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Eye Examination for ARMD: Macular Degeneration

When You Need Eye Exam for Macular Degeneration. Randall Wong, M.D., Retina specialist, Fairfax, Virginia. Routine eye examinations for macular degeneration in patients without symptoms are probably not necessary.

Unlike conditions such as diabetic retinopathy, where the disease is likely to occur yet still be asymptomatic, macular degeneration is not “silent” and does have associated symptoms.

Once diagnosed with macular degeneration; however, routine examinations are important.

Family History Does Not Matter

While it is true that patients of northern European descent have a greater chance of developing the eye degeneration, brothers and sisters and children of patients with the disease are not necessarily at any higher risk.

For example, if I contract the disease, my twin brother is not necessarily going to get the disease.

Vision Must “Degenerate”

The most common symptoms of macular degeneration are decreased vision (e.g. blurry vision) and/or the development of distortion. Both signify a change in vision.

Without a change in vision, that is, if your vision remains 20/20 it is unlikely you have ARMD.

Signs vs. Symptoms of ARMD

Signs of a disease are those things we, as doctors, see or find during an examination. If you have no signs of macular degeneration, you do not have it.

For instance, drusen and pigment changes in the retina are common signs, or findings, of dry macular degeneration. Fluid, edema and blood are common findings of wet ARMD.

Pigment changes, fluid and blood may cause blurry and distorted vision….symptoms (subjective, what the patient experiences) of macular degeneration.

Often, patients are diagnosed with drusen. Drusen alone, especially without loss of vision, do not make the diagnosis of macular degeneration.

Advancing Age and Macular Degeneration

The National Eye Institute has a nice review of macular degeneration. The incidence of developing macular degeneration does increase with age. This means the chance of getting the disease does increase with age, but not without signs and symptoms.

What Does This Mean?

In short, unlike diabetic retinopathy, a disease that may develop without symptoms, you can safely monitor yourself for any symptoms of the ARMD, regardless of ethnicity, age or family history.

If you develop symptoms of decreased vision or if you develop decreased vision you should get an eye exam. Often, patients are directed to test themselves with an Amsler Grid. This is a simple way to monitor changes in your vision.

If you have signs of the disease, for example, drusen and changes in the retina, you might ask your doctor about getting examinations on a routine basis. This will be more important in the future if/when we discover changes in our diet or behavior (i.e. quitting smoking) alter the course of developing the disease.

If you have neither symptoms nor findings, you most likely require exams periodically as directed by your doc.

You Look All Bent Out of Shape

Distortion, also known as metamorphopsia, is a symptom of many macular diseases. Anything that affects the macula can cause distortion; epiretinal membranes, macular holes, macular edema, diabetic retinopathy and macular degeneration. The macula is a place in the retina, the functional center. Thus, the term “macular” becomes an adjective when describing retinal disease located in the center of the retina.

OCT scan of a retina at 800nm with an axial re... — Image via Wikipedia

The macula is a small area of the retina measuring about 1.5 x 1.5 mm. It is very sensitive and allows us our best color vision and the ability to see 20/20. A normal macula (fovea) is smooth and slightly concave (see OCT). Light falls on the normal macula giving us vision. This is very similar to a projector focusing images onto a movie screen. If there is a physical change to the macula or disease, central vision is usually affected.

Macular Pucker or Epiretinal Membranes

Epiretinal membranes are, as the name implies, membranes that develop on the surface of the retina and cause the underlying retina to wrinkle, or “pucker.” This physical wrinkling of the macula causes decreased vision and distortion.

Surgically removing the membrane usually improves the distortion and can improve the vision, too.

Macular Holes

If you were to poke a pin through a piece of ballon and then stretch out the rubber, you’d create a nice round hole. A macular hole is actually a stretch hole in the center of the macula. Images that fall within this hole are not seen as there literally is no retina in the center of the macula.

Symptoms include decreased vision, distortion and sometimes, scotomas, which are the fancy name for blindspots.

