360 Degrees Endoscopic Access to and Through the Orbit.

The treatment of pathologies located within and surrounding the orbit poses considerable surgical challenges, due to the intricate presence of critical neurovascular structures in such deep, confined spaces. Historically, transcranial and craniofacial approaches have been widely employed to deal with orbital pathologies. However, recent decades have witnessed the emergence of minimally invasive techniques aimed at reducing morbidity. Among these techniques are the endoscopic endonasal approach and the subsequently developed endoscopic transorbital approach (ETOA), encompassing both endonasal and transpalpebral approaches. These innovative methods not only facilitate the management of intraorbital lesions but also offer access to deep-seated lesions within the anterior, middle, and posterior cranial fossa via specific transorbital and endonasal corridors. Contemporary research indicates that ETOAs have demonstrated exceptional outcomes in terms of morbidity rates, cosmetic results, and complication rates. This study aims to provide a comprehensive description of endoscopic-assisted techniques that enable a 360° access to the orbit and its surrounding regions. The investigation will delve into indications, advantages, and limitations associated with different approaches, while also drawing comparisons between endoscopic approaches and traditional microsurgical transcranial approaches.

Surgical management of advanced sinonasal cancer: a 10-year mono-institutional experience.

Objective: Endoscopic endonasal surgery is effective in the treatment of sinonasal cancers. However, in cases of well-differentiated locally advanced neoplasms as well as recurrences, the most appropriate treatment is debated. The purpose of this study is to report a mono-institutional experience on craniofacial surgery performed in a tertiary-care referral centre. Methods: This was a retrospective analysis of 90 patients treated with transcranial and/or transfacial resection for sinonasal cancer between 2010 and 2020. Outcome measures included overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS) and recurrence-free survival (RFS). Results: The 5-year OS, DSS and DFS were 48.2%, 60.6% and 28.7%, respectively. Factors correlated with prognosis were pT-classification (p = 0.002), histotype (p = 0.012) and dural involvement (p = 0.004). Independent prognostic factors were orbital apex infiltration (p = 0.03), age (p = 0.002) and adjuvant therapy (p = 0.03). Conclusions: When endoscopic endonasal surgery is contraindicated and chemoradiotherapy is not appropriate, craniofacial and transfacial approaches still represent an option to consider, despite the non-negligible morbidity.

Preliminary Experience with 3-Dimensional-Exoscopic Untethering of a Type II Diastematomyelia: Technical Note and Review of the Literature.

OBJECTIVE: To describe the use of a high-definition 3-dimensional (3D) exoscope (VITOM 3D exoscope; KARL STORZ GmbH) for the neurosurgical treatment of a rare pediatric disease, type II diastematomyelia with associated tethered cord. METHODS: A 13-year-old girl who presented with diastematomyelia type II with a tethered cord was surgically treated with the aid of a high-definition 3D exoscope, with a third operator moving and pivoting its arm. Intraoperative monitoring and mapping were arranged. The surgery required a bilateral access to address both the split cord malformation and the tethering of the filum terminale. The filum terminale was identified and cut, and the connective fibrovascular tissue separating the 2 medullary halves was unraveled. These steps were performed with no changes of intraoperative monitoring. Pertinent literature was addressed carefully. RESULTS: The surgery was successful, and the patient was discharged home on the eleventh postoperative day without any complications. The 3-month postoperative magnetic resonance imaging scan demonstrated regular surgical outcomes; no dynamic motor disturbances were reported. To our knowledge, this is the first spinal congenital malformation treated with the use of a 3D exoscope. CONCLUSIONS: The use of 3D exoscope is advancing in spinal surgery, as it provides magnification, stereopsis, lighting, and definition comparable with the operating microscope; the addition of a third operator simplified the operations of moving around the arm, releasing these burdens for the surgeons. Our preliminary experience proved that the use of a 3D exoscope is feasible and safe for the surgical management of a type II diastematomyelia with tethered cord.

A Benefit/Risk Assessment of Intrathecal Ziconotide in Chronic Pain: A Narrative Review.

