DNA methylation analysis reveals an epigenetic signature distinctive of high-grade oligodendroglioma.

IDH-mutant gliomas represent a subtype of diffuse gliomas that primarily affect patients in early to mid-adolescence. These tumors are classified into three distinct CNS WHO grades of malignancy. Accurate grading is essential for selecting an appropriate treatment maximizing anti-tumor efficacy while minimizing adverse effects.

Toward Noninvasive High-Resolution In Vivo pH Mapping in Brain Tumors by P-Informed deepCEST MRI.

The intracellular pH (pH) is critical for understanding various pathologies, including brain tumors. While conventional pH measurement through P-MRS suffers from low spatial resolution and long scan times, H-based APT-CEST imaging offers higher resolution with shorter scan times. This study aims to directly predict P-pH maps from CEST data by using a fully connected neuronal network.

Pathological tissue changes in brain tumors affect the pH-sensitivity of the T1-corrected apparent exchange dependent relaxation (AREX) of the amide protons.

Measuring the intracellular pH (pHi) is of interest for brain tumor diagnostics. Common metrics of CEST imaging like the amide proton transfer-weighted (APTw) MTR are pHi sensitive and allow differentiating malignant tumor from healthy tissue. Yet, the image contrast also depends on additional magnetization transfer effects and T1.

Gliomatosis cerebri (GC) growth pattern: A single-center analysis of clinical, histological, and molecular characteristics of GC and non-GC glioblastoma.

Background: The biological understanding of glioblastoma (GB) with gliomatosis cerebri (GC) pattern is poor due to the absence of GC-specific studies. Here, we aimed to identify molecular or clinical parameters that drive GC growth.

Methods: From our methylome database of IDH (isocitrate dehydrogenase)-wildtype GB, we identified 158 non-GC and 65 GC cases.

Longitudinal study on MRI and neuropathological findings: Neither DSC-perfusion derived rCBVmax nor vessel densities correlate between newly diagnosed and progressive glioblastoma.

Introduction: When evaluating MRIs for glioblastoma progression, previous scans are usually included into the review. Nowadays dynamic susceptibility contrast (DSC)-perfusion is an essential component in MR-diagnostics of gliomas, since the extent of hyperperfusion upon first diagnosis correlates with gene expression and survival. We aimed to investigate if this initial perfusion signature also characterizes the glioblastoma at time of progression.

Topographic Mapping of Isolated Thalamic Infarcts Using Vascular and Novel Probabilistic Functional Thalamic Landmarks.

Purpose: We aimed to re-evaluate the relationship between thalamic infarct (TI) localization and clinical symptoms using a vascular (VTM) and a novel functional territorial thalamic map (FTM).

Methods: Magnetic resonance imaging (MRI) and clinical data of 65 patients with isolated TI were evaluated (female n = 23, male n = 42, right n = 23, left n = 42). A VTM depicted the known seven thalamic vascular territories (VT: inferolateral, anterolateral, inferomedial, posterior, central, anteromedian, posterolateral).

Qualitative and quantitative detectability of hypertrophic olivary degeneration in T2, FLAIR, PD, and DTI: A prospective MRI study.

Purpose: Hypertrophic olivary degeneration (HOD) is a pathology of the inferior olivary nucleus (ION) that occurs after injuries to the Guillain-Mollaret triangle (GMT). Lacking a diagnostic gold standard, diagnosis is usually based on T2 or FLAIR imaging and expert rating. To facilitate precise HOD diagnosis in future studies, we assessed the reliability of this rater-based approach and explored alternative, quantitative analysis.

Static FET PET radiomics for the differentiation of treatment-related changes from glioma progression.

Purpose: To investigate the potential of radiomics applied to static clinical PET data using the tracer O-(2-[F]fluoroethyl)-L-tyrosine (FET) to differentiate treatment-related changes (TRC) from tumor progression (TP) in patients with gliomas.

Patients And Methods: One hundred fifty-one (151) patients with histologically confirmed gliomas and post-therapeutic progressive MRI findings according to the response assessment in neuro-oncology criteria underwent a dynamic amino acid PET scan using the tracer O-(2-[F]fluoroethyl)-L-tyrosine (FET). Thereof, 124 patients were investigated on a stand-alone PET scanner (data used for model development and validation), and 27 patients on a hybrid PET/MRI scanner (data used for model testing).

The Acute Superficial Siderosis Syndrome - Clinical Entity, Imaging Findings, and Histopathology.

Superficial siderosis is a consequence of repetitive bleeding into the subarachnoid space, leading to toxic iron and hemosiderin deposits on the surface of the brain and spine. The clinical and radiological phenotypes of superficial siderosis are known to manifest over long time intervals. In contrast, this study defines the "acute superficial siderosis syndrome" and illustrates typical imaging and histopathological findings of this entity.

Immune Checkpoint Inhibitor-Induced Cerebral Pseudoprogression: Patterns and Categorization.

Background: The inclusion of immune checkpoint inhibitors (ICIs) in therapeutic algorithms has led to significant survival benefits in patients with various metastatic cancers. Concurrently, an increasing number of neurological immune related adverse events (IRAE) has been observed. In this retrospective analysis, we examine the ICI-induced incidence of cerebral pseudoprogression and propose a classification system.

