Application Of Magnetic Resonance Imaging Research Articles

Potential of Gadolinum as a Contrast Agent in MRI (Magnetic Resonance Imaging) Applications

Gadolinium has revolutionized our ability to visualize the internal structure of the human body with greater detail and better contrast. The use of gadolinium as a contrast agent has opened the door to earlier detection and more accurate diagnosis of various medical conditions, such as tumors, inflammation, vascular disorders, and more. One of the main properties of gadolinium is its magnetic properties. It has a high magnetic moment, which produces intense signals in MRI. The literature search process was carried out on various databases (PubMed, Web of Sciences, EMBASE, Cochrane Libraries, and Google Scholar) regarding the potential of gadolinium as a contrast agent in MRI applications. This study follows the preferred reporting items for systematic reviews and meta-analysis (PRISMA) recommendations. Gadolinium is an invaluable contrast agent in MRI (Magnetic Resonance Imaging) that has various potential and important benefits in the world of medical radiology. Gadolinium's unique magnetic properties allow for increased contrast in MRI images, making it easier to identify and better understand structures in the body. Gadolinium is very effective in detecting lesions, pathological changes, such as tumors, swelling, inflammation, and vascular problems. This allows early and accurate diagnosis, appropriate treatment planning, as well as monitoring disease progression. There are various types of gadolinium contrast agents that can be tailored to the needs of certain MRI examinations, such as gadopentetate dimeglumine, gadobutrol, gadodiamide, and others. Gadolinium is generally considered a safe and relatively non-toxic contrast agent. However, it is necessary to pay attention to very rare allergic reactions and the risk of accumulation in patients with impaired kidney function.

Application of Quantitative MRI in Thyroid Eye Disease: Imaging Techniques and Clinical Practices.

Thyroid eye disease (TED) is a complex autoimmune disorder that impairs various orbital structures, leading to cosmetic damage and vision loss. Magnetic resonance imaging (MRI) is a fundamental diagnostic tool utilized in clinical settings of TED, for its accurate demonstration of orbital lesions and indication of disease conditions. The application of quantitative MRI has brought a new prospect to the management and research of TED, offering more detailed information on morphological and functional changes in the orbit. Therefore, many researchers concentrated on the implementation of different quantitative MRI techniques on TED for the exploration of clinical practices. Despite the abundance of studies utilizing quantitative MRI in TED, there remain considerable barriers and disputes on the best exploitation of this tool. This could possibly be attributed to the complexity of TED and the fast development of MRI techniques. It is necessary that clinical and radiological aspects of quantitative MRI in TED be better integrated into comprehensive insights. Hence, this review traces back 30 years of publications regarding quantitative MRI utilized in TED and elucidates this promising application in the facets of imaging techniques and clinical practices. We believe that a deeper understanding of the application of quantitative MRI in TED will enhance the efficacy of the multidisciplinary management of TED. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.

Artificial intelligence for the detection of sacroiliitis on magnetic resonance imaging in patients with axial spondyloarthritis.

Magnetic resonance imaging (MRI) is important for the early detection of axial spondyloarthritis (axSpA). We developed an artificial intelligence (AI) model for detecting sacroiliitis in patients with axSpA using MRI. This study included MRI examinations of patients who underwent semi-coronal MRI scans of the sacroiliac joints owing to chronic back pain with short tau inversion recovery (STIR) sequences between January 2010 and December 2021. Sacroiliitis was defined as a positive MRI finding according to the ASAS classification criteria for axSpA. We developed a two-stage framework. First, the Faster R-CNN network extracted regions of interest (ROIs) to localize the sacroiliac joints. Maximum intensity projection (MIP) of three consecutive slices was used to mimic the reading of two adjacent slices. Second, the VGG-19 network determined the presence of sacroiliitis in localized ROIs. We augmented the positive dataset six-fold. The sacroiliitis classification performance was measured using the sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). The prediction models were evaluated using three-round three-fold cross-validation. A total of 296 participants with 4,746 MRI slices were included in the study. Sacroiliitis was identified in 864 MRI slices of 119 participants. The mean sensitivity, specificity, and AUROC for the detection of sacroiliitis were 0.725 (95% CI, 0.705-0.745), 0.936 (95% CI, 0.924-0.947), and 0.830 (95%CI, 0.792-0.868), respectively, at the image level and 0.947 (95% CI, 0.912-0.982), 0.691 (95% CI, 0.603-0.779), and 0.816 (95% CI, 0.776-0.856), respectively, at the patient level. In the original model, without using MIP and dataset augmentation, the mean sensitivity, specificity, and AUROC were 0.517 (95% CI, 0.493-0.780), 0.944 (95% CI, 0.933-0.955), and 0.731 (95% CI, 0.681-0.780), respectively, at the image level and 0.806 (95% CI, 0.729-0.883), 0.617 (95% CI, 0.523-0.711), and 0.711 (95% CI, 0.660-0.763), respectively, at the patient level. The performance was improved by MIP techniques and data augmentation. An AI model was developed for the detection of sacroiliitis using MRI, compatible with the ASAS criteria for axSpA, with the potential to aid MRI application in a wider clinical setting.