BACKGROUND: Ziconotide is an intrathecal drug administered for the treatment of chronic pain. The current literature lacks an exhaustive benefit/risk assessment on this drug. We herein focus on Ziconotide's pharmacology and clinical applications. METHODS: Literature research was conducted to identify studies on Ziconotide administration for the treatment of chronic pain, published between January 1990 and March 2023 and located via PubMed, Embase, Medline, Cinahl, and Web of Science, using the following keywords: Ziconotide, Omega conotoxin, Prialt, SNX-111, intrathecal therapy, and neuropathic pain. Only publications written in English were selected. RESULTS: Among the 86 selected studies, we found 4 Randomized Controlled Trials (RCTs) and 3 prospective long-term studies concerning the intrathecal use of Ziconotide as a monotherapy in chronic pain. Other studies described the intrathecal infusion of Ziconotide combined with other drugs. Overall, Ziconotide has been proved to have strong efficacy for relieving chronic pain, although patients with co-morbid psychiatric disorders require a careful monitoring when treated with Ziconotide. CONCLUSIONS: Overall, the use of Ziconotide, as a monotherapy or in conjunction with other therapies for the treatment of chronic pain, was reported to be efficacious. Overall, its use in patients with chronic pain refractory to other pharmacologic agents outweighs the possible adverse consequences, thus resulting in a favorable benefit/risk assessment.

Marsupialization as an alternative to reconstruction in endoscopic skull base surgery. How I do it.

BACKGROUND: To treat extradural solid-cystic lesions of the ventral skull base, a pedicled nasoseptal flap (NSF) maintains patency of the marsupialized cavity and prevents restenosis and cyst recurrence. METHODS: The authors provide a step-by-step description of the surgical technique valid in different lesions of the skull base, all treated via the endoscopic endonasal approach (EEA). The application is demonstrated by an operative video. CONCLUSION: In selected lesions, endoscopic marsupialization using an NSF ensures drainage and ventilation of the surgical cavity. Re-epithelialization provided by a pedicled flap is a viable alternative to multilayer skull base reconstruction.

A pharmacoeconomic analysis from Italian guidelines for the management of prolactinomas.

Background: Prolactinoma, the most common pituitary adenoma, is usually treated with dopamine agonist (DA) therapy like cabergoline. Surgery is second-line therapy, and radiotherapy is used if surgical treatment fails or in relapsing macroprolactinoma. Objective: This study aimed to provide economic evidence for the management of prolactinoma in Italy, using a cost-of-illness and cost-utility analysis that considered various treatment options, including cabergoline, bromocriptine, temozolomide, radiation therapy, and surgical strategies. Methods: The researchers conducted a systematic literature review for each research question on scientific databases and surveyed a panel of experts for each therapeutic procedure's specific drivers that contributed to its total cost. Results: The average cost of the first year of treatment was €2,558.91 and €3,287.40 for subjects with microprolactinoma and macroprolactinoma, respectively. Follow-up costs from the second to the fifth year after initial treatment were €798.13 and €1,084.59 per year in both groups. Cabergoline had an adequate cost-utility profile, with an incremental cost-effectiveness ratio (ICER) of €3,201.15 compared to bromocriptine, based on a willingness-to-pay of €40,000 per quality-adjusted life year (QALY) in the reference economy. Endoscopic surgery was more cost-effective than cabergoline, with an ICER of €44,846.64. Considering a willingness-to-pay of €40,000/QALY, the baseline findings show cabergoline to have high cost utility and endoscopic surgery just a tad above that. Conclusions: Due to the favorable cost-utility profile and safety of surgical treatment, pituitary surgery should be considered more frequently as the initial therapeutic approach. This management choice could lead to better outcomes and an appropriate allocation of healthcare resources.

Ultrahigh-Definition-3-Dimensional Exoscope-Assisted Clipping of a Right Middle Cerebral Artery Unruptured Aneurysm with Indocyanine Green Video Angiography: Operative Video.

