Publications by authors named "Gerd Melkus"

Objective: The purpose of this study was to determine whether gray matter volume and diffusion-based metrics in associated white matter changed in breachers who had neuroimaging performed at two timepoints. A secondary purpose was to compare these changes in a group who had a one-year interval between their imaging timepoints to a group that had a two-year interval between imaging.

Methods: Between timepoints, clusters with significantly different gray matter volume were used as seeds for reconstruction of associated structural networks using diffusion metrics.

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  • - The study aimed to see if structural network parameters provide additional insights into the effectiveness of MS treatment after immunoablation and autologous stem cell transplantation, focusing on patients whose relapses were suppressed.
  • - Researchers analyzed data from 24 MS patients before and after treatment, assessing brain health markers like N-acetylaspartate to creatine ratio (NAA/Cr) and serum neurofilament light chain (sNfL) in relation to network parameters.
  • - Results showed that changes in network parameters post-treatment were significantly linked to improved measures of neuronal injury, suggesting these parameters could serve as valuable indicators of disease severity in progressive MS.
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Background: The Canadian Special Operations Forces Command conducts explosives operations and training which exposes members to explosive charges at close proximity. This 5-year longitudinal trial was conducted in follow-up to our initial trial which examined military breachers with MRI and EEG pre and post blast exposure.

Purpose: To examine brain MRI findings in military personnel exposed to multiple repeated blast exposures.

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  • Scientists studied a girl with many health problems, like weakness and breathing issues, but they didn't know the cause.
  • They used advanced DNA testing to find changes in her genes, discovering two specific variants linked to her condition.
  • These changes affected how a key gene called SOX8 works, leading to problems that explained her symptoms and showed how complex our genes can be.
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  • The study investigates the use of advanced neuroimaging (ASL) to understand brain blood flow differences in youths with concussions compared to those with orthopedic injuries (OIs) at 72 hours and 4 weeks post-injury.
  • It analyzes patterns of abnormal brain perfusion, recovery trends, and connections between brain perfusion and symptom severity in both groups.
  • Results include data from 70 youths with concussions and 29 with OIs, showing that while global perfusion differences weren't significant, there were noteworthy findings in regional perfusion related to concussions.
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Congenital myopathy with tremor (MYOTREM) is a recently described disorder characterized by mild myopathy and a postural and intention tremor present since early infancy. MYOTREM is associated with pathogenic variants in MYBPC1 which encodes slow myosin-binding protein C, a sarcomere protein with regulatory and structural roles. Here, we describe a family with three generations of variably affected members exhibiting a novel variant in MYBPC1 (c.

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Knowledge is rapidly accumulating on basic roles and modulation of bone-marrow adipose tissue (BMAT). Among key modulators are physical forces on bones as exerted by gravity and exercise. Studying humans returning from space has revealed that, in addition to physical forces, local energetics within the bone marrow can play modulatory roles.

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Oculopharyngeal muscular dystrophy (OPMD) is a rare, primarily autosomal dominant, late onset muscular dystrophy commonly presenting with ptosis, dysphagia, and subsequent weakness of proximal muscles. Although OPMD diagnosis can be confirmed with high confidence by genetic testing, the slow progression of OPMD poses a significant challenge to clinical monitoring and a barrier to assessing the efficacy of treatments during clinical trials. Accordingly, there is a pressing need for more sensitive measures of OPMD progression, particularly those which do not require a muscle biopsy.

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Space travel requires metabolic adaptations from multiple systems. While vital to bone and blood production, human bone marrow adipose (BMA) tissue modulation in space is unknown. Here we show significant downregulation of the lumbar vertebrae BMA in 14 astronauts, 41 days after landing from six months' missions on the International Space Station.

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Chronic kidney disease (CKD) and acute kidney injury (AKI) are ongoing global health burdens. Glomerular filtration rate (GFR) is the gold standard measure of kidney function, with clinical estimates providing a global assessment of kidney health without spatial information of kidney- or region-specific dysfunction. The addition of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) to the anatomical imaging already performed would yield a 'one-stop-shop' for renal assessment in cases of suspected AKI and CKD.

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Objective: : To determine the prevalence of 'fat-poor' adrenal adenomas at chemical-shift-MRI.

Materials And Methods: : This prospective IRB approved study identified 104 consecutive patients with 127 indeterminate adrenal masses that underwent 1.5-T chemical-shift-MRI between 2021-2023.

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Objectives: To compare the MRI texture profile of acetabular subchondral bone in normal, asymptomatic cam positive, and symptomatic cam-FAI hips and determine the accuracy of a machine learning model for discriminating between the three hip classes.

Methods: A case-control, retrospective study was performed including 68 subjects (19 normal, 26 asymptomatic cam, 23 symptomatic cam-FAI). Acetabular subchondral bone of unilateral hip was contoured on 1.

