The Experts below are selected from a list of 126 Experts worldwide ranked by ideXlab platform

Simona Celi - One of the best experts on this subject based on the ideXlab platform.

  • Fast interactive CFD evaluation of hemodynamics assisted by RBF mesh morphing and reduced order models: the case of aTAA modelling
    International Journal on Interactive Design and Manufacturing (IJIDeM), 2020
    Co-Authors: Marco Evangelos Biancolini, Katia Capellini, Emiliano Costa, Corrado Groth, Simona Celi
    Abstract:

    The medical digital twin is emerging as a viable opportunity to provide patient-specific information useful for treatment, prevention and surgical planning. A bottleneck toward its effective use when computational fluid dynamics (CFD) techniques and tools are adopted for the high fidelity prediction of blood flow, is the significant computing cost required. Reduced order models (ROM) looks to be a promising solution for facing the aforementioned limit. In fact, once ROM data processing is accomplished, the consumption stage can be performed outside the computer-aided engineering software adopted for simulation and, in addition, it could be also implemented on interactive software visualization interfaces that are commonly employed in the medical context. In this paper we demonstrate the soundness of such a concept by numerically investigating the effect of the bulge shape for the ascending Thoracic Aorta Aneurysm case. Radial basis functions (RBF) based mesh morphing enables the implementation of a parametric shape, which is used to build up the ROM framework and data. The final result is an inspection tool capable to visualize, interactively and almost in real-time, the effect of shape parameters on the entire flow field. The approach is first verified considering a morphing action representing the progression from an average healthy patient to an average aneurismatic one (Capellini et al. in Proceedings VII Meeting Italian Chapter of the European Society of Biomechanics (ESB-ITA 2017), 2017; Capellini et al. in J. Biomech. Eng. 140(11):111007-1–111007-10, 2018). Then, a set of shape parameters, suitable to consistently represent a widespread number of possible bulge configurations, are defined and accordingly generated. The concept is showcased taking into account the steady flow field at systolic peak conditions, using ANSYS®Fluent®and its ROM environment for CFD and ROM calculations respectively, and the RBF Morph^TM software for shape parametrization.

  • computational fluid dynamic study for ataa hemodynamics an integrated image based and radial basis functions mesh morphing approach
    Journal of Biomechanical Engineering-transactions of The Asme, 2018
    Co-Authors: Katia Capellini, Emanuele Vignali, Emiliano Costa, Emanuele Gasparotti, Marco Evangelos Biancolini, Luigi Landini, Vincenzo Positano, Simona Celi
    Abstract:

    : We present a novel framework for the fluid dynamics analysis of healthy subjects and patients affected by ascending Thoracic Aorta Aneurysm (aTAA). Our aim is to obtain indications about the effect of a bulge on the hemodynamic environment at different enlargements. 3D surface models defined from healthy subjects and patients with aTAA, selected for surgical repair, were generated. A representative shape model for both healthy and pathological groups has been identified. A morphing technique based on radial basis functions (RBF) was applied to mould the shape relative to healthy patient into the representative shape of aTAA dataset to enable the parametric simulation of the aTAA formation. CFD simulations were performed by means of a finite volume solver using the mean boundary conditions obtained from three-dimensional (PC-MRI) acquisition. Blood flow helicity and flow descriptors were assessed for all the investigated models. The feasibility of the proposed integrated approach of RBF morphing technique and CFD simulation for aTAA was demonstrated. Significant hemodynamic changes appear at the 60% of the bulge progression. An impingement of the flow toward the bulge was observed by analyzing the normalized flow eccentricity index.

Gene G Hunder - One of the best experts on this subject based on the ideXlab platform.

