Flashes, Floaters, and Retinal Tear/Detachment
What are flashes and floaters?
Flashes and floaters are a common sight for many people and usually occur when the vitreous (the clear gel-like material that fills the eyeball) pulls away from the retina (the light sensitive tissue lining the back of the eye) as part of the normal aging process. You may also see flashes and floaters as a result of an injury, diabetic changes, or in patients who are extremely nearsighted. The symptoms of flashes and floaters are exactly what the terms suggest. Flashes are sparks or strands of light that flicker across your visual field. Floaters are how we refer to the specks, threads, or cobweb-like images that occasionally drift across your line of vision. Both are usually harmless, but they can be warning signs for a retinal tear or detachment.
What is a Retinal tear or Detachment and what are the Symptoms?
Retinal tears commonly occur when the vitreous moves away from the retina without detaching, pulling hard enough to tear the retina in one or more places, but can also be caused by inflammation or extreme nearsightedness. Retinal tears are generally small and happen in the peripheral retina, so a decrease in vision from a tear is highly unusual. Symptoms include:
- No pain
- Flashes and floaters
- A sudden or gradual increase in the size and number of floaters
A retinal detachment happens when the retina pulls away from the layer of blood vessels that provides it with oxygen and nourishment. Retinal detachments commonly occur when fluid passes through a retinal tear, lifting the retina off the back of the eye (like peeling apart the layers of a tissue), but can also be caused by injury, advanced diabetes, inflammatory eye disorders, and extreme nearsightedness. Symptoms include:
- No pain
- Flashes and floaters
- A sudden or gradual increase in the size and number of floaters
- A shadow or curtain over a portion of your visual field (develops as the detachment progresses)
How do we treat flashes and floaters?
If you are having flashes and/or floaters, it's best to be seen for a dilated exam as soon as possible due to the possibility of a retinal tear. If nothing more serious is found during an examination, we will observe and the floaters and flashing lights will gradually grow fainter over several weeks or months. The floaters may never completely disappear since the vitreous is always present in the eye. Our brains often learn to “ignore” the floaters that remain. We may see them occasionally while reading, looking at a blank wall or the clear blue sky. In some patients, the floaters cause a significant, persistent visual disturbance. These patients may be candidates for an elective surgery (called a vitrectomy) to remove the floaters.
How do we Treat a Retinal Tear or Detachment?
Treatment of a retinal tear is aimed at creating an adhesion between the retina and the back wall of the eye. If the tear is within range, laser can be used to "spot weld" the retina down - using enough shots to create 3-4 rows of laser spots around the tear to prevent further tearing or detachment. If the tear is outside the range of the laser, cryotherapy (using liquid nitrogen) can be used to freeze around the tear from the outside of the eye.
Treatment of a retinal detachment is aimed at repositioning and anchoring the separated retina against the back wall of the eye. Surgery is the most common choice for repairing a retinal detachment. Different surgical methods may be used depending on the location and extent of the detachment and may include one or more of the following:
- Scleral Buckle - A flexible piece of silicone rubber is then permanently sewn to the sclera (white of the eye) to support the area of tears and detachment. This indents or "buckles" the eye helping prevent fluid from passing through the tear.
- Vitrectomy - As much of the vitreous as possible is removed from the eye, fluid that has accumulated under the retina is removed to flatten the retina, and a laser is applied to the peripheral retinal and around all tears to secure the retina in place. A vitrectomy can be used alone or in combination with a scleral buckle in detachments with unusual or difficult features, such as very large tears, scar tissue on the retina, excessive blood in the vitreous, or detachments that failed by other methods.
- Gas Bubbles - A concentration of long-acting gas is used to push against the retina while laser and/or cryotherapy scars form. This form of treatment requires most patients to adhere to strict positioning to keep the bubble pushing against the treated areas. Other restrictions include no traveling by air or to high altitudes and no dental work or general anesthetic with nitrous oxide as these may all cause the gas bubble to expand.
- Silicone Oil - If it is impossible for the patient to maintain positioning, or if the detachment is very complex, a clear silicone oil can be used instead of gas. Face down positioning is overnight, and the patient can be in any position other than flat on his/her back while the silicone oil is present. However, this approach necessitates an additional surgical procedure for oil removal approximately 3 months later. Because of the different refractive properties of silicone oil, vision is also very blurry while the oil is present.
A retinal detachment is a medical emergency. Anyone experiencing the symptoms of a retinal detachment should make an appointment to be seen immediately with your SMO ophthalmologist - we will make sure you get seen the same day and have a doctor on call if your emergency is after-hours. If not promptly treated, a retinal detachment can cause permanent vision loss.