Flashes and Floaters: Early Signs of Retinal Detachment

"If you see new flashes or floaters, call me right away."

This is my catchphrase that I, and probably every retina specialist, say many times a day. In fact, I give this warning at the end of almost every patient visit. It bears repeating because symptoms of flashes or floaters could be a red flag of a serious condition, retinal detachment. A retinal detachment has the potential to cause permanent blindness. More importantly, when diagnosed and treated early, the surgical results are very good and there is a high chance of preserving most, or even all, of your vision.  This is why we want every patient to act promptly if they ever experience these visual symptoms, and get in touch with a retina specialist or ophthalmologist right away. Let's delve into what exactly flashes and floaters look like, where they come from, and what to do about them.

Dark floaters obstructing the vision

What Are Flashes and Floaters?

Floaters are tiny shapes that drift across your field of vision. They may look like specks, threads, squiggly lines, or even cobwebs. They are usually a dark color, such as gray or black, but can sometimes appear lighter or even clear with only an amoeba-like outline. They are most noticeable when you're looking at a bright background such as a blue sky or a white wall. For this reason, many people will see floaters while at the beach. The floaters are actually small clumps of cells or liquefied vitreous, which is the clear gel-like substance that fills the inside of your eye. Sometimes, the floaters can be red blood cells from a torn blood vessel in the retina. This is called a vitreous hemorrhage.

Flashes, on the other hand, look like brief flickers or streaks of light, similar to seeing lightning out of the corner of your eye. They are most noticeable in the dark, usually at the side of your vision, and occur when moving your eyes around. The flashes are due to the vitreous tugging on the retina, the light-sensitive tissue lining the back of your eye. The vitreous gel is normally attached to the retina, so every movement of the gel agitates the retina and causes it to send a light flash signal to your brain. If there is enough tugging, or traction, from the vitreous gel, then the retina will rip. This is called a retinal tear. If the rip also happens to go through a blood vessel, then a vitreous hemorrhage develops.

What Causes Flashes and Floaters?

So why would the vitreous tug? Aging is the most common cause of vitreous traction. After the age of 50, the vitreous gel naturally begins to liquefy and pull away from the retina. This is called a posterior vitreous detachment (PVD). Most PVDs are harmless and don’t require treatment. However, if the pulling leads to a retinal tear or retinal detachment, then urgent treatment is needed or else the vision can be permanently lost.

Besides vitreous tugging, there are other causes of flashes and floaters that are not related to age. These include:

• Inflammation (Uveitis): This can cause debris in the vitreous, leading to floaters.

• Injury or trauma: A direct blow to the eye or head can cause bleeding inside the eye, as well as severing the normal attachment of the vitreous to the retina, causing a premature PVD and leading to flashes and floaters.

• Migraines: Migraine auras can sometimes mimic visual flashes, though they usually present as colorful patterns and are associated with a headache, though not always.

Flashes of light appearing as "rain" of light

Diagnosing the Cause

If you report new flashes or floaters, your eye doctor will perform a dilated eye exam to assess the retina thoroughly. This involves using eye drops to widen (dilate) your pupils so the retina can be visualized in detail. Photographs of the retina may also be taken, although they do not replace the need for a direct exam. A dilated eye exam with scleral depression is considered the standard of care by the American Academy of Ophthalmology to evaluate for retinal tears and detachments. It is the only way to definitively assess 100% of the retina to ensure no small problem areas are missed. While wide-field photographs of the retina can be helpful and are often offered by various eye care providers, they are not a substitute for a skilled exam.

Additional testing may include:

• Optical Coherence Tomography (OCT): Provides high-resolution images of the retina

• Ultrasound: Helpful if the view of the retina is blocked, such as in cases of vitreous hemorrhage

  
  

If a retinal tear or detachment is found, treatment will be recommended right away.

When Should You Be Concerned?

Some floaters and flashes are just part of the normal aging process, but others are a red flag. So how do you know the difference?

Call your retina specialist right away if you experience:

• A sudden increase in floaters, especially if they look like a "shower" or "cloud" of dots

• Flashes of light that are persistent or increasing

• A shadow or curtain coming across your vision

• A decrease in your side (peripheral) vision

  
  

These symptoms could indicate a retinal tear or detachment, which requires urgent care to preserve your sight.

