Keeping up to date with age-related macular degeneration

WHAT DOES AGE-RELATED MACULAR DEGENERATION AFFECT?

Although Age-related Macular Degeneration (AMD) does not lead to complete blindness, the loss of central vision in AMD can interfere with simple everyday activities, such as the ability to see the faces of people in front of you, driving, reading, and writing.

OK … SO WHO IS AT RISK?        

While there are several significant factors, age is perhaps the biggest risk factor. AMD is most likely to occur after age 60, but it can occur earlier. Other risk factors include:

• SMOKING – Research shows that smoking doubles the risk of AMD.
• RACE – AMD is more common among Caucasians.
• FAMILY HISTORY AND GENETICS – People with a family history of AMD are at higher risk. At last count, researchers had identified nearly 20 genes that can affect the risk of developing AMD.
• Exposure to ultraviolet light – damage from the sun is thought to be accumulated throughout our lifetime.

So, while smoking is definitely a behaviour you can change, does lifestyle make a difference with AMD?

Researchers have found links between AMD and some lifestyle choices. You might be able to reduce your risk of AMD or slow its progression by making these healthy choices:

• Exercise regularly
• Maintain normal blood pressure and cholesterol levels
• Eat a healthy diet rich in green, leafy vegetables, fresh fruit, eat fish 2-3 times per week, eat a handful of nuts per week and try to choose low glycemic carbohydrates.
• Protect your eyes from the UV in sunlight by wearing sunglasses, especially when young. 

WHAT ARE THE SIGNS OF AMD? 

The early and intermediate stages of AMD usually start without symptoms. However, a comprehensive eye exam can detect early AMD signs. The eye exam may include the following:

• VISUAL ACUITY TEST. The eye chart measures how well you see at distances and near charts measure your near acuity.
• Internal EYE EXAM. Using a special magnifying lens, your retina and optic nerve are analysed for signs of AMD and other eye problems. Sometimes drops are needed to widen or dilate the pupils for a good view of the macula.
• AMSLER GRID. Changes in your central vision may cause the lines in the grid to disappear or appear wavy, a sign of AMD.
• Retinal photographs. Photographs can provide a useful way of assessing the macula and watching for changes over time.

An Ophthalmologist may perform other tests to assess and diagnose AMD such as:

• FLUORESCEIN ANGIOGRAM. In this test, fluorescent dye is injected into your arm. Pictures are taken as the dye passes through the blood vessels in your eye. This makes it possible to see leaking blood vessels, which occur in a severe, rapidly progressive type of AMD.
• OPTICAL COHERENCE TOMOGRAPHY (OCT). OCT is similar to an ultrasound except that it uses light waves instead of sound waves. OCT can achieve very high-resolution images of any tissues that can be penetrated by light—such as the eyes.

CAN YOU TREAT AMD?  

EARLY AMD

Although no treatment currently exists for early AMD, we recommend that you get a comprehensive dilated eye exam at least once a year. The exam will help determine if your condition is advancing. 

INTERMEDIATE AND LATE AMD

Researchers at the National Eye Institute in the USA have conducted two major clinical trials AREDS 1 and AREDS 2 (AREDS stands for Age Related Eye Disease Studies).  They tested whether taking nutritional supplements could protect against AMD. AREDS 1 found that daily intake of certain high-dose vitamins and minerals was effective in slowing progression of the disease. It showed that taking the AREDS formula everyday significantly reduced the relative risk of progression of AMD and delayed vision loss.

• Those with intermediate stage AMD reduced their risk by approximately 25%.
• Those with late stage AMD and loss of vision in one eye reduced their risk of developing severe changes in the other eye by approximately 20%.

AREDS 2 confirmed the findings of the AREDS1 study and found that adding Lutein and Zeaxanthin, while removing beta-carotene and reducing the high levels of zinc provided an additional 18% reduction in relative risk of developing advanced AMD .

The AREDS 2 formula contains  vitamin C, vitamin E,, zinc, and copper, lutein and Zeaxanthin.

At Greenlane Penrose Optometrist we have an excellent supplement in Macutec Once Daily, this supplement supplies exactly the formulation used in the AREDS 2 study.  READ more about Macutec here:

Please take note that taking a multivitamin is not a cure. It does not help people with early AMD, and will not restore vision already lost from AMD. But, it may delay the onset of late AMD. And it may also help slow vision loss in people who already have late AMD.

ADVANCED NEOVASCULAR AMD

Neovascular AMD typically results in severe vision loss. However, eyecare professionals can try different therapies to stop further vision loss. You should remember that the therapies described below are not a cure. The condition may progress even with treatment.

• One option to slow the progression of neovascular AMD is to inject drugs into the eye. They vary in cost and in how often they need to be injected, so you may want to discuss these issues with your eye care professional.
• PHOTODYNAMIC THERAPY. This technique involves laser treatment of select areas of the retina. First, a drug called verteporfin will be injected into a vein in your arm. Your eye care professional then shines a laser beam into your eye to activate the drug in the new abnormal blood vessels, while sparing normal ones. Once activated, the drug closes off the new blood vessels, slows their growth, and slows the rate of vision loss.
• LASER SURGERY. This laser is not the same one used in photodynamic therapy which may be referred to as a “cold” laser. This treatment is more likely to be used when blood vessel growth is limited to a compact area in your eye. Even so, laser treatment also may destroy some surrounding healthy tissue. This often results in a small blind spot where the laser has scarred the retina.

Are you looking to book a comprehensive eye? Hopefully you do not have any AMD signs, but if you do, we can detect them now. Please email Jenny at jenny@gp-optom.co.nz