Gangliogliomas in the pediatric population.

BACKGROUND: Gangliogliomas are neoplastic lesions composed by a mixed population of neoplastic glial and dysplastic neural cells. They represent around 5% of all CNS tumors in the pediatric population. These usually are well-differentiated, slow-growing tumors, meaning that complete resection could cure most of these patients. Although most lesions remain stable over time after incomplete resection, some patients develop progression of the residual lesions: the optimal approach to treat these tumors is still to be defined. METHODS: This is a retrospective study in which we obtained data from medical records of pediatric patients who had a histological diagnosis of ganglioglioma following surgical treatment at a single center between 2001 and 2020. RESULTS: We included 17 pediatric subjects with gangliogliomas. The median age at diagnosis was 6.7 years, and the median follow-up duration was 60 months. The most common clinical presentation was epileptic seizures (41.1%). Hydrocephalus was present in 29.4% of cases. 52.9% of tumors involved exclusively the cerebral hemispheres, with the temporal lobe being the most affected location. Gross total tumor resection (GTR) was accomplished in 47% of all cases and in 75% of hemispheric tumors. Of patients, 33% in whom GTR could not be achieved showed progression of the residual tumor. BRAF V600E mutation was present in 44.4% of cases. CONCLUSION: Gangliogliomas are typically grade I tumors that occasionally affect children. They classically localize in the cerebral hemisphere but may involve deep structures like the basal ganglia, brain stem, and cerebellum, which seems to be particularly frequent in the pediatric population, implying further challenge to achieve adequate oncological control with surgery as the only treatment modality. Although most cases in which GTR could not be performed remained stable over the follow-up, significant progression of the tumor remains was observed in some patients. BRAF inhibitors should be considered as a feasible treatment option in this setting.

Laparoscopy-assisted placement of a ventriculobiliary shunt: a technical note.

PURPOSE: Hydrocephalus is a common condition in pediatric neurosurgeon's clinical practice. Peritoneal and atrial shunting is the treatment of choice in the immense majority of patients. Sometimes, there are complex cases that may need innovative solutions in order to implant the distal catheter of the shunt: in these situations, the gallbladder is a well-described option and it can be safely used. METHODS: We report the case of a 4-month-old baby with a wide optic-chiasmal hypothalamic glioma generating hydrocephalus with high protein values in CSF. Ventriculobiliary shunting was decided, and the distal catheter was directed by the assistance of laparoscopic surgery. RESULTS: The outcome was satisfactory. CONCLUSIONS: As far as we know, laparoscopic placement of a distal catheter in the gallbladder has not been described in the literature; herein, we describe the tenets and the technical tips of this approach.

Transantral endoscopic approach for the treatment of lesions affecting the maxillary nerve.

BACKGROUND: Surgical approaches to skull base lesions that affect the maxillary nerve are complex, due to deep location and presence of relevant neurovascular structures surrounding this area. METHOD: We propose the transantral endoscopic approach (TEA) for the treatment of lesions affecting the maxillary nerve or its vicinity. More specifically, the ones that are located anterior to the foramen rotundum. CONCLUSIONS: This technique represents a minimally invasive treatment option for these kind of cranial base lesions. It offers optimal visualisation similar to the endonasal approach, whereas less dissection is required.

Full endoscopic endonasal transsellar-transclival approach: the modularity concept.

BACKGROUND: Endoscopic endonasal approaches (EEAs) constitute a reasonable option for the treatment of lesions that involve the sellar and clival regions. METHODS: We describe, step by step, the full EEA expanded to the middle and lower clivus for the treatment of perisellar lesions. Delimiting different modules around the sellar region is useful in establishing the best endoscopic approach for each tumor. A craniopharyngioma (CP) with clival extension will be used as an illustrative example of the modularity concept of these approaches. CONCLUSIONS: Transsellar-transclival EEA allows complete resection of lesions located in the sellar and infrasellar region with a low rate of complications.

Endo ICG videoangiography: localizing the carotid artery in skull-base endonasal approaches.

BACKGROUND: In this work, the applicability of ICG-VA to skull base endoscopic surgery and its capacity to locate the internal carotid artery are shown. METHODS: An adapted optical module to perform ICG-VA was used to perform endoscopic procedures. There were two intraoperative phases of interest that were used to evaluate the ICA: upon exposure of the skull base and during the intradural exploration. This new tool for obtaining ICA images in real time (as opposed to with navigation), and it is demonstrated that this tool provides a superior ability to detect the margins of the ICA compared with the Doppler technique. On the other hand, the present technique also provides enhancement of the artery through the bone of the skull base without the need for drilling. CONCLUSIONS: ICG-VA is a safe and effective technique for locating the ICA in skull-base expanded endonasal surgery. Furthermore, this technique can provide real-time guidance for the surgeon and increase safety for the patient.

