1. Discrepancies between routine sacroiliac joint MRI reporting and current expert recommendations in patients with spondyloarthritisAnna Enevold Fløistrup Hadsbjerg, Simon Lyngaa Krabbe, Nora Vladimirova, Adrian Ciurea, Kristyna Bubova, Monika Gregová, Michael J. Nissen, Burkhard Möller, Raphael Micheroli, Susanne Juhl Pedersen, Žiga Snoj, Karlo Pintarić, Žiga Rotar, 2025, original scientific article Abstract: Background Sacroiliac joint (SIJ) MRI is commonly used in diagnosing spondyloarthritis (SpA). Current Assessment of SpondyloArthritis International Society (ASAS) recommendations on reporting SIJ MRIs in patients with known or suspected axial SpA recommend always stating whether bone marrow oedema (BME), erosions and fat lesions are present/absent and whether the MRI is compatible with axial SpA. Purpose To investigate if routine care radiologists already report what has now been recommended and to assess the agreement between local radiologists and central SpA experts. Materials and methods This study includes retrospective interpretation of images acquired in routine care. Patients diagnosed with SpA enrolled in a clinical registry in one of five European countries involved in the EuroSpA Collaboration, with an available SIJ MRI and an associated local MRI report, were included. MRIs were read centrally by two readers, who registered global features (eg, MRI indicative of SpA), and various inflammatory and structural lesions as present/absent. Similar information was extracted from local reports. Findings were analysed with descriptive statistics. Results Overall, 913 patients (40 years±13, 492 men) were included. In 24%, the local MRI reports stated whether the MRI was overall indicative of SpA or not. Presence/absence of BME, erosions and fat lesions was mentioned in 88%, 48% and 29% of local reports, respectively. Inflammatory lesions were more often reported as present by local than central readers (46% vs 36%), and structural lesions less often (33% vs 50%). Conclusion This study demonstrated a large gap between the clinical practice of reporting SIJ MRIs and recent reporting recommendations. Keywords: magnetic resonance imaging, psoriatic arthritis, spondyloarthritis Published in DiRROS: 01.07.2026; Views: 133; Downloads: 94
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2. Analysis of magnetic resonance contrast agent entrapment following reversible electroporation in vitroMarko Stručić, Damijan Miklavčič, Zala Vidic, Maria Scuderi, Igor Serša, Matej Kranjc, 2024, original scientific article Abstract: Background. Administering gadolinium-based contrast agent before electroporation allows the contrast agent to enter the cells and enables MRI assessment of reversibly electroporated regions. The aim of this study was evaluation of contrast agent entrapment in CHO cells and comparison of these results with those determined by standard in vitro methods for assessing cell membrane permeability, cell membrane integrity and cell survival following electroporation. Materials and methods. Cell membrane permeabilization and cell membrane integrity experiments were performed using YO-PRO-1 dye and propidium iodide, respectively. Cell survival experiments were performed by assessing metabolic activity of cells using MTS assay. The entrapment of gadolinium-based contrast agent gadobutrol inside the cells was evaluated using T1 relaxometry of cell suspensions 25 min and 24 h after electroporation and confirmed by inductively coupled plasma mass spectrometry. Results. Contrast agent was detected 25 min and 24 h after the delivery of electric pulses in cells that were reversibly electroporated. In addition, contrast agent was present in irreversibly electroporated cells 25 min after the delivery of electric pulses but was no longer detected in irreversibly electroporated cells after 24 h. Inductively coupled plasma mass spectrometry showed a proportional decrease in gadolinium content per cell with shortening of T1 relaxation time (R2 = 0.88 and p = 0.0191). Conclusions. Our results demonstrate that the contrast agent is entrapped in cells exposed to reversible electroporation but exits from cells exposed to irreversible electroporation within 24 h, thus confirming the hypothesis on which detection experiments in vivo were based. Keywords: electroporation, membrane permeabilization, magnetic resonance contrast agent, T1 relaxometry Published in DiRROS: 26.06.2026; Views: 107; Downloads: 84
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3. Quantitative measurement of magnetic force in basic and precious dental alloys for porcelain techniquePeter Majerič, Milan Svetec, Peter Mihor, Zvonko Jagličić, Aleksandra Kocijan, Rebeka Rudolf, 2026, original scientific article Abstract: Precious dental alloys based on gold, platinum, palladium or silver exhibit excellent corrosion resistance, high biocompatibility and optimal mechanical properties for use in prosthetic dentistry. In comparison, base dental alloys based on chromium, cobaltor nickel are cheaper, have excellent mechanical properties but poorer corrosion resistance and biocompatibility. This research examined the magnetic properties of dental alloys in a magnetic field, which vary with composition and electronic structure. Materials can be classified as diamagnetic, paramagnetic or ferromagnetic, depending on how they respond to an external magnetic field, with noble metals usually showing weak or negligible magnetic behaviour. Experimental results of magnetic force measurements in precious dental alloys have shown that