Ultrahigh-definition 3-dimensional exoscopes represent an excellent technologic innovation in contemporary neurosurgery. They combine the advantages of operating microscopes and endoscopes, offering excellent magnification and lighting, maintaining a relatively small footprint and optimal ergonomic features.1-5 One of the most interesting employments of exoscopes in neurosurgery is represented by intracranial vascular surgery. Reports in this field are still limited, but recent experience has shown that ultrahigh definition 3-dimensional exoscopes for aneurysm surgery are noninferior to operating microscopes for surgery duration, complication rate, and patient outcomes.6 In addition, many intraoperative techniques such as the indocyanine green videoangiography (ICG-VA) have been successfully implemented to exoscope-based surgery.7 We present herein the case of a 66-year-old woman that came to our attention for the incidental finding of 3 unruptured brain aneurysms. After neurosurgical consultation, the one located at the right middle cerebral artery bifurcation was considered eligible for surgery.8,9 As shown in Video 1, ICG-VA was employed after permanent clipping to allow immediate quality assurance of occlusion and distal vessel integrity. Postoperative course was uneventful, and follow-up examinations demonstrated the complete occlusion of the aneurysm. This report highlights the feasibility of exoscopic-based ICG-VA in vascular neurosurgery, given its ease of use, ergonomics, and excellent quality of vision provided to both surgeons and operating staff.

Italian Guidelines for the Management of Prolactinomas.

INTRODUCTION: This guideline (GL) is aimed at providing a reference for the management of prolactin (PRL)-secreting pituitary adenoma in adults. However, pregnancy is not considered. METHODS: This GL has been developed following the methods described in the Manual of the Italian National Guideline System. For each question, the panel appointed by Associazione Medici Endocrinologi (AME) has identified potentially relevant outcomes, which have then been rated for their impact on therapeutic choices. Only outcomes classified as "critical" and "important" have been considered in the systematic review of evidence and only those classified as "critical" have been considered in the formulation of recommendations. RESULTS: The present GL provides recommendations regarding the role of pharmacological and neurosurgical treatment in the management of prolactinomas. We recommend cabergoline (Cab) vs. bromocriptine (Br) as the firstchoice pharmacological treatment to be employed at the minimal effective dose capable of achieving the regression of the clinical picture. We suggest that medication and surgery are offered as suitable alternative first-line treatments to patients with non-invasive PRL-secreting adenoma, regardless of size. We suggest Br as an alternative drug in patients who are intolerant to Cab and are not candidates for surgery. We recommend pituitary tumor resection in patients 1) without any significant neuro-ophthalmologic improvement within two weeks from the start of Cab, 2) who are resistant or do not tolerate Cab or other dopamine-agonist drugs (DA), 3) who escape from previous efficacy of DA, and 4) who are unwilling to undergo a chronic DA treatment. We recommend that patients with progressive disease notwithstanding previous tumor resection and ongoing DA should be managed by a multidisciplinary team with specific expertise in pituitary diseases using a multimodal approach that includes repeated surgery, radiotherapy, DA, and possibly, the use of temozolomide. CONCLUSION: The present GL is directed to endocrinologists, neurosurgeons, and gynecologists working in hospitals, in territorial services or private practice, and to general practitioners and patients.

Endoscopic Endonasal Excision of a Cavernous Hemangioma of the Orbital Apex with Cryoprobe Assistance: Two-Dimensional Surgical Video.

