MAVRIC complements the information on FSE images after arthroplasty and is a useful additional sequence, particularly when there is concern about synovitis, periprosthetic osteolysis, or the presence of a supraspinatus tendon tear.

Sacks, Michael S.; He, Z.; Baijens, L.; Wanant, S.; Shah, P.; Sugimoto, H.; Yoganathan, A.P. Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Abstract-The mitral valve ͑MV͒ is a complex anatomical structure whose function involves a delicate force balance and synchronized function of each of its components. Elucidation of the role of each component and their interactions is critical to improving our understanding of MV function, and to form the basis for rational surgical repair. In the present study, we present the first known detailed study of the surface strains in the anterior leaflet in the functioning MV. The threedimensional spatial positions of markers placed in the central region of the MV anterior leaflet in a left ventricle-simulating flow loop over the cardiac cycle were determined. The resulting two-dimensional in-surface strain tensor was computed from the marker positions using a C 0 Lagrangian quadratic finite element. Results demonstrated that during valve closure the anterior leaflet experienced large, anisotropic strains with peak stretch rates of 500%-1000%/s. This rapid stretching was followed by a plateau phase characterized by relatively constant strain state. We hypothesized that the presence of this plateau phase was a result of full straightening of the leaflet collagen fibers upon valve closure. This hypothesis suggests that the MV collagen fibers are designed to allow leaflet coaptation followed by a dramatic increase in stiffness to prevent further leaflet deformation, which would lead to valvula...

Distortion was reduced in 3D-MAVRIC scans. Measured distortions corresponded well to theoretical calculations from frequency field map data.

Objective To correlate meniscal T2* relaxation times using ultra-short echo time (UTE) magnetic resonance imaging (MRI) with quantitative microscopic methods, and to determine the effect of meniscal repair on post-operative cartilage T2 values. Design A medial meniscal tear was created and repaired in the anterior horn of one limb of 28 crossbred mature ewes. MR scans for morphological evaluation, meniscal T2* values, and cartilage T2 values were acquired at 0, 4 and 8 months post-operatively for the Tear and Non-Op limb. Samples of menisci from both limbs were analyzed using multiphoton microscopy (MPM) analysis and biomechanical testing. Results Significantly prolonged meniscal T2* values were found in repaired limbs than in control limbs, p<0.0001. No regional differences of T2* were detected for either the repaired or control limbs in the anterior horn. Repaired limbs had prolonged cartilage T2 values, primarily anteriorly, and tended to have lower biomechanical force to failure at 8 months than Non-Op limbs. MPM autofluorescence and second harmonic generation data correlated with T2* values at 8 months (ρ=−0.48, p=0.06). Conclusions T2* mapping is sensitive to detecting temporal and zonal differences of meniscal structure and composition. Meniscal MPM and cartilage T2 values indicate changes in tissue integrity in the presence of meniscal repair.

Background MRI is predictive of adverse local tissue reactions (ALTRs) after THA but how MRI directly relates to implant surface wear, fretting, and trunnion corrosion at different articulations between implant components remains unclear. MRI generates high-contrast images to display soft tissues around arthroplasty and may provide a One of the authors certifies that she (HGP), or a member of her family, has received or may receive payments or benefits, during the study period, an amount of more than USD 1,000,000 from General Electric Healthcare (Waukesha, WI, USA). One of the authors certifies that he (MFK), or a member of his immediate family, has received or may receive payments or benefits, during the study period, an amount of USD 100,001 to USD 1,000,000 from Johnson and Johnson (New Brunswick, NJ, USA). One of the authors certifies that he (TB), or a member of his immediate family, has received or may receive payments or benefits, during the study period, an amount of less than USD 10,000 from

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ObjectiveTo examine how and to what extent medical devices using machine learning (ML) support clinician decision making.MethodsWe searched for medical devices that were (1) approved by the US Food and Drug Administration (FDA) up till February 2020; (2) intended for use by clinicians; (3) in clinical tasks or decisions and (4) used ML. Descriptive information about the clinical task, device task, device input and output, and ML method were extracted. The stage of human information processing automated by ML-based devices and level of autonomy were assessed.ResultsOf 137 candidates, 59 FDA approvals for 49 unique devices were included. Most approvals (n=51) were since 2018. Devices commonly assisted with diagnostic (n=35) and triage (n=10) tasks. Twenty-three devices were assistive, providing decision support but left clinicians to make important decisions including diagnosis. Twelve automated the provision of information (autonomous information), such as quantification of heart ejection fraction, while 14 automatically provided task decisions like triaging the reading of scans according to suspected findings of stroke (autonomous decisions). Stages of human information processing most automated by devices were information analysis, (n=14) providing information as an input into clinician decision making, and decision selection (n=29), where devices provide a decision.ConclusionLeveraging the benefits of ML algorithms to support clinicians while mitigating risks, requires a solid relationship between clinician and ML-based devices. Such relationships must be carefully designed, considering how algorithms are embedded in devices, the tasks supported, information provided and clinicians’ interactions with them.

Context:As the intensity of youth participation in athletic activities continues to rise, the number of overuse injuries has also increased. A subset of overuse injuries involves the physis, which is extremely susceptible to injury. This paper aims to review the utility of the various imaging modalities in the diagnosis and management of physeal injuries in the skeletally immature population.Evidence Acquisition:A search for the keywords pediatric, physis, growth plate, x-ray, computed tomography, magnetic resonance imaging, and overuse injury was performed using the PubMed database. No limits were set for the years of publication. Articles were reviewed for relevance with an emphasis on the imaging of growth plate injuries.Study Design:Retrospective literature review.Level of Evidence:Level 4.Results:Three major imaging modalities (radiographs, computed tomography, and magnetic resonance imaging) complement each other in the evaluation of pediatric patients with overuse injuries. However, magnetic resonance imaging is the only modality that offers direct visualization of the physis, and it also offers the best soft tissue contrast for evaluating the other periarticular structures for concomitant injury.Conclusion:Imaging has an important role in the diagnosis of physeal injuries, and the information it provides has a tremendous impact on the subsequent management of these patients.