Application of functional magnetic resonance imaging for evaluation of cartilage injury effect on knee joint function by recurrent patellar dislocation.

Explore the therapeutic effect of vastus medialis oblique plasty and the reliability and applicability of functional magnetic resonance imaging as a diagnostic method for early cartilage degeneration and injury diagnosis. From July 2020 to July 2022, there were 53 patients with recurrent patellar dislocation who met the inclusion criteria for surgery, including 34 women and 19 men, aged 11 to 53 years, with an average age of 24.4 years. After patient selection, functional magnetic resonance imaging was performed before surgery. According to the presence or absence of cartilage injury, they were divided into cartilage injury group (n = 28) and non-cartilage injury group (n = 25), and underwent vastus medialis oblique plasty. Preoperative patellar axial radiographs were performed in both groups of patients to measure the patellar tilt angle and lateral patellofemoral angle. The Lysholm, Kujala, and VAS (visual analogue scale) scores were applied to assess changes in knee joint function and anterior knee pain. All patients were postoperatively followed up. The patellar tilt angle and lateral patellofemoral angle of the 2 groups were significantly improved postoperatively (P < .05), with no statistical difference between the 2 groups (P > .05). Significant differences were observed in the VAS changes between the cartilage injury group and the non-cartilage injury group before and after operation (P < .05). There was a statistical difference in VAS score between the groups (P < .05). The changes in the Lysholm and Kujala scores before and after the operation in the cartilage injury and the non-cartilage injury groups were statistically different (P < .05). There was statistical difference between the 2 groups in Lysholm score and Kujala score after operation (P < .05). Vastus medialis oblique plasty significantly improved knee joint function and pain. Patients with cartilage injury had worse preoperative and postoperative knee function than patients without cartilage injury. Functional magnetic resonance imaging can reflect the early-stage changes in the biochemical cartilage components caused by recurrent patellar dislocation.

The CALIPR framework for highly accelerated myelin water imaging with improved precision and sensitivity.

Quantitative magnetic resonance imaging (MRI) techniques are powerful tools for the study of human tissue, but, in practice, their utility has been limited by lengthy acquisition times. Here, we introduce the Constrained, Adaptive, Low-dimensional, Intrinsically Precise Reconstruction (CALIPR) framework in the context of myelin water imaging (MWI); a quantitative MRI technique generally regarded as the most rigorous approach for noninvasive, in vivo measurement of myelin content. The CALIPR framework exploits data redundancy to recover high-quality images from a small fraction of an imaging dataset, which allowed MWI to be acquired with a previously unattainable sequence (fully sampled acquisition 2 hours:57 min:20 s) in 7 min:26 s (4.2% of the dataset, acceleration factor 23.9). CALIPR quantitative metrics had excellent precision (myelin water fraction mean coefficient of variation 3.2% for the brain and 3.0% for the spinal cord) and markedly increased sensitivity to demyelinating disease pathology compared to a current, widely used technique. The CALIPR framework facilitates drastically improved MWI and could be similarly transformative for other quantitative MRI applications.