Cavernous hemangiomas (CHs) represent the commonest benign orbital lesion in adults, accounting for nearly 6% of overall orbital tumors.1The most common presenting symptoms include unilateral visual deficits, diplopia, ocular muscle impairment, and nonpulsatile proptosis. CHs can be asymptomatic until they reach a considerable size, but when lodged deep in the orbital apex, even small masses may cause severe functional deficits.2 If found incidentally, a wait-and-scan policy is advised. Surgical treatment is indicated in patients with visual impairment or in cases of volumetric increase during the follow-up.3 Among the different surgical corridors to the orbital apex, in the last decade, the endoscopic-assisted approaches, both transpalpebral and endonasal, have emerged as minimally invasive and effective techniques in the skull base surgeon's armamentarium.4 If those lesions are located medially to the optic nerve, the endoscopic endonasal approaches (EEAs) offer several advantages compared with standard craniotomies or orbitotomies.5,6 A 45-year-old woman was admitted to our hospital with symptoms of progressive right visual impairment for 10 months, with radiologic finding of an encapsulated small roundish lesion at the right orbital apex. The mass was completely removed by means of EEA with intraoperative use of a dedicated cryoprobe (Video 1). Histopathologic examination confirmed the CH. At follow-up, the patient experienced complete resolution of her symptoms, with no residues or relapses on magnetic resonance imaging. This case sheds light on the advantages of EEA with the assistance of a cryoprobe, including optimal visualization of the target, lack of external incision, no brain retraction, and short hospital stays.

Endoscopic transventricular approach for the resection of a hemorrhagic cavernous malformation of the tectal plate: Operative video.

Background: Cavernomas of the third ventricle are rare entities that provide significant therapeutic challenges. Because of the better view of the surgical field and the possibility to achieve a gross total resection (GTR), microsurgical approaches are more commonly used to target the third ventricle. Endoscopic transventricular approaches (ETVA), on the other hand, are minimally invasive procedures that can afford a straight corridor trough the lesion, avoiding bigger craniotomies. Moreover, these approaches have shown lower infectious risks and shorter hospitalization times. Case Description: A 58-year-old female patient accessed the Emergency Department complaining of headache, vomiting, mental confusion, and syncopal episodes for the past 3 days. An urgent brain computed tomography scan revealed a hemorrhagic lesion of the third ventricle, conditioning triventricular hydrocephalus, so an external ventricular drainage (EVD) was placed in an emergency setting. An magnetic resonance imaging (MRI) showed a 10 mm diameter hemorrhagic cavernous malformation originating from the superior tectal plate. An ETVA was performed for the cavernoma resection, followed by an endoscopic third ventriculostomy. After proving shunt independence, the EVD was removed. No clinical nor radiological complications were assisted in the postoperative period, so the patient was discharged 7 days after. The histopathological examination was consistent with cavernous malformation. An immediate postoperative MRI showed GTR of the cavernoma with a little clot around the surgical cavity, which appeared completely reabsorbed 4 months later. Conclusion: ETVA provides a straight corridor to the third ventricle, excellent visualization of the relevant anatomical structures, safe resection of the lesion, and treatment of the concomitant hydrocephalus by ETV.

Orbital resection by intranasal technique (ORBIT): A new classification system for reporting endoscopically resectable primary benign orbital tumors.

BACKGROUND: The Cavernous Hemangioma Exclusively Endonasal Resection (CHEER) staging system has become the gold standard for outcomes reporting in endoscopic orbital surgery for orbital cavernous hemangiomas (OCHs). A recent systematic review demonstrated similar outcomes between OCHs and other primary benign orbital tumors (PBOTs). Therefore, we hypothesized that a simplified and more comprehensive classification system could be developed to predict surgical outcomes of other PBOTs. METHODS: Patient and tumor characteristics as well as surgical outcomes from 11 international centers were recorded. All tumors were retrospectively assigned an Orbital Resection by Intranasal Technique (ORBIT) class and stratified based on surgical approach as either exclusively endoscopic or combined (endoscopic and open). Outcomes based on approach were compared using chi-squared or Fisher's exact tests. The Cochrane-Armitage test for trend was used to analyze outcomes by class. RESULTS: Findings from 110 PBOTs from 110 patients (age 49.0 ± 15.0 years, 51.9% female) were included in the analysis. Higher ORBIT class was associated with a lower likelihood of gross total resection (GTR). GTR was more likely to be achieved when an exclusively endoscopic approach was utilized (p < 0.05). Tumors resected using a combined approach tended to be larger, to present with diplopia, and to have an immediate postoperative cranial nerve palsy (p < 0.05). CONCLUSION: Endoscopic treatment of PBOTs is an effective approach, with favorable short-term and long-term postoperative outcomes as well as low rate of adverse events. The ORBIT classification system is an anatomic-based framework that effectively facilitates high-quality outcomes reporting for all PBOTs.

