Developing Deep Learning-Based Cerebral Ventricle Auto-Segmentation System and Clinical Application for the Evaluation of Ventriculomegaly.

Objective: Current methods for evaluating ventriculomegaly, particularly Evans' Index (EI), fail to accurately assess three-dimensional ventricular changes. We developed and validated an automated multiclass segmentation system for precise volumetric assessment, simultaneously segmenting 5 anatomical classes (ventricles, parenchyma, skull, skin, and hemorrhage) to support future augmented reality-guided external ventricular drainage (EVD) systems.

Methods: Using the nnUNet architecture, we trained our model on 288 brain computed tomography scans with diverse pathological conditions and validated it using internal (n = 10), external (n = 43), and public (n = 192) datasets.

Exploratory profiling of metabolites in cerebrospinal fluid using a commercially available targeted LC-MS based metabolomics kit to discriminate leptomeningeal metastasis.

Background: Leptomeningeal metastasis (LM) is a devastating complication of cancer that is difficult to treat. Thus, early diagnosis is essential for LM patients. However, cerebrospinal fluid (CSF) cytology has low sensitivity, and imaging approaches are ineffective.

Envisioning the Future of the Neurosurgical Operating Room with the Concept of the Medical Metaverse.

The medical metaverse can be defined as a virtual spatiotemporal framework wherein higher-dimensional medical information is generated, exchanged, and utilized through communication among medical personnel or patients. This occurs through the integration of cutting-edge technologies such as augmented reality (AR), virtual reality (VR), artificial intelligence (AI), big data, cloud computing, and others. We can envision a future neurosurgical operating room that utilizes such medical metaverse concept such as shared extended reality (AR/VR) of surgical field, AI-powered intraoperative neurophysiological monitoring, and real-time intraoperative tissue diagnosis.

Extracellular Vesicles from Cerebrospinal Fluid of Leptomeningeal Metastasis Patients Deliver MiR-21 and Induce Methotrexate Resistance in Lung Cancer Cells.

Leptomeningeal metastasis (LM) is a common and fatal complication of advanced non-small cell lung cancer (NSCLC) caused by the spread of malignant cells to the leptomeninges and cerebrospinal fluid (CSF). While intra-CSF methotrexate (MTX) chemotherapy can improve prognosis, eventual MTX resistance deters continued chemotherapy. Recent studies have shown that increased miRNA-21 (miR-21) expression in the CSF of patients with LM after intraventricular MTX-chemotherapy is associated with poor overall survival; however, the molecular mechanisms underlying this resistance are poorly understood.

Disseminating Necrotizing Leukoencephalopathy Associated With Intra-CSF Methotrexate Chemotherapy: A Retrospective Observational Study.

Background And Objectives: Leptomeningeal metastases (LMs) are neoplasms that proliferate to membranes lining the brain and spinal cord. Intra-CSF methotrexate (MTX) chemotherapy is a prevalent treatment option. However, resultant long-term neurotoxicity can lead to irreversible disseminated necrotizing leukoencephalopathy (DNL).

A 3-month survival model after Gamma Knife surgery in patients with brain metastasis from lung cancer with Karnofsky performance status ≤ 70.

Gamma Knife surgery (GKS) for brain metastasis (BM) has been generally advocated for patients with a Karnofsky performance status (KPS) scale of ≥ 70. However, some patients with a poor KPS scale of < 70 are recoverable after GKS and show durable survival. A purpose of this study is to devise a 3-month survival prediction model to screen patients with BM with a KPS of ≤ 70 in whom GKS is needed.

Validation of real-time inside-out tracking and depth realization technologies for augmented reality-based neuronavigation.

Purpose: Concomitant with the significant advances in computing technology, the utilization of augmented reality-based navigation in clinical applications is being actively researched. In this light, we developed novel object tracking and depth realization technologies to apply augmented reality-based neuronavigation to brain surgery.

Methods: We developed real-time inside-out tracking based on visual inertial odometry and a visual inertial simultaneous localization and mapping algorithm.

Changes of Resection Goal After Using 3-Dimensional Printing Brain Tumor Model for Presurgical Planning.

Background: Conventional 2-Dimensional magnetic resonance imaging-based neuronavigation systems can improve the maximal safe resection in brain tumor surgery but can be unintuitive. A 3-Dimensional (3D)-printed brain tumor model allows for a more intuitive and stereoscopic understanding of brain tumors and adjacent neurovascular structures. This study aimed to identify the clinical efficacy of a 3D-printed brain tumor model in presurgical planning by focusing on differences in the extent of resection (EOR).

Functional Magnetic Resonance Imaging and Diffusion Tensor Imaging for Language Mapping in Brain Tumor Surgery: Validation With Direct Cortical Stimulation and Cortico-Cortical Evoked Potential.

Objective: Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging-derived tractography (DTI-t) contribute to the localization of language areas, but their accuracy remains controversial. This study aimed to investigate the diagnostic performance of preoperative fMRI and DTI-t obtained with a simultaneous multi-slice technique using intraoperative direct cortical stimulation (DCS) or corticocortical evoked potential (CCEP) as reference standards.

Materials And Methods: This prospective study included 26 patients (23-74 years; male:female, 13:13) with tumors in the vicinity of Broca's area who underwent preoperative fMRI and DTI-t.

The Korean Society for Neuro-Oncology (KSNO) Guideline for the Management of Brain Tumor Patients During the Crisis Period: A Consensus Survey About Specific Clinical Scenarios (Version 2023.1).

