity. The symptoms experienced by the patient vary depending on the extent of hemorrhaging and the location of the lesion. Surgery stands as the primary and essential form of treatment in these cases.1-4 The aim of this operative video was to present the removal of a medulla oblongata cavernoma. The patient consented to the procedure and to the publication of her images and surgical video. We describe the case of a 53-year-old woman presenting with headaches and with swallowing difficulties, being tracheostomized on hospital admission. Magnetic resonance imaging showed a lesion located at the medulla oblongata. Owing to the patient's symptoms and cavernoma bleeding, surgical resection was determined. There were no adverse outcomes after surgery, and the patient evolved favorably. Postoperative imaging displayed complete removal of the cavernoma. Microsurgical resection of cavernomas in this location with neurophysiological monitoring and selection of the safe entry zone is an effective option.1-4.

[Neurovascular decompression in trigeminal neuralgia: Functional outcome]. / Descompresión neurovascular en neuralgia trigeminal: resultado funcional.

INTRODUCTION: The most frequent pathology of the fifth cranial nerve is trigeminal neuralgia (TN), characterized by unilateral orofacial pain, of a paroxysmal nature, with distribution in one or more divisions of the trigeminal nerve. The main objective of this work is to demonstrate the efficacy and safety of neurovascular decompressive surgery (NVD). METHODS: Retrospective analytical study, patients operated on for NVD by TN (n: 155), from January 2006 - 2022, using a retrosigmoid approach and clinicalradiological follow-up, whose intraoperative recording was in 3D system (n: 42). RESULTS: 83.3% (n=35) presented classic NT and 16.7% (n = 7) idiopathic. The right side prevailed with 59.5% (n = 25) and paroxysmal pain with 81% (n=34) of representation in the entire series. Compression of arterial origin represented 76.2% (n: 32) of the cases, the superior cerebellar artery represented the first cause of neurovascular compression (NVC) in 52.4% (n: 22) in the exit zone of the trigeminal nerve. The validity of the magnetic resonance imaging (MRI) protocol selected for this series was analyzed; evidencing a high sensitivity of MRI with 97%, and a specificity of 86%. CONCLUSION: The sensitivity and specificity of highdefinition MRI studies and with special protocols for the evaluation of TN, as gold standard paraclinical, were presented. The DNV offered safe results, a high percentage of the patients were described as successful. The 3D recording allowed retrospective analysis with a vision identical to that of the surgeon during the intraoperative period, the type of NVC.

Introducción: La afección más frecuente del V nervio craneal es la neuralgia del trigémino (NT), se caracteriza por dolor orofacial unilateral, paroxístico, distribuyéndose en una o más divisiones del nervio trigémino. El objetivo de presente trabajo es demostrar la eficacia y seguridad de la cirugía descompresiva neurovascular (DNV). Métodos: Estudio analítico retrospectivo, pacientes intervenidos para DNV por NT (n: 155), desde enero de 2006 - 2022, mediante un abordaje retrosigmoideo y seguimiento clínico-radiológico, cuyo registro intraoperatorio fue en sistema 3D (n: 42). Resultados: 83.3% (n=35) presentó NT clásica y 16.7% (n = 7) idiopática. La mayoría con afectación del lado derecho 59.5% (n = 25) y el dolor paroxístico con 81% (n = 34). La compresión de origen arterial representó 76.2% (n: 32) de los casos, la arteria cerebelosa superior representó la primera causa de compresión neurovascular (CNV) en un 52.4% (n:22) en la zona de salida del nervio trigémino. Se analizó la validez del protocolo de resonancia magnética (RM) seleccionado para esta serie; evidenciando una alta sensibilidad de la RM con 97%, y una especificidad del 86%. Conclusión: Se demostró la sensibilidad y especificidad de los estudios de resonancia magnética (RM) de alta definición y con protocolos especiales para la evaluación de la NT, como paraclínico estándar de oro. La DNV ofreció resultados seguros, un alto porcentaje de los pacientes se calificaron como exitosos. El registro 3D permitió analizar en retrospectiva con una visión idéntica a la del cirujano durante el intraoperatorio, el tipo de CNV.