COVID-19-associated Guillain-Barré syndrome in the early pandemic experience in Lombardia (Italy).

OBJECTIVE: To estimate the incidence and describe clinical characteristics and outcome of GBS in COVID-19 patients (COVID19-GBS) in one of the most hit regions during the first pandemic wave, Lombardia. METHODS: Adult patients admitted to 20 Neurological Units between 1/3-30/4/2020 with COVID19-GBS were included as part of a multi-center study organized by the Italian society of Hospital Neuroscience (SNO). RESULTS: Thirty-eight COVID19-GBS patients had a mean age of 60.7 years and male frequency of 86.8%. CSF albuminocytological dissociation was detected in 71.4%, and PCR for SARS-CoV-2 was negative in 19 tested patients. Based on neurophysiology, 81.8% of patients had a diagnosis of AIDP, 12.1% of AMSAN, and 6.1% of AMAN. The course was favorable in 76.3% of patients, stable in 10.5%, while 13.2% worsened, of which 3 died. The estimated occurrence rate in Lombardia ranges from 0.5 to 0.05 GBS cases per 1000 COVID-19 infections depending on whether you consider positive cases or estimated seropositive cases. When we compared GBS cases with the pre-pandemic period, we found a reduction of cases from 165 to 135 cases in the 2-month study period in Lombardia. CONCLUSIONS: We detected an increased incidence of GBS in COVID-19 patients which can reflect a higher risk of GBS in COVID-19 patients and a reduction of GBS events during the pandemic period possibly due to a lower spread of more common respiratory infectious diseases determined by an increased use of preventive measures.

Endoscopic endonasal approach for infradiaphragmatic craniopharyngiomas: a multicentric Italian study.

OBJECTIVE: Infradiaphragmatic craniopharyngiomas (ICs) represent a distinct subtype, harboring a sellar-suprasellar origin and generally growing in the extra-arachnoidal space contained by the diaphragma sellae. They have been considered ideal for surgical removal through the transsphenoidal approach since the 1960s. The authors present a multicentric national study, intending to selectively analyze IC behavior and the impact of the transsphenoidal endoscopic endonasal approach (EEA) on surgical outcomes. METHODS: Craniopharyngiomas that were intraoperatively recognized as infradiaphragmatic and removed with standard EEA between 2000 and 2021 at 6 Italian neurosurgical departments were included in the study. Clinical, radiological, and surgical findings and outcomes were evaluated and reviewed. RESULTS: In total, 84 patients were included, with 45.23% identified as pediatric cases and 39.28% as having recurrent tumors. The most common presenting symptoms were endocrine (75%), visual (59.52%), and hypothalamic (26.19%) disorders. ICs were classified as extending below (6 intrasellar and 41 occupying the suprasellar cistern) or above (26 obliterating the anterior recesses of the third ventricle and 11 extending up to the foramina of Monro) the chiasmatic cistern. Gross-total resection (GTR) was achieved in 54 cases (64.28%). Tumor extension above the chiasmatic cistern and calcifications were associated with lower likelihood of GTR. The cumulative rate of postoperative complications was 34.53%, with CSF leak being the most common (14.28%). Endocrine, visual, and hypothalamic functions deteriorated postoperatively in 41/78 patients (52.56%), 5/84 (5.95%), and 14/84 (16.67%), respectively. Twenty-eight patients (33.33%) had recurrence during follow-up (mean 63.51 months), with a mean 5-year progression-free survival (PFS) rate of 58%. PFS was greater in patients who achieved GTR than patients with other extent of resection. CONCLUSIONS: This is the largest series in the literature to describe ICs removed with standard EEA, without the need for additional bone and dural opening over the planum sphenoidale. EEA provides a direct route to ICs, the opportunity to manage lesions extending up to the third ventricle without breaching the diaphragma, and high rates of GTR and satisfactory clinical outcomes. Increased surgical complexity and morbidity should be expected in patients with extensive suprasellar extension and involvement of the surrounding vital neurovascular structures.

