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October 31, 2026
Eye pressure usually reads lower after LASIK or PRK because surgery leaves the cornea thinner, flatter and less stiff. Standard tests then under-read the true pressure inside the eye [1,2]. In a 2026 review of 54 studies, the common Goldmann test read about 3 points (mmHg) lower after LASIK and about 2 points lower after PRK [3]. A falsely low number can hide high pressure or glaucoma, so tell every eye doctor about your surgery and keep your records from before it.
Key takeaways
In this article
This article is general education. It cannot tell you what your own pressure reading means. Use the urgent care list below if you have sudden symptoms.
Some symptoms should not wait for your next scheduled check. Tell any doctor you see that you had laser vision correction and whether you are using steroid drops.
See our guides to eye emergencies and angle-closure glaucoma warning signs.
Most eye pressure tests work by pressing on, or puffing air at, the cornea. LASIK and PRK remove corneal tissue, which leaves the cornea thinner, flatter and less stiff. A softer, thinner cornea gives way more easily, so the test reads lower even though the pressure inside the eye has not dropped by the same amount [1,2].
The standard test is Goldmann applanation tonometry. It measures the force needed to flatten a small spot on the cornea, and it assumes a cornea of typical shape and thickness [1]. Laser vision correction breaks that assumption.
In LASIK, the surgeon makes a thin flap and reshapes the tissue underneath. In PRK, the surface layer is removed and the laser reshapes the cornea from the top, with no flap [13]. Both change the cornea's thickness, shape and stiffness. In one LASIK study, two measures of how the cornea resists and absorbs force fell by 16% and 29% [2]. SMILE, a newer flapless laser procedure, also lowered readings [6].
On average, about 2 to 3.5 points. A 2026 review of 54 studies with 4,730 eyes found Goldmann readings about 3.2 mmHg lower after LASIK and 2.0 mmHg lower after PRK. The Corvis ST, an air-puff device that models corneal stiffness, showed smaller drops [3]. Individual eyes vary a lot around these averages.
The lower readings last. In one study that followed eyes for a year, Goldmann readings stayed about 3.5 mmHg lower after LASIK for nearsightedness and 1.4 to 1.9 mmHg lower after PRK. The drop was about 1 mmHg after LASIK for farsightedness [5].
The error is also uneven. In a study of 100 people who had LASIK, the higher a person's pressure was before surgery, the more it was under-read afterward [4]. That is the wrong way round for safety. The eyes that most need an accurate number are the ones most likely to be under-read.
No. The lower number mostly reflects a changed cornea, not a healthier eye. LASIK and PRK are not glaucoma treatments. Many people who have them were nearsighted, and nearsightedness itself is linked with higher glaucoma risk, so regular checks still matter [1,14].
Studies of this problem compare readings before and after surgery. No routine clinic test measures the true pressure inside the eye directly [1]. So doctors treat any post-surgery reading as an estimate.
If you were very nearsighted before surgery, the long shape of your eye has not changed. Our guide to high myopia complications explains why your original prescription still matters.
Because the error is not the same in every eye. It depends on the starting pressure, how much tissue was removed, corneal curvature and stiffness. Many correction formulas exist, but a 2020 review found that most were tested in few patients and several need old surgical records [1,4].
Simple charts that add points for a thin cornea assume thickness explains the whole error. After surgery, curvature and stiffness change too [1]. A formula may also work in the group it came from and less well in yours.
A correction can be one useful clue. It should not replace the optic nerve exam, nerve scans and visual fields. Never add points to your own reading or use an online chart to change treatment. For background on normal ranges, see our guide to eye pressure (IOP) readings.
No test is perfect after LASIK or PRK. In several studies, dynamic contour tonometry and the Corvis ST corrected reading changed the least after surgery, while standard Goldmann readings dropped more. Using the same method over time, and recording which one was used, helps make trends meaningful [2,3,5,6].
| Test | What studies found after LASIK or PRK |
|---|---|
| Goldmann applanation (standard) | About 3.2 mmHg lower after LASIK and 2.0 mmHg lower after PRK on average [3] |
| Non-contact air puff | Also under-reads after LASIK, more so in eyes with higher pressure [4] |
| Ocular Response Analyzer | Still reads lower; pooled drops were about 2.1 mmHg after LASIK and 2.5 mmHg after PRK [2,3] |
| Corvis ST, biomechanically corrected reading | Smallest pooled drop; among the least affected in a study of LASIK, SMILE and PRK [3,6] |
| Dynamic contour tonometry (Pascal) | Little or no change after LASIK and PRK in several studies [2,5,6] |
| Readings taken off-center (Goldmann or Tono-Pen) | After PRK, readings near the edge were about 2 mmHg higher than central ones [15] |
Not every clinic has every device. If two methods disagree, your doctor will weigh them against your nerve and field results. Disagreement is a reason to look closer, not to pick the most reassuring number.
