Bone marrow edema-like signal after cartilage repair does not affect outcomes in a five-year follow-up.

Objectives: Bone marrow edema-like signal (BMELS) after cartilage repair is common, but its clinical significance remains uncertain. This study aimed to investigate the clinical and structural significance of BMELS following microfracturing (MFX) and matrix-induced autologous chondrocyte implantation (MACI).

Methods: In this multicenter study, MRI examinations were performed over a period of 5 years after cartilage repair surgery (MFX n = 17; MACI n = 28) in 45 patients.

The MOCART (magnetic resonance observation of cartilage repair tissue) 2.0 Ankle Score.

Objectives: The aim of this study was to introduce the MOCART 2.0 ankle score and evaluate its utility and reproducibility for the radiological assessment of cartilage repair tissue in the ankle joint.

Methods: The MOCART 2.

Correlations between Achilles tendon material and structural properties and quantitative magnetic resonance imagining in different athletic populations.

Achilles tendon stiffness (kAT) and Young's modulus (yAT) are important determinants of tendon function. However, their evaluation requires sophisticated equipment and time-consuming procedures. The goal of this study was twofold: to compare kAT and yAT between populations using the classical approach proposed in the literature (a combination of ultrasound and force data) and the MRI technique to understand the MRI's capability in determining differences in kAT and yAT.

Ultrahigh-field MRI: where it really makes a difference.

Background: Currently, two major magnetic resonance (MR) vendors provide commercial 7‑T scanners that are approved by the Food and Drug Administration (FDA) for clinical application. There is growing interest in ultrahigh-field MRI because of the improved clinical results in terms of morphological detail, as well as functional and metabolic imaging capabilities.

Materials And Methods: The 7‑T systems benefit from a higher signal-to-noise ratio, which scales supralinearly with field strength, a supralinear increase in the blood oxygenation level dependent (BOLD) contrast for functional MRI and susceptibility weighted imaging (SWI), and the chemical shift increases linearly with field strength with consequently higher spectral resolution.

Achilles tendon structure is associated with regular running volume and biomechanics.

Achilles tendinopathy was reported to have the highest incidence proportion of all running-related injuries. The purpose of this study was to analyse the association between the Achilles tendon structure and running activity status. 350 healthy participants (runners and inactive controls, 30-50 years) participated in this research.

Repeatability assessment of sodium (Na) MRI at 7.0 T in healthy human calf muscle and preliminary results on tissue sodium concentrations in subjects with Addison's disease.

Objectives: To determine the relaxation times of the sodium nucleus, and to investigate the repeatability of quantitative, in vivo TSC measurements using sodium magnetic resonance imaging (Na-MRI) in human skeletal muscle and explore the discriminatory value of the method by comparing TSCs between healthy subjects and patients with Addison's disease.

Materials And Methods: In this prospective study, ten healthy subjects and five patients with Addison's disease were involved. Na-MRI data sets were acquired using a density-adapted, three-dimensional radial projection reconstruction pulse sequence (DA-3DPR) with a modification for the relaxation times measurements.

Transverse Relaxation Anisotropy of the Achilles and Patellar Tendon Studied by MR Microscopy.

Background: T * anisotropy affects the clinical assessment of tendons (magic-angle artifact) and may be a source of T *-misinterpretation.

Purpose: To analyze T *-anisotropy and T *-decay of Achilles and patellar tendons in vitro at microscopic resolution using a variable-echo-time (vTE) sequence.

Study Type: Prospective.

Synthetic T-weighted images of the lumbar spine derived from an accelerated T mapping sequence: Comparison to conventional Tw turbo spin echo.

Objectives: To evaluate the diagnostic usefulness of synthetic T-weighted images of the lumbar spine derived from ten-fold undersampled k-space data using GRAPPATINI, a combination of a model-based approach for rapid T and M quantification (MARTINI) extended by generalized autocalibrating partial parallel acquistion (GRAPPA).

Materials And Methods: Overall, 58 individuals (26 female, mean age 23.3 ± 8.

Differentiation of Cartilage Repair Techniques Using Texture Analysis from T Maps.

