Differentiating Glioma Recurrence and Pseudoprogression by APTw CEST MRI.

Objectives: Recurrent glioma is highly treatment resistant due to its metabolic, cellular, and molecular heterogeneity and invasiveness. Tumor monitoring by conventional MRI has shortcomings to assess these key glioma characteristics. Recent studies introduced chemical exchange saturation transfer for metabolic imaging in oncology and assessed its diagnostic value for newly diagnosed glioma.

Hyperperfusion and blood-brain barrier disruption beyond the diffusion-restricted infarct one day after successful mechanical thrombectomy.

Background And Purpose: Patterns of the cerebral microcirculatory response with changes in the blood brain barrier and perfusion in patients with stroke and a large vessel occlusion are still unclear. We combined dynamic contrast enhancement (DCE) permeability and DSC perfusion MRI to detect such patterns beyond the borders of the diffusion-restricted infarct core after successful recanalization.

Materials And Methods: Combined DCE permeability and DSC perfusion MRI were performed prospectively in patients within 24h after successful mechanical recanalization of acute middle cerebral artery occlusion.

Epineural Scarring Visualization and Noninvasive Quantification of a Severe Posttraumatic Complication: An Experimental Magnetic Resonance Neurography Study.

Aim: Peripheral nerve scarring is a severe yet common complication following nerve injury or surgery that can lead to impaired nerve function, including chronic pain and sensory or motor deficits. In this study, we aimed to establish high-resolution magnetic resonance neurography (MRN) to accurately visualize and monitor de novo-formed epineural fibrotic adhesions (EFAs) of the sciatic nerve in a rat nerve injury model.

Methods: Employing an established model to induce overshooting EFA, the study included 3 experimental groups of animals (n = 6 each): a positive control group (PC), an intervention group (IG), and a sham group.

T2-relaxometry in a large cohort of hereditary transthyretin amyloidosis with polyneuropathy.

Background: Previously, T2-relaxation time (T2) and proton spin density (ρ) detected nerve injury in a small group of ATTRv amyloidosis. Here, we aim to quantify peripheral nerve impairment in a large cohort of symptomatic and asymptomatic ATTRv amyloidosis and correlate T2-relaxometry markers with clinical parameters and nerve conduction studies (NCS).

Methods: Eighty participants with pathologic variants of the gene () and 40 controls prospectively underwent magnetic resonance neurography.

Automated peripheral nerve segmentation for MR-neurography.

Background: Magnetic resonance neurography (MRN) is increasingly used as a diagnostic tool for peripheral neuropathies. Quantitative measures enhance MRN interpretation but require nerve segmentation which is time-consuming and error-prone and has not become clinical routine. In this study, we applied neural networks for the automated segmentation of peripheral nerves.

Assessment of Tumor Cell Invasion and Radiotherapy Response in Experimental Glioma by Magnetic Resonance Elastography.

Background: Gliomas are highly invasive brain neoplasms. MRI is the most important tool to diagnose and monitor glioma but has shortcomings. In particular, the assessment of tumor cell invasion is insufficient.

Evolution of peripheral nerve changes in early multiple sclerosis-a longitudinal MR neurography study.

Objectives: Multiple sclerosis (MS) is a demyelinating disorder of the central nervous system. Increasing evidence indicates additional peripheral nerve involvement in early and chronic disease stages. To investigate the evolution of peripheral nerve changes in patients first diagnosed with MS using quantitative MR neurography.

Diffusion tensor imaging in anisotropic tissues: application of reduced gradient vector schemes in peripheral nerves.

Background: In contrast to the brain, fibers within peripheral nerves have distinct monodirectional structure questioning the necessity of complex multidirectional gradient vector schemes for DTI. This proof-of-concept study investigated the diagnostic utility of reduced gradient vector schemes in peripheral nerve DTI.

Methods: Three-Tesla magnetic resonance neurography of the tibial nerve using 20-vector DTI (DTI) was performed in 10 healthy volunteers, 12 patients with type 2 diabetes, and 12 age-matched healthy controls.

SLC6A4 gene variants moderate associations between childhood food insecurity and adolescent mental health.

Background: Food insecurity is a persistent concern in the United States and has been shown to affect child mental health and behavior. The SLC6A4 gene has been indicated as a moderator of the effects of chronic stress on anxiety in adolescents aged 14-21. However, it is unclear if SLC6A4 may also play a role in the effects of childhood food insecurity, a form of chronic stress, on adolescent mental health.

Magnetic resonance neurography in spinal cord injury: Imaging findings and clinical significance.

Background And Purpose: It is unknown whether changes to the peripheral nervous system following spinal cord injury (SCI) are relevant for functional recovery or the development of neuropathic pain below the level of injury. Magnetic resonance neurography (MRN) at 3 T allows detection and localization of structural and functional nerve damage. This study aimed to combine MRN and clinical assessments in individuals with chronic SCI and nondisabled controls.

Phase Angle of Bioelectrical Impedance Analysis as an Indicator for Diabetic Polyneuropathy in Type 2 Diabetes Mellitus.