Comparative Analysis of Surgical Working Corridors for Meckel Cave Trigeminal Schwannomas: A Quantitative Anatomic Study.

BACKGROUND AND OBJECTIVES: Volumetric analysis of the working corridors of the interdural approach to the Meckel cave may lead to a selection of routes which are anatomically more advantageous for trigeminal schwannoma resection. The herein-reported anatomic study quantitively compares the infratrochlear (IT) transcavernous, anteromedial (AM), and anterolateral (AL) corridors, highlighting their feasibility, indications, advantages, and limitations. METHODS: Anatomic boundaries and depth of Meckel cave, porus trigeminus, IT transcavernous, AM, and AL corridors were identified in 20 formalin-fixed latex-injected cadaveric heads and were subsequently measured. The corridor areas and volumes were derived accordingly. Each opening angle was also calculated. Angles and volumes were compared using analysis of variance. Statistical significance was set at a P -value <.05. RESULTS: The IT transcavernous corridor volume was greater than that of the AM and AL. The opening angle of the AM middle fossa triangle was wider than the other 2. CONCLUSION: The IT corridor can be advantageous for Meckel cave schwannomas invading the cavernous sinus and those with a notable extension into the posterior fossa because the transcavernous approach maximizes the working space into the retrosellar area. The AM middle fossa corridor is strategic in schwannomas confined to the Meckel cave with a minor extension into the posterior fossa. It raises the chance of total resection with a single approach involving the porus trigeminus opening.

Guanti bianchi technique for resection of selected pituitary adenomas.

Introduction: Since the introduction of the endoscopic endonasal approach (EEA) to skull base, the nasal phase has been a true challenge as it represents the moment of definition of the corridor, thus defining the instruments maneuverability at tumor removal phase. The longstanding cooperation between ENT and neurosurgeons have provided the possibility of creating adequate corridor with maximal respect toward nasal structures and mucosa. This sparked the idea of entering the sella as thieves, so we named "Guanti Bianchi" technique a lesser invasive variation of the approach for the removal of selected pituitary adenoma. Research Question: The purpose of this study is to present the preliminary results of "Guanti Bianchi" technique. Material and Methods: Data from 17 patients undergoing "Guanti Bianchi" technique (out of 235 standard EEA) at our center, were retrospectively analysed. ASK Nasal-12, a quality-of-life instrument developed specifically to assess patient perception of nasal morbidity, was administered pre- and postoperatively. Results: 10 (59%) patients were men and 7 (41%) women. The mean age was 67.7 (range 35-88). The average duration of the surgical procedure was 71.17 minutes (range 45-100). GTR was achieved in all patients, no postoperative complications were observed. Baseline ASK Nasal-12 was near normal in all patients, 3/17 (17,6%) experienced transitory very mild symptoms without any worsening at 3 and 6 months. Discussion and Conclusions: This minimally invasive technique does not require turbinectomy or carving of the nasoseptal flap, it alters the nasal mucosa as little as necessary, and it is quick and easy to perform.

A simple technique for generating 3D endoscopic images.

Background: Most neurosurgical photographs are limited to two-dimensional (2D), in this sense, most teaching and learning of neuroanatomical structures occur without an appreciation of depth. The objective of this article is to describe a simple technique for obtaining right and left 2D endoscopic images with manual angulation of the optic. Methods: The implementation of a three-dimensional (3D) endoscopic image technique is reported. We first describe the background and core principles related to the methods employed. Photographs are taken demonstrating the principles and also during an endoscopic endonasal approach, illustrating the technique. Later, we divide our process into two sections containing explanations, illustrations, and descriptions. Results: The results of taking a photograph with an endoscope and its assembly to a 3D image has been divided into two parts: Photo acquisition and image processing. Conclusion: We conclude that the proposed method is successful in producing 3D endoscopic images.

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.

Single-Stage Complete Removal of Dumbbell-Shaped Trigeminal Schwannoma: 3-Dimensional Operative Video.

