Patient will present as → a 62-year-old male who arrives for his follow-up visit for chronic, gradual central vision loss. He describes a phenomenon of wavy or distorted vision that has deteriorated rather quickly. The patient is frustrated because he "just can't drive anymore,” and he is "having difficulty seeing words when he reads.” When looking at a specific region of the Amsler grid, he reports a dark “spot” in the center, with bent lines. On the fundoscopic exam, you note areas of retinal depigmentation along with the presence of yellow retinal deposits.
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Gradual PAINLESS loss of CENTRAL vision (versus glaucoma, which presents with a peripheral → central loss)
- The macula is responsible for central visual acuity, which is why macular degeneration causes gradual central field loss
- Macular Degeneration is the most common cause of permanent legal blindness and visual loss in the elderly > 75
- Dry macular degeneration (85% of cases): atrophic changes with age – slow, gradual breakdown of the macula (macular atrophy), with DRUSEN (DRY)= yellow retinal deposits
- Wet macular degeneration: an advanced form of dry age-related macular degeneration. New blood vessels growing beneath the retina (neovascularization) leak blood and fluid, damaging the retinal cells. These small hemorrhages usually result in rapid and severe vision loss
Dilated funduscopic findings are diagnostic; color photographs, fluorescein angiography, and optical coherence tomography assist in confirming the diagnosis and in directing treatment.
- Wet - Age-Related Macular Degeneration - hemorrhage or fluid in the subretina
- Neovascularization: macular grayish-green discoloration
- Dry - Age-Related Macular Degeneration
- Drusen deposition
- areas of retinal atrophy (depigmentation)
- retinal pigment epithelium mottling (pigmentation)
- Amsler grid: line distortion seen on the grid
Normal Amsler Grid
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Amsler grid as it might be viewed by a person with age-related macular degeneration
Wet Age-Related Macular Degeneration
- VEGF inhibitors (e.g., bevacizumab)
- Photodynamic therapy
- Zinc and antioxidant vitamins
Dry Age-Related Macular Degeneration
- Zinc and antioxidant vitamins
Age-related macular degeneration (AMD) is the most common cause of irreversible central vision loss. It affects patients over 60 years of age and is related to retinal aging. There are two types: dry (nonexudative) and wet (exudative). Dry AMD accounts for the majority of the diagnoses of the condition, while wet AMD is the more severe form. Prolonged exposure to UV light, smoking, lighter colored eyes, and hyperopia are risk factors.
Play Video + QuizQuestion 1 |
Night vision Hint: Night vision is a function of rod photoreceptors, which are found in the peripheral retina. | |
Color vision Hint: Color vision is a function of cone photoreceptors | |
Peripheral vision Hint: The peripheral retina is responsible for peripheral vision. | |
Central vision acuity |
Question 2 |
Glaucoma Hint: Glaucoma occurs in about 6% of diabetics. Neovascularization of the iris can cause closed angle glaucoma. | |
Cataracts Hint: Cataracts can occur secondary to diabetes, but are not caused by proliferative retinopathy. | |
Vitreous hemorrhage | |
Optic neuritis |
Question 3 |
Blepharitis Hint: Blepharitis is a chronic bilateral inflammatory condition of the lid margins | |
Cataracts Hint: Cataracts are the clouding of the lens sufficient to reduce vision. Most develop slowly as a result of aging, leading to gradual impairment of vision. | |
Central retinal artery occlusion Hint: Central retinal artery occlusion presents as a rare cause of sudden profound monocular visual loss. | |
Macular degeneration |
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List |
References: Merck Manual · UpToDate