A model for evaluating the ocular contusion injury potential of propelled objects

Area of Science:

• Ophthalmology
• Biomechanics
• Injury Biomechanics

Background:

• Ocular contusion is a significant concern, particularly from projectile impacts.
• Existing literature widely advocates eyeball expansion as the primary injury mechanism.
• Understanding the biomechanics of ocular trauma is crucial for developing safety standards.

Purpose of the Study:

• To develop a mathematical model for predicting maximum contact force during ocular contusion.
• To relate this force to the eyeball expansion injury mechanism.
• To assess the ocular injury hazard potential of projectile toys.

Main Methods:

• Analysis of existing experimental data on ocular contusion.
• Development of a simple mathematical model incorporating contact force and loading rate.
• Dimensional analysis to generate ocular injury tolerance curves.
• Validation against ophthalmologists' subjective opinions.

Main Results:

• The model successfully predicted maximum contact force related to eyeball expansion.
• The model accounted for the effect of loading rate on injury.
• Generated tolerance curves showed good agreement with experimental data and expert opinion.
• Assessment of projectile toys revealed a spectrum of injury potential, from safe to hazardous.

Conclusions:

• The developed mathematical model provides a quantitative method for assessing ocular contusion risk.
• Eyeball expansion is a key factor in projectile-induced ocular injury.
• The model can effectively evaluate the safety of consumer products like projectile toys, identifying potential hazards.