Browsing by Author "Sotelo Parraguez, Julio Andrés"
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- Item3D axial and circumferential wall shear stress from 4D flow MRI data using a finite element method and a laplacian approach(2018) Sotelo Parraguez, Julio Andrés; Dux-Santoy, Lydia; Guala, Andrea; Rodriguez-Palomares, Jose; Evangelista, Arturo; Sing-Long C., Carlos A.; Urbina, Jesus; Mura Mardones, Joaquín Alejandro; Hurtado Sepúlveda, Daniel; Uribe Arancibia, Sergio A.
- Item3D Printed Models for Planning Endovascular Stenting in Transverse Aortic Arch Hypoplasia(2015) Valverde, Israel; Gómez, Gorka; Coserria, Jose Felix; Suarez Mejias, Cristina; Uribe Arancibia, Sergio A.; Sotelo Parraguez, Julio Andrés; Velasco, Maria Nieves; De Soto, Jose Santos; Hosseinpour, Amir Reza; Gómez Cia, Tomas
- Item3D quantification of hemodynamics parameters of pulmonary artery and aorta using finite-element interpolations in 4D flow MR data(2015) Sotelo Parraguez, Julio Andrés; Urbina, Jesus.; Valverde, Israel.; Tejos Núñez, Cristián Andrés; Irarrázaval Mena, Pablo; Hurtado Sepúlveda, Daniel; Uribe Arancibia, Sergio A.
- Item3D Quantification of Wall Shear Stress and Oscillatory Shear Index Using a Finite-Element Method in 3D CINE PC-MRI Data of the Thoracic Aorta(2016) Sotelo Parraguez, Julio Andrés; Urbina, Jesus; Valverde, Israel; Tejos Nunez, Cristian Andres; Irarrázaval Mena, Pablo; Andia Kohnenkampf, Marcelo Edgardo; Uribe Arancibia, Sergio A.; Hurtado Sepúlveda, DanielSeveral 2D methods have been proposed to estimate WSS and OSI from PC-MRI, neglecting the longitudinal velocity gradients that typically arise in cardiovascular flow, particularly on vessel geometries whose cross section and centerline orientation strongly vary in the axial direction. Thus, the contribution of longitudinal velocity gradients remains understudied. In this work, we propose a 3D finite-element method for the quantification of WSS and OSI from 3D-CINE PC-MRI that accounts for both in-plane and longitudinal velocity gradients. We demonstrate the convergence and robustness of the method on cylindrical geometries using a synthetic phantom based on the Poiseuille flow equation. We also show that, in the presence of noise, the method is both stable and accurate. Using computational fluid dynamics simulations, we show that the proposed 3D method results in more accurate WSS estimates than those obtained from a 2D analysis not considering out-of-plane velocity gradients. Further, we conclude that for irregular geometries the accurate prediction of WSS requires the consideration of longitudinal gradients in the velocity field. Additionally, we compute 3D maps of WSS and OSI for 3D-CINE PC-MRI data sets from an aortic phantom and sixteen healthy volunteers and two patients. The OSI values show a greater dispersion than WSS, which is strongly dependent on the PC-MRI resolution. We envision that the proposed 3D method will improve the estimation of WSS and OSI from 3D-CINE PC-MRI images, allowing for more accurate estimates in vessels with pathologies that induce high longitudinal velocity gradients, such as coarctations and aneurisms.
- Item3D quantification of wall shear stress using finite-element interpolations from 4D flow MR data in the Thoracic Aorta(2014) Sotelo Parraguez, Julio Andrés; Urbina, Jesus.; Tejos Núñez, Cristián Andrés; Valverde, Israel.; Hurtado Sepúlveda, Daniel; Uribe Arancibia, Sergio A.
- ItemA realistic MR compatible aortic phantom to validate hemodynamic parameters from MRI data: aortic coarctation patients comparison using catheterization(2015) Urbina, Jesus; Sotelo Parraguez, Julio Andrés; Tejos Núñez, Cristián Andrés; Irarrázaval Mena, Pablo; Andía Kohnenkampf, Marcelo Edgardo; Razavi, Reza; Valverde, Israel; Uribe Arancibia, Sergio A.
- ItemAssessment of normal flow patterns in the pulmonary circulation by using 4D magnetic resonance velocity mapping(2013) Bächler, Pablo; Pinochet, Natalia; Sotelo Parraguez, Julio Andrés; Crelier, Gérard; Irarrázaval Mena, Pablo; Tejos Núñez, Cristián Andrés; Uribe Arancibia, Sergio A.
