The Aging Eye: Cataracts And Macular Degeneration

By Dottie Evans

Dr Thomas A. Margius, PC, spoke Tuesday, April 20, at Lockwood Lodge at Ashlar of Newtown during a Lunch and Learn program at The Learning Center. His topic was “Cataracts and Macular Degeneration,” two progressive diseases of the eye that most often occur in an individual over the age of 50.

Although both diseases share several common risk factors, such as genetic history, smoking, diabetes, and long-term exposure to ultraviolet rays found in sunlight, Dr Margius chose to consider cataracts and macular degeneration separately, looking at unique physiological aspects and treatment options for each.

“In either case, treatment is a functionality and quality-of-life issue. You should feel encouraged by the knowledge that living where you do, there are a number of fine doctors where you may go for assistance,” he said.

Dr Margius is a licensed optometrist with a practice at 122 Broad Street, Milford, and he is the consulting optometrist for Ashlar of Newtown.

 

Cataracts: Symptoms

And Treatment

“A cataract is the clouding of the lens of the eye,” Dr Margius said, adding that since the lens must be clear in order to focus a visual image on the back of the retina, eventually all cataracts must be treated or sight in the diseased eye may be severely compromised or lost.

The cause of clouding may be clumps of protein that form within the lens, or by changes in the lens color from clear white to yellowish or even brownish.

“At first, the vision is duller and blurrier. Then the colors go out,” Dr Margius said.

Cataracts can come as the result of diabetes causing an excess of fluid in the eye, or after a traumatic injury –– showing up perhaps years later. They can be congenital, or they may result from exposure to radiation.

“In the examining room, we can detect a cataract after dilation and a visual acuity test, or through tonometry, which is the measurement of fluid pressure within the eye.”

Treatment may be with new eyeglasses and the use of brighter lighting, or through surgery, which is the best option when activities such as driving, reading, or watching TV are threatened.

“Cataract removal is one of the most common operations performed in the United States, and it is 90 percent effective,” Dr Margius said.

There are two types of cataract surgery currently available: phacoemulsificaiton or “phaco” surgery, or extracapsular surgery.

In phaco surgery, the more common form, a small incision is made on the side of the cornea and the cloudy material is withdrawn after it has been broken down. This is done when a probe is inserted and device emits ultrasound waves that soften and break up the lens before removal of the material.

With phaco, or small incision surgery, the outer “bag” or “pouch” that holds the lens material is left intact and a new, artificial lens is inserted.

The less common extracapsular surgery involves a longer incision and the entire lens is removed in one piece. Then a lens implant is introduced in its place.

With both methods, there is the possible benefit of providing sharper vision through altering the shape of the new lens to match more closely the prescription of corrective glasses the patient may have previously worn.

 

Age-Related Macular

 Degeneration (AMD)

In its earliest stages, age-related macular degeneration (AMD) presents one symptom that is similar to the first complaint of a person with a cataract, which is blurred vision with no pain.

But the unique problem with AMD is that the blurriness occurs at the macula, or focal spot, on the back of the retina, which is the exact center of vision.

“This is where there is the greatest concentration of light-sensitive tissue. The patient may find that the side, or peripheral, vision is OK, and the blurriness occurs only in the center.”

The two types of AMD described by Dr Margius were wet AMD and dry AMD.

“Wet AMD happens when the blood vessels under the retina become filled with fluid and actually raise or lift the macula up and away from the retina. There is usually leakage of blood or fluid that accompanies this condition,” he said.

A person suffering from wet AMD notices that there is a waviness or distortion near the center vision. For early stage AMD, there is a home test known as the Amsler grid that can help with diagnosis.

“The patient puts the grid, which is really a piece of graph paper, on his or her bathroom mirror and checks for increasing distortions at the center,” he added.

Dry AMD, the more common condition, occurs when light-sensitive cells of the macula begin to break down.

“A person may first notice small spots in the back of the eye called drusen, or a blurred place where there are a lot of drusen in the center vision. Again, more light is needed to see. Eventually, with long term AMD, the drusen increase in size and number causing a black hole at the center.”

“Lasers can be used to treat wet AMD by destroying the fragile blood vessels. This is followed immediately by photodynamic therapy in which the drug verteporfin is injected into the arm. The drug sticks to the surface of the new blood vessels and since we just want to treat those fragile new vessels, light is shined into the diseased eye in the specific area. This activates the drug and destroys the new vessels at the macula.

With photodynamic therapy, there is a slower rate of vision decline, Dr Margius said, “and in some patients there can be up to three years more vision.”

“There are other means of treatment. These include a high daily dosage of vitamins with antioxidants and zinc: 500 mg of Vitamin C, 400 mg of Vitamin E, 15 mg of beta carotene — also labeled as the equivalent of 25,000 international units of Vitamin A — 80 mg of zinc oxide and 2 mg of copper or cupric oxide.”

He explained that there are three common commercial vitamin formulas that deliver these basic ingredients: ICaps, Visi Vite, and Ocu Vite.

“Be careful of beta carotene if you are a smoker. People who smoke and take beta carotene are at a higher risk of stroke. It might be better for them to eat an extra amount of leafy green vegetables and fruits.

“As for the new technology, they are still working on vitamins like lutein, which protects the macula, and zeaxanthin, which is part of the retina. But the jury is still out on these. They may be helpful, but so far the data is nonconclusive.”

 

Get Regular Eye Check-Ups

Dr Margius reminded his audience that smoking is a risk factor for both cataracts and macular degeneration, and “I advise you to use sunglasses to protect your eyes against the UV [ultraviolet] in sunlight.”

“Maintain a normal blood pressure, exercise, and follow a weight control regimen,” he added.

Lifestyle choices can possibly delay or mitigate the effects of cataracts or macular degeneration, Dr Margius said, but unfortunately, the progress of macular degeneration is not reversible.

As for frequency of check-ups, he recommended going to a doctor every other year beginning at age 50, and going every year after age 60.

Dr Margius offered audience members a list of email addresses for further study. The recommended websites were the following: National Eye Institute, www.nei.nih.gov; American Optometric Association, www.aoa.org; American Academy of Ophthalmology, www.aao.org; and Lighthouse International, www.lighthouse.org.