most exhibit diamagnetic properties, being weakly repelled by a magnetic field, and do not retain any magnetization when the magnetic field is removed. One of the tested precious-metal alloys ex-hibited paramagnetic behaviour, indicating a weak attraction in a magnetic field. In contrast, all studied dental base-metal alloys exhibited stronger paramagnetic interactions with magnetic fields. Diamagnetic properties of precious-metal dental alloys present a significant advantage in the medical environment, especially in magnetic resonance imaging (MRI) as diamagnetic materials do not interfere with magnetic fields and thus reduce image distortion and patient risk during MRI. However, paramagnetic base-metal dental alloys can cause local heating or imaging artefacts under MRI conditions. Therefore, precious-metal dental alloys are more suitable for patients who may require MRI, as they combine functional durability with greater safety in medical diagnostics. Keywords: base and noble dental alloys, magnetic force, magnetic resonance imaging safety, characterization Published in DiRROS: 22.06.2026; Views: 165; Downloads: 139
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4. Anharmonic quantum effects of implanted muons : route to probing nuclear quantum behavior in solidsFabian Hotz, Matjaž Gomilšek, Tina Arh, Thomas Hicken, Polona Umek, Andrej Zorko, Hubertus Luetkens, 2026, original scientific article Abstract: The quantum behavior of light particles in solids gives rise to phenomena that cannot be captured by a classical description. We show that muon spin spectroscopy (μSR), when paired with a quantum-mechanical treatment of the implanted muon, becomes a sensitive and direct probe of nuclear quantum effects. By modeling the muon as a spatially extended quantum particle, our approach captures strong anharmonic behavior. We demonstrate this in Zn-barlowite, which serves as a nontrivial test case due to its structurally complex lattice and the presence of both fluorine and hydroxyl groups. Our results establish a route for extracting nuclear quantum signatures from μSR data and open different opportunities for studying light nuclei such as hydrogen and lithium in systems where quantum fluctuations shape structure and function. Keywords: defects, magnetic interactions, magnetization dynamics, spin dynamics, density functional theory, muon spin resonance Published in DiRROS: 19.06.2026; Views: 195; Downloads: 141
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5. The influence of late gadolinium enhancement cardiac magnetic resonance image analysis imprecision on myocardial damage quantification in patients with myocarditis : a pilot studyLana Kralj, Andreja Černe Čerček, Alja Gomišček, Borut Kirn, 2024, original scientific article Abstract: Background: Myocardial damage in myocarditis is assessed through late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR). Variability in quantifying myocarditis extent results from imprecise image segmentation and inconclusive data on quantification method selection. To improve analysis precision, segmentation steps are systematically ranked based on their inherent risks of error. Additionally, data on two distinct quantification methods are presented. Methods: Using newly developed software, four experts analyzed five LGE-CMR left ventricular (LV) short-axis (SAx) images of myocarditis patients in three sessions. Regions of interest (ROIs) (myocardial (ROImyoc), reference (ROIref), and exclusion region (ROIexcl)) were identified and used to calculate LGE extent with 3σ (intensity above three standard deviations (σ) in reference) and the full width at half maximum (FWHM) method (intensity above 50% of maximum signal in reference). The reference LGE extent was calculated and the influence of the ROIs on LGE extent variability was determined. Interobserver and intraobserver variability were evaluated as 1-intraclass correlation coefficient (ICC). Results: LGE extent variability was 6.2 ± 0.6% for 3σ and 4.0 ± 0.6% for FWHM. The contributions of ROImyoc, ROIref, and ROIexcl were 1.5 ± 0.2%, 2.7 ± 0.4%, and 2 ± 0.3%, respectively, for 3σ, and 1.1 ± 0.1%, 1.6 ± 0.4%, and 1.3 ± 0.3%, respectively, for FWHM. LGE extent was lower in FWHM. Interobserver variability was 0.56 for 3σ and 0.43 for FWHM. The intraobserver variability was higher for the 3σ method in all four observers. Conclusion: ROIref selection contributed most to LGE extent variability. FWHM yielded lower LGE extent and lower inter- and intraobserver variability. Due to low statistical significance, the findings are only partially confirmed. Keywords: myocarditis, cardiac magnetic resonance, variability, full width at half maximum, thresholding methods, segmentation Published in DiRROS: 03.06.2026; Views: 223; Downloads: 130
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6. Sex differences in brain atropy in dementia with Lewy bodiesJavier Oltra, Annegret Habich, Christopher G. Schwarz, Zuzana Nedelska, Anna Inguanzo, Patricia Diaz-Galvan, Val J. Lowe, Ketil Oppendal, Dianne Gove, Milica Gregorič Kramberger, 2024, original scientific article Keywords: atrophy, dementia with Lewy bodies, magnetic resonance imaging, sex differences Published in DiRROS: 03.06.2026; Views: 188; Downloads: 170