However, it is also possible to have a slowly developing (subacute) retinal tear or detachment without the above symptoms. Therefore, it is extremely important to maintain regular follow up with your eye doctor as directed. Retinal tears and retinal detachments are not reversible, but they can be treated.

Black curtain or shadow seen in the peripheral or side vision, indicating retinal detachment

How Are Retinal Tears and Detachments Treated?

If a retinal tear is detected early, it can often be treated in the office with a laser or a freezing treatment (cryopexy) to seal the tear and prevent detachment. If a retinal detachment has already occurred, surgery is usually required. The type of surgery depends on the specifics of the case, but common procedures include:

• Vitrectomy: Removal of the vitreous gel and repair of the retina

• Scleral buckle: A flexible band placed around the eye to gently push the wall of the eye against the retina

• Pneumatic retinopexy: A gas bubble is injected into the eye to help the retina reattach

  
  

The sooner a retinal problem is diagnosed and treated, the better the chances of preserving vision. This is why I advise all my patients to contact me right away if they develop symptoms. Notwithstanding the vision implications, it could also mean the difference between a 10-minute non-invasive laser procedure in the office, or a full-blown surgery with anesthesia required to be performed at the hospital.

Depending on your local resources, I also recommend seeing a fellowship-trained retina specialist to evaluate your condition, if possible. Retina specialists, and in particular, retinal surgeons, have undergone rigorous training and possess the necessary technical skill to perform any of the above treatments that you might need. Click here to learn about the educational background of a retina specialist.

Horseshoe retinal tear causing a retinal detachment

This image was originally published in the Retina Image Bank. Jason S. Calhoun. Horseshoe Retinal Tear. Retina Image Bank. 2013; Image Number 7030. © the American Society of Retina Specialists

Living With Floaters

If your floaters are not caused by a serious issue, they may simply be something you live with. Most people find that floaters become less noticeable over time as the brain adapts and learns to ignore them. Occasionally, if floaters are extremely bothersome and impact your vision significantly, a vitrectomy can be performed to remove them. You should discuss the risks and benefits with your retina specialist to see if you are a candidate for this procedure.

Common Questions From Patients

• Is there anything I can do to improve or resolve floaters and flashes?

  • Unfortunately, there is no special activity or diet or any external modification that is possible to reduce the symptoms. The good news is that they usually diminish on their own with time, as the vitreous gel stabilizes and as your brain adjusts to notice them less. This process can take several months. The only way to actually remove floaters is to physically extract them with vitrectomy surgery by cutting out the vitreous gel. Some eye doctors also offer laser vitreolysis, which uses laser energy to vaporize floater cells. Although considered less invasive than vitrectomy surgery, this procedure is less definitive as the vitreous substance remains inside the eye and is not removed. Both procedures bear some risk, and should be carefully considered and discussed with your retina specialist, who can review your individual situation.

    
    

• Was it something that I did to cause the floaters and flashes?

  • Usually not. Again, the most common cause of floaters and flashes is natural aging of the vitreous gel. Direct trauma to the eye or head can predispose you to floaters and flashes. If you engage in contact sports or are otherwise at higher risk of getting a retinal tear or detachment, you may want to consider wearing eye protection.

    
    

• Will I get floaters and flashes in my other eye?

  • Yes, you can expect to develop symptoms of floaters and/or flashes in the other eye as the second eye undergoes the aging process. However, the timing is not identical and you may experience the symptoms a few months to years later. As far as PVD goes, the two eyes are independent of each other, so it's possible that your symptoms the second time around could be more or less severe compared to previous. If you've had a retinal tear or detachment in one eye, it doesn't mean that you are condemned to having the same bad luck in the other eye. However, because it's not possible to rule out a retinal tear or detachment without an eye exam, we always recommend a visit to your eye doctor whenever you have new symptoms.

Final Thoughts

I know it can sound like a broken record: "Call me if you see new flashes or floaters." However, if sharing this helps even one person avoid permanent vision loss, it's worth saying as often as needed. The retina doesn't regenerate, so we can't take chances.

At Beacon Retina, we take every report of flashes or floaters seriously. Whether it's something benign or something more urgent, you're never bothering us by checking in. We want to protect your sight, give you peace of mind, and guide you every step of the way.

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Dr. Sophia Wong is a retina specialist, surgeon and board-certified ophthalmologist. She established Beacon Retina, the first concierge ophthalmology practice in the Washington, D.C. metro region, to prioritize thoughtful, patient-centered care for preserving long-term vision.