Synthesis and characterisation of erbium doped gadolinium oxide (Er:Gd2O3) nanorods

The aim of the present investigation is to synthesis the rare earth oxide sample in single phase with nanocrystalline nature which is used for magnetic resonance imaging (MRI) and other bio medical applications. Hence the present research is focussed on the synthesising of nanomaterials using co-precipitation method and few characterization techniques are adapted to characterize the synthesised samples. Erbium-doped gadolinium oxide (Er:Gd2O3) nanorods were successfully synthesized by co-precipitation method. Rare earth erbium (Er) dopant was maintained in the ratio of 5 % to avoid concentration quenching (Gd1.95Er0.05O3). The synthesized samples were then annealed to 1000 °C, in which the hexagonal phase of gadolinium hydroxides transform to cubic phase Er:Gd2O3 nanorods. Powder X-ray (XRD) diffraction analysis was used to confirm the obtained single phase. The Fourier transform infrared (FTIR) spectrum of the synthesized sample indicates the existence of all functional groups, and the fingerprint regions of gadolinium oxide (Gd2O3) and Erbium oxide (Er2O3) planar vibrations. Morphological behaviour of the synthesized Er:Gd2O3 nanorods was subjected to scanning electron microscope (SEM) fitted with energy dispersive X-ray (EDX) analysis to view the shape and size of the synthesized nanorods and to estimate the elemental composition of the synthesized samples. The results were discussed in a detailed manner.

Evaluating the diagnostic accuracy of magnetic resonance imaging in distinguishing strictures in Crohn's disease: a systematic review and meta-analysis.

This systematic review and meta-analysis sought to assess the diagnostic accuracy of magnetic resonance imaging (MRI) in distinguishing fibrotic from inflammatory strictures in Crohn's disease (CD) patients. A rigorous and systematic exploration of five key databases yielded studies that met predefined criteria. Data were extracted for a comprehensive meta-analysis using MetaDiSC and MetaDTA software, providing diagnostic accuracy measures. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool was utilized for evaluating the methodological quality and potential bias within the studies. The systematic review involved the evaluation of 7437 records, culminating in the inclusion of 22 studies. In detecting fibrotic strictures in CD patients, MRI exhibited a pooled sensitivity of 85.20% (95% CI: 76.10-91.20%) and specificity of 96.00% (95% CI: 87.80-98.70%). For differentiating fibrotic strictures from inflammatory stenosis, the sensitivity was 81.5% (95% CI: 70.2-89.20%), and the specificity was 97.2% (95% CI: 90.0-99.3%). In terms of assessing the severity of strictures, sensitivity stood at 90.4% (95% CI: 78.1-96.1%) and specificity at 89.4% (95% CI: 57.4-98.2%). The consistency of the diagnostic accuracy was observed across different geographical locations and the various reference tests applied in the studies. The results of this meta-analysis underscore the robust diagnostic accuracy of MRI in detecting fibrotic strictures, distinguishing between fibrotic and inflammatory strictures, and evaluating stricture severity in CD patients. These findings support the integration of MRI into standard diagnostic protocols for patients with CD. Further large-scale, multicenter trials are warranted to confirm these results and to identify any potential limitations associated with the application of MRI in this clinical setting.

Development trends and knowledge framework in the application of magnetic resonance imaging in prostate cancer: a bibliometric analysis from 1984 to 2022.

Prostate cancer (PCa) is the most common tumor of the male genitourinary system. With the development of imaging technology, the role of magnetic resonance imaging (MRI) in the management of PCa is increasing. The present study summarizes research on the application of MRI in the field of PCa using bibliometric analysis and predicts future research hotspots. Articles regarding the application of MRI in PCa between January 1, 1984 and June 30, 2022 were selected from the Web of Science Core Collection (WoSCC) on November 6, 2022. Microsoft Excel 2016 and the Bibliometrix Biblioshiny R-package software were used for data analysis and bibliometric indicator extraction. CiteSpace (version 6.1.R3) was used to visualize literature feature clustering, including co-occurrence analysis of countries, institutions, authors, references, and burst keywords analysis. A total of 10,230 articles were included in the study. Turkbey was the most prolific author. The USA was the most productive country and had strong partnerships with other countries. The most productive institution was Memorial Sloan Kettering Cancer Center. Journal of Magnetic Resonance Imaging and Radiology were the most productive and highest impact factor (IF) journals in the field, respectively. Timeline views showed that "#1 multiparametric magnetic resonance imaging", "#4 pi-rads", and "#8 psma" were currently the latest research hotspots. Keywords burst analysis showed that "machine learning", "psa density", "multi parametric mri", "deep learning", and "artificial intelligence" were the most frequently used keywords in the past 3 years. MRI has a wide range of applications in PCa. The USA is the leading country in this field, with a concentration of highly productive and high-level institutions. Meanwhile, it can be projected that "deep learning", "radiomics", and "artificial intelligence" will be research hotspots in the future.

