Health Conditions

Geographic Atrophy

OverviewOverview

Geographic atrophy (GA) is an advanced form of dry age-related macular degeneration (AMD), a leading cause of irreversible blindness in older adults. GA leads to the gradual degeneration of retinal cells, resulting in the formation of blank or dark areas (atrophic lesions) in the central vision.

The condition is termed "geographic" because the affected areas of retinal atrophy appear on imaging to have well-defined, map-like borders. The progress of GA can be slow, and in its early stages, it might not cause noticeable symptoms. However, as the condition advances, it can significantly impact daily activities, such as reading, recognizing faces, and driving.

Risk Factors

Several risk factors contribute to the development of GA. Understanding these factors can help in the early identification and management of the condition.

Age: The risk increases significantly with age, particularly after 60 years.
Genetics: Certain genetic mutations can predispose individuals to AMD and GA.
Smoking: Tobacco use has been strongly linked to the development and progression of GA.
Diet: Poor dietary habits, especially those lacking in key nutrients like vitamins C and E, zinc, and lutein, can elevate the risk.
Cardiovascular Health: Conditions such as hypertension, high cholesterol, and obesity are associated with a higher risk of GA.

Causes

GA is primarily caused by the degenerative changes associated with age-related macular degeneration. The exact cause of geographic atrophy is not fully understood, but it is believed to result from a combination of genetic, environmental, and lifestyle factors.

Key contributors to the development of GA include:

Genetic mutations: Variations in certain genes associated with retinal health can increase susceptibility to GA.
Oxidative stress: Damage caused by free radicals can lead to the degeneration of retinal cells.
Inflammation: Chronic inflammation of the retina can contribute to cellular damage and atrophy.

Signs and Symptoms

The signs and symptoms of geographic atrophy can vary depending on the stage and severity of the condition. Initially, there may be minimal or no noticeable symptoms. As the disease progresses, individuals may experience:

Gradual loss of central vision.
Difficulty in seeing fine details, both up close and at a distance.
Dark patches or blank spots in the field of vision.
Enhanced difficulty in low-light conditions or night vision.
Distortion of objects (metamorphopsia) as the condition progresses.

Diagnosis and Tests

Diagnosis of GA typically involves a comprehensive eye examination by an ophthalmologist, utilizing several diagnostic tools and tests to ascertain the extent and progression of the condition.

Common diagnostic procedures include:

Fundus Autofluorescence: To capture detailed images of the retina to visualize the health of the retinal cells.
Optical Coherence Tomography (OCT): A non-invasive imaging test that provides cross-sectional pictures of the retina.
Fluorescein Angiography: Involves injecting a fluorescent dye to visualize blood flow in the retina.
Visual Field Testing: To determine the extent of vision loss or blind spots.

Treatments

Currently, there is no cure for GA, but several treatment options aim to slow its progression and help manage symptoms. Recent US Food and Drug Administration (FDA) approvals marked the first two therapies approved for GA secondary to AMD. Ongoing clinical trials are exploring new possibilities for treatment, including gene and cell therapies.

Complement inhibitors: The FDA has approved two drugs for the treatment of geographic atrophy: pegcetacoplan (Syfovre) and avacincaptad pegol (Izervay). Pegcetacoplan is a targeted C3 therapy that aims to slow the progression of the disease by inhibiting the complement system, which is part of the body’s immune response. Avacincaptad pegol, also a complement inhibitor, targets C5 and reduces inflammation and cell damage in the retina.
Vitamin and Mineral Supplements: Special formulations, such as the AREDS2 supplements, may help slow degeneration.
Low Vision Aids: Devices like magnifiers and special glasses can help enhance remaining vision.
Clinical Trials: Experimental treatments are constantly being tested for efficacy and safety.

Tips and Extra Resources

Managing GA requires a combination of medical intervention and lifestyle adjustments. Here are some tips and extra resources to help navigate this condition.

For more information and resources on geographic atrophy, consider visiting reputable websites and organizations dedicated to eye health, such as:

Latest News: Geographic Atrophy

Alyssa Westrate, O.D.: Why Year-End Vision Screenings Are Essential for Eye Health

Alyssa Westrate, O.D., explains that scheduling an eye exam before the end of the year can maximize insurance benefits and detect early vision or health issues, helping to maintain optimal eye health.