Paul Roberts, University of Birmingham, "Mathematical models to elucidate the mechanisms underlying sight loss"

Paul Roberts, Centre for Systems Modelling and Quantitative Biomedicine at the University of Birmingham, will discuss: Mathematical models to elucidate the mechanisms underlying sight loss
The retina is a tissue layer at the back of the eye that uses photoreceptor cells to detect light. Photoreceptors can be characterised as either rods or cones. Rods provide achromatic vision under low light conditions, while cones provide high-acuity colour vision under well-lit conditions. The term retinitis pigmentosa (RP) refers to a range of genetically mediated retinal diseases that cause the loss of photoreceptors and hence visual function. RP leads to a patchy degeneration of photoreceptors and typically directly affects the rods (which express a mutant gene), but not the cones. During the course of the disease, degenerate patches spread and the cones also begin to degenerate. The cause underlying these phenomena is currently unknown; however, several key mechanisms have been hypothesised, including oxygen toxicity, trophic factor depletion and the release of toxic substances by dying cells. Here we present mathematical models, formulated as systems of PDEs, to investigate the trophic factor hypothesis. Using a combination of numerical simulations and mathematical analysis, we determine the geographic variation in retinal susceptibility to degeneration, predict the effects of various clinically-relevant treatment strategies, predict spatio-temporal patterns of degeneration and solve an inverse problem to determine the conditions under which in vivo spatio-temporal patterns of degeneration are replicated by our models.