Macular Edema

Swelling of the macula can occur from a variety of causes. The two most common causes germaine to this web site are diabetic retinopathy (more specificially, diabetic macular edema) and swelling secondary to choroidal neovascularization in cases of wet macular degeneration.

Other causes, however, include central serous retinopathy, central and branch vein occlusions, cystoid macular edema from cataract surgery (uncommon these days) and from cases of intraocular inflammation (aka uveitis).

Macular Degeneration Causes Distortion 3 Different Ways

As above, choroidal neovascularization can physically distort the retina and cause distortion. These abnormal blood vessels can develop in between the layers of the retina causing physical disruption of the retina. The analogy here is exactly like the “Princess and the Pea.”

Wet macular degeneration can also cause macular edema as we discussed above.

Dry macular degeneration can also cause symptoms of distortion. One of the layers of the retina, called the RPE, becomes diseased and degenerates. This loss of one of the principle layers of the retina can cause distortion.

What Does This Mean? Distortion, or metamorphopsia, can be a symptom of a variety of retinal or macular disorders, not just macular degeneration. The key for saving your sight is early detection and diagnosis. Usually this may require consultation with a retina specialist to discuss the various treatments.

A fluorescein angiogram and/or an OCT (Optical Coherence Tomography) may be very helpful to your doctor, but this can vary.

Other causes of metamorphopsia, not related to the retina, could include large amounts of astigmatism or a decentered lens.

While most causes are indeed retina related, it is also important to note that most have a treatment with the exception of dry macular degeneration. There is some rumbling; however, that there may be some promising treatments for dry macular degeneration in the near future.

Testing Your Eyes at Home

The major problem with wet macular degeneration is that the “wet” abnormal blood vessels tend to affect the macula. This usually causes decreased vision and distortion. Home monitoring, or self-monitoring, is based on the premise that new distortion may signify presence of neovascularization.

Patients with wet macular degeneration have two major concerns; recurrence in the same eye and wet macular degeneration developing in the other eye. To alleviate their fears, doctors have long been recommending home monitoring as a method to catch the disease as early as possible.

Distortion from “wet” macular degeneration is similar to the “Princess and the Pea,” where the abnormal vessels are trying to sandwich themselves between the layers of the retina. This causes the retinal surface to become uneven which translates into distortion.

Amsler Grid Testing – The Amsler Grid is used on a daily basis, testing each eye separately. In this way, a patient with macular degeneration will become familiar with their own pattern of distortion. Any new waviness should be reported to their doctor. This may be a sign of active “wet” macular degeneration.

An electronic version of the Amsler Grid is available at “MyVisionTest.com.” There is also a link on the left side panel if you ever forget.

The ForSeeHome™ AMD Monitor is the first telemedicine device for the home. According to the company web page, this device offers self-monitoring of patients with known macular degeneration. It is not a diagnostic tool, but monitors changes in distortion. This information can then be transferred to the eye doctor for review. The device has received FDA “510(k)” clearance.

What Does This Mean? The idea of self-monitoring is to catch the “wet” form as early as possible. Early detection of wet macular degeneration usually translates to a better outcome. In my experience patients with wet macular degeneration are pretty motivated to self-test regularly and the Amsler Grid seems to be a very good, cheap, and reliable test. Remember that the macula is very sensitive and any change in distortion is usually pretty obvious.

It seems that a new telemedicine device might be “overdoing” it, at least from what I can tell from the web page and the press release. It does not make a diagnosis and examination by the doctor is still necessary.

I see three scenarios; however, where this might be useful; 1) a patient is unable to tell, himself, if there are changes in his own vision (yes, it happens), 2) a patient’s vision is so poor that subtle changes are unnoticed and 3) the device picks up earlier changes than can be noticed by the average individual, that is, the device is super-sensitive.

