Abstract
Abstract: :
Purpose: To determine changes induced in mechanical stress in retina by a simulated peripheral laser photocoaggulation. Methods: A shell model for retina was analyzed using finite-element analysis program to calculate the mechanical stress in retina due to intraocular pressure while constrained at the ora serrata and at the optic disk. The analysis was repeated with an additional constraint in the form of a ring around the arcades simulating the effect of deep peripheral laser photocoaggulation. Results: In a normal retina, the location of maximal tensile stress is found in the macula. By constraining retina around the arcades the magnitude of stress in the macula decreases, and the location of maximal stress is noted to move anterior to the ring of fixation. Conclusions: Previously, we presented the hypothesis that age-related macular degeneration may be associated with cyclical variation in mechanical stress in the posterior pole. We, now, suggest that laser photocoaggulation or other means of mechanical fixation of retina outside the arcades can lower the stress in the macula, and hence may reduce the risk of AMD.
Keywords: age-related macular degeneration • laser • Bruch's membrane