Nearsighted, farsighted or astigmatism? How to tell what you have

Most Filipinos describe their eyes in one of two ways: malabo ang malayo, or malabo ang malapit. Far things are blurry, or near things are. It turns out there is a third possibility, and it is the one most often missed.

All three are refractive errors. The eye is not bending light to land precisely on the retina. Where it lands, and why, is what separates them.

How a normal eye focuses

Light enters through the cornea, the clear dome at the front, then passes through the lens inside the eye. Both bend it so it converges to a sharp point on the retina at the back. Sharp point on the retina equals clear image.

Miss that point and you get blur. Refractive errors are simply the different ways of missing.

Myopia: nearsightedness

The eye focuses light in front of the retina, usually because the eyeball is slightly longer than average or the cornea is more steeply curved.

What it feels like: Close work is comfortable. Distance is not. Street signs, the whiteboard, the TV from the sofa, faces across a room. People squint at distance, sit closer to screens, and often discover it when they cannot read something everyone else can.

Myopia is the most common refractive error in the Philippines and it typically appears and progresses during school years. On a prescription it appears as a minus figure under SPH, and the further from zero, the stronger.

Hyperopia: farsightedness

Light focuses behind the retina, usually because the eyeball is slightly shorter than average.

What it feels like: This is where it gets confusing. Mild hyperopia often produces no blur at all in young people, because the eye's own focusing muscle compensates automatically. What you get instead is the cost of that compensation: eye strain, headaches after reading, tired eyes by late afternoon, and difficulty holding attention on close work.

Because distance vision is usually fine, hyperopia gets missed. Children with it are sometimes assumed to have a reading or concentration problem when the actual issue is that reading is physically tiring. On a prescription it appears as a plus figure under SPH.

Astigmatism

The cornea, or sometimes the lens, is not evenly curved. Instead of being shaped like a section of a ball, it is shaped more like a section of a rugby ball, curving more steeply in one direction than the other.

The result is that light focuses at two different points rather than one. Nothing is perfectly sharp at any distance.

What it feels like: Blur at all distances rather than at one. Letters look slightly doubled or shadowed. Lights at night stretch into streaks or starbursts, which is why night driving is the moment many people finally notice. Frequent squinting and headaches are common because there is no distance at which relaxing produces a clear image.

Astigmatism is very common and it usually coexists with myopia or hyperopia rather than appearing alone. On a prescription it appears as CYL and AXIS: the amount of the uneven curve, and the direction it runs.

Presbyopia is a different thing entirely

After about 40, near work gets harder for nearly everyone. That is presbyopia, and it is not a refractive error in the same sense. The lens inside the eye becomes less flexible, so it cannot change shape to focus up close.

The reason it matters here is that people confuse presbyopia with newly developed hyperopia. Both make reading hard. They have different causes and are corrected differently, and one arrives on a schedule while the other does not.

Why you cannot work this out yourself

You can get a rough sense of which category fits. What you cannot do is measure it, and measurement is the entire job.

Two people can both say distance is blurry and need very different prescriptions. Astigmatism requires an axis in degrees, not just an amount, and a few degrees off makes a lens that never feels quite right. Mild hyperopia can hide behind a young eye's focusing effort so effectively that only a proper refraction reveals it. And each eye is measured separately, because they are frequently different.

Online charts and phone apps do not measure any of this. They tell you something might be wrong, which you already suspected.

Get the measurement, then get the right lens

Book a Vision7 eye test at your nearest Vision Express store. Steps three and four of our seven-step exam are objective and subjective refraction: the instrument estimates your prescription, then the optometrist refines it with you until it is right. That is how you find out which of these three you have, in what combination, and in what amount in each eye.

If astigmatism turns out to be part of the picture, ask for Shamir Opulens Exact at the counter. It is cut to your own measurements, so the cylinder and axis land where they should rather than being approximated, which is what makes the difference between glasses that work and glasses that almost work. Made in Israel, seven to nine days.

If your prescription is strong and you are worried about thick lenses, ask about Tokai BIR-W, or Tokai HR-W for the thinnest option we carry. Made in Japan, ten to twelve days.

Every pair includes free lifetime ultrasonic cleaning, free lifetime custom fitting and adjustment, and a one-year warranty.