What is macular edema?
Macular edema is swelling of the macula caused by leakage or accumulation of fluid in retinal tissue. When disease or inflammation damages the normal barrier of retinal blood vessels, fluid can leak into the retinal layers and disturb the delicate structure of the macula.
It can occur in one eye or both. It is different from macular degeneration, although both conditions involve the macula. Macular edema specifically describes swelling caused by fluid accumulation and can develop as a complication of several different eye diseases.
Common causes
- Diabetic retinopathy and diabetic macular edema
- Retinal vein occlusion, which can cause leakage and swelling
- Uveitis and other inflammation inside the eye
- Swelling after eye surgery, including cataract surgery
- Wet age-related macular disease and other retinal conditions
Symptoms of macular edema
Symptoms vary depending on the severity and cause. Some people notice only mild blurring at first, while others find reading, recognising faces or detailed work increasingly difficult.
- Blurred central vision
- Wavy or distorted vision, with straight lines appearing bent
- Difficulty reading small print
- Colours appearing faded or less vivid
- A central blurry or dim area
- Vision that gradually becomes worse
How is it diagnosed?
Diagnosis begins with a detailed eye history and retinal examination. Dilated examination allows the ophthalmologist to look for retinal disease, bleeding, swelling and other abnormalities.
Optical coherence tomography (OCT) produces detailed cross-sectional images of the retina. It can show retinal thickening and pockets of fluid, and helps the retina specialist compare the macula over time. In selected cases, fluorescein angiography may help identify the pattern or source of leakage.
Treatment options
- Anti-VEGF injections to reduce leakage and retinal fluid
- Steroid treatment for selected inflammatory or diabetic cases
- Anti-inflammatory eye drops after certain surgeries
- Laser treatment in selected diabetic or vein-occlusion cases
- Vitrectomy or other surgery when traction or vitreous abnormalities are involved
When should you see a retina specialist?
Do not ignore new or worsening central vision changes. Seek an examination if straight lines suddenly look wavy, reading becomes unexpectedly difficult, colours look different or central vision becomes blurred. Sudden or significant vision loss needs prompt medical assessment.
