Effect of Fluid Flow Direction on Intravitreal Injections of Drugs into Eye

Abstract

The amount of drug in the eye depends on various factors such as genetics, layers structure, temperature distribution, and aqueous humor flow field. The heat transfer, fluid flow field, and drug delivery in the eye are numerically simulated using a three-dimensional model. The results are compared with experimental data on human and rabbit eyes. The effect of ambient temperature on the flow field in standing and supine positions was investigated. Then the transfer of drug concentration by intravitreal injection method was simulated using the obtained flow field. The results showed that the temperature distribution and the position of the eye relative to the direction of gravity have a significant role in the process of concentration transfer in the anterior segment of the eye. The results showed that in an intravitreal injection method, the drug has a significant concentration in the posterior part of the eye. In the intravitreal injection method with the injection of 1.25 mg of the drug, the maximum concentration in the vitreous humor is 1575.5 μg/ml, and the drug vanishes into the eye after 30 days. In this case, the maximum drug concentration in the aqueous humor is 30.16 μg/ml, which occurs after 1.5 days. © 2023 Taylor & Francis Group, LLC.