Macular edema is a swelling of the macula, the part of the eye responsible for central vision. When fluid builds up in the macula, it becomes swollen and thicker. This distorts vision. There are several causes, including diabetic retinopathy, post-eye surgery complications, macular degeneration, injury, systemic inflammatory diseases that can affect the eye, and/or vein blockages. If an eye disease causes damage to blood vessels in the retina, it can cause macular edema. Left untreated, this problem can cause serious vision loss and even blindness.
An eye doctor will direct your care should macular edema occur. Standard treatment focuses on controlling and reducing the macula edema, typically through steroid eyedrops or possibly eye injections. Though the eye doctor often will try to find the underlying causative factor through various blood tests for example, often the problem may appear idiopathic (no obvious cause). Research has shown that certain nutrients, including antioxidants, can help reduce and manage inflammation throughout the body and help protect the retina from damage.
If you are having problems with vision, consult an eye doctor. An eye doctor has many ways of testing central vision. One screening test you can try at home is the Amsler Grid.
How Macular Edema Is Diagnosed
Symptoms of macular edema include:
- wavy central vision
- colors look washed out or different than usual
- vision loss in either eye
Anyone with these symptoms should consult an ophthalmologist. The eye doctor may utilize several tests, including:
- visual acuity test (reading the eye chart)
- dilated eye exam (drop open the iris so the doctor can painlessly look inside)
- Fluorescein angiogram (a dye is injected in the arm to get a better view of where the weak blood vessels in the eye(s) may be)
- Optical coherence tomography (special light and camera observes the layer cells of the retina)
- The Amsler Grid (look at a special grid and note any distortions)
How to Test Central Vision at Home: Diabetics and seniors at risk of macular degeneration can screen their own central vision weekly or monthly using the Amsler Grid. This can be done at home in minutes. Instructions and a printable grid are available on the Natural Eye Care website.
Types of macular edema are:
- Cystoid macular edema (CME): the swelling is enclosed in a microscopic capsule
- Diabetic macular edema (DME): capillaries in the macula leak
Swelling may be focal (in the center of the macular, called the fovea) or diffuse (affecting other capillaries in the retina).
Causes of Macular Edema
A large at-risk group is diabetics. Anyone with diabetes needs to be on the lookout for symptoms of diabetic macular edema (DME). For working age Americans, DME is the most common reason for blindness, and it is irreversible. In diabetic retinopathy, the small blood vessels in the retina are damaged by blood sugar abnormalities. Fluid leaks into the retina, causing swelling that may include the macula.
If you have recently had eye surgery, your eye surgeon will explain which symptoms to watch for. Consult with the doctor as soon as possible if you notice any problems. While complications from cataract surgery are uncommon, macular edema can happen. Anti-inflammatory eye drops prescribed by the eye surgeon typically clear up symptoms quickly.1
Age-Related Macular Degeneration (ARMD) is the gradual breakdown of the macular cells. The more advanced version, “wet” ARMD, causes the growth of abnormal blood vessels in the eye which are weak and tend to leak. This can result in macular edema.
Patients with genetic diseases that affect the retina such as retinitis pigmentosa can develop macular swelling.
Retinal vein occlusion can cause macular swelling. Blood leaks into the retina, causing damage. Risk factors include atherosclerosis (hardening of the arteries), high blood pressure, diabetes, glaucoma, and eye inflammation.
Inflammatory diseases of the eye such as uveitis can spread to affect other parts of the eye including the macula. Macular edema can be caused by systemic inflammatory diseases such as sarcoidosis, cytomegalovirus infection, toxoplasmosis, retinal necrosis, sarcoidosis, Eales’ disease, Rheumatoid Arthritis, Behçet’s syndrome, and Vogt-Koyanagi-Harada syndrome.
The long-term outlook for a patient with macular edema depends on how treatable the underlying cause is and patient cooperation with managing the treatment symptoms. Without an official diagnosis and treatment, irreversible blindness may result.