Multicenter Prospective Analysis of Hypertrophic Olivary Degeneration Following Infratentorial Stroke (HOD-IS): Evaluation of Disease Epidemiology, Clinical Presentation, and MR-Imaging Aspects.

Ischemic and hemorrhagic strokes in the brainstem and cerebellum with injury to the functional loop of the Guillain-Mollaret triangle (GMT) can trigger a series of events that result in secondary trans-synaptic neurodegeneration of the inferior olivary nucleus. In an unknown percentage of patients, this leads to a condition called hypertrophic olivary degeneration (HOD). Characteristic clinical symptoms of HOD progress slowly over months and consist of a rhythmic palatal tremor, vertical pendular nystagmus, and Holmes tremor of the upper limbs.

A 25-year retrospective, single center analysis of 343 WHO grade II/III glioma patients: implications for grading and temozolomide therapy.

Purpose: Classification and treatment of WHO grade II/III gliomas have dramatically changed. Implementing molecular markers into the WHO classification raised discussions about the significance of grading and clinical trials showed overall survival (OS) benefits for combined radiochemotherapy. As molecularly stratified treatment data outside clinical trials are scarce, we conducted this retrospective study.

Gliomatosis Cerebri Growth Pattern: Association of Differential First-Line Treatment with Overall Survival in WHO Grade II and III Gliomas.

Introduction: Gliomatosis cerebri (GC) is defined by diffuse, widespread glial tumor growth affecting three or more cerebral lobes. Previous studies in gliomas found no distinct histological or molecular GC subtype, yet the presence of GC is associated with worse median overall survival (OS). Here, we explored whether differing therapeutic strategies in first-line treatment could account for this.

A Paravermal Trans-Cerebellar Approach to the Posterior Fossa Tumor Causes Hypertrophic Olivary Degeneration by Dentate Nucleus Injury.

In brain tumor surgery, injury to cerebellar connectivity pathways can induce a neurodegenerative disease called hypertrophic olivary degeneration (HOD), along with a disabling clinical syndrome. In children, cerebellar mutism syndrome (CMS) is another consequence of damage to cerebello-thalamo-cortical networks. The goal of this study was to compare paravermal trans-cerebellar to other more midline or lateral operative approaches in their risk of causing HOD on MR-imaging and CMS.

Sequential implementation of DSC-MR perfusion and dynamic [F]FET PET allows efficient differentiation of glioma progression from treatment-related changes.

Purpose: Perfusion-weighted MRI (PWI) and O-(2-[F]fluoroethyl-)-l-tyrosine ([F]FET) PET are both applied to discriminate tumor progression (TP) from treatment-related changes (TRC) in patients with suspected recurrent glioma. While the combination of both methods has been reported to improve the diagnostic accuracy, the performance of a sequential implementation has not been further investigated. Therefore, we retrospectively analyzed the diagnostic value of consecutive PWI and [F]FET PET.

Regorafenib CSF Penetration, Efficacy, and MRI Patterns in Recurrent Malignant Glioma Patients.

(1) Background: The phase 2 Regorafenib in Relapsed Glioblastoma (REGOMA) trial indicated a survival benefit for patients with first recurrence of a glioblastoma when treated with the multikinase inhibitor regorafenib (REG) instead of lomustine. The aim of this retrospective study was to investigate REG penetration to cerebrospinal fluid (CSF), treatment efficacy, and effects on magnetic resonance imaging (MRI) in patients with recurrent high-grade gliomas. (2) Methods: Patients were characterized by histology, adverse events, steroid treatment, overall survival (OS), and MRI growth pattern.

Adrenal Insufficiency in Patients with Corticosteroid-Refractory Cerebral Radiation Necrosis Treated with Bevacizumab.

Cerebral radiation necrosis is a common complication of the radiotherapy of brain tumours that can cause significant mortality. Corticosteroids are the standard of care, but their efficacy is limited and the consequences of long-term steroid therapy are problematic, including the risk of adrenal insufficiency (AI). Off-label treatment with the vascular endothelial growth factor A antibody bevacizumab is highly effective in steroid-resistant radiation necrosis.

Longitudinal, leakage corrected and uncorrected rCBV during the first-line treatment of glioblastoma: a prospective study.

Purpose: Dynamic susceptibility contrast (DSC) MR-perfusion is becoming a standard of care for the monitoring of glioblastoma. Yet, technical standards are lacking and measurements without leakage correction are still common. Also, data on leakage corrected measurements during stable disease is scarce.

Early diagnosis in a case of atypically located germinoma: H-MR-spectroscopy as a decision tool.

CNS germinoma is a malignant germ cell tumor with a high potential for curative treatment. In MRI it mainly appears as contrast enhancing mass in the midline structures of the brain but it can also occur atypically located in the basal ganglia. We present the case of a 21-year-old patient suffering from psychiatric symptoms and a mild, right-sided hemiparesis.

Myoinositol as a Biomarker in Recurrent Glioblastoma Treated with Bevacizumab: A 1H-Magnetic Resonance Spectroscopy Study.

Background: Antiangiogenic treatment of glioblastomas with Bevacizumab lacks predictive markers. Myoinositol (MI) is an organic osmolyte, with intracellular concentration changes depending on the extracellular osmolality. Since Bevacizumab markedly reduces tumor edema and influences the tumor microenvironment, we investigated whether the MI concentration in the tumor changes during therapy.