Intracranial trigeminal schwannomas are rare tumors that may extend into multiple cranial compartments and may emerge from the root, ganglion, or intracranial portion of any of its branches.1-6 The aim of this 3-dimensional operative video is to present a single-stage complete removal of a dumbbell-shaped trigeminal schwannoma through a pretemporal approach (Video 1). Informed consent was given by the patient for use of images and the surgical video. We describe the case of a 43-year-old female presenting with chronic headaches and left facial pain in the trigeminal territory of V2 and V3. Magnetic resonance imaging showed a tumoral lesion located within the cerebellopontine angle, petroclival region, and middle fossa. Due to the patient's symptoms, tumor size, and growth on sequential imaging, single-stage surgical removal was determined through a frontotemporal approach. There were no adverse outcomes posterior to the surgery, and the patient evolved favorably without neurologic deficits. Postoperative imaging showed complete resection of the tumoral lesion. Presurgical planning is essential for an effective and safe surgical strategy. For cases of trigeminal schwannomas with extension to the middle and posterior fossa, single-stage surgery is feasible for complete and safe removal.

Microneurosurgical management of aneurysms of the A1 segment of the anterior cerebral artery: Anatomy and surgical technique.

Background: Aneurysms of the A1 segment of the anterior cerebral artery (ACA) are rare and have characteristics differentiating them from other intracranial aneurysms. Their microsurgical management is challenging and requires different strategies. In this article, we review the surgical anatomy of the A1 segment of the ACA with cadaveric dissections and describe the microsurgical management of complex A1 aneurysms with illustrative cases. Methods: A right pterional craniotomy and Sylvian dissection were performed on a formalin-fixed and silicone-injected cadaver head to depict the key anatomic structures and surgical corridors for microsurgical clipping of A1 segment aneurysms. The microneurosurgical management of ruptured and unruptured aneurysms of the A1 segment of the ACA is described with case illustrations. Results: The A1 segment of the ACA can be subdivided into proximal, middle, and distal subsegments, the former having abundant perforating branches. Both patients treated with microsurgical clipping had excellent and durable outcomes and postoperative cerebral angiograms showed complete aneurysm occlusion. Conclusion: Small A1 aneurysms may require early treatment as their rupture risk appears to be higher. A1 aneurysms are usually embedded in perforators, especially those arising from the proximal A1 subsegment, and require careful distal to proximal microdissection and strategic placement of the aneurysm clip blades. The approach, arachnoid dissection, and angles of attack are carefully planned after accounting for the aneurysm dome projection, precise location of the aneurysm neck and perforators, and the presence or absence of subarachnoid hemorrhage.

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.

Piggyback Stacking and Booster Clipping Technique: A Technical Note.

In certain cases, the closing force of a single vascular clip is not sufficient for complete aneurysmal occlusion, and the use of multiple clips, or clip stacking, is required. Many stacking techniques have been described in the literature, such as in tandem stacking and overstacking. However, these may not be feasible during procedures with limited exposure or narrow corridors. Clip reinforcement with a second high-pressure booster clip, also known as the piggyback technique, is an alternative for these cases along with anatomically complex aneurysms or aneurysms demonstrating atypical morphological features. Although this technique has been cited as a potential resource for certain aneurysms, descriptions of its characteristics and advantages are scarce. The purpose of this technical note was to discuss our experience with the piggyback clipping technique and use of a booster clip for a partially embolized and recanalized saccular posterior communicating artery aneurysm in a 50 year-old patient.

Contralateral Interhemispheric Transfalcine Approach for Supratentorial Extraventricular Ependymoma Resection.

