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This large multicenter study of 37 magnetic resonance imaging scanners aimed at characterizing, for the first time, spatial profiles of inaccuracy (namely, Δ-profiles) in apparent diffusion coefficient (ADC) values with varying acquisition plan orientation and diffusion weighting gradient direction, using a statistical approach exploiting unsupervised clustering analysis. A diffusion-weighted imaging (DWI) protocol (b-value: 0-200-400-600-800-1000 s mm -2 ) with different combinations of acquisition plan orientation (axial/sagittal/coronal) and diffusion weighting gradient direction (anterior-posterior/left-right/feet-head) was acquired on a standard water phantom. For each acquisition setup, Δ-profiles along the 3 main orthogonal directions were characterized by fitting data with a second order polynomial function ( ar 2 + br + c ). Moreover, for each Δ-profile, the maximum minus minimum of the fitting function ( δ max ) was calculated. The parameters a , b , c , and δ max showed some significant variations between scanner systems by different manufacturers or with different static magnetic field strengths, as well as between different acquisition/estimation setups. Unsupervised clustering analysis showed two evident clusters with significantly different values of parameter a ( p < 0.0001), which can be grouped by acquisition protocol/Δ-profile direction but not scanner system. The results of ∆-profiles confirm an appreciable inter-scanner variability in ADC measurement and corroborate the importance of guarantying the reliability of ADC estimations in clinical or research studies, considering for each scanner system the specific acquisition sequence in terms of acquisition plan orientation and diffusion weighting gradient direction., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

The ocular inflammatory process may be associated with autoimmune inflammatory joint damage and can be better recovered by B-mode ultrasound, being little explored in the absent eye evaluation. This study aimed to conduct a systematic review using the Patients or Problem, Intervention, Control or Comparison, Outcomes strategy: uveitis; ultrasound, arthritis, and diagnosis. Clinical trials, meta-analysis, and randomized controlled trials that specifically address the scope of this study will be evaluated. For the search in the database, a choice of controlled vocabulary will be used with the MEDLINE MeSH platform (Medical Subject Headings). The articles must be dated from the year 2010 until the year 2020. To charting methods will be used Preferred Reporting Items for Systematic Reviews and Meta-Analyses Flow Diagram and risk of bias: the Cochrane risk of bias tool. Grade of recommendation assessment: Grading of Recommendations Assessment, Development, and Evaluation Group guidelines. Of 2909 studies, only 13 studies were included, which evaluated the use of B-mode ultrasound to assess anterior and intermediate uveitis and complications, and 5 cases showed an association of vitreitis. B-mode ultrasound can be an important benefit of complementing clinical evaluation in patients with the uveal inflammatory process associated with several autoimmune arthropathies, but more studies with better-elaborated methodology design will be necessary.