Human laser retinal dose-response model

Abstract

Probabilistic risk assessment is an acceptable technique for laser hazard analysis in uncontrolled environments. Risk is a combination of probability of exposure and probability of an injury resulting from that exposure. A dose-response model quantifies the probability of injury. In the present study, we developed a human dose-response model for laser induced retinal injuries. It consists of two sub-models, one for the mean and the other for the standard deviation of the dose-response probability distribution. The model for the mean fits experimental data to a simple three-parameter expression as a function of wavelength, exposure duration, and retinal tissue type. A scaling factor converts the fit to be appropriate for exposure of humans. A new human vulnerability model, based on the diversity of relevant physical characteristics within the human population, determines the standard deviation. Since the dose-response model is specific to retinal injuries, the variables are refractive error, ocular transmittance, and retinal absorptance. A Monte Carlo simulation with probability distributions for these variables, based on age, determines the standard deviation as a function of wavelength. We present details of the dose-response model along with their application to common human populations.Probabilistic risk assessment is an acceptable technique for laser hazard analysis in uncontrolled environments. Risk is a combination of probability of exposure and probability of an injury resulting from that exposure. A dose-response model quantifies the probability of injury. In the present study, we developed a human dose-response model for laser induced retinal injuries. It consists of two sub-models, one for the mean and the other for the standard deviation of the dose-response probability distribution. The model for the mean fits experimental data to a simple three-parameter expression as a function of wavelength, exposure duration, and retinal tissue type. A scaling factor converts the fit to be appropriate for exposure of humans. A new human vulnerability model, based on the diversity of relevant physical characteristics within the human population, determines the standard deviation. Since the dose-response model is specific to retinal injuries, the variables are refractive error, ocular transmi...