Comaneci-Assisted Coiling of Wide-Necked Intracranial Aneurysm: A Single-Center Preliminary Experience.

BACKGROUND: Wide-necked aneurysms remain challenging for both coiling and microsurgical clipping. They often require additional techniques to prevent coil prolapse into the parent artery, such as balloon- and stent-assisted coiling. Comaneci is an expandable and removable stent that acts as a bridging device and does not interfere with the blood flow of the parent artery. METHODS: We retrospectively reviewed our institutional radiological and clinical chart of patients treated for saccular intracranial aneurysm via endovascular Comaneci-assisted coiling. The aim of the study was to report our preliminary experience in Comaneci-assisted coiling of wide-necked intracranial aneurysms. RESULTS: We included 14 patients in the study. Of these, 11 had a ruptured intracranial aneurysm and were treated with Comaneci-assisted coiling. We registered five minor intraprocedural complications and two intraprocedural failures of the device. At one-year follow-up, a satisfying aneurysm occlusion was observed in 85% of the cases. CONCLUSIONS: Though long-term follow-up data and larger case series are needed, this preliminary study showed the feasibility of the Comaneci-assisted coiling method for both ruptured and unruptured wide-neck intracranial aneurysms, with similar occlusion rates as balloon-assisted coiling. However, we registered high incidence of thromboembolic complications; these were probably related to the lack of heparin administration. The main advantageous application of this technique is likely in cases of ruptured intracranial aneurysms, as there is no need for post-procedural antiplatelet therapy.

Quantitative Anatomic Comparison of Endoscopic Transnasal and Microsurgical Transcranial Approaches to the Anterior Cranial Fossa.

BACKGROUND: Several microsurgical transcranial approaches (MTAs) and endoscopic transnasal approaches (EEAs) to the anterior cranial fossa (ACF) have been described. OBJECTIVE: To provide a preclinical, quantitative, anatomic, comparative analysis of surgical approaches to the ACF. METHODS: Five alcohol-fixed specimens underwent high-resolution computed tomography. The following approaches were performed on each specimen: EEAs (transcribriform, transtuberculum, and transplanum), anterior MTAs (transfrontal sinus interhemispheric, frontobasal interhemispheric, and subfrontal with unilateral and bilateral frontal craniotomy), and anterolateral MTAs (supraorbital, minipterional, pterional, and frontotemporal orbitozygomatic approach). An optic neuronavigation system and dedicated software (ApproachViewer, part of GTx-Eyes II-UHN) were used to quantify the working volume of each approach and extrapolate the exposure of different ACF regions. Mixed linear models with random intercepts were used for statistical analyses. RESULTS: EEAs offer a large and direct route to the midline region of ACF, whose most anterior structures (ie, crista galli, cribriform plate, and ethmoidal roof) are also well exposed by anterior MTAs, whereas deeper ones (ie, planum sphenoidale and tuberculum sellae) are also well exposed by anterolateral MTAs. The orbital roof region is exposed by both anterolateral and lateral MTAs. The posterolateral region (ie, sphenoid wing and optic canal) is well exposed by anterolateral MTAs. CONCLUSION: Anterior and anterolateral MTAs play a pivotal role in the exposure of most anterior and posterolateral ACF regions, respectively, whereas midline regions are well exposed by EEAs. Furthermore, certain anterolateral approaches may be most useful when involvement of the optic canal and nerves involvement are suspected.

Endoscopic Endonasal Transethmoidal-Transsphenoidal Approach to a Cavernous Sinus Chondrosarcoma.