The underlying cause of macular swelling will direct the treatment plan. If the cause is diabetes or high blood pressure, all measures should be taken to get these diseases under control quickly. Any damage to the retina should be treated if necessary.
While focal laser photocoagulation was common in the past, injecting drugs directly into the eye is now a popular and proven treatment. However, eye injections do not address the underlying cause.
Numbing drops make anti-VEGF injections typically painless. A short, thin needle is used to inject one of several medications into the fluid in the center of the eye (vitreous gel). The drug might be Lucentis, Avastin or Eylea. They block vascular endothelial growth factor (VEGF). While VEGF is fine for normal eyes, abnormal blood vessel growth in the eye is harmful. The drug slows the progression of macular edema by inhibiting the growth of leaky blood vessels in the eye.
If the swelling is caused by an inflammatory disease, Corticosteroid (steroid) treatments may be utilized. They may come in the form of pills, drops or injections. If the problem is chronic, a sustained-release corticosteroid implant may be inserted.
Eye drops containing NSAIDs (nonsteroidal anti-inflammatory drugs) can be used in conjunction with cataract surgery to prevent macular edema. They may also be used if steroids are not suitable.
A surgery called a vitrectomy removes some of the vitreous gel. This may relieve symptoms or correct problems in serious cases of macular degeneration.
Inflammatory diseases that can spread to the eye each have their own specific treatment protocols.
In cases of injury causing macular edema, an ophthalmologist or emergency room doctor should be consulted immediately.
Other Approaches to Macular Edema Support and Prevention
The health of the eye can be greatly influenced by lifestyle and diet. Macular edema is a symptom of an underlying eye condition. You have control over some of the factors that can lead to eye damage:
- Don’t smoke. Smoking damages the macula2 3
- Exercise for at least 20 minutes every day.
- Wear the right type of sunglasses whenever you are in natural light.
- Do these simple eye exercises regularly.
- Eat a nutritious diet. The eye depends on essential nutrients for maintaining healthy vision. One good diet to consider is the Mediterranean Diet.
Cooperate with the treatment your doctor is providing for the problem underlying macular edema. For example, if you have diabetes and fail to control your blood sugar levels, you can get diabetic retinopathy. One study found that less than 50% of Type II diabetics successfully met their glycemic goals.4 Blindness is an abstract, in-the-future, but very real possibility.
If you have high blood pressure, keep it under control. Otherwise, you could develop a retinal vein occlusion that damages the retina, causing vision loss and macular edema.
Try to avoid getting macular degeneration in older age by ingesting enough carotenoids and other antioxidant through a healthy diet and targeted supplementation. Even if you develop the disease, it is not too late to eat more dark, leafy greens, and brightly colored produce. These substances protect against oxidative damage. Research has shown they can specifically protect against macular degeneration. 5 6 Macular degeneration tends to coincide with to Azlheimer’s disease, and some studies looked at both diseases at once.7
Macular swelling from cataract surgery is usually mild and temporary. Comply with the eye surgeon’s instructions. If you need to delay lens replacement surgery, read this article about an alternative way to address cataracts.
If an inflammatory disease is underlying macular edema, take a look at our information on natural anti-inflammatory approaches. Chronic inflammation can damage all parts of the body. At Natural Eye Care, we have developed a Vision Diet designed to minimize inflammation and provide essential nutrients to the eyes. Sufficient antioxidant intake, curcumin8, Omega-3 fatty acids and other supplements have been found to cut inflammation biomarkers. Learn more on our Inflammation and Health page.
Research on Macular Edema
The macula is a tiny, yellowish spot on the retina. It gets its color from the pigments of lutein and zeaxanthin. These strong antioxidants are available from nutritional and supplemental sources, such as dark leafy greens (especially cooked spinach), orange peppers, egg yolks, sweet corn, broccoli, summer squash (zucchini), and green peas. Some research has specifically looked at macular edema. A larger body of peer-reviewed research shows that the health of the macula can be heavily influenced by diet and lifestyle.
