title: Rôle of contrast media viscosity in altering vessel wall shear stress and relation to the risk of contrast extravasations.
abstract: Iodinated contrast media (CM) are the most commonly used injectables in radiology today. A range of different media are commercially available, combining various physical and chemical characteristics (ionic state, osmolality, viscosity) and thus exhibiting distinct in vivo behaviour and safety profiles. In this paper, numerical simulations of blood flow with contrast media were conducted to investigate the effects of contrast viscosity on generated vessel wall shear stress and vessel wall pressure to elucidate any possible relation to extravasations. Five different types of contrast for Iodine fluxes ranging at 1.5-2.2gI/s were modelled through 18G and 20G cannulae placed in an ideal vein at two different orientation angles. Results demonstrate that the least viscous contrast media generate the least maximum wall shear stress as well as the lowest total pressure for the same flow rate. This supports the empirical clinical observations and hypothesis that more viscous contrast media are responsible for a higher percentage of contrast extravasations. In addition, results support the clinical hypothesis that a catheter tip directed obliquely to the vein wall always produces the highest maximum wall shear stress and total pressure due to impingement of the contrast jet on the vessel wall.
authors.affiliation: Department of Diagnostic Imaging, Glasgow Royal Infirmary, Glasgow G31 2ER, UK. Electronic address: s.sakellariou@nhs.net.
authors.forename: Sophia
authors.initials: S
authors.lastname: Sakellariou
authors.affiliation: School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK.
authors.forename: Wenguang
authors.initials: W
authors.lastname: Li
authors.affiliation: School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK. Electronic address: Manosh.Paul@glasgow.ac.uk.
authors.forename: Manosh C
authors.initials: MC
authors.lastname: Paul
authors.affiliation: Department of Diagnostic Imaging, Glasgow Royal Infirmary, Glasgow G31 2ER, UK.
authors.forename: Giles
authors.initials: G
authors.lastname: Roditi
mesh_terms: D003287:Contrast Media / Q000378:metabolism*; D005119:Extravasation of Diagnostic and Therapeutic Materials; D007455:Iodine / Q000378:metabolism; D011312:Pressure; D012212:Rheology; D012306:Risk; D033081:Shear Strength; D013314:Stress, Mechanical; D014680:Veins / Q000378:metabolism*; D014783:Viscosity
chemical_list: D003287:Contrast Media; D007455:Iodine
keywords: Blood flow; Contrast media; Extravasation; Numerical modelling; Wall shear stress