Medical Retina: Diabetic Retinopathy, AMD and Eye Injections

What is medical retina?

The retina is the thin layer of nerve tissue that lines the back wall of the eye and turns incoming light into signals carried by the optic nerve. Medical retina covers the diagnosis, monitoring and treatment of diseases of this layer without surgery, using imaging, medication, eye injections and laser. The macula, at the center of the retina, is responsible for reading, recognizing faces and seeing fine detail, so diseases in this area have a direct effect on daily life.

Many retinal diseases cause no pain or obvious symptoms at first. That is why regular dilated retinal exams play a decisive role in protecting vision in people at risk.

Which conditions does medical retina cover?

Diabetic retinopathy and diabetic macular edema

Long-term high blood sugar damages the small blood vessels of the retina. Fluid leaking from these vessels can cause swelling (edema) in the macula, and in advanced stages abnormal new blood vessels and bleeding can develop. Everyone diagnosed with diabetes is advised to have a dilated retinal exam at least once a year.

Age-related macular degeneration (AMD)

AMD usually appears after the age of 50 and affects central vision. In the dry form, changes progress slowly. In the wet form, abnormal blood vessels grow beneath the macula and cause leakage and bleeding, which can affect vision within a short time. Wet AMD is treated with eye injections.

Retinal vascular occlusions

A blockage in a retinal vein or retinal artery can cause sudden vision loss. High blood pressure, diabetes and high cholesterol are risk factors. Macular edema caused by a retinal vein occlusion may be treated with eye injections or laser.

Other conditions

• Central serous chorioretinopathy (fluid build-up under the macula)
• Macular edema that can develop after cataract surgery
• Uveitis and inflammatory retinal diseases
• Retinal changes caused by high myopia (severe nearsightedness)

Which symptoms mean you should have an eye exam?

• Straight lines (door frames, tile joints) looking bent or wavy
• A shadow, smudge or blank patch in the center of your vision
• Letters disappearing as you read, or colors looking faded
• Sudden or rapidly worsening blurred vision in one eye
• A sudden increase in floaters, or flashes of light

If you notice any of these symptoms, and especially if you have diabetes or are over 50, you are advised to have an eye exam without delay.

Tests used for diagnosis

1. Dilated retinal exam: The pupil is widened with eye drops so that the retina, macula and optic nerve can be examined.
2. OCT (optical coherence tomography): A non-contact scan that uses light to create cross-sectional images of the retinal layers. Swelling and fluid are measured in microns (thousandths of a millimeter), and the scan is also used to monitor treatment.
3. Fundus fluorescein angiography (FFA) and OCT angiography: Requested when needed to show leakage, blockages and abnormal vessels in the retinal blood vessels.

Treatment options

Eye injections (intravitreal anti-VEGF therapy)

In wet AMD, diabetic macular edema and macular edema caused by a vein occlusion, medicines that suppress abnormal blood vessel growth and leakage are injected into the eye. The procedure is done under sterile conditions after numbing eye drops, using a very fine needle, and takes a few minutes. Treatment is usually planned as a series, and the intervals between injections are set according to OCT findings.

Laser treatment

Laser photocoagulation may be used in some stages of diabetic retinopathy and around retinal tears. The aim is to reduce leakage and abnormal blood vessel growth, or to reinforce the retina around a tear.

Follow-up and managing your general health

Most retinal diseases need long-term follow-up. Keeping blood sugar, blood pressure and cholesterol under control plays an important role in the success of treatment, so it is advisable to be monitored together with your internal medicine doctor and your endocrinologist.

Who should have regular retinal check-ups?

• People with diabetes (at least once a year from diagnosis)
• People over 50 and those with a family history of macular degeneration
• People with high blood pressure
• People with high myopia
• People who take certain medicines long term (for example, hydroxychloroquine)

Your retinal assessment and treatment plan are tailored to your examination findings. Next steps and follow-up intervals are decided together with you at your examination.