BACKGROUND/AIM: Extraventricular supratentorial ependymomas are rare entities. Most ependymomas are located at the infratentorial and intraventricular level, and only in a small group of cases they do not present continuity with the ventricular system. This is a case report of a patient with an atypical location of a cerebral ependymoma, which required the implementation of a complex and infrequent approach for its complete microsurgical removal. CASE REPORT: A 16-year-old male patient was referred at our department with a diagnosis of a 40 mm × 50 mm × 60 mm solid-cystic space-occupying lesion, sited between the left superior frontal-cingulate gyri. A contralateral transfalcine interhemispheric approach was selected, which achieved total resection of the tumor. The histopathological diagnosis of Grade II ependymoma was obtained according to WHO classification. CONCLUSION: The contralateral transfalcine interhemispheric approach represents a favorable surgical corridor to achieve a total resection of the tumor lesion and is favored by an adequate working angle and reduced brain manipulation.

Supracerebellar Transtentorial Approach for Posterior Temporomesial Cavernoma: 3-Dimensional Operative Video.

The temporomesial region is a frequent site of neurosurgical lesions such as tumors, cavernomas, or arteriovenous malformations. This region has been divided into 3 regions: anterior, middle, and posterior.1-4 The objective of Video 1 is to present the case of a posterior temporomesial cavernoma resection through a supracerebellar transtentorial approach, highlighting the surgical technique. The case is a 50-year-old female with history of temporomesial bleeding, headaches, and seizures refractory to medical treatment. In the neuroimaging studies a posterior temporomesial image was diagnosed. We selected a paramedian supracerebellar transtentorial approach in semisitting position for the surgery. With the use of neuronavigation guidance, the cavernoma was located and removed in 1 piece. The patient evolved favorably, without neurologic deficit, improving the symptoms after surgery. The approach is an excellent alternative for exposing the temporomesial region, and the semisitting position facilitates the retraction by gravity of the cerebellum, maintaining a clean surgical field during the microsurgical procedure.3-5.

Classification and Management of Pontecerebellar-Petrosal Bridging Veins.

OBJECTIVES: The risks and benefits of coagulating intradural venous elements during a retrosigmoid approach for trigeminal neurovascular decompression has not been accurately established. The objectives of this study were to identify the veins that drain into the superior petrosal sinus, classify them in relation to the suprameatal tubercle, and determine the implication of their coagulation. METHODS: A retrospective study of 3-dimensional surgical videos of retrosigmoid approaches for trigeminal neurovascular decompression from the Laboratory of Neurosurgical Innovations of Tucumán (LINT) digital archive was carried out. The veins encountered were classified into 3 groups: retromeatal, meatal and premeatal. The neurosurgical postoperative complication scale proposed by Landriel et al. was utilized to assess complications from venous coagulation. A grade 0 was added for patients without complications. The STATA 14 program was utilized for statistical analysis. RESULTS: The pontocerebellar-petrosal veins of 28 patients who underwent trigeminal decompressive surgery were analyzed. In 7 cases these were found in the retromeatal region; 100% were sacrificed. Eleven cases revealed veins within the meatal region; 90.91% were coagulated. Veins in the premeatal region were found in 14 cases; 57.14% were sacrificed. In the postoperative follow-up, 27 patients were grade 0 and 1 patient developed postoperative meningitis (grade Ib complication). No patient suffered vascular complications. CONCLUSIONS: The venous elements identified in trigeminal neurovascular decompressive surgery are variable. We propose classifying them into retromeatal, meatal, and premeatal groups. Retromeatal and meatal veins can be safely sacrificed for appropriate visualization of the neurovascular conflict. The premeatal venous elements should be coagulated only in justified cases.

Optic Foraminotomy for Clipping of Superior Carotid-Ophthalmic Aneurysms.