Application of intravoxel incoherent motion diffusion-weighted magnetic resonance imaging on the diagnosis of breast cancer

Application of intravoxel incoherent motion diffusion-weighted magnetic resonance imaging on the diagnosis of breast cancer

Multiparametric Magnetic Resonance Imaging in Prostate Cancer Screening at the Age of 45 Years: Results from the First Screening Round of the PROBASE Trial

BackgroundMagnetic resonance imaging (MRI) has been suggested as a tool for guiding biopsy recommendations in prostate cancer (PC) screening. ObjectiveTo determine the performance of multiparametric MRI (mpMRI) in young men at age 45 yr who participated in a PC screening trial (PROBASE) on the basis of baseline prostate-specific antigen (PSA). Design, setting, and participantsParticipants with confirmed PSA ≥3 ng/ml were offered mpMRI followed by MRI/transrectal ultrasound fusion biopsy (FBx) with targeted and systematic cores. mpMRI scans from the first screening round for men randomised to an immediate PSA test in PROBASE were evaluated by local readers and then by two reference radiologists (experience >10 000 prostate MRI examinations) blinded to the histopathology. The PROBASE trial is registered as ISRCTN37591328 Outcome measurements and statistical analysisThe local and reference Prostate Imaging-Data and Reporting System (PI-RADS) scores were compared, and the sensitivity, negative predictive value (NPV), and accuracy were calculated for both readings for different cutoffs (PI-RADS 3 vs 4). Results and limitationsOf 186 participants, 114 underwent mpMRI and FBx. PC was detected in 47 (41%), of whom 33 (29%) had clinically significant PC (csPC; International Society of Urological Pathology grade group ≥2). Interobserver reliability between local and reference PI-RADS scores was moderate (k = 0.41). At a cutoff of PI-RADS 4, reference reading showed better performance for csPC detection (sensitivity 79%, NPV 91%, accuracy of 85%) than local reading (sensitivity 55%, NPV 80%, accuracy 68%). Reference reading did not miss any PC cases for a cutoff of PI-RADS <3. If PI-RADS ≥4 were to be used as a biopsy cutoff, mpMRI would reduce negative biopsies by 68% and avoid detection of nonsignificant PC in 71% of cases. ConclusionsProstate MRI in a young screening population is difficult to read. The MRI accuracy of for csPC detection is highly dependent on reader experience, and double reading might be advisable. More data are needed before MRI is included in PC screening for men at age 45 yr. Patient summaryMeasurement of prostate specific antigen (PSA) is an effective screening test for early detection of prostate cancer (PC) and can reduce PC-specific deaths, but it can also lead to unnecessary biopsies and treatment. Magnetic resonance imaging (MRI) after a positive PSA test has been proposed as a way to reduce the number of biopsies, with biopsy only recommended for men with suspicious MRI findings. Our results indicate that MRI accuracy is moderate for men aged 45 years but can be increased by a second reading of the images by expert radiologists. For broad application of MRI in routine screening, double reading may be advisable.