Objective: The aim of this study was to investigate texture features from T maps as a marker for distinguishing the maturation of repair tissue after 2 different cartilage repair procedures.

Design: Seventy-nine patients, after either microfracture (MFX) or matrix-associated chondrocyte transplantation (MACT), were examined on a 3-T magnetic resonance (MR) scanner with morphological and quantitative (T mapping) MR sequences 2 years after surgery. Twenty-one texture features from a gray-level co-occurrence matrix (GLCM) were extracted.

The International Workshop on Osteoarthritis Imaging Knee MRI Segmentation Challenge: A Multi-Institute Evaluation and Analysis Framework on a Standardized Dataset.

Purpose: To organize a multi-institute knee MRI segmentation challenge for characterizing the semantic and clinical efficacy of automatic segmentation methods relevant for monitoring osteoarthritis progression.

Materials And Methods: A dataset partition consisting of three-dimensional knee MRI from 88 retrospective patients at two time points (baseline and 1-year follow-up) with ground truth articular (femoral, tibial, and patellar) cartilage and meniscus segmentations was standardized. Challenge submissions and a majority-vote ensemble were evaluated against ground truth segmentations using Dice score, average symmetric surface distance, volumetric overlap error, and coefficient of variation on a holdout test set.

Running and Physical Activity in an Air-Polluted Environment: The Biomechanical and Musculoskeletal Protocol for a Prospective Cohort Study 4HAIE (Healthy Aging in Industrial Environment-Program 4).

Far too little attention has been paid to health effects of air pollution and physical (in)activity on musculoskeletal health. The purpose of the Healthy aging in industrial environment study (4HAIE) is to investigate the potential impact of physical activity in highly polluted air on musculoskeletal health. A total of 1500 active runners and inactive controls aged 18-65 will be recruited.

Clinical implementation of accelerated T mapping: Quantitative magnetic resonance imaging as a biomarker for annular tear and lumbar disc herniation.

Objectives: This study evaluates GRAPPATINI, an accelerated T mapping sequence combining undersampling and model-based reconstruction to facilitate the clinical implementation of T mapping of the lumbar intervertebral disc.

Methods: Fifty-eight individuals (26 females, 32 males, age 23.3 ± 8.

Compositional MRI of the anterior cruciate ligament of professional alpine ski racers: preliminary report on seasonal changes and load sensitivity.

The purpose of this study was to investigate potential changes in the anterior cruciate ligament (ACL) structure of alpine ski racers over the course of an entire season using quantitative magnetic resonance imaging (T2* mapping). The dominant legs of three alpine ski racers were examined on a 3-T MR scanner four times at 3-month intervals. Multi-echo sequences for T2* maps, which were coregistered with high-resolution morphological sequences for reproducible definition of ACL regions of interest, were acquired.

Reproducibility of an Automated Quantitative MRI Assessment of Low-Grade Knee Articular Cartilage Lesions.

Objective: The goal of this study was to assess the reproducibility of an automated knee cartilage segmentation of 21 cartilage regions with a model-based algorithm and to compare the results with manual segmentation.

Design: Thirteen patients with low-grade femoral cartilage defects were included in the study and were scanned twice on a 7-T magnetic resonance imaging (MRI) scanner 8 days apart. A 3-dimensional double-echo steady-state (3D-DESS) sequence was used to acquire MR images for automated cartilage segmentation, and T2-mapping was performed using a 3D triple-echo steady-state (3D-TESS) sequence.

Frontiers of Sodium MRI Revisited: From Cartilage to Brain Imaging.

Sodium magnetic resonance imaging ( Na-MRI) is a highly promising imaging modality that offers the possibility to noninvasively quantify sodium content in the tissue, one of the most relevant parameters for biochemical investigations. Despite its great potential, due to the intrinsically low signal-to-noise ratio (SNR) of sodium imaging generated by low in vivo sodium concentrations, low gyromagnetic ratio, and substantially shorter relaxation times than for proton ( H) imaging, Na-MRI is extremely challenging. In this article, we aim to provide a comprehensive overview of the literature that has been published in the last 10-15 years and which has demonstrated different technical designs for a range of Na-MRI methods applicable for disease diagnoses and treatment efficacy evaluations.