Background: During the coronavirus disease 2019 (COVID-19) pandemic, there was a shortage of medical resources and the need for proper treatment guidelines for brain tumor patients became more pressing. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has undertaken efforts to develop a guideline that is tailored to the domestic situation and that can be used in similar crisis situations in the future. As part II of the guideline, this consensus survey is to suggest management options in specific clinical scenarios during the crisis period.

Optimal mask fixation method for frameless radiosurgery with Leksell Gamma Knife Icon.

The Leksell Gamma Knife (LGK) Icon is used for mask-based and frame-based fixation. The mask fixation provides a noninvasive method. However, an optimal mask fixation method is yet to be established.

Avoiding a Collision in Gamma Knife Radiosurgery : A Modified Mask Fixation Method.

Objective: The latest version of the Leksell Gamma Knife IconTM allows for mask- and frame-based fixation. Although mask fixation provides fractionated treatment and immobilization using a noninvasive method, it is not free from collision. The authors investigated the collision problem with a modified mask fixation method.

Development of 3-dimensional printed simulation surgical training models for endoscopic endonasal and transorbital surgery.

Background: Endoscopic skull base surgery (ESBS) is complex, requiring methodical and unremitting surgical training. Herein, we describe the development and evaluation of a novel three-dimensional (3D) printed simulation model for ESBS. We further validate the efficacy of this model as educational support in neurosurgical training.

Navigation of frameless fixation for gamma knife radiosurgery using fixed augmented reality.

Augmented reality (AR) offers a new medical treatment approach. We aimed to evaluate frameless (mask) fixation navigation using a 3D-printed patient model with fixed-AR technology for gamma knife radiosurgery (GKRS). Fixed-AR navigation was developed using the inside-out method with visual inertial odometry algorithms, and the flexible Quick Response marker was created for object-feature recognition.

Histopathological predictors of progression-free survival in atypical meningioma: a single-center retrospective cohort and meta-analysis.

To determine the prognostic significance of histopathological features included in the diagnostic criteria of atypical meningioma for progression-free survival (PFS). We performed a retrospective cohort study and meta-analysis. Brain invasion, mitotic index, spontaneous necrosis, sheeting, prominent nucleoli, high cellularity, and small cells were the histopathological features of interest.

Development of an inside-out augmented reality technique for neurosurgical navigation.

Objective: With the advancement of 3D modeling techniques and visualization devices, augmented reality (AR)-based navigation (AR navigation) is being developed actively. The authors developed a pilot model of their newly developed inside-out tracking AR navigation system.

Methods: The inside-out AR navigation technique was developed based on the visual inertial odometry (VIO) algorithm.

Outcomes of the endoscopic endonasal approach for tumors in the third ventricle or invading the third ventricle.

We aimed to retrospectively analyze the surgical and clinical outcomes of the endoscopic endonasal approach (EEA) for tumors in the third ventricle or invading the third ventricle. In total, 82 patients who had undergone surgical treatment using the EEA for tumors involving the third ventricle were enrolled in this study. This cohort study comprised 46 male and 36 female patients.

Multi-Layer Onlay Graft Using Hydroxyapatite Cement Placement without Cerebrospinal Fluid Diversion for Endoscopic Skull Base Reconstruction.

Objective: The skull base reconstruction step, which prevents cerebrospinal fluid (CSF) leakage, is one of the most challenging steps in endoscopic skull base surgery (ESS). The purpose of this study was to assess the outcomes and complications of a reconstruction technique for immediate CSF leakage repair using multiple onlay grafts following ESS.

Methods: A total of 230 consecutive patients who underwent skull base reconstruction using multiple onlay grafts with fibrin sealant patch (FSP), hydroxyapatite cement (HAC), and pedicled nasoseptal flap (PNF) for high-flow CSF leakage following ESS at three institutions were enrolled.

The Korean Society for Neuro-Oncology (KSNO) Guideline for Antiepileptic Drug Usage of Brain Tumor: Version 2021.1.

Background: To date, there has been no practical guidelines for the prescription of antiepileptic drugs (AEDs) in brain tumor patients in Korea. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for AED usage in brain tumors since 2019.

Methods: The Working Group was composed of 27 multidisciplinary medical experts in Korea.

The Korean Society for Neuro-Oncology (KSNO) Guideline for Adult Diffuse Midline Glioma: Version 2021.1.

Background: There have been no guidelines for the management of adult patients with diffuse midline glioma (DMG), H3K27M-mutant in Korea since the 2016 revised WHO classification newly defined this disease entity. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for DMG since 2019.

Methods: The Working Group was composed of 27 multidisciplinary medical experts in Korea.

Clinical application of patient-specific 3D printing brain tumor model production system for neurosurgery.

The usefulness of 3-dimensional (3D)-printed disease models has been recognized in various medical fields. This study aims to introduce a production platform for patient-specific 3D-printed brain tumor model in clinical practice and evaluate its effectiveness. A full-cycle platform was created for the clinical application of a 3D-printed brain tumor model (3D-printed model) production system.

Adjuvant radiotherapy versus observation following gross total resection for atypical meningioma: a systematic review and meta-analysis.

Background: The impact of adjuvant radiotherapy (RT) on atypical meningioma (AM) underwent a gross total resection (GTR) remains unclear, showing conflicting results from various studies. The objective of this study was to perform an updated meta-analysis for observational studies to determine the effect of adjuvant RT after GTR on local recurrence and survival outcomes compared to observation after GTR.

Methods: PubMed, Embase, and Web of Science were searched to identify comparative studies that reported outcomes of adjuvant RT versus observation for AM patients after GTR.