Background: Carotid-ophthalmic aneurysms usually cause visual problems. Its surgical treatment is challenging because of its anatomically close relations to the optic nerve, carotid artery, ophthalmic artery, anterior clinoid process, and cavernous sinus, which hinder direct access. Despite recent technical advancements enabling risk reduction of this complication, postoperative deterioration of visual function remains a significant problem. Therefore, the goal of preserving and/or improving the visual outcome persists as a paramount concern. Objective: We propose optic foraminotomy as an alternative microsurgical technique for dorsal carotid-ophthalmic aneurysms clipping. As a secondary objective, the step by step of that technique and its benefits are compared to the current approach of anterior clinoidectomy. Methods: We present as an example two patients with superior carotid-ophthalmic aneurysms in which the standard pterional craniotomy, transsylvian approach, and optic foraminotomy were performed. Surgical techniques are presented and discussed in detail with the use of skull base dissections, microsurgical images, and original drawings. Results: Extensive opening of the optic canal and optic nerve sheath was successfully achieved in all patients allowing a working angle with the carotid artery for correct visualization of the aneurysm and further clipping. Significant visual acuity improvement occurred in both patients because of decompression of the optic nerve. Conclusion: Optic foraminotomy is an easy and recommended technique for exposing and treating superior carotid-ophthalmic aneurysms and allowing optic nerve decompression during the first stages of the procedure. It shows several advantages over the current anterior clinoidectomy technique regarding surgical exposure and facilitating visual improvement.

Complete Removal of Bilateral Clinoidal Meningiomas Through a Pterional Approach: 3-Dimensional Operative Video.

Surgical removal of anterior clinoidal meningiomas remains a challenge because of its complicated relationship with surrounding vascular and neural structures.1-3 This is a 39-yr-old female, with headaches, neurofibromatosis type 2, and history of 3 previous brain surgeries. The patient gave the consent to use the images and surgical video. In the imaging control, the growth of bilateral anterior clinoidal meningiomas was observed. A right pterional approach and extradural anterior clinoidectomy was performed, and a complete resection of bilateral clinoidal meningiomas was achieved obtaining a Simpson scale resection grade 1. The patient evolved without neurological deficits after the surgery, and the postoperative magnetic resonance imaging (MRI) evidenced a complete bilateral resection of the clinoidal meningiomas. Clinoidal meningiomas are the unique subset of tumors because of their close proximity to neurovascular structures and can be safely excised with minimal morbidity and mortality using microsurgical techniques.3-5 In rare cases of bilateral anterior clinoidal meningiomas such as the case presented, we recommend detailed neuroimaging analysis and consider the possibility to resect both in a single approach.

Meningiomas de fosa posterior: nomenclatura con orientación anatomo-quirúrgica y presentación de casos ilustrativos / Posterior fossa meningiomas: nomenclature with anatomical-surgical orientation and presentation of illustrative cases

Introducción: Los meningiomas de la fosa posterior representan el 20% de todos los meningiomas intracraneales. Cada subtipo tiene una base de implantación, abordaje quirúrgico y morbimortalidad postoperatoria muchas veces diferente. Advertimos que en reuniones científicas y publicaciones no se sigue una forma de clasificar uniforme, sencilla y clara con orientación netamente quirúrgica. Esto genera que el neurocirujano en formación no cuente con herramientas suficientes para la toma de decisiones. Objetivos: Proponer una clasificación sencilla de los meningiomas de la fosa posterior con un fundamento anatomo-quirúrgico y presentar casos ilustrativos de cada subtipo. Materiales y métodos: Se estableció una nomenclatura considerando reportes previos, el criterio anatómico y la experiencia quirúrgica de los autores. Se presentaron casos revisando las historias clínicas y los archivos de imágenes correspondientes a cada subtipo de la clasificación. Resultados: Representamos a la fosa posterior como un compartimento con 3 anillos: el superior se divide en medial, lateral-anterior y lateral-posterior; el medio se divide en 6 variantes: clivales puros, esfeno-petro-clivales, petrosos anteriores, petrosos posteriores y de la convexidad suboccipital medial y lateral; el inferior se divide en anterior, lateral derecho, lateral izquierdo y posterior. Conclusión: Los meningiomas del anillo superior pueden resolverse mediante una vía suboccipital medial o lateral; los del anillo medio tienen un espectro de opciones más diverso; los del anillo inferior -siguiendo el esquema de división en cuadrantes de un reloj- pueden resolverse por medio de un abordaje suboccipital medial o extremolatera

