I have to credit my five year old with coming up with this week’s topic. She told me that I needed to blog about how much fiber people should eat. Clearly, little pitchers have big ears, and I am left worrying about what else I may have said aloud during depression week. When I told her that I already did that, she said, “Well, then I think you should tell people about their eyes because they are really important.” I am experiencing mixed emotions as I write this. On the one hand, I am proud that she is interested in what I do when I am not picking up her crumbs. On the other hand, I am taking the advice of a Kindergartener. Who was the mass murderer who listened to his dog? I feel a little like him.
Your eyes and their health are of utmost importance, but they are, for lack of a better word, scary to many people. I think it may be the whole window to your soul aspect. People just do not want anyone checking out their soul, through a window or otherwise. I hope this week to demystify the eyes so you can be more comfortable taking care of yours. Today, a quick little lesson on the anatomy of the eye.
1. If you think about vision, it is truly a remarkable thing and requires many working parts to make it happen. Consider a camera with an aperture that opens and closes to allow light in so the picture can be processed. The PUPIL, or the black center part of your eye, is that hole. With the right tool, you can look right through the pupil into the back of the eye. Surrounding the pupil is the IRIS or the colored part. It opens and closes to control the size of the pupil, and therefore, the amount of light that enters the eye.
2. The SCLERA is the white part of the eye including the area that you can see and then extending all the way around to the optic nerve. The CORNEA is the clear membrane that covers the pupil and the iris. The AQUEOUS HUMOR is the fluid between the cornea and the iris. It supplies nutrients to these parts of the eye.
3. The LENS is an oval shaped body that focuses the light that comes through the pupil onto the RETINA, which is made up of light sensitive cells that line the back of the eye. To continue the camera analogy, they are like the film. They record what is being seen and send it to the brain via the OPTIC NERVE. The optic nerve carries these impulses to the visual cortex which oddly is located all the way in the back of your head. Seems like a strange layout but it works. In the middle of the eyeball is the VITREOUS HUMOR. It helps to maintain the shape of the eye and it is the clear jelly-like stuff that oozes out in horror movies.
4. There are many other parts of the eye that help to protect and move the eye; that lubricate and then drain this lubrication.
5. Two things that I find especially cool about the eye. A. The blood-ocular barrier acts as a barrier between the eye and the blood that is circulating through the rest of the body. It protects the eye from infection, toxins, medications and anything else that is coursing through your veins. B. It is very resilient. I have had to convince many people that, while the eye is precious in so many ways, like all organs in a healthy body, it is capable of healing itself. Injury to the eye, while undesirable, is often not as tragic as it sounds.
I realize that anatomy is pretty dull reading, so congratulations if you made it this far. I’d love to get you all in a lab, because it is so much more impressive and interesting when you can actually hold it in your hand and cut it open. I’ll check with my five year old on how to proceed with the week, but my plan right now is to do visual loss tomorrow, infections on Thursday and serious eye illness on Friday.