Supplemental lutein and zeaxanthin may be useful for symptoms of diabetic retinopathy, including macular edema. One study found that concentrations of lutein and zeaxanthin in the blood were much lower for nonproliferative diabetic retinopathy patients versus controls. Also, the patients who received supplements gained better visual acuity, improved contrast sensitivity, reduced foveal thickness and reduced macular edema over three months.9
A small study found that supplemental oxygen reduced symptoms of diabetic macular edema10. Excess foveal thickness and macular volume were reduced. The oxygen, breathed in through a nasal cannula, seemed to help excess blood vessels shrink.
Higher levels of iodine in the body were associated with a reduction in macular edema in retinitis pigmentosa patients11 and vice versa. This suggests that sufficient iodine intake, and possibly supplementation, may be beneficial.
Preventing the build-up of fluid in the macula helps preserve vision and maintain the quality of life. Preventing and treating the conditions underlying macular swelling is key. Eye health is heavily influenced by overall health, lifestyle and diet.
- J Cataract Refract Surg. 2016 Sep;42(9):1368-1379. doi: 10.1016/j.jcrs.2016.06.006. Cataract surgery and nonsteroidal antiinflammatory drugs. Hoffman RS, Braga-Mele R, Donaldson K, Emerick G, Henderson B, Kahook M, Mamalis N, Miller KM, Realini T, Shorstein NH, Stiverson RK, Wirostko B; ASCRS Cataract Clinical Committee and the American Glaucoma Society. ↩
- Researchers: T.D. Keenan, M. Toso, C. Pappas, L. Nichols, P.N. Bishop, G.S. Hageman. Published: Assessment of Proteins Associated With Complement Activation and Inflammation in Maculae of Human Donors Homozygous Risk at Chromosome 1 CFH-to-F13B, Investigative Ophthalmology and Visual Science, July, 2015. ↩
- Researchers: D. Stanislovaitiene, et al. Published: SCARB1 rs5888 is associated with the risk of age-related macular degeneration susceptibility and an impaired macular area, Ophthalmic Genetics, July, 2016 ↩
- Diabetes Ther. 2013 Dec; 4(2): 175–194. Published online 2013 Aug 30. doi: 10.1007/s13300-013-0034-y. PMCID: PMC3889324. “Adherence to Therapies in Patients with Type 2 Diabetes” Luis-Emilio García-Pérez et. al. ↩
- “Neovascular age‐related macular degeneration and its relationship to antioxidant intake” in Acta Ophthalmologica Scandinavica 80(4):368 – 371 · August 2002 ↩
- Seddon JM, Ajani UA, Sperduto RD, et al. Dietary carotenoids, vitamins A, C, and E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group. JAMA. 1994;272(18):1413-1420. ↩
- “Macular pigment, visual function, and macular disease among subjects with Alzheimer’s disease: an exploratory study.” Nolan JM et. al. J Alzheimers Dis. 2014;42(4):1191-202. doi: 10.3233/JAD-140507. ↩
- BK McFarlin, et al, Reduced Inflammatory and Muscle Damage Biomarkers Following Oral Supplementation with Bioavailable Circumin, BBA Clinical, June, 2016 ↩
- Int J Ophthalmol. 2011;4(3):303-6. doi: 10.3980/j.issn.2222-3959.2011.03.19. Epub 2011 Jun 18. “Application of Lutein and Zeaxanthin in nonproliferative diabetic retinopathy.” Hu BJ et. al. ↩
- Invest Ophthalmol Vis Sci. 2004 Feb;45(2):617-24. “Supplemental oxygen improves diabetic macular edema: a pilot study.” Nguyen QD et. al. ↩
- “The Relationship of Central Foveal Thickness to Urinary Iodine Concentration in Retinitis Pigmentosa With or Without Cystoid Macular Edema” by Michael A. Sandberg et. al. JAMA Ophthalmol. 2014;132(10):1209-1214. doi:10.1001/jamaophthalmol.2014.1726 ↩