Sarah Kochik and Nevin El-Nimri
Monday, October 22, 2018
11:10 am - 12:30 pm
489 Minor Hall
Manipulating Intraocular Pressure as a Novel Avenue for Controlling Myopia Progression
Myopia (near-sightedness) results from progressive, excessive eye enlargement and is associated with blinding complications. It has become a significant public health concern, reaching epidemic levels in some parts of the world. The eye is like a balloon, with pressure inside the eye (IOP) exerting a stretching influence on the outer (scleral) wall of the eye and the lamina cribrosa, a sieve-like structure through which nerves relaying visual information from the eye’s seeing layer (retina) pass to the brain. The specific aim is to determine, using the guinea pig as a myopia model, whether IOP lowering drugs used in glaucoma patients can also be used to slow eye enlargement as a myopia treatment. Guinea pigs wore white plastic diffusers over one eye, as an established method for inducing myopia, from 2 weeks of age for 10 weeks. The same eyes of half of the animals were treated with IOP-lowering drugs and the others with artificial tears. Animals underwent weekly eye examinations that included measurements of eye length, refractive error, and IOP. We hope this will lead to new treatment options for patients with progressive myopia.
Among optical treatments for myopia, orthokeratology lenses have demonstrated consistent reduced myopia progression compared to spectacles and single vision contact lenses. It has been suggested that having a smaller treated area (and larger area of peripheral defocus) may lead to improved myopia control. This pilot study seeks to compare the standard CRT lens, which carries a 6mm optic zone size to a novel lens design (the “test lens”) with a 5mm optic zone size. We had expected that visual performance would be negatively influenced by wearing a lens with such a small treatment zone. However, while unaided visual acuity was slightly better for the standard 6mm lenses, other measures of optical quality were actually inferior, including refraction, AULCSF, and subjective impression of vision.