![]() The brain is able to correct for the shadows cast by the mostly red-blood cell populated blood vessels, but renders the white blood cells as bright white dots. In essence, the red blood cells, which form the majority of the content of the capillaries, absorb light in a different manner to the white blood cells. This is a topic that I have covered in depth in a previous Draw Curiosity episode, which I shall link down below. The blue entoptic phenomenon is the result of incorrect brain filtering of the shadows cast by the blood vessels onto the retina. People who are at high risk of retinal detachment are generally very nearsighted (-6.0 diopters or greater) in their 40-60s (when vitreous detachment generally occurs, the change in the texture of the vitreous humour causes it to shrink and unpeel from the back of the eye, occasionally taking the retina with it) or have received blows or shakes to the head (such as contact sports, car accidents, bungee jumping etc). If too much time is allowed to pass, the retina may detach at the macula point (where detailed central vision is resolved), or even detach completely, and the likelihood of having impaired vision after surgery is much higher. If caught early (within a few hours of experiencing symptoms), it can be easily reversed with routine surgery and somewhat tedious post-surgery care. If they have, and especially if there is a sudden increase in them accompanied by flashes, and perhaps a curtain drifting over your field of vision, this is a sign that your retina is detaching and is a medical emergency. Provided they haven’t appeared suddenly, they are harmless. Typically, the floaters that bother people the most are the ones that can be seen the clearest, and those are generally a fraction of a millimetre in front of the retina and there, are not a good target for lasers. The floaters they can easily target are found closer to the centre of the eye, but those are often quite blurry and interfere less with vision. The other surgical procedure that is specifically for removing floaters involves targeting the floater with a laser, although, this only works if the floaters are close to the centre of the eye. ![]() ![]() Vitrectemy is the draining of the vitreous humour of the eye, and is a good way of replacing the liquid inside the eye and thus removing floaters. Both of these procedures in fact are generally used for more serious eye surgery, such as for fixing retinal detachments and tears. There are two surgical procedures that can get rid of floaters, but given that possible side effects of both of them are retinal detachment and floaters, I wouldn’t recommend them purely for getting rid of floaters. Occasionally, some of the cells may be reabsorbed, and some claim that there are special eye exercises and movements which can help swirl the cells out of your central field of vision. Once they are there, they are there to stay. With age, it tends to shrink and may pull away from the retina, taking cells with it. People get more floaters as they get older and the internal properties of their vitreous humour change. Nearsighted people are more likely to have the most floaters due to the fact that the axial length of their eyes (ie – the distance from pupil to retina) is greater than normal or far-sighted people, which means that the content of the eye is more stretched out and at a greater risk of coming loose. Most people do actually, but some people are prone to getting more of them than others. Collagen filaments however are the most prevalent and they are also much more likely to clump together to form the long cobwebs you’ve probably seen. ![]() In my experience, viewers often come up with very insightful questions and perspectives that did not initially occur to me! Floaters What Are Floaters Made Of?įloaters are usually specks of protein, such as filaments of collagen, although occasionally there are also cells, such as photoreceptors, which have come loose from the back of the eye. I will also be keeping an eye on the comments too and updating accordingly with new questions – so feel free to ask if there is something you would like to know that isn’t already covered here. In today’s blogpost, I’m going to answer the most frequently asked questions about these visual phenomena. Thank you so much for watching my guest video on Tom Scott’s channel! You can see more of my work making science, biology and mathematics videos on my YouTube channel as well as on this blog.įor every video I make, it is my practice to write a blogpost that goes into further detail about everything that didn’t make the video’s final cut, as people generally like to find out more. ![]()
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