Control Of Refractive Error Through Ionically Driven Fluid Movements
Funder
National Health and Medical Research Council
Funding Amount
$208,600.00
Summary
Myopia affects about half the world's population with recent studies suggesting epidemic proportions among some Asian schoolchildren though we are not seeing this in Australia. Costs associated with detection, monitoring and optical correction of low and high myopia are huge. High myopes (15% with > 6D) also have a greatly increased risk of blindness between the ages of 30 and 50 years due to secondary disorders associated with impaired fluid balance (retinal and choroidal oedema, macula oede ....Myopia affects about half the world's population with recent studies suggesting epidemic proportions among some Asian schoolchildren though we are not seeing this in Australia. Costs associated with detection, monitoring and optical correction of low and high myopia are huge. High myopes (15% with > 6D) also have a greatly increased risk of blindness between the ages of 30 and 50 years due to secondary disorders associated with impaired fluid balance (retinal and choroidal oedema, macula oedema, retinal detachment and glaucoma). Currently there is no accepted pharmaceutical treatment for myopia though our studies in chick have provided the theoretical rationale and experimental data for a potential therapy and patent. This patent is now at the PCT stage and attests that changes in the abundance of the ions of the subretinal space control fluid movements across the retina to choroid and can be modulated therapeutically by diuretics to control fluid flow and hence axial growth and myopia. This application aims to take our current knowledge about fluid control in myopic chick into a mammalian model prior to preclinical trials in monkey. We anticipate it will take 1 year to establish the feasibility of diuretic control of experimentally induced myopic refractive errors in guinea pigs and the best drug and best the dosage range. These studies will contribute to the scientific understanding and bring the proposed pharmaceutical therapy for myopia in adults and children to a point of full commercialization. We believe that the results found in chick will have significance for early and late-onset myopia in humans as it is highly likely that the same mechanisms of ocular growth regulation operate throughout life.Read moreRead less
DISSECTING THE GENETICS OF GLAUCOMA AND ITS RISK FACTORS USING A TWIN STUDY.
Funder
National Health and Medical Research Council
Funding Amount
$682,850.00
Summary
Glaucoma is one of the leading causes of blindness both in Australia (affecting 2-3% of the population) and worldwide. Glaucoma is often asymptomatic until it causes permanent loss of peripheral vision that precludes 10% of individuals with the condition from holding a driver's license. Around 50% of people with glaucoma are unaware that they have the condition; therefore better screening strategies are required. Genetic factors have been shown to contribute to glaucoma and our work has revealed ....Glaucoma is one of the leading causes of blindness both in Australia (affecting 2-3% of the population) and worldwide. Glaucoma is often asymptomatic until it causes permanent loss of peripheral vision that precludes 10% of individuals with the condition from holding a driver's license. Around 50% of people with glaucoma are unaware that they have the condition; therefore better screening strategies are required. Genetic factors have been shown to contribute to glaucoma and our work has revealed that 50% of people with glaucoma have a family history of the condition. Raised intraocular pressure (IOP) is a major contributing factor in glaucoma. Although there are some genes associated with high-pressure glaucoma, little is known about the heritability of IOP itself. Optic disc cupping is another important sign in the diagnosis and management of glaucoma, but again little is known of the inheritance of this feature. Twin studies, (comparing sets of identical twins with non-identical twins); allow us to estimate the relative contribution of genetic and environmental factors to disease states or physiological measurements. Although there have been small studies involving twins with glaucoma, it is unknown to what degree the basic parameters of glaucoma diagnosis such as IOP and optic disc characteristics are heritable. This project aims to conduct a large twin study into glaucoma and its associated ocular risk factors, including refractive error. We aim to identify genes that predispose to glaucoma, which will facilitate better screening for glaucoma in family members, and the general population, and ultimately leading to improved treatment.Read moreRead less
Therapeutic Control Of Pathological Myopia: Role Of Transforming Growth Factor-beta
Funder
National Health and Medical Research Council
Funding Amount
$312,730.00
Summary
Myopia (shortsightedness) is due to the eye being too long. It is a common refractive disorder, affecting some 25-30% of people in developed countries, and results in blurred distance vision. The optical consequences of myopia, namely blurred distance vision, are correctable with spectacles or contact lenses. However, a significant minority of individuals (3% of the Australian population) have excessively long eyes and high amounts of myopia. These enlarged eyes impose abnormal stresses on the s ....Myopia (shortsightedness) is due to the eye being too long. It is a common refractive disorder, affecting some 25-30% of people in developed countries, and results in blurred distance vision. The optical consequences of myopia, namely blurred distance vision, are correctable with spectacles or contact lenses. However, a significant minority of individuals (3% of the Australian population) have excessively long eyes and high amounts of myopia. These enlarged eyes impose abnormal stresses on the structures inside, particularly affecting the retina, which is the light sensitive part of the eye. Damage that occurs to the retina in these eyes is, at present, untreatable and irreversible and can result in blindness. Myopia is the 2nd leading cause of blindness amongst adults of working age. For the eye to grow so large, its white outer coat (the sclera) must expand without allowing any leaks of the delicate structures and fluids inside. Although the sclera gets very thin as it expands, it has been shown that this process of expansion is a biochemically active process and not due to passive stretch. Before elongation of the eye can occur the biochemical structure of the sclera must change, a complex process involving accelerated production and breakdown of the biochemical building blocks of the sclera. Previous research in our laboratory indicates that changes in structure of the sclera are associated with reduced levels of the growth-controlling protein transforming growth factor-beta (TGF-beta). The aim of this project is to supplement TGF-beta levels in the sclera in order to reverse the loss of scleral tissue, stop the development of myopia and, therefore, prevent the development of the sight-threatening pathology associated with high myopia. In addition, we will determine the most effective way to deliver a sustained dose of TGF-beta to the sclera.Read moreRead less