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Background And Objectives: Coenzyme Q (CoQ) is an important electron carrier and antioxidant. The COQ7 enzyme catalyzes the hydroxylation of 5-demethoxyubiquinone-10 (DMQ), the second-to-last step in the CoQ biosynthesis pathway. We report a consanguineous family presenting with a hereditary motor neuropathy associated with a homozygous c.

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Purpose: Rapid identification of hematoma expansion (HE) risk at baseline is a priority in intracerebral hemorrhage (ICH) patients and may impact clinical decision making. Predictive scores using clinical features and Non-Contract Computed Tomography (NCCT)-based features exist, however, the extent to which each feature set contributes to identification is limited. This paper aims to investigate the relative value of clinical, radiological, and radiomics features in HE prediction.

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Article Synopsis
  • Oculopharyngeal muscular dystrophy (OPMD) is a genetic disorder characterized by symptoms like drooping eyelids, severe swallowing issues, and muscle weakness, making it hard to diagnose atypical cases.
  • Researchers conducted a study using MRI to assess its effectiveness in diagnosing and tracking OPMD progression by evaluating muscle fat replacement in various muscles among patients with OPMD, other muscular dystrophies, and healthy controls.
  • The results indicated that MRI could differentiate OPMD from other conditions based on fat replacement in the tongue, which also correlated with the severity of swallowing difficulties, suggesting MRI could be a useful tool for clinical trials in OPMD.
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Objective: To compare image quality and detection of microscopic fat in adrenal adenomas imaged with 2-D and 3-D chemical shift imaging (CSI) and, to derive parameters which best match 2-D and 3-D-CSI.

Methods: This two-phase, retrospective, and phantom + prospective study was IRB approved. First, a retrospective assessment of 50 consecutive adrenal adenomas imaged at 1.

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Background And Objective: The prevalence and role of the motor band sign (MBS) remain unclear in motor neuron disease. We report the frequency of MBS in amyotrophic lateral sclerosis (ALS) and primary lateral sclerosis (PLS), its correlation with clinical upper motor neuron (UMN) signs, and prognostic value in ALS.

Methods: We conducted a retrospective study of ALS, PLS, and controls with retrievable MRI between 2010 and 2018.

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A new CEST-MRI contrast agent, 2-HYNIC, capable of sensing aromatic aldehydes is reported. Pyridoxal 5'-phosphate, a key Vitamin B metabolite necessary for >140 biotransformations was mapped by CEST-MRI and in lung cancer. 2-HYNIC provided access to this key biomarker associated with a variety of human diseases.

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Background: The quantitative assessment of supraspinatus tendons by conventional magnetic resonance is limited by low contrast-to-noise ratio (CNR). Magnetic resonance imaging (MRI) scanners operating at 7 Tesla offer high signal-to noise ratio (SNR), low CNR and high spatial resolution that are well-suited for rapidly relaxing tissues like tendons. Few studies have applied T2 and T2* mapping to musculoskeletal imaging and to the rotator cuff tendons.

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Background: Diffusion weighted imaging (DWI) is fundamental for prostate cancer (PCa) detection with MRI; however, limited by susceptibility artifact from hip prosthesis.

Purpose: To evaluate image quality and ability to detect PCa with quantitative T2-mapping and DWI in men with hip prosthesis undergoing prostate MRI.

Study Type: Prospective, cross-sectional study.

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Background: Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is a validated technique for evaluating cartilage health in developmental dysplasia of the hip (DDH), which can be a helpful prognosticator for the response to surgical treatments. dGEMRIC requires intravenous injection of gadolinium contrast, however, which adds time, expense, and possible adverse reactions to the imaging procedure. Newer MRI cartilage mapping techniques such as T1 rho (ρ) and T2* have been performed in the hip without the need for any contrast, although it is unknown whether they are equivalent to dGEMRIC.

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Methods: In a prospective clinical trial, 20 healthy men participated in a 60-day, 6-degree head-down tilt bed rest study. Serial 3-T magnetic resonance (MR) imaging measures of the lumbar spine were performed at baseline, after 57 days of bed rest, and at 30, 360, and 720 days of reambulation (100 MR imaging scans). Proton density with and without fat saturation, 2-point Dixon, and single-voxel MR spectroscopy techniques were used to assess bone marrow composition (300 measures).

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Background: The edited magnetic resonance spectroscopy (MRS) technique has not yet been formally evaluated for the in vivo detection of 2-hydroxyglutarate (2-HG) in patients with gliomas of various grades.

Purpose: To evaluate the diagnostic accuracy of edited MRS in the preoperative identification of the isocitrate dehydrogenase (IDH) mutation status in patients with gliomas.

Study Type: Prospective.

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Prostate MRI is reported in clinical practice using the Prostate Imaging and Data Reporting System (PI-RADS). PI-RADS aims to standardize, as much as possible, the acquisition, interpretation, reporting, and ultimately the performance of prostate MRI. PI-RADS relies upon mainly subjective analysis of MR imaging findings, with very few incorporated quantitative features.

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