Introduction: Posterior fossa meningiomas represent 20% of all meningiomas, being each location associated with a specific approach, morbidity and mortality. The actual classifications are focus on the dural attachment, without associating the anatomical with the surgical aspects, useful to the young neurosurgeons for decision making. Objectives: To propose a classification of the posterior fossa meningiomas with an anatomical-surgical view including the presentation of cases. Materials and Methods: A nomenclature was established concerning previous reports, the anatomical criteria and the surgical experience of the authors. Cases were presented by reviewing the medical records corresponding to each subtype of the proposed classification. Results: We represent the posterior fossa as a 3 rings compartment: the upper one is divided into medial, anterior-lateral and posterior-lateral; the middle ring is divided into 6 variants: pure clival, spheno-petro-clival, anterior petrosal, posterior petrosal, and medial and lateral suboccipital convexity; the lower ring is divided into anterior, right lateral, left lateral, and posterior. Conclusion: Superior ring meningiomas can be resolved by a medial or lateral suboccipital approach; middle ring meningiomas have a more diverse spectrum of options; while meningiomas of the inferior ring - following the scheme of division into quadrants of a clock - can be resolved by means of a medial or extreme-lateral suboccipital approach.

Transcondylar Fossa Approach for Resection of Anterolateral Foramen Magnum Meningioma: 2-Dimensional Operative Video.

Among the posterolateral corridors to the ventral foramen magnum (FM), the transcondylar fossa (supracondylar transjugular tubercle) approach (TCFA) is indicated for lesions lying anteriorly to the dentate ligament and above the jugular foramen and hypoglossal canal.1-13 It involves the drilling of the condylar fossa, namely the exocranial surface of the jugular tubercle. Despite the anatomic variability of the condyle and posterior condylar emissary vein,14,15 they are important landmarks for the TCFA. The extradural jugular tuberculectomy has no risk of iatrogenic mechanical instability compared with the transcondylar approach. This 2-dimensional operative video (Video 1) aims to show the key technical aspects of the TCFA through the case description of an anterolateral FM meningioma. A 35-year-old male patient with a left anterolateral FM meningioma underwent TCFA in a semisitting position. Drilling of the condylar fossa led to an extradural resection of the jugular tubercle. Posterior condylar emissary veins connecting the sigmoid sinus/jugular bulb with the vertebral venous plexus marked the lateral limit of the approach. Through a suprahypoglossal working corridor, the meningioma was debulked and dissected. Postoperative magnetic resonance imaging confirmed complete resection of the tumor, and the patient was discharged neurologically intact on the third postoperative day. TCFA is a valuable technical option for selected anterolateral FM meningiomas. The perfect knowledge and intraoperative use of specific anatomic landmarks are critical to safely perform the TCFA while maximizing the exposure of the surgical target and decreasing the risk of postoperative mechanical instability of the craniovertebral junction.

Risk factors for surgical site infection in pediatric posterior fossa tumors.

PURPOSE: Posterior fossa tumors are the most frequent pediatric solid tumor. Its main treatment is a surgical resection. Being a frequent procedure does not mean that it is exempt from complications, such as surgical site infections (SSI). The main objective of this paper is to study the risk factors associated with SSI following a resection of posterior fossa tumors in a purely pediatric population. METHODS: A retrospective case-control study including all posterior fossa tumor surgeries performed at our hospital between January 2014 and December 2019 was conducted. All patients with a diagnosis of a postoperative SSI have been included as cases, and those who had surgery and no infectious complications have been considered as controls. RESULTS: When analyzing risk factors, we have found that patients with ventriculoperitoneal shunt (VPS) (p = 0.03) or external ventricular drainage (EVD) (p = 0.005) placement had a greater chance of presenting a postoperative surgical site infection. Prolonged operative time (p < 0.001) and cerebrospinal fluid (CSF) leak through the wound (p = 0.002) also caused an increase in the risk of SSI in the postoperative period. A higher hemoglobin value (p = 0.002) would seem to be a preventive factor. CONCLUSIONS: Some strategies that could help to reduce the risk of infections are managing hydrocephalus preferably with endoscopic third ventriculostomy, minimizing the needed operative time to perform the procedure, obtaining an adequate serum hemoglobin level, and avoiding CSF leak through the wound.