By Juan Ding, OD, PhD

I discussed previously floaters in a young woman, in her case (link here) the floaters came from inflammation of her eyes, which is not a common condition. Today I want to talk about the “common” or “regular” floaters that almost everyone has or will have.

I will start with two patients I saw yesterday. A 68 year old gentleman was on the airplane to Arizona to buy a house when he noticed a big floater following him everywhere in the right eye. It had been 5 days now and wouldn’t go away. His vision was the same, but he was very concerned and came to my walk-in clinic. One of my old patients, a 75 year old woman, who saw me 6 months ago for her annual eye exam, made an urgent appointment due to a similar complaint, big floater that suddenly showed up 3 days ago. As she’s an avid reader and knitter, this floater was quite annoying with her near work.

In both patients, I diagnosed them with posterior vitreous detachment (PVD). This is a common age-related eye condition, and happens in 60% of those in their 60s, and by age 90, 90% of people would have developed PVD. This may start in one eye and eventually the other eye would develop it also.

Vitreous is the big jelly occupying the bulk of our eyeball (Figure 1A. Please pardon my poor drawing techniques). On the backside of the vitreous is the critically important tissue- retina. Vitreous and retina are normally attached to each other. It provides structural support of the eyeball and nutrients to the retina. When we were born, the vitreous is typically a single solid piece. With age, the jelly gradually forms liquefied pockets here and there with protein strands floating around. This could happen at any age. So young people also may complain about seeing floaters, but typically small floaters that don’t interfere with vision. You may notice these in a bright uniform background such as the blue sky or a white computer screen. I personally have noticed my floaters since age 8.

As the vitreous becomes ‘weaker and weaker’, it will eventually lose its contact with the retina in multiple locations. The last location that this happens is usually close to the center of our vision, near the optic nerve. The moment that it pulls away from the optic nerve, it leaves a ring-shaped residue (Figure 1B), which floats around to annoy you. Since this is much larger, you will notice it more, and many people become very symptomatic and seek medical attention. Some people also experiences brief flashes of light lasting a second or two, and this is due to the vitreous pulling on the retina.

Figure 1. Normal vitreous and posterior vitreous detachment (PVD).  A. Normal vitreous is a jelly substance that attaches to the underlying retina. B. in PVD, the vitreous detaches from the optic nerve, forming a large floater.

The whole process is actually a normal age-related phenomenon, much like wrinkled skin or gray hair. However, one caveat- when the vitreous detaches, it sometimes pulls a piece of retina with it, causing a retinal tear and even retinal detachment. Fortunately this terrible incident happens in only 7% of those experiencing PVD ¹, though some studies find this number to be 22% ². Still, if you are experiencing a new floater, you should go to your eye doctor for a dilated eye exam immediately, because if you do have a retinal tear, it needs to be fixed within 24 hours.

Further, with a new PVD, the risk of retinal tear or detachment is still high within the next 4-6 weeks, so you should have a repeated dilated eye exam in about 4-6 weeks’ time even if no new symptoms come up. At any time, if you notice new floaters, flashes or light, or have a change in vision or losing a part of your visual field, you should seek immediate medical attention.

So what do you do with a PVD? If there is no retinal tear or detachment that come with it, you can rest assured. Your brain will eventually adapt to the floater and ignore it, though this may take quite a few months. Some very few people who are bothered by floaters and find it interfering with their normal life after even 6 months, a laser can be done to break up the big floater into smaller pieces so that you won’t notice them. Alternatively a vitrectomy surgery can be done to remove the vitreous; however, the surgery is invasive and carries the risk of having infection of the whole eye or developing new retinal detachment. You should talk to your retinal specialist if you are absolutely interested in removing the floaters.

If there is indeed a retinal tear discovered, a retinal specialist will treat this immediately with a laser to seal off the tear. Or if the tear is extensive, a surgery can be done to repair the detached retina.

Fortunately, both of my patients only had PVD and no retinal tear or detachment. I asked them to follow up with our retinal specialist in 4 weeks, and return to clinic immediately if new floaters, flashes or light, or change in vision happened to them.

Summary questions:

• Can PVD cause retinal tear or retinal detachment?
  • Yes it may in a small subset of people. So always go to your eye doctor immediately if you notice new floaters or flashes of light.
• How long will I see those annoying floaters?
  • Depends on individual, some may see them for up to 6 months.
• Is there anything I can do if the floaters really bother me?
  • Please wait at least 6 months for your brain to ignore them. If they persist beyond that and bother you immensely, talk with a retinal specialist for laser or vitrectomy treatment. But be aware of risks of these treatments.

References

1. Byer NE. Natural history of posterior vitreous detachment with early management as the premier line of defense against retinal detachment. Ophthalmology. Sep 1994;101(9):1503-1513; discussion 1513-1504.
2. Uhr JH, Obeid A, Wibbelsman TD, et al. Delayed Retinal Breaks and Detachments after Acute Posterior Vitreous Detachment. Ophthalmology. Oct 23 2019.