Indocyanine green videoangiography methodological variations: review.

Indocyanine green videoangiography (ICGVA) procedures have become widespread within the spectrum of microsurgical techniques for neurovascular pathologies. We have conducted a review to identify and assess the impact of all of the methodological variations of conventional ICGVA applied in the field of neurovascular pathology that have been published to date in the English literature. A total of 18 studies were included in this review, identifying four primary methodological variants compared to conventional ICGVA: techniques based on the transient occlusion, intra-arterial ICG administration via catheters, use of endoscope system with a filter to collect florescence of ICG, and quantitative fluorescence analysis. These variants offer some possibilities for resolving the limitations of the conventional technique (first, the vascular structure to be analyzed must be exposed and second, vascular filling with ICG follows an additive pattern) and allow qualitatively superior information to be obtained during surgery. Advantages and disadvantages of each procedure are discussed. More case studies with a greater number of patients are needed to compare the different procedures with their gold standard, in order to establish these results consistently.

Brain abscess as the initial presentation of a macroprolactinoma: Case report.

Macroprolactinomas may behave invasively and infiltrate the skull base, causing a subsequent thinning that can also lead to a bone defect and a direct route of entry for pathogens. We describe the case of a 34-year-old male admitted to hospital with fever (38°C), headache, stiffness in the neck, diplopia and neurological impairment. Brain magnetic resonance imaging showed two bilateral abscesses in the fronto-parietal areas with intracranial venous sinus thrombosis and a pituitary adenoma that extended from the suprasellar region, eroding the sellar floor into the sphenoid sinus. Laboratory hormone measurements showed increased levels of prolactin and low levels of FSH, LH and testosterone. The patient received antibiotic treatment and surgery was performed. The patient developed central deafness as a neurological deficit. It is advisable to include pituitary adenoma in the differential diagnosis of meningitis even though its onset as intracranial abscess and rectus sinus thrombosis is extremely rare.

Full endoscopic endonasal expanded approach to the petroclival region: optimizing the carotid-clival window.

BACKGROUND: The petroclival junction (PCJ) is a challenging skull base location from neurosurgical point of view, especially if the retrocarotid space has to be reached. METHOD: In response to this challenge, this report provides a detailed full description of the endoscopic endonasal expanded approach (EEA) to the petroclival region and retrocarotid space. We present the technique step by step, introducing a critical concept about the optimization of the petroclival drilling, generating the carotid-clival window (CCW). The CCW is delimited by the paraclival segment of the internal carotid artery ICA anterolaterally, the petrous bone posterolaterally, the clival dura medially, the synchondrosis inferiorly, and the cavernous sinus superiorly; therefore, this approach exposes an important nuance to augment the previous approaches for PCJ and retrocarotid space. CONCLUSION: This technique provides a good surgical window and carries minimal risk.

Full endoscopic endonasal suprapetrous approach to Meckel's cave.

BACKGROUND: Meckel's cave is an anatomically complex region that can be approached surgically via several routes, namely the posterolateral, lateral, anterolateral, and, due to recent advancements, anteromedial routes, with the latter being represented by the expanded endonasal approaches. METHOD: We describe in detail the surgical technique of the suprapetrous endonasal approach to Meckel's cave and highlight the main anatomical key elements involved in this approach as well as the technical aspects for avoiding surgical complications. CONCLUSION: The suprapetrous endonasal approach to Meckel's cave avoids the brain tissue retraction, and thereby prevents postoperative brain edema.

[Sacral metastasis simulating aneurysmal bone cyst]. / Metástasis sacra simulando quiste óseo aneurismático.

Cystic spinal lesions with characteristic patterns, such as the presence of haematic fluid-fluid levels (H-FFL), have been associated with many tumoral lineages, more frequently with aneurysmal bone cyst (ABC) and exceptionally with metastasis. We present the case of a 60-year-old man with the finding of a sacral cystic bone lesion with H-FFL, with initial suspicion of ABC and confirmed diagnosis of metastasis. The case presented is, to our knowledge, the second case published of spinal cystic bone metastasis with H-FFL pattern with unknown primary tumour at the time of diagnosis and the only one that received resective surgical treatment, achieving pulmonary and metastatic disease control with good quality of life after 1 year of follow up.

