The future of quantitative pupillometry in health and disease

Excerpt

The amount of light that reaches the retina is regulated through the synergistic constriction and dilation of the pupil in response to the amount of ambient light in a given environment. The pupillary light reflex (PLR) describes the rapid, immediate constriction of the pupil that is evoked by flashing a short-duration light stimulus directly into a person’s eye, followed by rapid dilation following stimulus offset. Although the PLR can be observed by flashing a simple penlight, quantitative pupillometry systems allow for a more objective measurement of the response as well as better stimulus control. Further, quantitative pupillometry systems compute several other parameters that may reflect individual variation in the PLR, including latency and velocity of the response. …