Olfactory groove meningiomas: supraorbital keyhole versus orbitofrontal, frontotemporal, or bifrontal approaches.

Objective: Olfactory groove meningiomas (OGMs) often require surgical removal. The introduction of recent keyhole approaches raises the question of whether these tumors may be better treated through a smaller cranial opening. One such approach, the supraorbital keyhole craniotomy, has never been compared with more traditional open transcranial approaches with regard to outcome.

Outcomes Following Early Postoperative Adjuvant Radiosurgery for Brain Metastases.

Importance: Adjuvant stereotactic radiosurgery (SRS) enhances the local control of resected brain metastases (BrM). However, the risks of local failure (LF) and potential for posttreatment adverse radiation effects (PTRE) after early postoperative adjuvant SRS have not yet been established.

Objective: To evaluate whether adjuvant SRS delivered within a median of 14 days after surgery is associated with improved LF without a concomitant increase in PTRE.

Treatment and outcomes of IDH1-mutant gliomas in elderly patients.

Objective: Isocitrate dehydrogenase (IDH) mutations in both high- and low-grade gliomas are associated with an increase in survival compared with IDH-wild-type (IDHwt) tumors. A rare and understudied population is elderly individuals, ≥ 65 years of age, who have IDH1-R132H-mutant (IDHmt) gliomas. The objective of this paper was to characterize the institutions' experience with IDHmt gliomas in a patient population ≥ 65 years of age over the last 10 years.

The Endoscopic Lateral Transorbital Approach for the Removal of Select Sphenoid Wing and Middle Fossa Meningiomas. Surgical Technique and Short-Term Outcomes.

Background And Objective: The endoscopic lateral transorbital approach (eLTOA) is a relatively new approach to the skull base that has only recently been applied in vivo in the management of complex skull base pathology. Most meningiomas removed with this approach have been in the spheno-orbital location. We present a series of select purely sphenoid wing and middle fossa meningiomas removed through eLTOA.

Lateral Transorbital Endoscope-Assisted Approach to the Cavernous Sinus.

Background And Objectives: Surgical access to the cavernous sinus (CS) poses a unique challenge to the neurosurgeon given the concentration of delicate structures in the confines of a very small anatomic space. The lateral transorbital approach (LTOA) is a minimally invasive, keyhole approach that can provide direct access to the lateral CS.

Methods: A retrospective review of CS lesions treated by a LTOA at a single institution was performed between 2020 and 2023.

Endonasal, supraorbital, and transorbital approaches: minimal access endoscope-assisted surgical approaches for meningiomas in the anterior and middle cranial fossae.

Objective: Minimally invasive endoscope-assisted approaches to the anterior skull base offer an alternative to traditional open craniotomies. Given the restrictive operative corridor, appropriate case selection is critical for success. In this paper, the authors present the results of three different minimal access approaches to meningiomas of the anterior and middle fossae and examine the differences in the target areas considered appropriate for each approach, as well as the outcomes, to determine whether the surgical goals were achieved.

Safety and efficacy of Cesium-131 brachytherapy for brain tumors.

Background: The introduction of Cesium-131 (Cs-131) as a radiation source has led to a resurgence of brachytherapy for central nervous system (CNS) tumors. The aim of this study was to evaluate the safety and efficacy of the largest cohort of Cs-131 patients to-date.

Methods: A retrospective review of all CNS tumors treated with resection and adjuvant Cs-131 brachytherapy at New York-Presbyterian/Weill Cornell from 2010 to 2021 was performed.

Brachytherapy for central nervous system tumors.

Radiation is a mainstay of treatment for central nervous system (CNS) tumors. Brachytherapy involves the placement of a localized/interstitial radiation source into a tumor or resection bed and has distinct advantages that can make it an attractive form of radiation when used in the appropriate setting. However, the data supporting use of brachytherapy is clouded by variability in radiation sources, techniques, delivered doses, and trial designs.

Perspectives on Microglia-Based Immune Therapies Against Glioblastoma.

Glioblastoma (GBM) is the most aggressive primary tumor of the central nervous system. Despite aggressive multimodal therapy, it has a dismal prognosis. Over the last 20 years, the approach to GBM research and therapy has involved viewing the pathologic condition as a complex organ system with multiple nonneoplastic cells supporting tumor growth directly or through enhancement of the tumor microenvironment.

The Benedict Arnold of the Central Nervous System Tumor Microenvironment? The Role of Microglia/Macrophages in Glioma.

The glioma microenvironment is heavily infiltrated by non-neoplastic myeloid cells, including bone marrow-derived macrophages and central nervous system-resident microglia. As opposed to executing the antitumor functions of immune surveillance, antigen presentation, and phagocytosis, these tumor-associated myeloid cells are co-opted to promote an immunosuppressive milieu and support tumor invasion and angiogenesis. This review explores evolving evidence and the research paradigms used to determine the interplay of tumor genetics, immune cell composition, and immune function in gliomas.

Cerebrospinal fluid diversion for leptomeningeal metastasis: palliative, procedural and oncologic outcomes.

Background: Leptomeningeal metastasis (LM) occurs in 3-5% of patients with solid metastatic tumors and often portends a severe prognosis including symptomatic hydrocephalus and intracranial hypertension. Cerebrospinal fluid (CSF) shunting can provide symptomatic relief in this patient subset; however, few studies have examined the role of shunting in the palliation, prognosis and overall oncologic care of these patients.