Microscopic versus endoscopic pituitary surgery.

INTRODUCTION AND OBJECTIVE: The endoscopic techniques used in pituitary surgery have evolved greatly in recent years. Our objective in this study was to conduct a review of the systematic reviews published in the English language literature, to examine their consistency and conclusions reached following studies comparing microsurgery and endoscopic surgery in hypophyseal surgery. MATERIALS AND METHODS: We carried out a bibliographic search on MEDLINE and EMBASE electronic databases, selecting those systematic reviews and meta-analyses published from the year 2000 until January 2013, focusing on comparisons between microsurgical and endoscopic techniques. RESULTS: We concluded with type A consistency that hospital stay was shorter and diabetes insipidus and rhinological complications were less frequent in the endoscopy group. We concluded with type B consistency that lower rates of patient blood loss, shorter operative times, higher rate of gross total resection, lesser association to visual impairment and lower rate of hypopituitarism were observed in the endoscopy group. Vascular complications and cerebrospinal fluid fistulas were reduced with microsurgery. It is crucial to perform a combined analysis of all the systematic reviews treating a specific topic, observing and analysing the trends and how these are affected by new contributions. CONCLUSION: Randomized multicenter studies are necessary to resolve the controversy over endoscopic and microsurgical approaches in hypophyseal pathology.

Full endoscopic endonasal transclival approach: meningioma attached to the ventral surface of the brainstem.

BACKGROUND: Intracranial meningiomas without dural attachment (MWODA) are rare entities. We present the first case published, to the best of our knowledge, regarding a MWODA attached to the ventral surface of the brainstem. This location makes the patient subsidiary to treatment through an expanded endonasal transclival approach. CLINICAL PRESENTATION: A 16-year-old female with suspected diagnosis of recurrence of a clear cell meningioma (CCM) at a distance from the initial lesion, located on the premedullary cistern. The patient underwent a pure endoscopic low transclival approach. The attachment to the ventral surface of the brainstem was confirmed intraoperatively. Postoperative MRI confirmed gross total resection and treatment was complemented with adjuvant fractionated stereotactic radiotherapy. No complications related to the procedure were observed. CONCLUSION: MWODA may appear attached to the ventral brainstem. The expanded endonasal approach to the clivus provides a critical anatomical advantage in the treatment of medial lesions, even ventral meningiomas, to the lower cranial nerves. Reconstruction principles must be strictly respected to reduce complications.

Indocyanine green videoangiography "in negative": definition and usefulness in spinal dural arteriovenous fistulae.

PURPOSE: Indocyanine green videoangiography (IGV) has proven its effectiveness in the field of exovascular neurosurgery, both in the intracranial and spinal compartment, but is necessary to define a systematic process for the performance of the IGV to facilitate its interpretation during the procedure. We have defined and applied the concept of videoangiography "in negative" (INIGV) to spinal dural arteriovenous fistulae (dAVF) for the detection and treatment of arteriovenous shunts, so called because the first phase is performed with the vessel suggestive of being pathological occluded. METHODS: A Pentero-operating microscope with near-infrared IGV-integrated system (Carl Zeiss Co., Germany) was used. At our institution, 24 patients were treated for a spinal dAVF between 1995 and 2011, only in the last 4 cases, INIGV was performed. RESULTS: We describe the IGV in negative procedure and show the most illustrative cases. In all cases, the fistula occlusion was confirmed by postoperative selective digital subtraction angiography (DSA). INIGV demonstrate its capacity in detecting vessels not actually arterialized that should be respected and avoid some of the main limitations of the conventional IGV. This is a technical description about an Indocyanine green (ICG) videoangiographic procedure modification that is superior to merely performing ICG before and after clipping of a dAVF. CONCLUSION: The INIGV results are rapid and easy to interpret procedure and provide great advantages to the dAVF treatment. Nevertheless, further studies are needed with a larger sample size to determine if INIGV may reduce the need to perform immediate postoperative DSA.

Primary extraosseous intradural spinal Ewing's sarcoma: report of two cases.

Two cases of primary extraosseous intradural spinal Ewing's sarcoma are reported with a review of the current literature. This rare neoplasm shares features with cerebral primitive neuroectodermal tumors, complicating a correct diagnosis. Gross total resection seems to be the main treatment, although adjuvant therapies could improve the prognosis. In case 1, a 56-year-old man presented with cauda equina syndrome. MRI showed an intradural tumor from L4 to S2. An emergency laminectomy was performed with gross total resection of a hemorrhagic tumor, followed by adjuvant treatment. In the second case, a 25-year-old female developed leg and lumbar pain. MRI study identified a homogeneously enhancing intradural mass at the L2-L3 level. A laminoplasty was performed, followed by tumor resection; no adjuvant treatment was administered afterwards. Immunohistochemical workup confirmed the diagnosis of Ewing's sarcoma in both cases.