Application of Magnetic Resonance Imaging in Medical Rehabilitation Еffectiveness Assessing for Patients with Knee Joint Osteoarthritis: а Review

INTRODUCTION. In recent years, magnetic resonance imaging (MRI) has been increasingly used to diagnose early osteoarthritis (OA). Taking into account the fact that nowadays pharmacological agents are not effective enough and often lead to allergization of the body, there is a need to search for new non-drug methods of treatment of patients with knee joint OA that have proven effectiveness.&#x0D; AIM. To analyze scientific evidence on the use of MRI as an objective method of assessing the effectiveness of medical rehabilitation of patients with knee OA.&#x0D; MATERIALS AND METHODS. We searched for publications in the PEDro and PubMed for the period from 2000 to March 2023. Suitable articles were to reflect the use of MRI as a criterion for the effectiveness of medical rehabilitation in patients with OA of the knee joint.&#x0D; RESULTS AND DISCUSSION. As a result of a search in electronic resources, the largest number of works on the subject under study was found in PubMed. According to the literature quantitative analysis, 7256 works were identified, which reflect the use of MRI in medical rehabilitation. The publications in which the effectiveness of medical rehabilitation of patients with knee OA was evaluated by researchers using MRI accounted for 2.5 % of the total number. Most of the publications were in international databases, while they were practically absent in the Russian ones.&#x0D; CONCLUSION. Despite the scarce research on the matter, we can distinguish the following rehabilitation medicine methods with a proven effect on the ligamentous apparatus, cartilage and soft tissues of the knee joint in patients with OA, according to MRI data: shockwave therapy, physical therapy and ultrasound therapy. However, the need for further scientific research in this direction is obvious.

Clinical evaluation of radiation-induced sinusitis by MRI-based scoring system in nasopharyngeal carcinoma patients

ObjectiveTo explore the application of magnetic resonance imaging (MRI) in the evaluation of radiation-induced sinusitis (RIS), MRI-based scoring system was used to evaluate the development regularity, characteristics and influencing factors of RIS in nasopharyngeal carcinoma (NPC) patients.Patients and methodsA retrospective analysis was performed by collecting the clinical and MRI data of 346 NPC patients to analyze the characteristics and prognosis of RIS. The predictive model was constructed according to the influencing factors of RIS.Results(1) In the 2-year follow-up after radiotherapy (RT), there was significant change in L-M score in both groups of NPC patients (sinusitis before RT group: p = 0.000 vs. non-sinusitis before RT group: p = 0.000). After 6 months of RT, the L-M scores of the two groups tended to plateau (sinusitis before RT group: p = 0.311 vs. non-sinusitis before RT group: p = 0.469). (2) The prevalence of sinusitis in two groups of NPC patients (without or with sinusitis before RT) was 83% vs. 93%, 91% vs. 99%, 94% vs. 98% at 1, 6 and 24 months after RT, respectively. (3) In the patients without sinusitis before RT, the incidence of sinusitis in maxillary and anterior/posterior ethmoid, sphenoid and frontal sinuses was 87.1%, 90.0%/87.1%, 49.5%, 11.8% respectively, 1 month after RT. (4) A regression model was established according to the univariate and multivariate analysis of the factors related to RIS (smoking history: p = 0.000, time after RT: p = 0.008 and TNM staging: p = 0.040).Conclusion(1) RIS is a common complication in NPC patients after RT. This disorder progressed within 6 months after RT, stabilized and persisted within 6 months to 2 years. There is a high incidence of maxillary sinus and ethmoid sinus inflammation in NPC patients after RT. (2) Smoking history, time after RT and TNM staging were significant independent risk factors for RIS. (3) The intervention of the risk factors in the model may prevent or reduce the occurrence of RIS in NPC patients.

Research on texture images and radiomics in urology: a review of urological MR imaging applications.

Tumor volume and heterogenicity are associated with diagnosis and prognosis of urological cancers, and assessed by conventional imaging. Quantitative imaging, Radiomics, using advanced mathematical analysis may contain information imperceptible to the human eye, and may identify imaging-based biomarkers, a new field of research for individualized medicine. This review summarizes the recent literature on radiomics in kidney and prostate cancers and the future perspectives. Radiomics studies have been developed and showed promising results in diagnosis, in characterization, prognosis, treatment planning and recurrence prediction in kidney tumors and prostate cancer, but its use in guiding clinical decision-making remains limited at present due to several limitations including lack of external validations in most studies, lack of prospective studies and technical standardization. Future challenges, besides developing prospective and validated studies, include automated segmentation using artificial intelligence deep learning networks and hybrid radiomics integrating clinical data, combining imaging modalities and genomic features. It is anticipated that these improvements may allow identify these noninvasive, imaging-based biomarkers, to enhance precise diagnosis, improve decision-making and guide tailored treatment.