  • polymyalgia rheumatica and giant cell arteritis
    The Lancet, 2008
    Co-Authors: Carlo Salvarani, Fabrizio Cantini, Gene G Hunder
    Abstract:

    Polymyalgia rheumatica and giant-cell arteritis are closely related disorders that affect people of middle age and older. They frequently occur together. Both are syndromes of unknown cause, but genetic and environmental factors might have a role in their pathogenesis. The symptoms of polymyalgia rheumatica seem to be related to synovitis of proximal joints and extra-articular synovial structures. Giant-cell arteritis primarily affects the Aorta and its extracranial branches. The clinical findings in giant-cell arteritis are broad, but commonly include visual loss, headache, scalp tenderness, jaw claudication, cerebrovascular accidents, aortic arch syndrome, Thoracic Aorta Aneurysm, and dissection. Glucocorticosteroids are the cornerstone of treatment of both polymyalgia rheumatica and giant-cell arteritis. Some patients have a chronic course and might need glucocorticosteroids for several years. Adverse events of glucocorticosteroids affect more than 50% of patients. Trials of steroid-sparing drugs have yielded conflicting results. A greater understanding of the molecular mechanisms involved in the pathogenesis should provide new targets for therapy.

Foster A Hays - One of the best experts on this subject based on the ideXlab platform.

  • Thoracic Aorta Aneurysm repair using the right axillary approach
    Journal of Vascular Surgery, 2011
    Co-Authors: Samuel S Ahn, Robert W Feldtman, Foster A Hays
    Abstract:

    We present a 66-year-old man with a 5.7-cm saccular descending Thoracic aortic Aneurysm and a smaller 4.6-cm Aneurysm just proximal to the celiac artery. The patient was judged to be too risky for open surgical repair because of poor anatomy and health. Previous stenting of the iliac arteries for a kinked aortoiliac open graft precluded conventional endovascular Aneurysm repair. The descending Thoracic Aorta was successfully repaired using endovascular methods with a standard Talent (Medtronic, Los Angeles, Calif) Thoracic proximal main stent graft, which was reverse-loaded onto the delivery device and delivered antegrade through the right axillary artery.

Marco Evangelos Biancolini - One of the best experts on this subject based on the ideXlab platform.

  • Fast interactive CFD evaluation of hemodynamics assisted by RBF mesh morphing and reduced order models: the case of aTAA modelling
    International Journal on Interactive Design and Manufacturing (IJIDeM), 2020
    Co-Authors: Marco Evangelos Biancolini, Katia Capellini, Emiliano Costa, Corrado Groth, Simona Celi
    Abstract:

    The medical digital twin is emerging as a viable opportunity to provide patient-specific information useful for treatment, prevention and surgical planning. A bottleneck toward its effective use when computational fluid dynamics (CFD) techniques and tools are adopted for the high fidelity prediction of blood flow, is the significant computing cost required. Reduced order models (ROM) looks to be a promising solution for facing the aforementioned limit. In fact, once ROM data processing is accomplished, the consumption stage can be performed outside the computer-aided engineering software adopted for simulation and, in addition, it could be also implemented on interactive software visualization interfaces that are commonly employed in the medical context. In this paper we demonstrate the soundness of such a concept by numerically investigating the effect of the bulge shape for the ascending Thoracic Aorta Aneurysm case. Radial basis functions (RBF) based mesh morphing enables the implementation of a parametric shape, which is used to build up the ROM framework and data. The final result is an inspection tool capable to visualize, interactively and almost in real-time, the effect of shape parameters on the entire flow field. The approach is first verified considering a morphing action representing the progression from an average healthy patient to an average aneurismatic one (Capellini et al. in Proceedings VII Meeting Italian Chapter of the European Society of Biomechanics (ESB-ITA 2017), 2017; Capellini et al. in J. Biomech. Eng. 140(11):111007-1–111007-10, 2018). Then, a set of shape parameters, suitable to consistently represent a widespread number of possible bulge configurations, are defined and accordingly generated. The concept is showcased taking into account the steady flow field at systolic peak conditions, using ANSYS®Fluent®and its ROM environment for CFD and ROM calculations respectively, and the RBF Morph^TM software for shape parametrization.

  • computational fluid dynamic study for ataa hemodynamics an integrated image based and radial basis functions mesh morphing approach
    Journal of Biomechanical Engineering-transactions of The Asme, 2018
    Co-Authors: Katia Capellini, Emanuele Vignali, Emiliano Costa, Emanuele Gasparotti, Marco Evangelos Biancolini, Luigi Landini, Vincenzo Positano, Simona Celi
    Abstract:

    : We present a novel framework for the fluid dynamics analysis of healthy subjects and patients affected by ascending Thoracic Aorta Aneurysm (aTAA). Our aim is to obtain indications about the effect of a bulge on the hemodynamic environment at different enlargements. 3D surface models defined from healthy subjects and patients with aTAA, selected for surgical repair, were generated. A representative shape model for both healthy and pathological groups has been identified. A morphing technique based on radial basis functions (RBF) was applied to mould the shape relative to healthy patient into the representative shape of aTAA dataset to enable the parametric simulation of the aTAA formation. CFD simulations were performed by means of a finite volume solver using the mean boundary conditions obtained from three-dimensional (PC-MRI) acquisition. Blood flow helicity and flow descriptors were assessed for all the investigated models. The feasibility of the proposed integrated approach of RBF morphing technique and CFD simulation for aTAA was demonstrated. Significant hemodynamic changes appear at the 60% of the bulge progression. An impingement of the flow toward the bulge was observed by analyzing the normalized flow eccentricity index.

Katia Capellini - One of the best experts on this subject based on the ideXlab platform.

  • Fast interactive CFD evaluation of hemodynamics assisted by RBF mesh morphing and reduced order models: the case of aTAA modelling
    International Journal on Interactive Design and Manufacturing (IJIDeM), 2020
    Co-Authors: Marco Evangelos Biancolini, Katia Capellini, Emiliano Costa, Corrado Groth, Simona Celi
    Abstract:

    The medical digital twin is emerging as a viable opportunity to provide patient-specific information useful for treatment, prevention and surgical planning. A bottleneck toward its effective use when computational fluid dynamics (CFD) techniques and tools are adopted for the high fidelity prediction of blood flow, is the significant computing cost required. Reduced order models (ROM) looks to be a promising solution for facing the aforementioned limit. In fact, once ROM data processing is accomplished, the consumption stage can be performed outside the computer-aided engineering software adopted for simulation and, in addition, it could be also implemented on interactive software visualization interfaces that are commonly employed in the medical context. In this paper we demonstrate the soundness of such a concept by numerically investigating the effect of the bulge shape for the ascending Thoracic Aorta Aneurysm case. Radial basis functions (RBF) based mesh morphing enables the implementation of a parametric shape, which is used to build up the ROM framework and data. The final result is an inspection tool capable to visualize, interactively and almost in real-time, the effect of shape parameters on the entire flow field. The approach is first verified considering a morphing action representing the progression from an average healthy patient to an average aneurismatic one (Capellini et al. in Proceedings VII Meeting Italian Chapter of the European Society of Biomechanics (ESB-ITA 2017), 2017; Capellini et al. in J. Biomech. Eng. 140(11):111007-1–111007-10, 2018). Then, a set of shape parameters, suitable to consistently represent a widespread number of possible bulge configurations, are defined and accordingly generated. The concept is showcased taking into account the steady flow field at systolic peak conditions, using ANSYS®Fluent®and its ROM environment for CFD and ROM calculations respectively, and the RBF Morph^TM software for shape parametrization.

  • computational fluid dynamic study for ataa hemodynamics an integrated image based and radial basis functions mesh morphing approach
    Journal of Biomechanical Engineering-transactions of The Asme, 2018
    Co-Authors: Katia Capellini, Emanuele Vignali, Emiliano Costa, Emanuele Gasparotti, Marco Evangelos Biancolini, Luigi Landini, Vincenzo Positano, Simona Celi
    Abstract:

    : We present a novel framework for the fluid dynamics analysis of healthy subjects and patients affected by ascending Thoracic Aorta Aneurysm (aTAA). Our aim is to obtain indications about the effect of a bulge on the hemodynamic environment at different enlargements. 3D surface models defined from healthy subjects and patients with aTAA, selected for surgical repair, were generated. A representative shape model for both healthy and pathological groups has been identified. A morphing technique based on radial basis functions (RBF) was applied to mould the shape relative to healthy patient into the representative shape of aTAA dataset to enable the parametric simulation of the aTAA formation. CFD simulations were performed by means of a finite volume solver using the mean boundary conditions obtained from three-dimensional (PC-MRI) acquisition. Blood flow helicity and flow descriptors were assessed for all the investigated models. The feasibility of the proposed integrated approach of RBF morphing technique and CFD simulation for aTAA was demonstrated. Significant hemodynamic changes appear at the 60% of the bulge progression. An impingement of the flow toward the bulge was observed by analyzing the normalized flow eccentricity index.