[Endonasal skull base endoscopy]. / Endoscopia endonasal de base de cráneo.

INTRODUCTION AND OBJECTIVE: The endoscopic endonasal techniques used in skull base surgery have evolved greatly in recent years. Our study objective was to perform a qualitative systematic review of the likewise systematic reviews in published English language literature, to examine the evidence and conclusions reached in these studies comparing transcranial and endoscopic approaches in skull base surgery. MATERIAL AND METHODS: We searched the references on the MEDLINE and EMBASE electronic databases selecting the systematic reviews, meta-analyses and evidence based medicine reviews on skull based pathologies published from January 2000 until January 2013. We focused on endoscopic impact and on microsurgical and endoscopic technique comparisons. RESULTS: Full endoscopic endonasal approaches achieved gross total removal rates of craniopharyngiomas and chordomas higher than those for transcranial approaches. In anterior skull base meningiomas, complete resections were more frequently achieved after transcranial approaches, with a trend in favour of endoscopy with respect to visual prognosis. Endoscopic endonasal approaches minimised the postoperative complications after the treatment of cerebrospinal fluid (CSF) leaks, encephaloceles, meningoceles, craniopharyngiomas and chordomas, with the exception of postoperative CSF leaks. CONCLUSIONS: Randomized multicenter studies are necessary to resolve the controversy over endoscopic and microsurgical approaches in skull base surgery.

[Transpterygoid expanded endonasal approach in fibrous dysplasia of the skull base: case report and technical note]. / Abordaje endonasal expandido transpterigoideo en la displasia fibrosa de base de cráneo: caso clínico y nota técnica.

INTRODUCTION: Expanded endonasal approaches (EEA) are becoming a first-level technique for the treatment of skull base pathologies. In some cases, the endoscopic procedures make it possible to dissect structures manipulated with greater difficulty in the classic approaches. We report a full endoscopic transpterygoid EEA for the treatment of a fibrous dysplasia (FD) of the skull base. In addition, we reviewed the English literature available on FD and transpterygoid EEA, establishing an exact surgical technique and showing our intraoperative experience. CASE REPORT: A 42-year-old male with right sixth cranial nerve palsy. Cranial MRI and CT showed a central skull base lesion with diagnostic suspicion of FD. Patient underwent a full endoscopic transpterygoid EEA, achieving a wide skull base neurovascular decompression. Neuronavigation and the vidian canal landmark resulted mandatory during intraoperative procedure. DISCUSSION: The transpterygoid EEA is a safe technique consistently supported in the literature. It may reduce the morbidity associated to the classic transcranial approaches, since it permits maximum resection with minimum craniofacial distortion. The vidian hole and canal are the landmarks used to locate and avoid injury to the lacerum segment of the carotid injury. The surgical treatment indication in FD cases must be established in symptomatic patients. CONCLUSION: Transpterygoid EEA for treatment of FD of the skull base is a safe and effective procedure, thanks to the guide that the vidian canal provides in finding the lacerum segment of the carotid artery.

[Esthesioneuroblastoma. Transcribiform-transfovea ethmoidalis endonasal expanded approach. Technical note]. / Estesioneuroblastoma. Abordaje endonasal expandido transcribiforme-transfovea etmoidalis. Nota técnica.

INTRODUCTION: We report a fully endoscopic transcribiform-transfovea ethmoidalis endonasal expanded approach (EEA) for the treatment of esthesioneuroblastoma and review the literature about this entity available in English, establishing a precise surgical technique and describing our intraoperative experience. CASE REPORT: Our patient was a 65-year old female with anosmia and cognitive deterioration. Cranial MRI showed a large tumoral lesion with solid and cystic components involving the nasal cavity, with diagnostic suspicion of intracranial malignant sinonasal tumour. The patient underwent a fully endoscopic transcribiform-transfovea ethmoidalis EEA, achieving total resection and tumour-free margins. Surgery was followed by radiotherapy. DISCUSSION: Craniofacial resection enables total removal of sinonasal malignancies, even when the intracranial cavity is involved, and allows for subarachnoid space isolation from the nasal cavity. New advances in endoscopic skull base surgery have achieved comparable oncological results and sufficient reconstructive capacity, leading to less morbidity and better tolerance. CONCLUSION: EEA may become the first treatment option for skull base malignancies in an immediate future, provided that the anatomical limits of the extended approach are not exceeded by the lesion.