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7. Molecular dynamics in tetrafluoridoborate salts of divalent metals studied by nuclear magnetic resonance spectroscopyAnton Gradišek, Kristian Radan, Matic Lozinšek, 2026, original scientific article Abstract: Fluoridoborate (BF4−) salts are linchpins across synthesis and catalysis, key constituents of ionic liquids, and promising electro-lytes and additives in next-generation multivalent rechargeable batteries. Despite this reach, quantitative links between crystalchemistry and anion motion remain scarce. Here, we present a molecular dynamics study of four such salts, namely M(BF4 ) 2(M = Ca 2+, Sr 2+, Ba 2+, Cd2+), by means of nuclear magnetic resonance spectroscopy (NMR). We measured the temperature depen-dence of static 19 F NMR spectra and spin-lattice relaxation and determined the values of activation energies for the thermally-activated reorientations for the BF4− tetrahedra. We draw a comparison with systems with similar geometries, such as thewell-studied complex metal borohydrides. Keywords: fluorides, metal tetrafluoridoborates, molecular dynamics, nuclear magnetic resonance spectroscopy Published in DiRROS: 13.03.2026; Views: 349; Downloads: 304
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9. Quantitative MRI Assessment of supraspinatus tendon remodeling following a single platelet-rich plasma injection using T2 mapping and relaxation time profilingKarlo Pintarić, Andrej Vovk, Vladka Salapura, Žiga Snoj, Jernej Vidmar, 2025, original scientific article Abstract: Background: Quantitative magnetic resonance imaging (MRI) techniques such as T2 mapping may detect early tendon changes following biologic therapies. This study aimed to assess the structural remodeling of the supraspinatus tendon using mean T2 values and T2 distribution profiles after an ultrasound (US)-guided single platelet-rich plasma (PRP) injection. Methods: Twenty-six patients with symptomatic supraspinatus tendinopathy were divided into tendinosis (n = 9) and partial tear (n = 13) groups. T2 mapping and clinical evaluations (shoulder pain and disability index questionnaire (SPADI), Constant-Murley score) were conducted at baseline and 6 months post-PRP. Mean T2 values were measured in three tendon segments (lateral, middle, and medial), and T2 profiles were compared to asymptomatic controls. Results: Clinical outcomes showed significant improvement in both the tendinosis and partial tear groups at the 6-month follow-up. Although no significant changes were observed in the mean T2 relaxation times across tendon segments following PRP treatment, T2 distribution profiling revealed statistically significant alterations in both groups. In the tendinosis group, post-treatment T2 profiles approached those of the asymptomatic controls, suggesting structural remodeling consistent with tendon healing. Conclusions:T2 mapping is an effective tool for detecting tendon remodeling following PRP therapy. Structural improvements indicative of tissue healing were observed in cases of tendinosis, but not in partial tendon tears. These findings support the use of T2 mapping-particularly the T2 distribution profiling-as a quantitative biomarker for assessing treatment response to PRP. Keywords: T2 mapping, magnetic resonance imaging, supraspinatus tendon Published in DiRROS: 27.02.2026; Views: 335; Downloads: 223
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10. Sacroiliac joint involvement in psoriatic arthritis – MRI, radiographic and clinical findings in 581 European routine care patientsNora Vladimirova, Anna Enevold Fløistrup Hadsbjerg, Simon Lyngaa Krabbe, Adrian Ciurea, Kristyna Bubova, Monika Gregová, Michael J. Nissen, Burkhard Möller, Raphael Micheroli, Susanne Pedersen, Žiga Snoj, Karlo Pintarić, Žiga Rotar, 2025, original scientific article Abstract: Background: Axial involvement in psoriatic arthritis (axPsA) is associated with more severe disease and increased pain, yet no consensus definition of axPsA exists. This study aims to describe the occurrence and characteristics of MRI and radiographic sacroiliac joint (SIJ) involvement in a European PsA cohort. Methods: Patients with a clinical diagnosis of PsA or of axial spondyloarthritis with psoriasis and available routine care SIJ MRIs were included from five European registries in the EuroSpA collaboration. SIJ MRIs and radiographs were centrally assessed for inflammatory and structural lesions, differential diagnoses, and globally evaluated for SpAindicative findings. Results: Among 581 PsA patients (mean age 45 years, 47% male), 31% exhibited SpA-indicative SIJ-MRI findings (MRI-axPsA). In MRI-axPsA patients, the most common lesions were bone marrow edema (BME) (69%), erosions (68%), and fat lesions (58%), generally present bilaterally. BME≥1 cm, inflammation in an erosion cavity, capsulitis, fat lesions≥1 cm, backfill, and ankylosis were observed almost exclusively in MRI-AxPsA patients. Differential diagnoses included osteitis condensans ilii (8%), probable strain-related BME (11%) and degenerative disease (16%). Among 259 patients with radiographs, 29% met the radiographic mNY criteria for ankylosing spondylitis and 38% had SpAindicative MRI findings. Male sex, HLA-B27 positivity, elevated CRP and history of inflammatory back pain (but not current back pain) were independently associated with MRI-detected axial involvement. Conclusion: In this large European cohort, one-third of routine care PsA patients had axial involvement, based on global SIJ MRI assessment. The study supports incorporating MRI into the future definition of axPsA to enable early identification. Keywords: axial psoriatic arthritis, axial spondyloarthritis, imaging, magnetic resonance imaging Published in DiRROS: 24.02.2026; Views: 590; Downloads: 303
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