Macular degeneration is a common condition that develops in the sixth decade of life, and can progress in a subset of individuals to affect central vision--affecting one’s ability to read, recognize faces, and drive. Routine eye examinations and prompt treatment may lessen the chance of permanent vision loss in some, and yet in others, limitations of current treatments and/or the natural progression of the condition can lead to vision loss.
What is macular degeneration?
A complex interplay of age, environment, genetics, and the innate immune system lead to abnormal deposits underneath the retina called drusen. This abnormal deposition can progress to atrophy of layers underneath the retina necessary to support normal vision, or to growth of blood vessels called choroidal neovascular membranes that can hemorrhage or fibrose affecting central vision. When choroidal neovascular membranes develop, this is referred to as exudative or wet macular degeneration. When these membranes are not present, the condition is referred to as non-exudative or dry macular degeneration.
What causes macular degeneration?
Abnormal deposition of protein/lipid under the retina occurs with age, and more commonly in those of European ancestry. Factors, like poor nutrition and smoking can worsen this condition, as can genetic factors that modulate the function of one’s innate immunity. Innate immunity has been ascribed a larger role in damaged tissue removal, and since removal of diseased tissue within and underneath the retina is not replaced due to lack of regeneration capacity, vision loss can ensue.
What are the symptoms of macular degeneration?
This varies from no symptoms to severe loss of central vision. Some will note blurry vision or central visual distortion (metamorphopsia). The course of vision loss can indicate the type of macular degeneration, where the wet macular degeneration is often marked by sudden development of metamorphopsia or central vision loss, and the dry type, by slow or gradual vision loss.
How is macular degeneration diagnosed?
A dilated eye exam utilizing hand-held lenses, optical coherence tomography of the retina, fundus photography, and fluorescein angiography may be used in combination to identify and/or evaluate the condition.
What are the treatments for macular degeneration?
Vitamin supplements with AREDS2 vitamins can slow the progression of the condition iin those with intermediate stages of macular degeneration. Angiogenesis inhibitors are the first-line treatment for the wet type of macular degeneration, and are administered in the office setting with a local anesthetic. Laser treatment can cause a regression of choroidal neovascular membranes, but is no longer first-line therapy. Vitrectomy with injection of a thrombolytic under the retina may be utilized if a substantial hemorrhage occurs from a choroidal neovascular membrane. Blocking the complement cascade has shown positive results in lessening progression of atrophy in advanced dry macular degeneration, but is still a subject of clinical trials assessing safety and efficacy.