Ocular biomechanics during improvised explosive device blast: A computational study using eye-specific models

Background: Eye injuries comprise 10-13% of civilian improvised explosive device (IED) injuries. The bomb blast wave induces a normal and shear forces on the tissues, causing a large acute IOP eleva-tion. This study calculated the biomechanical stresses and strains in the eye due to IED explosion via eye-specific fluid-structure interaction (FSI) models.Methods: Blast occurred at 2, 3, and 4 m from the front and side of the victim and the weights of the IED were 1 and 2 kg. The ground was covered with the deformable soil to mimic the realistic IED explosion condition and reflect the blast wave.Results: The IOP elevation of-6,0 0 0-48,0 0 0 mmHg was observed in the eyes while the highest IOP was occurred with the IED weight and distance of 2 kg and 2 m (front) and the lowest was occurred with the IED weight and distance of 1 kg and 4 m (side). Our findings suggest the importance of the victim location and orientation concerning the blast wave when it comes to ocular injury assessment. IOP elevation of-2900 and-2700 mmHg were observed in-1.6 ms after the blast for the IEDS weight of 2 kg and a victim distance of 2 m in front and side blasts, respectively, in consistence with the literature. Nonetheless, IOPs were considerably higher after-1.6 ms due to the merging of the bomb blast wave and its reflection off the ground.Conclusions: The stresses and strains were highest for the frontal blast. Both side and frontal blasts caused higher stresses and strains at the rectus muscle insertions where the sclera is thinnest and prone to rupture. Blast angle has no considerable role in the resultant IOP. Front blast with a heavier IED re-sulted a higher stresses and deformations in the eye connective tissues compared to the side blast.(c) 2022 Elsevier Ltd. All rights reserved.

Automated summary

Eye injuries caused by explosive devices are significant, and the blast wave can result in elevated intraocular pressure. This study utilized eye-specific models to calculate the biomechanical stresses and strains in the eye caused by IED explosions.