- ItemEnhancing the Velocity Data From 4D Flow MR Images by Reducing its Divergence(2016) Mura, J.; Pino, A. M.; Sotelo Parraguez, Julio Andrés; Valverde, I.; Tejos Núñez, Cristián Andrés; Andía Kohnenkampf, Marcelo Edgardo; Irarrázaval Mena, Pablo; Uribe Arancibia, Sergio A.
- ItemFalse lumen pressure estimation in type B aortic dissection using 4D flow cardiovascular magnetic resonance: comparisons with aortic growth(2021) Marlevi, David; Sotelo Parraguez, Julio Andrés; Grogan Kaylor, Andrew; Ahmed, Yunus; Uribe Arancibia, Sergio A.; Patel, Himanshu J.; Edelman, Elazer R.; Nordsletten, David A.; Burris, Nicholas S.Abstract Background Chronic type B aortic dissection (TBAD) is associated with poor long-term outcome, and accurate risk stratification tools remain lacking. Pressurization of the false lumen (FL) has been recognized as central in promoting aortic growth. Several surrogate imaging-based metrics have been proposed to assess FL hemodynamics; however, their relationship to enlarging aortic dimensions remains unclear. We investigated the association between aortic growth and three cardiovascular magnetic resonance (CMR)-derived metrics of FL pressurization: false lumen ejection fraction (FLEF), maximum systolic deceleration rate (MSDR), and FL relative pressure (FL ΔPmax). Methods CMR/CMR angiography was performed in 12 patients with chronic dissection of the descending thoracoabdominal aorta, including contrast-enhanced CMR angiography and time-resolved three-dimensional phase-contrast CMR (4D Flow CMR). Aortic growth rate was calculated as the change in maximal aortic diameter between baseline and follow-up imaging studies over the time interval, with patients categorized as having either ‘stable’ (< 3 mm/year) or ‘enlarging’ (≥ 3 mm/year) growth. Three metrics relating to FL pressurization were defined as: (1) FLEF: the ratio between retrograde and antegrade flow at the TBAD entry tear, (2) MSDR: the absolute difference between maximum and minimum systolic acceleration in the proximal FL, and (3) FL ΔPmax: the difference in absolute pressure between aortic root and distal FL. Results FLEF was higher in enlarging TBAD (49.0 ± 17.9% vs. 10.0 ± 11.9%, p = 0.002), whereas FL ΔPmax was lower (32.2 ± 10.8 vs. 57.2 ± 12.5 mmHg/m, p = 0.017). MSDR and conventional anatomic variables did not differ significantly between groups. FLEF showed positive (r = 0.78, p = 0.003) correlation with aortic growth rate whereas FL ΔPmax showed negative correlation (r = − 0.64, p = 0.026). FLEF and FL ΔPmax remained as independent predictors of aortic growth rate after adjusting for baseline aortic diameter. Conclusion Comparative analysis of three 4D flow CMR metrics of TBAD FL pressurization demonstrated that those that focusing on retrograde flow (FLEF) and relative pressure (FL ΔPmax) independently correlated with growth and differentiated patients with enlarging and stable descending aortic dissections. These results emphasize the highly variable nature of aortic hemodynamics in TBAD patients, and suggest that 4D Flow CMR derived metrics of FL pressurization may be useful to separate patients at highest and lowest risk for progressive aortic growth and complications.
- ItemHARP-I: A Harmonic Phase Interpolation Method for the Estimation of Motion From Tagged MR Images(IEEE, 2021) Mella Lobos, Hernán Arturo; Mura Mardones, Joaquín Alejandro; Wang, Hui; Taylor, Michael D.; Chabiniok, Radomir; Tintera, Jaroslav; Sotelo Parraguez, Julio Andrés; Uribe Arancibia, Sergio A.We proposed a novel method called HARP-I, which enhances the estimation of motion from tagged Magnetic Resonance Imaging (MRI). The harmonic phase of the images is unwrapped and treated as noisy measurements of reference coordinates on a deformed domain, obtaining motion with high accuracy using Radial Basis Functions interpolations. Results were compared against Shortest Path HARP Refinement (SP-HR) and Sine-wave Modeling (SinMod), two harmonic image-based techniques for motion estimation from tagged images. HARP-I showed a favorable similarity with both methods under noise-free conditions, whereas a more robust performance was found in the presence of noise. Cardiac strain was better estimated using HARP-I at almost any motion level, giving strain maps with less artifacts. Additionally, HARP-I showed better temporal consistency as a new method was developed to fix phase jumps between frames. In conclusion, HARP-I showed to be a robust method for the estimation of motion and strain under ideal and non-ideal conditions.
