Endovascular image-guided interventions (EIGI) involve navigation of a catheter through the vasculature followed by application of treatment at the site of anomaly using live 2D projection images for guidance. 3D images acquired prior to EIGI are used to quantify the vascular anomaly and plan the intervention. If fused with the information of live 2D images they can also facilitate navigation and treatment. For this purpose 3D-2D image registration is required. Although several 3D-2D registration methods for EIGI achieve registration accuracy below 1 mm, their clinical application is still limited by insufficient robustness or reliability. In this paper, we propose a 3D-2D registration method based on matching a 3D vasculature model to intensity gradients of live 2D images. To objectively validate 3D-2D registration methods, we acquired a clinical image database of 10 patients undergoing cerebral EIGI and established "gold standard" registrations by aligning fiducial markers in 3D and 2D images. The proposed method had mean registration accuracy below 0.65 mm, which was comparable to tested state-of-the-art methods, and execution time below 1 s. With the highest rate of successful registrations and the highest capture range the proposed method was the most robust and thus a good candidate for application in EIGI.

Because the tested methods perform simultaneous C-arm calibration and 3D-2D registration based solely on anatomical information, they have a high potential for automation and thus for an immediate integration into current interventional workflow. One of the authors' main contributions is also comprehensive and representative validation performed under realistic conditions as encountered during cerebral EIGI.

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The research in this paper focuses on the perception of institutions as the drivers of economic growth. A critical presentation of the views of classical, neoclassical and endogenous growth theorists on this issue is given. It was pointed out that the classical economic theory presented in the works of Smith, Ricardo and Malthus implies the importance of the existence of an appropriate institutional framework for initiating economic growth. The attitude of the classics is that the state can stimulate economic growth through various measures aimed at building quality institutions. On the contrary, the neoclassical growth theory has completely neglected the treatment of institutions in the analysis of economic growth. Institutions as drivers of economic growth are not taken into account in the Robert Solow’s model. However, broadly speaking, it can be assumed that the impact of institutions on the initiation of economic growth is embedded in the category of residuals and the premise of the existence of a high substitution of production factors. But, this fact, even from a distance, does not call into question the general conclusion about the unacceptable neglect of the importance of institutions in explaining the physiology of economic growth by neoclassicists. Finally, the paper emphasizes the fact that only with the emergence of an endogenous growth theory, the question of the underdevelopment of the institutions as an important model of slow economic progress of certain countries is explored. Unfortunately, the developed theoretical models of growth, which include institutions as a full concept, still do not exist in the endogenous theory of economic development.