Septal rhinopharyngeal flap: a novel technique for skull base reconstruction after endoscopic endonasal clivectomies.

Endoscopic endonasal reconstruction techniques have improved CSF leak rates that were initially reported after surgery for cranial base and intradural lesions. However, wide surgical defects still pose a problem, especially if located in the clival region. The authors propose and describe a novel reconstruction technique they call a septal rhinopharyngeal flap (SRF) specifically designed to address this issue. The SRF is formed by three components of mucosa: 1) septal, 2) rhinopharyngeal roof, and 3) rhinopharyngeal posterior wall components, which allows for the coverage of the tuberculum/sellar region, midclivus, and lower clivus, respectively. A step-by-step procedure is described and its results analyzed in cases in which it has been used. The SRF was performed in 8 patients, which included diagnoses of 4 chordomas, 2 petroclival meningiomas, 1 invasive pituitary adenoma, and 1 chondrosarcoma. The size of the flap was considered optimal in all patients (100%). Postoperative MRI revealed contrast enhancement covering the entire surface of the flap. No CSF leaks were encountered after at least 1 postoperative year. The SRF is a novel vascularized reconstruction technique specifically indicated for wide endosanasal clivectomies focused on the middle clivus with caudal extension into the lower clivus and craniocervical junction, as well as rostral extensions into the tubercular or planum sphenoidale. This new reconstruction technique could be added to the skull base reconstruction armamentarium as a safe and optimal option.

Middle turbinate vascularized flap for skull base reconstruction after an expanded endonasal approach.

INTRODUCTION: The expanded endonasal approaches to the skull base are modular approaches that arise from the sphenoidal sinus. The reconstructive techniques in these approaches are key to avoid postoperative complications. Available flaps for reconstruction include the pedicled nasoseptal flap, the transpterygoid temporoparietal fascia flap, and the posterior pedicle inferior turbinate flap (PPITF), among others. Recently, the middle turbinate flap has been described in a cadaveric study. We report our preliminary experience in the use of this middle turbinate vascularized flap for skull base reconstruction after expanded endonasal approaches. MATERIAL AND METHODS: Ten patients underwent reconstructive procedures with the mucoperiostial vascularized middle turbinate flap. Capability to cover the defect, closure success, operative time and complications related to the procedure are retrospectively analyzed. RESULTS: A satisfactory closure was obtained in all procedures, and there were no complications related to the technique. Required operative time was similar to the time employed for the nasoseptal flap. CONCLUSIONS: The vascularized middle turbinate flap is a reliable reconstructive technique for the reconstruction of moderate-sized skull base defects. It can be considered either as the first choice of closure or as an alternative to the nasoseptal flap when this is not available. Different flap combinations may facilitate skull base defect reconstruction.

Endonasal Odontoidectomy in Basilar Invagination.

Objective The endoscopic endonasal odontoidectomy (EEO) is emerging as a feasible surgical alternative to conventional microscopic transoral approach. In this article, we show EEO in the basilar invagination (BI) and describe in detail the technical aspects, advantages, and disadvantages of this approach ( Fig. 1 ). Methods We describe EEO using audiovisual material from the neurosurgical department of Hospital Universitari i Politècnic La Fe Valencia database. Results We present the case of a 61-year-old male patient with BI. Initially, we performed suboccipital decompression and occipitocervical fusion. Subsequently, after a no significant neurological improvement and persistent anterior compression, EEO was performed. The postoperative evolution was uneventful and the preoperative neurological deficits were recovered rapidly after surgery Discussion EEO technique enables complete odontoid resection, preventing invasion of aggressive oral bacterial flora, and it is not limited by the mouth opening. As well, it avoids manipulation of the soft palate, therefore evades the risk of velopalatal insufficiency, facilitates immediate oral tolerance, and early extubation. The rostral position of C1-C2 complex in BI could suppose a great advantage in favor the endonasal approaches. Mucoperichondrial vascularized flaps could be obtained to avoid a postoperative cerebrospinal fluid (CSF) leak and facilitate the reepithelization process of the surgical bed. Conclusion EEO may provide a significant anatomic and technical advantage over the trans-oral approach. The link to the video can be found at: https://youtu.be/Td6MDcjCNKk .