👀 Macular Degeneration
Central vision goes, peripheral vision stays — the exact opposite of glaucoma. Dry vs wet, and what actually slows it.
🧬 What it is
The macula is the small central patch of retina that does detailed vision. Reading, faces, fine work — all macula.
So macular degeneration takes CENTRAL vision and leaves the periphery. Glaucoma does the reverse.
| Central vision | Peripheral vision | |
|---|---|---|
| Macular degeneration | LOST — blur or blank spot | Preserved |
| Open-angle glaucoma | Preserved until late | LOST — tunnel vision |
| Cataract | Whole field cloudy, glare at night | |
Patients can still walk around a room but cannot read or recognize a face. That functional split is exactly how exam questions describe it.
👀 Dry vs wet
| DRY (atrophic) | WET (exudative) | |
|---|---|---|
| Share of cases | ~85–90% | ~10–15% |
| Mechanism | Macular cells thin and atrophy; drusen deposits | New leaky vessels grow under the retina |
| Onset | Gradual, over years | Sudden, over days to weeks |
| Hallmark | Slow central blurring | Straight lines look wavy (metamorphopsia) |
| Treatment | Supplements, monitoring | Anti-VEGF injections into the eye |
Wavy or bent straight lines - door frames, tiles, text - is the sign of WET macular degeneration and needs urgent referral. It is treatable if caught early.
✅ The Amsler grid
A simple grid of straight lines with a central dot. The patient covers one eye, stares at the dot, and reports any wavy, missing or distorted squares.
Used daily at home — it is how conversion from dry to wet gets caught in time.
🩺 What helps
Risk factors you can change
- Smoking — the single biggest modifiable risk; roughly doubles it
- UV exposure — sunglasses and a hat
- Hypertension and cardiovascular disease
- Diet — dark leafy greens, fish; the AREDS-type supplement formulations
Unmodifiable: age over 60, family history, light-colored eyes.
🏠 Living with it
- Magnifiers, large print, high-contrast materials
- Bright, direct task lighting
- Teach eccentric viewing — looking slightly to the side of an object to use healthy retina
- Home safety: they retain peripheral vision, so mobility is usually fine, but reading medication labels is not
- Screen for depression — loss of reading and driving is a major life change
🎯 NCLEX traps
- Central loss, peripheral kept — opposite of glaucoma
- Wavy lines = wet = urgent
- Amsler grid is used daily at home, not just in clinic
- Smoking cessation is the top teaching point