Dynamic-MRI quantification of abdominal wall motion and deformation during breathing and muscular contraction

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Semiautomatic quantification of abdominal wall muscles deformations based on dynamic MRI image registration

International audiencein the diagnosis of abdominal muscle deficiency. Here, wepresent a dedicated semiautomatic dynamic MRI postprocessing method enablingthe quantification of spatial and temporal deformations of the antero-lateral abdominalwall muscles. Ten healthy participants were imaged during a controlled breathingsession at the L3–L4 disc level using real-time dynamic MRI at 3 T. A coarse featuretrackingstep allowed the selection of the inhalation cycle of maximum abdominalexcursion. Over this image series, the described method combines (1) a supervised2D+t segmentation procedure of the abdominal wall muscles, (2) the quantificationof muscle deformations based on masks registration, and (3) the mapping of deformationswithin muscle subzones leveraging a dedicated automatic parcellation. Thesupervised 2D+t segmentation (1) provided an accurate segmentation of the abdominalwall muscles throughout maximum inhalation with a 0.95 ± 0.03 Dice similaritycoefficient (DSC) value and a 2.3 ± 0.7 mm Hausdorff distance value while requiringonly manual segmentation of 20% of the data. The robustness of the deformationquantification (2) was indicated by high indices of correspondence between the registeredsource mask and the target mask (0.98 ± 0.01 DSC value and 2.1 ± 1.5 mmHausdorff distance value). Parcellation (3) enabled the distinction of muscle substructuresthat are anatomically relevant but could not be distinguished based on imagecontrast. The present genuine postprocessing method provides a quantitative analyticalframe that could be used in further studies for a better understanding of abdominalwall deformations in physiological and pathological situations

Tensile mechanical properties of the cervical, thoracic and lumbar porcine spinal meninges

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Preoperative Prediction of Small Bowel Length Using CT Scan and Tridimensional Reconstructions: a New Tool in Bariatric Surgery?

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