Numerical simulation for unsteady motions of the human vitreous humor as a viscoelastic substance in linear and non-linear regimes

Modarreszadeh, Amir; Abouali, Omid

doi:10.1016/j.jnnfm.2013.12.001

Cited by 21 publications

(12 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Their work was later extended by Meskauskas et al [ 13 ], who showed that resonant excitation of vitreous motion can possibly occur during normal eye rotation conditions. Modarreszadeh and Abouali [ 14 ] recently proposed a fully numerical model of vitreous motion accounting for a realistic geometry of the vitreous chamber.…”

Section: Introductionmentioning

confidence: 99%

An experimental model of vitreous motion induced by eye rotations

et al. 2015

View full text Add to dashboard Cite

BackgroundDuring eye rotations the vitreous humour moves with respect to the eye globe. This relative motion has been suggested to possibly have an important role in inducing degradation of the gel structure, which might lead to vitreous liquefaction and/or posterior vitreous detachment. Aim of the present work is to study the characteristics of vitreous motion induced by eye rotations.MethodsWe use an experimental setup, consisting of a Perspex model of the vitreous chamber that, for simplicity, is taken to have a spherical shape. The model is filled with an artificial vitreous humour, prepared as a solution of agar powder and hyaluronic acid sodium salt in deionised water, which has viscoelastic mechanical properties similar to those of the real vitreous. The model rotates about an axis passing through the centre of the sphere and velocity measurements are taken on the equatorial plane orthogonal to the axis of rotation, using an optical technique.ResultsThe results show that fluid viscoelasticity has a strong influence on flow characteristics. In particular, at certain frequencies of oscillation of the eye model, fluid motion can be resonantly excited. This means that fluid velocity within the domain can be significantly larger than that of the wall.ConclusionsThe frequencies for which resonant excitation occurs are within the range of possible eye rotations frequencies. Therefore, the present results suggest that resonant excitation of vitreous motion is likely to occur in practice. This, in turn, implies that eye rotations produce large stresses on the retina and within the vitreous that may contribute to the disruption of the vitreous gel structure. The present results also have implications for the choice of the ideal properties for vitreous substitute fluids.

show abstract

Section: Introductionmentioning

confidence: 99%

An experimental model of vitreous motion induced by eye rotations

et al. 2015

View full text Add to dashboard Cite

show abstract

“…6. [23]. The VH was modeled with a 2-mode Giesekus model (see [23]), based on the rheological characteristics presented by [7], and a density ρ = 1000 kg/m 3 was used.…”

Section: Computational Meshmentioning

confidence: 99%

“…Those results were later corroborated by Isakova et al [21], who predicted the same trend using an analytical approach, and also by Bonfiglio et al [22] who also obtained similar results based on an experimental study. Modarreszadeh and Abouali [23] focused on providing a reliable numerical procedure for the study of VH as a viscoelastic substance and under oscillatory movements. The open-source software OpenFOAM ® was used and the viscoelastic solver developed by Favero et al [24] was adapted to handle dynamic meshes.…”

Section: Introductionmentioning

confidence: 99%

“…simplified eye geometry, assumption of VH as a Newtonian fluid, considering sinusoidal movements) that may lead to significant differences in the flow behaviour when compared with the real VH in the eye. Additionally, to the best of our knowledge, there are no numerical studies that consider the viscoelastic behaviour of the VH liquid phase, as it is usually simulated as a Newtonian fluid [25,19,23].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Flow dynamics of vitreous humour during saccadic eye movements

Silva

Pimenta

Alves

et al. 2020

Journal of the Mechanical Behavior of Biomedical Materials

View full text Add to dashboard Cite

show abstract

“…Such a method has been used in various applications, such as cardiac valves [8] and animal locomotion [9], but this is the first time, to the authors knowledge, it has been used in the context of retinal detachment modelling. Previous works regarding the retina include calculating the shear stress on the retinal surface [10,11,12,13,14,15], gas diffusion in the vitreous cavity [16], silicone oil usage [17,18], retinal tractions [19] and peeling of membranes from the retinal surface [17,20], just to mention a few. In order to study the tendency of the retina to further detach from the underlying choroid, due to the combined actions of the forces and torque at the attachment point(s) arising from the interaction between the detached retina and the surrounding fluid, we borrow a simple model from geotechnics of a structure on an elastic foundation [21].…”

Section: Introductionmentioning

confidence: 99%