Lung Magnetic Resonance Imaging: Technical Advancements and Clinical Applications.

Since lung magnetic resonance imaging (MRI) became clinically available, limited clinical utility has been suggested for applying MRI to lung diseases. Moreover, clinical applications of MRI for patients with lung diseases or thoracic oncology may vary from country to country due to clinical indications, type of health insurance, or number of MR units available. Because of this situation, members of the Fleischner Society and of the Japanese Society for Magnetic Resonance in Medicine have published new reports to provide appropriate clinical indications for lung MRI. This review article presents a brief history of lung MRI in terms of its technical aspects and major clinical indications, such as (1) what is currently available, (2) what is promising but requires further validation or evaluation, and (3) which developments warrant research-based evaluations in preclinical or patient studies. We hope this article will provide Investigative Radiology readers with further knowledge of the current status of lung MRI and will assist them with the application of appropriate protocols in routine clinical practice.

Green synthesis of biocompatible Gd3+-doped ultrasmall carbon-based nanohybrids from coffee wastes

A cheap method allowing fabrication of biocompatible, ultra-small (2–10 nm) and fluorescent (λem = 425–500 nm) nanohybrids (NHs) from coffee wastes is reported. The gadolinium-doped nanohybrids (GDNHs) or gadolinium-free carbon dots (GFCDs) can be synthesized in a domestic microwave oven according to green synthesis principles. Hydrodynamic sizes, chemical composition, impact on proton magnetic resonance relaxation time and optical properties of the GDNHs and GFCDs were studied in details and compared. In particular, doping of the NHs with Gd3+ ions, up to 1.87 % w/w of gadolinium per particles’ weight, will allow their application for magnetic resonance imaging (MRI). Furthermore, cell culture tests on human adenocarcinomic alveolar basal epithelial cells line (A549) have shown high biocompatibility of the GDNHs and in a wide concentration range 100–1000 µg/ml.

Ultrasound Sonosensitizers for Tumor Sonodynamic Therapy and Imaging: A New Direction with Clinical Translation.

With the rapid development of sonodynamic therapy (SDT), sonosensitizers have evolved from traditional treatments to comprehensive diagnostics and therapies. Sonosensitizers play a crucial role in the integration of ultrasound imaging (USI), X-ray computed tomography (CT), and magnetic resonance imaging (MRI) diagnostics while also playing a therapeutic role. This review was based on recent articles on multifunctional sonosensitizers that were used in SDT for the treatment of cancer and have the potential for clinical USI, CT, and MRI applications. Next, some of the shortcomings of the clinical examination and the results of sonosensitizers in animal imaging were described. Finally, this paper attempted to inform the future development of sonosensitizers in the field of integrative diagnostics and therapeutics and to point out current problems and prospects for their application.

Super-resolution of magnetic resonance images using Generative Adversarial Networks.

Magnetic Resonance Imaging (MRI) typically comes at the cost of small spatial coverage, high expenses and long scan times. Accelerating MRI acquisition by taking less measurements yields the potential to relax these inherent forfeits. Recent breakthroughs in the field of Machine Learning have shown high-resolution (HR) images could be recovered from low-resolution (LR) signals via super-resolution (SR). In particular, a novel class of neural networks named Generative Adversarial Networks (GAN) has manifested an alternative way of conceiving models capable of generating data. GANs can learn to infer details based on some prior information, subsequently recovering missing data. Accordingly, they manifest huge potential in MRI reconstruction and acceleration tasks. This paper conducts a review on GAN-based SR methods, exhibiting the immersive ability of GANs on upscaling MRIs by a scale factor of ×4 while at the same time maintaining trustworthy and high-frequency details. Despite quantitative results suggesting SRResCycGAN outperforms other popular deep learning methods in recovering ×4 downgraded images, qualitative results show Beby-GAN holds the best perceptual quality and proves GAN-based methods hold the capacity to reduce medical costs, distress patients and even enable new MRI applications where it is currently too slow or expensive.

