Age-related
Macular Degeneration
Age-related Macular Degeneration (AMD) is a common eye condition and a leading cause of vision loss among people age 50 and older. It causes damage to the macula, a small spot near the center of the retina. The macula lets us see objects that are straight ahead, and is crucial for the sharp, central vision required in activities such as reading and driving.
Types of AMD
Dry AMD
Dry AMD is a condition where the macula thins out over time, typically over months or years. Waste products also accumulate under the macula, causing deposits known as drusen. Together, they result in the gradual blurring of central vision in that eye. The majority of patients with AMD will suffer from dry AMD.
Wet AMD
Wet AMD occurs when abnormal blood vessels grow under the macula and retina. These vessels may suddenly leak fluid or blood, and results in a rapid and severe drop in the central vision of that eye. If left untreated, a scar will form under and within the macula, which is irreversible.
Wet AMD is less common than dry AMD, but the visual loss in wet AMD is usually more severe.
Risk Factors for AMD
While some factors are beyond our control, others can be managed through lifestyle choices.
Advancing Age
Age is the most important risk factor. The likelihood of developing AMD increases significantly after the age of 50.
Family History
Individuals with a family history of AMD are at a higher risk, and certain genes have been found to increase your risk of developing AMD.
Smoking
Smoking doubles the risk of AMD, compared to non-smokers. It causes oxidative stress to the cells of the retina, and reduces blood flow to the eyes.
Other Factors
Obesity, high blood pressure, and heart disease have been associated with AMD. A diet that is low in antioxidants may also contribute to your risk.
Symptoms of AMD
Visual Distortion (Metamorphopsia)
Straight lines, such as door frames or lines of text, may appear wavy, bent, or distorted.
Blurred Central Vision
The loss of central vision can make it difficult to recognize faces, read small print, or see fine details.
Dark or "Blind" Spots in the Vision
The appearance of a blind spot, or a dark area in your field of vision, can cause you to miss seeing people or objects before you.
Diagnosing AMD
Comprehensive Eye Examination
The first step is a detailed assessment of your visual acuity and a dilated eye exam to inspect the retina and macula for signs of AMD.
Optical Coherence Tomography (OCT)
A form of non-invasive 3D imaging that provides high-resolution cross-sections of the macula and retina. This is essential for detecting fluid or bleeding in 'wet' AMD.
Digital Retinal Photography
High-quality digital images of the back of the eye allow our specialists to document and monitor any changes in the macula over time.
Fundus Fluorescein Angiography (FFA)
In certain patients, an FFA may be performed to determine the point of bleeding in the macula. A yellow dye ("fluorescein") is injected into the vein on your hand, and allowed to circulate into your body. A special camera is used to take high-speed photographs of the dye as it flows through the blood vessels of the retina, allowing your specialist to detect any leaking vessels under the macula.
Treatment & Ongoing Care
While there is currently no cure for AMD, management aims to preserve vision and slow progression through medical or lifestyle interventions.
Intravitreal Injections : Injections of anti-VEGF medications into the eye can reduce leakage and bleeding from abnormal blood vessel growth in wet AMD. The use of these anti-VEGF (vascular endothelial growth factor) medications has revolutionised the management of wet AMD, allowing patients to regain vision with regular injections.
Supplements & Lifestyle Changes : Vitamins like the "AREDS-2" supplements have been shown to reduce the risk of developing wet AMD in certain patients. Smoking cessation, control of your weight and blood pressure, and diets rich in antioxidants may also slow the progression of dry AMD.
Ongoing Monitoring : Regular home monitoring with an Amsler Grid is important in detecting any worsening of your condition, in between regular doctor's visits.
Preventing AMD
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Stop Smoking : This is the best thing that you can do to lower your risk of AMD, as well as improve your overall health.
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Lifestyle Changes : Maintaining good health through regular exercise and a nutritious diet, rich in antioxidants, can lower your risk of developing AMD. Sunglasses with UV-protection may also be helpful.
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Regular eye screening : Eye exams can detect the early change of AMD. Patients who are 50 years and older, and especially those with risk factors for AMD, should have a regular yearly eye examination.