Summers, Jody A. (HSC)
University of North Dakota
Myopia is the most common of all ocular problems, affecting 25 percent of the US adult population. The most common structural abnormality associated with myopia is excessive lengthening of the posterior segment of the ocular globe (axial myopia). Generally, myopia increases just before and during puberty and then stabilizes. If axial elongation fails to stabilize, an individual has an increased risk for a number of severe ocular diseases including glaucoma, retinal detachment and blindness. While it is clear that changes in the shape of the sclera produce myopia, the basis for this shape change is largely unknown. The sclera is a connective tissue, consisting of interwoven collagen fibrils in close association with proteoglycans, that provides the structural framework that defines the shape and therefore the axial length of the eye. Past work by our lab and others has clearly demonstrated that the sclera is not a static container of the eye, but rather is a dynamic tissue, capable of altering extracellular matrix composition and its biomechanical properties in response to changes in the visual environment to regulate ocular size and refraction. The mechanism by which this visually-guided scleral remodeling is regulated is largely unknown. We hypothesize that scleral growth and remodelling is regulated by the synthesis and release of soluble factors from the retina, RPE and/or choroid in response to changes in the visual environment which result in changes in ocular size and refraction. Our lab is employing a variety of in vivo and in vitro strategies aimed at identifing such scleral growth regulators. Ultimately, it is hoped that our research will aid in the development of therapies to slow or prevent the progession of myopia in children.