Age-Related Macular Degeneration

00:00 So we've looked at the arteries and veins and occlusion there. Let's talk specifically about macular degeneration. The macula, as you will recall, is the region of the posterior retina with the highest density of photoreceptors. It provides the finest visual acuity. It's how we read the printed word. It's how we recognize faces. It provides our most important central vision and in particular the fovea in the middle, that pit, has the highest density of cones.

00:30 So it's going to be really important that we maintain the normal level of density and in fine tuning of that region of the eye. Age-related macular degeneration or AMD is a process of a gradual, age-related obviously, deterioration, degeneration of that region particularly of the retina. So, it's age-related, it's found in people over the age of 50. It tends to be associated with central vision loss because in fact that's our region of highest visual acuity, so it will be noticed. Their peripheral vision will tend to be maintained. We're not losing, interestingly, rods and cones or we're not getting degeneration of the retina outside of that area. Then the actual mechanisms for all of these are not completely understood so we don't know exactly what drives this. We'll see that there are certain risk factors, but we don't understand the pathophysiology and I would throw that out as a challenge to those of you who want to become future ophthalmologists, "Take care of this, fix this, I don't wanna go blind. You're gonna have to help me." Alright. There are 2 generally recognized forms. There is the so-called dry AMD, dry acute age-related macular degeneration. It's nonexudative meaning that we're not getting leakiness of vessels and accumulation of stuff. And that's the majority of cases. And then there is wet AMD and that involves neovascularization and because the vessels are brand new, they are leaky and so there will be some accumulations of exudates, and that's 10% of cases. Neither one of these do we understand completely.