Objective We illustrate a cavernous sinus chondrosarcoma treated with an endoscopic endonasal transethmoidal-transsphenoidal approach. Design Case report of a 15-year-old girl with diplopia and esotropia due to complete abducens palsy. Preoperative images showed a right cavernous sinus lesion with multiple enhanced septa and intralesional calcified spots ( Fig. 1 ). Considering tumor location and the lateral dislocation of the carotid artery, an endoscopic endonasal approach was performed to relieve symptoms and to optimize the target geometry for adjuvant conformal radiotherapy. Setting The study was conducted at University of Insubria, Department of Neurosurgery, Varese, Italy. Participants Skull base team was participated in the study. Main Outcome Measures A transethmoidal-transsphenoidal approach was performed by using a four-hand technique. We used a route lateral to medial turbinate to access ethmoid and the sphenoid sinus. During the sphenoid phase, we exposed the medial wall of the cavernous sinus ( Fig. 2 ) and the lesion was then removed using curette. Skull base reconstruction was performed with fibrin glue and nasoseptal flap. Results No complications occurred after surgery, and the patient experienced a complete recovery of symptoms. A postoperative magnetic resonance imaging showed a small residual tumor inside the cavernous sinus ( Fig. 1 ). After percutaneous proton-bean therapy, patient experienced only temporary low-grade toxicity with local control within 2 years after treatment completion. Conclusion Endoscopic endonasal extended approach is a safe and well-tolerated procedure that is indicated in selected cases (intracavernous tumors, soft tumors not infiltrating the vessels and/or the nerves). A tailored approach according to tumor extension is crucial for the best access to the compartments involved. The link to the video can be found at: https://youtu.be/TsqXjqpuOws .

Posterior fossa syndrome in a population of children and young adults with medulloblastoma: a retrospective, multicenter Italian study on incidence and pathophysiology in a histologically homogeneous and consecutive series of 136 patients.

INTRODUCTION: Posterior fossa syndrome (PFS) is a set of debilitating complications that can occur after surgery for posterior fossa tumors. This study aimed to assess the preoperative radiological and surgical risk factors for the onset of PFS in a histologically homogeneous population of children with medulloblastoma and compare it to a similar population of young adults. METHODS: Included patients underwent posterior fossa surgery for medulloblastoma at 11 Italian neurosurgical wards (2003-2019) and were referred to Fondazione IRCCS Istituto Nazionale dei Tumori in Milan (INT) for postoperative treatments. We collected patients' pre- and post-operative clinical, surgical and radiological data from the INT charts. To compare the distribution of variables, we used the Mann-Whitney and Fisher tests for continuous and categorical variables, respectively. RESULTS: 136 patients (109 children and 27 young adults) were included in the study. Among children, 29 (27%) developed PFS, and all of them had tumors at midline site with invasion of the fourth ventricle. Radiological evidence of involvement of the right superior (39% versus 12%; p = 0.011) or middle cerebellar peduncles (52% versus 18%; p = 0.002) seemed more common in children who developed PFS. Young adults showed an expected lower incidence of PFS (4 out of 27; 15%), that may be due to anatomical, physiological and oncological elements. CONCLUSIONS: This study confirmed some factors known to be associated with PFS onset and shed light on other debated issues. Our findings enhance an already hypothesized role of cerebellar language lateralization. The analysis of a population of young adults may shed more light on the often-neglected existence of PFS in non-pediatric patients.

Frameless neuronavigation-assisted brain biopsy with electromagnetic tracking: how I do it?

BACKGROUND: In recent years, thanks to several technological innovations, stereotactic cerebral biopsies have evolved from frame-based to frameless neuronavigation-assisted techniques. METHODS: The authors provide herein a detailed step-by-step description of the technique, shedding light on surgical tips and how to avoid complications. The practical application of the technique is demonstrated with a high-quality video. CONCLUSION: The neuronavigation-assisted brain biopsy with electromagnetic tracking is a "true frameless" procedure. It represents a simple, safe, and effective innovation for frameless biopsy of cerebral lesions. This technique is time efficient, offering a high degree of accuracy required for the establishment of a definitive diagnosis, enabling optimal further treatment, and thus improving patient outcome.