A decade of vision loss in a few seconds of scrolling
Keratoconus affects an estimated 1 in every 300 people, though the exact prevalence is unknown. And it is possible not to know you have it for years, even as vision loss occurs. Scroll to see a representation of it. NKCF
A scroll-driven photograph below simulates keratoconus vision: as the page scrolls, the image warps, halos bloom around lights, ghosted copies overlay the scene, and detail blurs in ways that glasses cannot correct. A plain-text description of the condition follows further down the page.
Another look
Seeing it another way
That simulation was an approximation. Here's another attempt from during my recovery from corneal cross-linking surgery.
Two scatter plots are crossfaded as you scroll. With normal vision, every data point is a single dot. With the author's vision while recovering from corneal cross-linking surgery, the same plot appears with every data point tripled into three overlapping dots.
The condition
When the cornea stops holding its shape
Keratoconus (KC) is a progressive disorder where the cornea, normally a dome, gradually thins and bulges outward into a cone shape (hence the name). As it distorts, it bends light incorrectly, causing blurred and distorted vision that worsens over years. NKCF Mayo Clinic
It typically begins in the late teens or early twenties and can progress through the thirties. In severe cases, a corneal transplant becomes the only option. Caught early, specialty contact lenses and corneal cross-linking can slow or halt progression. Mayo Clinic NKCF
What it feels like
Symptoms of keratoconus
Ghosting & doubling
Multiple ghost images overlay a single object, especially under bright light. NKCF
Halos & streaks
Light sources bloom into starbursts and smeared streaks at night. NKCF
Blur that glasses can't fix
Standard prescriptions stop correcting vision as the cone shape progresses. NKCF
Light sensitivity
Oncoming headlights, screens, and sunlight become overwhelming and painful. NKCF
Frequent prescription changes
Rapid shifts in astigmatism that no single pair of glasses keeps up with. NKCF
Eye rubbing
Chronic itching leads to rubbing; associated with accelerated corneal thinning. NKCF
Take action
Early diagnosis changes everything
No website can diagnose eye diseases. If any of this looked familiar, talk to your eye doctor.