Context: Due to the heterogenous clinical symptoms and deficits, the diagnosis of diabetic polyneuropathy (DPN) is still difficult in clinical routines, leading to increased morbidity and mortality.

Objective: We studied the correlation of phase angle (PhA) of bioelectrical impedance analysis (BIA) with clinical, laboratory, and physical markers of DPN to evaluate PhA as a possible diagnostic method for DPN.

Materials And Methods: In this cross-sectional observational study as part of the Heidelberg Study on Diabetes and Complications, we examined 104 healthy individuals and 205 patients with type 2 diabetes mellitus (T2D), among which 63 had DPN.

Magnetization transfer ratio of the sciatic nerve differs between patients in type 1 and type 2 diabetes.

Background: Previous studies on magnetic resonance neurography (MRN) found different patterns of structural nerve damage in type 1 diabetes (T1D) and type 2 diabetes (T2D). Magnetization transfer ratio (MTR) is a quantitative technique to analyze the macromolecular tissue composition. We compared MTR values of the sciatic nerve in patients with T1D, T2D, and healthy controls (HC).

Cluster-based prognostication in glioblastoma: Unveiling heterogeneity based on diffusion and perfusion similarities.

Background: While the association between diffusion and perfusion magnetic resonance imaging (MRI) and survival in glioblastoma is established, prognostic models for patients are lacking. This study employed clustering of functional imaging to identify distinct functional phenotypes in untreated glioblastomas, assessing their prognostic significance for overall survival.

Methods: A total of 289 patients with glioblastoma who underwent preoperative multimodal MR imaging were included.

An AI-based segmentation and analysis pipeline for high-field MR monitoring of cerebral organoids.

Cerebral organoids recapitulate the structure and function of the developing human brain in vitro, offering a large potential for personalized therapeutic strategies. The enormous growth of this research area over the past decade with its capability for clinical translation makes a non-invasive, automated analysis pipeline of organoids highly desirable. This work presents a novel non-invasive approach to monitor and analyze cerebral organoids over time using high-field magnetic resonance imaging and state-of-the-art tools for automated image analysis.

A diminished sciatic nerve structural integrity is associated with distinct peripheral sensory phenotypes in individuals with type 2 diabetes.

Aims/hypothesis: Quantitative sensory testing (QST) allows the identification of individuals with rapid progression of diabetic sensorimotor polyneuropathy (DSPN) based on certain sensory phenotypes. Hence, the aim of this study was to investigate the relationship of these phenotypes with the structural integrity of the sciatic nerve among individuals with type 2 diabetes.

Methods: Seventy-six individuals with type 2 diabetes took part in this cross-sectional study and underwent QST of the right foot and high-resolution magnetic resonance neurography including diffusion tensor imaging of the right distal sciatic nerve to determine the sciatic nerve fractional anisotropy (FA) and cross-sectional area (CSA), both of which serve as markers of structural integrity of peripheral nerves.

Microstructural changes of peripheral nerves in early multiple sclerosis: A prospective magnetic resonance neurography study.

Background And Purpose: Multiple sclerosis (MS) is a demyelinating disorder of the central nervous system (CNS). However, there is increasing evidence of peripheral nerve involvement. This study aims to characterize the pattern of peripheral nerve changes in patients with newly diagnosed MS using quantitative magnetic resonance (MR) neurography.

nanoparticle-based T cell imaging can predict therapy response towards adoptive T cell therapy in experimental glioma.

Intrinsic brain tumors, such as gliomas are largely resistant to immunotherapies including immune checkpoint blockade. Adoptive cell therapies (ACT) including chimeric antigen receptor (CAR) or T cell receptor (TCR)-transgenic T cell therapy targeting glioma-associated antigens are an emerging field in glioma immunotherapy. However, imaging techniques for non-invasive monitoring of adoptively transferred T cells homing to the glioma microenvironment are currently lacking.

Iatrogenic Air Embolisms During Endovascular Interventions: Impact of Origin and Number of Air Bubbles on Cerebral Infarctions.

Purpose: Cerebral infarctions caused by air embolisms (AE) are a feared risk in endovascular procedures; however, the relevance and pathophysiology of these AEs is still largely unclear. The objective of this study was to investigate the impact of the origin (aorta, carotid artery or right atrium) and number of air bubbles on cerebral infarctions in an experimental in vivo model.

Methods: In 20 rats 1200 or 2000 highly calibrated micro air bubbles (MAB) with a size of 85 µm were injected at the aortic valve (group Ao), into the common carotid artery (group CA) or into the right atrium (group RA) using a microcatheter via a transfemoral access, resembling endovascular interventions in humans.

Insulin Resistance Is Associated With Reduced Capillary Permeability of Thigh Muscles in Patients With Type 2 Diabetes.

Context: Insulin-mediated microvascular permeability and blood flow of skeletal muscle appears to be altered in the condition of insulin resistance. Previous studies on this effect used invasive procedures in humans or animals.

Objective: The aim of this study was to demonstrate the feasibility of a noninvasive assessment of human muscle microcirculation via dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) of skeletal muscle in patients with type 2 diabetes (T2D).