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax, Virginia

How To Tell if You Have Macular Degeneration

What are the symptoms of macular degeneration? Most patients have blurry vision and distortion. Macular degeneration is usually a bilateral disease (both eyes are involved) and is progressive, thus, symptoms are usually in both eyes and progress over time. The symptoms of blurry vision usually are persistent (they don’t come and go) and occur gradually.

Symptoms of patients with the “wet” or exudative form are slightly different and develop faster. Patients with wet macular degeneration may develop distortion and blurry vision in terms of weeks rather than losing visiong over months or years. In no case do patients go blind overnight. Unlike the dry form, patients with wet macular degeneration may complain of a dark, central grey spot.

What is the Amsler grid used for? An Amsler grid is used to self monitor. It can be placed in a common area in the home such as a refrigerator door or vanity mirror in the bathroom. Testing/ monitoring should be done frequently, perhaps daily. It is ideal in patients that already have some mild distortion. New, persistent distortion should be reported to your doctor.

When to call the doctor? If you notice a change in vision, including distortion, that is persistent, I recommend calling your eye doctor and scheduling an appointment. Symptoms that are transient (come and go during the day) are less likely to be related to the retina, but if concerned, you should call your doctor.

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retinal Specialist
www.TotalRetina.com

Do Macular Degeneration Patients Really Need Eye Exams?

Macular degeneration is a disease that affects the central vision. Wet or dry, it leads to progressive loss of vision. But how useful are regular examinations to detect and prevent damage to your central vision?

But first, some history. Macular degeneration comes in two flavors, exudative (wet ARMD) and non-exudative (dry ARMD). It usually affects both eyes in patients over 55 and is found in patients of northern European descent. There is no cure or treatment for the dry ARMD. Exudative, or wet, ARMD is defined by the presence of abnormal leaky blood vessels that develop within the layers of the retina. Wet ARMD is treated with PDT, Macugen®, Lucentis®, Avastin® and/or steroids, but there is no cure.

Reasons to have regular examination would be to check your vision and examine for signs of progression or development of the wet form. I would like to add that 80-90% of all patients with macular degeneration have the dry form. There is nothing to do for the dry form, nothing. I also think that it is a rare event for a patient to have the dry form and convert to the wet form. (If you feel I am wrong, please feel free to comment.)

Reasons not to have a regular eye examination if you have macular degeneration are the high likelihood there is nothing to do, especially if you have no new symptoms, or you have already lost significant vision in both eyes. This may sound a bit harsh and counter-intuitive, but going to the doctor only to hear me say what you’ve already heard, “you don’t see well and there is nothing to do” starts to be monotonous and depressing. It’s like going to your primary care doctor just for him/her to tell you that you are fat. Who wants to hear this stuff?

What I would do and what I tell my patients is that it is highly unlikely that I (as a doctor) will find anything treatable by scheduling routine examinations. Amsler grid testing is worthwhile (as long as you don’t over do it), but make sure to call or come if you notice a sudden change in vision, including new distortion, that is persistent more than a day. Some slight change that remedies itself after a few minutes doesn’t count, but something that lasts for a day or two straight merits attention. Retinal disease does not fluctuate from minute to minute.

As a physician, I’d like to add a couple of thoughts; 1) AMD is a tough disease, but in many cases, patients with wet AMD can be helped in many cases as especially if we treat you early, 2) AMD is a tough disease because many times there isn’t anything to do and the best we can do is keep status quo. 3) AMD is a tough disease because it ravishes the sight and many times there isn’t anything to do, but we gotta check and make sure.

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
www.TotalRetina.com

Tag Archives: distortion

Eye Examination for ARMD: Macular Degeneration

Family History Does Not Matter

Vision Must “Degenerate”

Signs vs. Symptoms of ARMD

Advancing Age and Macular Degeneration

You Look All Bent Out of Shape

Macular Pucker or Epiretinal Membranes

Macular Holes

Macular Edema

Macular Degeneration Causes Distortion 3 Different Ways

Testing Your Eyes at Home

How To Tell if You Have Macular Degeneration

Do Macular Degeneration Patients Really Need Eye Exams?

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