|
Age-Related Macular Degeneration (ARMD) is the leading cause of vision loss in older American adults and the most common reason patients are referred to Texas Retina Associates for further evaluation, treatment and care. Patients afflicted with ARMD may note a worsening of their central vision while retaining good peripheral vision.
Many patients with macular degeneration share a common misconception and fear that the disease will automatically progress to blindness. As suggested by its name, ARMD only affects the macula. The macula is the central part of the retina responsible for detailed visual tasks. In macular degeneration, patients suffer varying degrees of destruction to this tissue and can experience a wide spectrum of visual problems. These include, but are not limited to, blurred central vision, increasing difficulty with reading, patchy visual loss, and the distortion or warping of straight objects. However, even patients with advanced macular disease tend to retain excellent peripheral vision.
Back to top
Macular degeneration primarily affects older, white individuals, although cases have been reported in younger patients and those not of Caucasian descent. Additionally, a number of risk factors predispose certain people to the development and progression of the disease, including:
- Hypertension (high blood pressure)
- Cigarette smoking
- Having a family member with ARMD
Regarding the last risk factor, much research has been done regarding the genetics of macular degeneration. Although there is currently no way to definitively predict who will or will not develop ARMD, those with affected relatives are at significantly higher risk. As a result, adult relatives of ARMD patients should schedule an appointment with a retinal specialist and undergo a baseline evaluation and dilated exam.
Back to top
Generally, patients with ARMD are grouped into one of two categories-- those with dry macular degeneration and those with wet macular degeneration. Dry ARMD is characterized by thinning of the macula and gradual deterioration of vision. Wet ARMD is so called because it is marked by an accumulation of fluid underneath the retina. In contrast with dry macular degeneration, patients with wet ARMD often, but not always, experience sudden and severe visual losses.
Back to top
Dry and wet macular degeneration impact vision in different ways and are also treated quite differently. Sometimes it is difficult to differentiate between dry and wet ARMD so our physicians will use a variety of clinical tests and exam techniques to make an accurate diagnosis.
During an initial visit for macular degeneration, patients typically undergo two tests: Fluorescein Angiography (FA) and Optical Coherence Tomography (OCT). These tests may even be performed prior to consulting with a Texas Retina physician.
FA is considered the “gold standard” for differentiating between dry and wet ARMD. It involves the injection of a small amount of vegetable-based dye through a patient’s peripheral vein -- usually the arm or hand. Shortly after, a certified ophthalmic angiographer will take a series of time-dependent retinal photographs. The injected dye lights up the retina’s intricate vascular network and helps our specialists pinpoint a precise area of leakage in those patients with wet macular degeneration. Not only is this useful in determining the extent and progression of the disease, but it also helps when targeting specific treatment zones with specialized laser therapy.
OCT is a relatively new, non-invasive, quick exam that has gained universal acceptance during the last decade and is now used by many ophthalmologists. Using reflected light rays, OCT provides a detailed, highly magnified, cross-section view of a patient’s macula. Sometimes, it will uncover tiny areas of leakage not readily apparent to a retina specialist during a microscopic exam.
Back to top
Despite recent advances in ophthalmic imaging, there is no single test that can be relied upon to direct treatment and clinical decision-making. A patient’s relationship with his or her Texas Retina specialist is at the core of our practice philosophy, and good patient-physician communication is critical. When making important decisions about retinal health, it is very much a joint effort. The patient’s perception of his or her visual health and the patient’s perception of any vision changes, however slight, is every bit as important in directing care as are the clinical tests.
As a result, every patient diagnosed with macular degeneration should establish a daily routine for monitoring their own vision. This is most simply and reliably performed with an Amsler grid, a simple graph paper-like patchwork of straight vertical and horizontal lines, which we are happy to provide at no cost – simply ask one of our nurses.
Often, patients with subtle progression of macular disease will report new “waviness” or “missing areas” when monitoring their grid. Should you or a family member notice new changes on an Amsler grid, contact us promptly. One of our retina specialists or trained ophthalmic nurses is always available to consult with you by phone. As a general rule, patients who receive treatment in a more timely fashion tend to fare better than those who delay evaluation by a retinal specialist.
Back to top
Please refer to our companion handout for detailed information on the current range of available therapies
Medical researchers have thrown themselves fully into the battle against macular degeneration, and dramatic progress has been made in the effort to combat age-related vision loss. The most promising new treatments are Avastin and Lucentis which help block certain growth factors that are thought to cause “leaky” blood vessel growth in wet macular degeneration. Both of these medications are introduced directly into the eye through a tiny needle. While the thought of an “eye shot” might cause many to cringe, in our experience, there is little, if any, patient discomfort, and the spectacular visual gains far outweigh any fears.
Avastin and Lucentis are the first medicines that have actually improved vision for many patients with wet macular degeneration. While most retina specialists feel that both work equally well, this has yet to be proven in a large, nationwide, prospective clinical trial. One such trial (CATT) is now underway, and Texas Retina has been selected to be a part of this historical study. Should you have an interest in participating in this trial, please inform your retina specialist during your next visit.
While Avastin and Lucentis have received much media attention and deserved fanfare for their impact on wet ARMD, invaluable work continues on the dry ARMD front as well. A number of vitamin therapies are already available to slow the progression of dry ARMD, and Texas Retina is currently involved in a second-generation vitamin study that will hopefully prove even more beneficial than previously prescribed supplement regimens.
Back to top
|