- ItemIntrahepatic portal vein blood volume estimated by non-contrast magnetic resonance imaging for the assessment of portal hypertension(2015) Aguirre Reyes, Daniel F.; Sotelo Parraguez, Julio Andrés; Arab Verdugo, Juan Pablo; Arrese Jiménez, Marco; Tejos, Rodrigo; Irarrázaval Mena, Pablo; Tejos Núñez, Cristián Andrés; Uribe Arancibia, Sergio A.; Andía Kohnenkampf, Marcelo Edgardo
- ItemLow and Oscillatory Wall Shear Stress Is Not Related to Aortic Dilation in Patients With Bicuspid Aortic Valve A Time-Resolved 3-Dimensional Phase-Contrast Magnetic Resonance Imaging Study(2020) Dux-Santoy, L; Guala, A; Sotelo Parraguez, Julio Andrés; Uribe Arancibia, Sergio A.; Teixido-Tura, G; Ruiz-Munoz, A; Hurtado Sepúlveda, Daniel; Valente, F; Galian-Gay, L; Gutierrez, L; Gonzalez-Alujas, T; Johnson, KM; Wieben, O; Ferreira, I; Evangelista, A; Rodriguez-Palomares, JF
- ItemNormal values of wall shear stress in the pulmonary artery from 4D flow data(2012) Sotelo Parraguez, Julio Andrés; Bächler, Pablo.; Chabert, Steren.; Hurtado Sepúlveda, Daniel; Irarrázaval Mena, Pablo; Tejos Núñez, Cristián Andrés; Uribe Arancibia, Sergio A.
- ItemPressure gradient prediction in aortic coarctation using a computational-fluid-dynamics model: validation against invasive pressure catheterization at rest and pharmacological stress(2015) Sotelo Parraguez, Julio Andrés; Valverde, Israel.; Beerbaum, Philipp B.; Greil, Gerald F.; Schaeffter, Tobias.; Razavi, Reza.; Hurtado Sepúlveda, Daniel; Uribe Arancibia, Sergio A.; Figueroa, Carlos A.
- ItemQuantification of pulmonary regurgitation in patients with repaired Tetralogy of Fallot by 2D phase-contrast MRI: Differences between the standard method of velocity averaging and a pixel-wise analysis(2017) Sotelo Parraguez, Julio Andrés; Bächler, Pablo; Urbina, Jesús; Crelier, Gerard; Toro Rosas, Lida Elba Graciela; Ferreiro, Myriam; Valverde, Israel; Andía Kohnenkampf, Marcelo Edgardo; Tejos Núñez, Cristián Andrés; Irarrázaval Mena, Pablo; Uribe Arancibia, Sergio A.
- ItemQuantification of wall shear stress using a finite-element method in multidimensional phase-contrast MR data of the thoracic aorta(2015) Sotelo Parraguez, Julio Andrés; Urbina, Jesús; Valverde, Israel; Tejos Núñez, Cristián Andrés; Irarrázaval Mena, Pablo; Hurtado Sepúlveda, Daniel; Uribe Arancibia, Sergio A.
- ItemQuantification of wall shear stress using finite-element interpolations in multidimensional phase contrast MR data of the thoracic aorta(2014) Sotelo Parraguez, Julio Andrés; Urbina, Jesús.; Ortíz, Ernesto.; Tejos Núñez, Cristián Andrés; Valverde, Israel.; Hurtado Sepúlveda, Daniel; Uribe Arancibia, Sergio A.
- ItemRealistic aortic phantom to study hemodynamics using MRI and cardiac catheterization in normal and aortic coarctation conditions(2016) Urbina, Jesús; Sotelo Parraguez, Julio Andrés; Springmüller P., Daniel; Montalba, Cristian; Letelier, Karis; Tejos Núñez, Cristián Andrés; Irarrázaval Mena, Pablo; Andía Kohnenkampf, Marcelo Edgardo; Razavi, Reza; Valverde, Israel; Uribe Arancibia, Sergio A.
- ItemThree-dimensional quantification of vorticity and helicity from 3D cine PC-MRI using finite-element interpolations(2018) Sotelo Parraguez, Julio Andrés; Urbina, Jesús; Valverde, Israel; Mura Mardones, Joaquín Alejandro; Tejos Núñez, Cristián Andrés; Irarrázaval Mena, Pablo; Andía Kohnenkampf, Marcelo Edgardo; Hurtado Sepúlveda, Daniel; Uribe Arancibia, Sergio A.
- ItemVariability of 4D flow parameters when subjected to changes in MRI acquisition parameters using a realistic thoracic aortic phantom(2018) Montalba, Cristian; Urbina, Jesus; Sotelo Parraguez, Julio Andrés; Andía Kohnenkampf, Marcelo Edgardo; Tejos Núñez, Cristián Andrés; Irarrázaval Mena, Pablo; Hurtado Sepúlveda, Daniel; Valverde, Israel; Uribe Arancibia, Sergio A.