title: Non-invasive pressure difference estimation from PC-MRI using the work-energy equation.
abstract: Pressure difference is an accepted clinical biomarker for cardiovascular disease conditions such as aortic coarctation. Currently, measurements of pressure differences in the clinic rely on invasive techniques (catheterization), prompting development of non-invasive estimates based on blood flow. In this work, we propose a non-invasive estimation procedure deriving pressure difference from the work-energy equation for a Newtonian fluid. Spatial and temporal convergence is demonstrated on in silico Phase Contrast Magnetic Resonance Image (PC-MRI) phantoms with steady and transient flow fields. The method is also tested on an image dataset generated in silico from a 3D patient-specific Computational Fluid Dynamics (CFD) simulation and finally evaluated on a cohort of 9 subjects. The performance is compared to existing approaches based on steady and unsteady Bernoulli formulations as well as the pressure Poisson equation. The new technique shows good accuracy, robustness to noise, and robustness to the image segmentation process, illustrating the potential of this approach for non-invasive pressure difference estimation.
authors.affiliation: King's College London, Department of Biomedical Engineering and Imaging Sciences, St. Thomas' Hospital, 4th floor Lambeth Wing, The Rayne Institute, London SE1 7EH, United Kingdom. Electronic address: fabrizio.donati@kcl.ac.uk.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Donati
authors.affiliation: University of Michigan, North Campus Research Complex, 2800 Plymouth Road, Ann Arbor, MI 48105, United States. Electronic address: figueroc@med.umich.edu.
authors.forename: C Alberto
authors.initials: CA
authors.lastname: Figueroa
authors.affiliation: King's College London, Department of Biomedical Engineering and Imaging Sciences, St. Thomas' Hospital, 4th floor Lambeth Wing, The Rayne Institute, London SE1 7EH, United Kingdom; University of Auckland, Engineering School Block 1, Level 5, 20 Symonds St, Auckland 101, New Zealand. Electronic address: np.smith@auckland.ac.nz.
authors.forename: Nicolas P
authors.initials: NP
authors.lastname: Smith
authors.affiliation: King's College London, Department of Biomedical Engineering and Imaging Sciences, St. Thomas' Hospital, 4th floor Lambeth Wing, The Rayne Institute, London SE1 7EH, United Kingdom; University of Oxford, Department of Computer Science, Wolfson Building, Parks Road, Oxford OX1 3QD, United Kingdom. Electronic address: pablo.lamata@kcl.ac.uk.
authors.forename: Pablo
authors.initials: P
authors.lastname: Lamata
authors.affiliation: King's College London, Department of Biomedical Engineering and Imaging Sciences, St. Thomas' Hospital, 4th floor Lambeth Wing, The Rayne Institute, London SE1 7EH, United Kingdom. Electronic address: david.nordsletten@gmail.com.
authors.forename: David A
authors.initials: DA
authors.lastname: Nordsletten
mesh_terms: D001011:Aorta / Q000033:anatomy & histology / Q000502:physiology*; D062186:Arterial Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods*; D003198:Computer Simulation; D004734:Energy Metabolism / Q000502:physiology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D044085:Microfluidics / Q000379:methods; D008955:Models, Cardiovascular; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: 4D flow; Aortic flow; PC-MRI; Pressure differences estimation; Work-energy equation