Lacquer cracks are breaks in Bruch’s membrane, a thin layer in the back of your eye. They’re mostly linked to high myopia but can show up in other conditions too.
What exactly breaks?
- Location: Bruch’s membrane sits between the retinal pigment epithelium (RPE) and the choroid. It’s like the “basement membrane” for the retina
- The crack: Think of paint on a wall. If the wall stretches too much, the paint develops hairline cracks. Same idea when the eyeball elongates in high myopia
- Appearance: On eye exams, they look like yellowish, irregular lines in the back of the eye, often near the macula
Main causes
- Pathologic myopia: Biggest cause. Eyes longer than 26.5 mm or stronger than -6.00D stretch Bruch’s membrane until it tears
- Trauma: Blunt injury to the eye can cause acute cracks
- Angioid streaks: Associated with systemic diseases like pseudoxanthoma elasticum, Ehlers-Danlos, Paget’s disease. Angioid streaks can develop lacquer cracks
- Choroidal neovascularization: Sometimes new blood vessels form around the cracks
Symptoms
- Often none early: Many people have lacquer cracks with no vision change
- If macula involved: Blurred vision, distorted vision where straight lines look wavy, or a blind spot
- Sudden vision drop: Usually means a complication like bleeding or CNV has started
Complications to watch for
- Choroidal neovascularization (CNV): New, leaky blood vessels grow through the crack. This is the main threat to vision and can cause bleeding/scarring
- Subretinal hemorrhage: Blood under the retina from CNV, causes sudden central vision loss
- Fuchs’ spot: Pigmented scar that forms after a bleed heals. Leaves permanent central scotoma
How doctors diagnose
- Dilated fundus exam: Doctor sees yellow lines
- OCT scan: Shows the break in Bruch’s membrane and any fluid/blood
- Fluorescein angiography: Dye test to check for CNV leaking through the crack
- ICG angiography: Better for seeing deeper choroidal vessels
Treatment
- No fix for the crack itself: Bruch’s membrane can’t be stitched back. Goal is to manage complications
- If CNV develops: Anti-VEGF injections like Avastin, Lucentis, or Eylea into the eye to stop new vessels
- Monitor: Regular OCT scans if you have lacquer cracks, especially with high myopia
- Lifestyle: No proven way to prevent them, but controlling myopia progression in kids may help reduce future risk
Who’s at risk
- High myopes: -6.00D or worse, or axial length >26.5 mm
- Age: Usually appears in 20s-40s in myopic patients
- Family history: Pathologic myopia runs in families
Bottom line: Lacquer cracks themselves don’t always hurt vision. The danger is when new blood vessels grow through them. If you have high myopia, get yearly dilated eye exams so any CNV gets caught early.