Publications by authors named "Heiland S"

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.

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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.

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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.

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  • - This study examines lesioned fascicles in the sciatic nerves of people with diabetic neuropathy (DN) to understand how these lesions relate to clinical symptoms and their underlying mechanisms.
  • - Using advanced imaging and proteomic analysis, researchers found that only individuals with type 2 diabetes (T2D) had these lesions, which showed significant damage like axonal degeneration and demyelination, along with a compromised blood nerve barrier (BNB).
  • - The results indicate that while non-lesioned fascicles from T2D donors showed neuroprotective responses, lesioned ones did not and had increased inflammatory activity, suggesting a harmful connection between the liver and nerves that could be targeted for therapy.
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  • Intravital 2P-microscopy facilitates the study of brain tumor behavior in mouse cortex, previously limited by imaging challenges in deep brain areas.
  • The new Deep3P imaging workflow combines microscopy with artificial intelligence, allowing researchers to visualize glioblastoma infiltrating up to 1.2 mm into the brain.
  • The study reveals that glioblastoma primarily invades through blood vessels in the white matter, and identifies potential imaging biomarkers associated with early tumor colonization.
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  • This study explored the use of shape radiomic features and tumor volume to classify IDH-wildtype gliomas and their relation to overall survival.
  • A total of 436 patients' preoperative MR imaging data was analyzed, leading to the identification of two distinct tumor clusters with significantly different survival outcomes (Cluster 1: median OS 23.8 months, Cluster 2: median OS 11.4 months).
  • The findings suggest that incorporating shape-radiomics along with tumor volume improves survival predictions for high-grade gliomas compared to using tumor volume alone.
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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.

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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.

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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.

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  • Glioblastoma is a really serious brain tumor that's hard to treat, but new methods using the immune system are being tested.
  • Doctors often use MRI scans to see how the tumor is doing, but sometimes it's tough because the treatment can change the brain tissue.
  • A new method called magnetic resonance elastography (MRE) might help by checking how soft the tumor is after treatment, which could show whether the therapy is working better than just looking at the tumor size.
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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.

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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.

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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.

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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.

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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.

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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).

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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.

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  • The study aimed to assess the effectiveness of magnetic resonance neurography (MRN) for tracking changes in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) over time.
  • Researchers examined 12 CIDP patients in 2016 and again in 2022, comparing nerve metrics with healthy individuals and correlating findings with clinical tests.
  • Key findings showed that nerve cross-sectional area (CSA) decreased over 6 years in CIDP patients, with initial CSA levels possibly indicating the severity of the disease's course and treatment response.
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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.

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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.

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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.

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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.

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  • Cerebral infarctions caused by iatrogenic air embolism (AE) are significant but not fully understood events during endovascular procedures.
  • In a study with 24 rats, smaller air bubbles (85 µm) led to a higher number and total volume of cerebral infarctions compared to larger bubbles (120 µm), highlighting the importance of bubble size.
  • The study's findings could improve understanding of how air embolisms cause vascular blockages, potentially leading to better prevention strategies in clinical settings.
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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.

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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).

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