Uncorrected presbyopia: a risk factor for ischaemic retinal disease?
Adults over ~50 years of age are Presbyopic: they have lost the ability to change the eye’s focus and so near objects are out of focus without reading glasses. Millions of older people in the developing world have no access to spectacles, so their presbyopia is uncorrected and images of near objects are constantly out of focus on the retina.
This study of 37 presbyopic subjects shows that 2 dioptres of retinal defocus causes the vascular bed of the retina – the choroid – to become thinner. Choroidal thinning is linked to reduced choroidal blood perfusion. Therefore, in a normal environment, uncorrected presbyopia and its associated retinal defocus at near, would cause choroidal thinning and reduced blood perfusion and is therefore a likely risk factor for ischaemic retinal disease.