Age Related Macular Degeneration ( ARMD / AMD)

1. Dry Macular Degeneration (non-neovascular).

Dry AMD is an early stage of the disease. Gradual central vision loss may occur with dry macular degeneration but usually is not nearly as severe as wet AMD symptoms. However, dry AMD through a period of years slowly can progress to late-stage geographic atrophy (GA) — gradual degradation of retinal cells with accumulation of cellular debris called drusen also can cause severe vision loss. Nutritional supplements containing antioxidants and multivitamins that contain lutein & zeaxanthin can reduce the risk of dry AMD progressing to sight-threatening wet AMD.

Currently, the best way to protect your eyes from developing early (dry) macular degeneration is to eat a healthy diet, exercise and wear sunglasses that protect your eyes from the sun’s harmful UV rays and high energy visible (HEV) radiation.

2. Wet Macular Degeneration (neovascular).

In about 10 percent of cases, dry AMD progresses to Wet macular degeneration. With wet macular degeneration, new blood vessels (choroid new vessels CNV) grow beneath the retina and leak blood and fluid. This leakage causes permanent damage to light-sensitive retinal cells, which die off and create blind spots in central vision. Wet macular degeneration falls into two categories:

Occult form.New blood vessel growth beneath the retina is not as pronounced, and leakage is less evident in the occult CNV form of wet macular degeneration, which typically produces less severe vision loss.

Classic form.When blood vessel growth and scarring have very clear, delineated outlines observed beneath the retina, this type of wet AMD is known as classic CNV, usually producing more severe vision loss.

Symptoms of macular degeneration:

• Blurred or distorted central vision
• Colours look dim
• Words on a page look blurred
• Straight lines appear distorted (Amsler-Grid Chart)
• Dark or empty areas appear in the center of vision

This makes activities like reading, writing and recognizing small objects or faces very difficult.

An Amsler grid consists of crossed straight lines, with a reference dot in the center. Someone with macular degeneration may see some of the lines as wavy or blurred, with some missing / dark areas at the center.If your eye doctor detects some defect in your central vision, such as distortion or blurriness, he or she may order a fluorescein angiography to examine the retinal blood vessels surrounding the macula.

HOW IS MACULAR DEGENERATION DIAGNOSED?

Viewing the macula with dilated pupils with 90D / 78D lens and slit-lamp.

Spectral OCT, FFA (Fundus Fluorescein Angiography) is done to find fluid / abnormal blood vessels under the macula. Indocyanine green angiography is done in certain cases.

TREATMENT

a) TREATMENT OF DRY MACULAR DEGENERATION

• Nothing much can be done in Dry AMD except regular eye tests by the Ophthalmologist and regular Amsler Grid self test by the patient. Any increase of distortion on the Amsler Grid is to be reported immediately.
• Avoidance of smoking and having a healthy diet along with diet supplements containing lutein and zeaxanthin increase the density of pigments in the macula that are associated with protecting the eyes from AMD.
• L.V.A. - low vision aids like magnifying glasses, telescopic spectacles or closed-circuit televisions is used in the dry form to help the person improve his central vision .

b) TREATMENT OF WET MACULAR DEGENERATION / CNV

For Wet AMD treatment is aimed at stopping CNV, abnormal blood vessel growth with drugs called Anti-VEGF which include Lucentis, Accentrix, Macugen, Avastin etc. These are given as intravitreal injection into eyes of patients with Wet AMD with good results . Most patients will retain the vision they have and some will regain some of the lost vision after this treatment. The injections may need to be repeated on fixed intervals or as per response.

Lucentis, Accentrix eye injections & the colorectal cancer treatment drug Avastin work by inhibiting proteins called vascular endothelial growth factor (VEGF), which stimulate the growth of new blood vessels in the retina . Macugen uses a therapeutic molecule to attack VEGF in the eye.

Visudyne drug treatment (Photodynamic Therapy or PDT). Visudyne was the first drug therapy approved for treatment of the wet form of macular degeneration. It is only for those patients who have new blood vessel growth (neovascularization) under the retina in a well-defined, distinctive pattern known as "predominantly classic." About 40 to 60 percent of new wet AMD patients have this form of the disease .

TTT & Laser treatment. Laser photocoagulation is another macular degeneration treatment for wet AMD. The procedure uses laser light to destroy or seal off new blood vessels to prevent leakage. A major drawback of laser photocoagulation in such cases, however, is that it produces many small retinal scars, which cause blind spots in the patient's visual field. For this reason, the laser procedure is no longer widely used to treat AMD.

For wet AMD, treatments aimed at stopping abnormal blood vessel growth include drugs called AntiVEGF drugs Lucentis, Accentrix, Macugen and Avastin are given as intravitreal injection into Eye in patients with Wet AMD with good results by Vitreoretinal surgeon .

LOW VISION AIDS :

Many options are available at our hospital for patients who have advanced AMD damage or very poor vision due to various reasons. A Fresnel sheet magnifier is given free to patients who have both eyes intra-vitreal Lucentis / Accentrix injection along with complete ARMD tests at our hospital.