A 32-Channel Sleeve Antenna Receiver Array for Human Head MRI Applications at 10.5 T.

For human brain magnetic resonance imaging (MRI), high channel count ( ≥ 32 ) radiofrequency receiver coil arrays are utilized to achieve maximum signal-to-noise ratio (SNR) and to accelerate parallel imaging techniques. With ultra-high field (UHF) MRI at 7 tesla (T) and higher, dipole antenna arrays have been shown to generate high SNR in the deep regions of the brain, however the array elements exhibit increased electromagnetic coupling with one another, making array construction more difficult with the increasing number of elements. Compared to a classical dipole antenna array, a sleeve antenna array incorporates the coaxial ground into the feed-point, resulting in a modified asymmetric antenna structure with improved intra-element decoupling. Here, we extended our previous 16-channel sleeve transceiver work and developed a 32-channel azimuthally arranged sleeve antenna receive-only array for 10.5 T human brain imaging. We experimentally compared the achievable SNR of the sleeve antenna array at 10.5 T to a more traditional 32-channel loop array bult onto a human head-shaped former. The results obtained with a head shaped phantom clearly demonstrated that peripheral intrinsic SNR can be significantly improved compared to a loop array with the same number of elements- except for the superior part of the phantom where sleeve antenna elements are not located.

Investigating the effects of uniaxial pressure on the preparation of MgTiO3–CaTiO3 ceramic capacitors for MRI systems

AbstractToday's healthcare system relies on magnetic resonance imaging (MRI) for early diagnosis and treatment planning. For open MRI systems to achieve resolutions of about a hundred microns, a high voltage is required, as well as a specialized power supply. Negative–positive–zero (NP0) ceramic is selected for the fabrication of adjustable capacitors. Specifically, it stands for which is a classification based on the temperature coefficient of capacitance (TCC) of the ceramic material used in the capacitor. NP0 capacitors have a TCC of 0 ±30 ppm/°C, which means that their capacitance value does not change significantly with temperature and frequency. They are known for their stability and low losses, making them ideal for applications that require high accuracy and reliability, such as timing circuits for radio frequency (RF) applications. Here, MgTiO3–CaTiO3 ceramic is used to make an adjustable capacitor with desired properties for MRI systems. To enhance the dielectric properties of MgTiO3 ceramics, CaTiO3 was added in varying concentrations. After pressing and sintering, the resulting samples were tested using a vector network analyzer in the frequency range of 10–130 MHz. The adjustable capacitor fabricated using high co‐fired NP0 ceramic may have been used for MRI applications such as tuning circuits and matching networks, where precise capacitance values and low loss are critical. MRI systems with resonance frequencies of 128 MHz require trimmers with ceramic cores (VBreakdown = 3 kV @ 128 MHz, Cmin = 3 pF, CMax = 30 pF, and Cvariation step = 1.5 pF).

Consensus recommendations on regional interdisciplinary standardization of MRI diagnostics for multiple sclerosis in the metropolitan area of Essen

Magnetic resonance imaging (MRI) is of exceptional importance in the diagnostics and monitoring of multiple sclerosis (MS); however, a close interdisciplinary cooperation between neurologists in private practice, (neuro)radiological practices, hospitals or specialized MS centers is only rarely established. In particular, there is a lack of standardized MRI protocols for image acquisition as well as established quality parameters, which guarantee the comparability of MRI records; however, this is a fundamental prerequisite for an effective application of MRI in the treatment of MS patients, e.g., for making the diagnosis or treatment monitoring. To address these challenges a group of neurologists and (neuro)radiologists developed a consensus proposal for standardization of image acquisition, interpretation and transmission of results and for improvement in interdisciplinary cooperation. This pilot project in the metropolitan area of Essen used a modified Delphi process and was based on the most up to date scientific knowledge. The recommendation takes the medical, economic, temporal and practical aspects of MRI in MS into consideration. The model of interdisciplinary cooperation between radiologists and neurologists with the aim of a regional standardization of MRI could serve as an example for other regions of Germany in order to optimize MRI for MS.