Accelerated T2 Mapping of the Lumbar Intervertebral Disc: Highly Undersampled K-Space Data for Robust T2 Relaxation Time Measurement in Clinically Feasible Acquisition Times.

Unlabelled: T2 mapping of the intervertebral disc (IVD) can depict quantitative changes reflecting biochemical change due to loss of glycosaminoglycan content. Conventional T2 mapping is usually performed using a 2-dimensional multi-echo-spin echo sequence (2D-MESE) with long acquisition times that are generally not compatible with clinical routine. This study investigates the applicability of GRAPPATINI, a T2 mapping sequence combining undersampling, model-based reconstruction, and parallel imaging, to offer clinically feasible acquisition times in T2 mapping of the lumbar IVD.

Chondral and Osteochondral Femoral Cartilage Lesions Treated with GelrinC: Significant Improvement of Radiological Outcome Over Time and Zonal Variation of the Repair Tissue Based on T Mapping at 24 Months.

Objective: To prospectively assess the efficacy of GelrinC in the treatment of chondral and osteochondral femoral cartilage lesions using morphological (Magnetic Resonance Observation of Cartilage Repair Tissue [MOCART]) and quantitative (T-mapping) magnetic resonance imaging (MRI).

Design: This study was designed as a prospective single-arm, open label, multicenter study. Morphological magnetic resonance imaging (MRI) for MOCART assessment and T mapping was performed 1 week and 6, 12, 18, and 24 months after GelrinC implantation.

Compositional magnetic resonance imaging in the evaluation of the intervertebral disc: Axial vs sagittal T mapping.

The aim of this study was to assess T values of the lumbar intervertebral discs in the axial and sagittal plane views and assess their respective interobserver reliability. The lumbar intervertebral discs of 23 symptomatic patients (11 female; 12 male; mean age, 44.1 ± 10.

Evaluation of Meniscal Tissue after Meniscal Repair Using Ultrahigh Field MRI.

The study evaluates the meniscal tissue after primary meniscal suturing using 7-Tesla (T) magnetic resonance imaging with T* mapping at 6 and 12 months after surgery to investigate the differences between repaired meniscal tissue and healthy meniscal tissue in the medial and lateral compartment. This prospective study included 11 patients (9m/2f) with a mean age of 30.6 years (standard deviation 9.

Simple compensation method for improved half-pulse excitation profile with rephasing gradient.

Purpose: To improve the slice profile quality obtained by RF half-pulse excitation for 2D-UTE applications.

Methods: The overall first-order and zero-order phase errors along the slice-selection direction were obtained with the help of an optimization task to minimize the out-of-slice signal contamination from the calibration 1-dimenisonal (1D) profile data. The time-phase-error evolution was approximated from the k-space readout data, which were acquired primarily for correction of the readout trajectories during data regridding to the rectilinear grids.

Assessment of Low-Grade Focal Cartilage Lesions in the Knee With Sodium MRI at 7 T: Reproducibility and Short-Term, 6-Month Follow-up Data.

Objectives: Several articles have investigated potential of sodium (Na) magnetic resonance imaging (MRI) for the in vivo evaluation of cartilage health, but so far no study tested its feasibility for the evaluation of focal cartilage lesions of grade 1 or 2 as defined by the International Cartilage Repair Society. The aims of this study were to evaluate the ability of Na-MRI to differentiate between early focal lesions and normal-appearing cartilage, to evaluate within-subject reproducibility of Na-MRI, and to monitor longitudinal changes in participants with low-grade, focal chondral lesions.

Materials And Methods: Thirteen participants (mean age, 50.

Current status of functional MRI of osteoarthritis for diagnosis and prognosis.

Purpose Of Review: Osteoarthritis is a major source of disability, pain and socioeconomic cost worldwide. The epidemiology of the disorder is multifactorial including genetic, biological and biomechanical components, some of them detectable by MRI. This review provides the most recent update on MRI biomarkers which can provide functional information of the joint structures for diagnosis, prognosis and treatment response monitoring in osteoarthritis trials.