Objective: To identify and evaluate risk factors associated with prognosis after CSF diversion and assess surgical, symptomatic and oncologic outcomes in this population.

Durable 5-year local control for resected brain metastases with early adjuvant SRS: the effect of timing on intended-field control.

Background: Adjuvant stereotactic radiosurgery (SRS) improves the local control of resected brain metastases (BrM). However, the dependency of long-term outcomes on SRS timing relative to surgery remains unclear.

Methods: Retrospective analysis of patients treated with metastasectomy-plus-adjuvant SRS at Memorial Sloan Kettering Cancer Center (MSK) between 2013 and 2016 was conducted.

Evaluation of a patient-specific algorithm for predicting distribution for convection-enhanced drug delivery into the brainstem of patients with diffuse intrinsic pontine glioma.

Objective: With increasing use of convection-enhanced delivery (CED) of drugs, the need for software that can predict infusion distribution has grown. In the context of a phase I clinical trial for pediatric diffuse intrinsic pontine glioma (DIPG), CED was used to administer an anti-B7H3 radiolabeled monoclonal antibody, iodine-124-labeled omburtamab. In this study, the authors retrospectively evaluated a software algorithm (iPlan Flow) for the estimation of infusate distribution based on the planned catheter trajectory, infusion parameters, and patient-specific MRI.

Melanoma brain metastasis presentation, treatment, and outcomes in the age of targeted and immunotherapies.

Background: Historically, the prognosis for patients who have melanoma brain metastasis (MBM) has been dismal. However, breakthroughs in targeted and immunotherapies have improved long-term survival in those with advanced melanoma. Therefore, MBM presentation, prognosis, and the use of multimodality central nervous system (CNS)-directed treatment were reassessed.

Beyond guidelines: analysis of current practice patterns of AANS/CNS tumor neurosurgeons.

Introduction: Evidence-based medicine guidelines are increasingly published and sanctioned by organized neurosurgery. However, implementation, interpretation, and use of clinical guidelines may vary substantially on a regional, national and international basis. Survey research can help bridge the gap by providing a snapshot of neurosurgeon attitudes, knowledge, and practices.

Repeat convection-enhanced delivery for diffuse intrinsic pontine glioma.

Objective: While the safety and efficacy of convection-enhanced delivery (CED) have been studied in patients receiving single-dose drug infusions, agents for oncological therapy may require repeated or chronic infusions to maintain therapeutic drug concentrations. Repeat and chronic CED infusions have rarely been described for oncological purposes. Currently available CED devices are not approved for extended indwelling use, and the only potential at this time is for sequential treatments through multiple procedures.

Use of the train-of-five bipolar technique to provide reliable, spatially accurate motor cortex identification in asleep patients.

Objective: Intraoperative cortical and subcortical mapping techniques have become integral for achieving a maximal safe resection of tumors that are in or near regions of eloquent brain. The recent literature has demonstrated successful motor/language mapping with lower rates of stimulation-induced seizures when using monopolar high-frequency stimulation compared to traditional low-frequency bipolar stimulation mapping. However, monopolar stimulation carries with it disadvantages that include more radiant spread of electrical stimulation and a theoretically higher potential for tissue damage.

Deformational changes after convection-enhanced delivery in the pediatric brainstem.

Objective: In the brainstem, there are concerns regarding volumetric alterations following convection-enhanced delivery (CED). The relationship between distribution volume and infusion volume is predictably greater than one. Whether this translates into deformational changes and influences clinical management is unknown.

Microvessel occlusions alter amyloid-beta plaque morphology in a mouse model of Alzheimer's disease.

Vascular dysfunction is correlated to the incidence and severity of Alzheimer's disease. In a mouse model of Alzheimer's disease (APP/PS1) using in vivo, time-lapse, multiphoton microscopy, we found that occlusions of the microvasculature alter amyloid-beta (Aβ) plaques. We used several models of vascular injury that varied in severity.

Spontaneous regression of a clival chordoma. Case report.

In this case report, we present a rare and previously unreported case of spontaneous regression of a histologically consistent clival chordoma. At the time of diagnosis, imaging demonstrated a T2 hyperintense and T1 isointense midline skull base mass, centered in the nasopharynx, with scalloping of the ventral clivus consistent with a chordoma measuring 3.1 × 1.

Tubular brain tumor biopsy improves diagnostic yield for subcortical lesions.

Purpose: Molecular data has become an essential part of the updated World Health Organization (WHO) grading of central nervous system tumors. However, stereotactic needle biopsies provide only small volume specimens and limit the extent of histologic and molecular testing that can be performed. We assessed the use of a tubular retractor-based minimally invasive biopsy technique to provide improved tissue yield and diagnostic data compared to needle biopsy.

Advances in Glioblastoma Operative Techniques.

Numerous studies have demonstrated the importance of gross total resection in improving patient survival in glioblastoma (GBM). Advances in surgical tools and techniques such as intra-operative imaging, fluorescent agents, and functional imaging sequences are allowing for better identification of tumor borders and vital eloquent cortex in order to safely achieve higher rates of complete resections. Furthermore, due to the limits of surgical resection alone, new minimally invasive techniques for treatment of GBM are under development.