Yes. Steroid drops calm inflammation during healing, but in some people they raise eye pressure. In a study of 506 eyes after PRK, 7.9% developed high pressure, starting 2 to 12 weeks after surgery. Pressure returned to normal in all of them after the steroid was stopped and pressure-lowering drops were started [7].
A "milder" steroid is not risk-free. In a trial of 300 eyes after PRK, pressure reached 22 mmHg or more in 2% of eyes on fluorometholone, 12% on betamethasone and 16% on loteprednol [16]. The authors of the 506-eye study suggested checking pressure no later than 10 to 14 days after steroids start [7]. Steroid drop labels advise monitoring pressure if the drops are used for 10 days or longer [12].
Serious harm can happen. A case report described permanent glaucoma vision loss after intensive steroid treatment for corneal haze after PRK [17]. Falsely low readings after refractive surgery can make a steroid response harder to spot [18].
Do not stop, restart or extend steroid drops on your own. Keep every follow-up visit, even if your eyes feel fine. Tell your surgeon before surgery if you have glaucoma, high eye pressure or a past pressure rise from steroids. Our page on high eye pressure explains other causes.
In some cases, a steroid-induced pressure rise after LASIK pushes fluid into the space under the flap. That fluid makes the central cornea read normal or low on Goldmann tonometry while the true pressure is high. In one series of six eyes, the high pressure was found only by measuring away from the center, sometimes after months [8].
All six eyes in that series developed visual field defects. Three had severe glaucoma damage and lost sharpness of vision [8,19]. Doctors call this problem pressure-induced stromal keratopathy (PISK) [20].
PISK can look like diffuse lamellar keratitis, an inflammation under the flap that is treated with more steroid. PISK is the opposite. It improves only when steroids are stopped and pressure is lowered [20]. That is why worsening haze while on steroid drops needs a prompt exam, not a guess.
Keep your pre-surgery eye pressure readings and the device used, corneal thickness, corneal curvature (keratometry) readings and your original glasses prescription. Add the amount of correction treated and the surgery type and date. Many correction methods use these numbers, and cataract surgeons use special lens-power formulas for eyes that had laser surgery [1,21].
If you do not have these records, ask the original clinic for copies. If they are gone, care can still go on. Your eye doctor can set a new baseline with nerve scans and visual fields.
Doctors lean more on the optic nerve and visual field than on the pressure number. Glaucoma is damage to the optic nerve, found with a dilated eye exam that includes a visual field test. Early glaucoma usually causes no symptoms, so regular checks matter even when your vision is sharp [10].
A visual field test checks your side vision. Clear central vision after LASIK says nothing about it. OCT scans measure the nerve fiber layer around the optic nerve. Repeating the same tests on the same devices shows whether anything is changing. Our guide to glaucoma tests: pressure, OCT and visual fields walks through each one.
Glaucoma treatment lowers eye pressure to slow damage [10]. If you are treated, your target pressure should take your surgery into account. Ask your doctor how your readings are being interpreted.
There is no simple yes or no. It needs a careful, individual decision with both your glaucoma doctor and your refractive surgeon. The main concerns are the steroid drops used afterward, which can raise pressure, and the lower readings that make later monitoring harder [3,18]. Your glaucoma care should continue unchanged after any surgery.
If you already had surgery and have glaucoma, keep using your glaucoma eye drops unless the doctor managing your glaucoma changes them. Clear vision does not mean the glaucoma is gone. When the surgeon and glaucoma doctor are different people, agree on who checks pressure during recovery. For problems such as dryness, glare or ectasia after surgery, see our page on failed LASIK surgery.
Netra Restoration Therapy (NRT) is an acupuncture and Oriental medicine approach offered alongside care from your eye doctor. It does not measure or lower eye pressure and does not diagnose glaucoma. NRT has not been tested in controlled trials for glaucoma after LASIK or PRK. It should never delay or replace pressure checks, nerve scans, visual fields, drops, laser or surgery.
Read what NRT involves and how Netra discusses NRT effectiveness.
The main glaucoma risks around LASIK come from steroid drops used during healing, which raise pressure in some people, and from lower readings that can hide high pressure later. In some reported cases, a steroid pressure rise with fluid under the flap caused severe glaucoma damage. Regular checks and telling every eye doctor about your surgery help catch problems early.
Yes. PRK has no flap, but it still thins and reshapes the cornea. On average, standard Goldmann readings are about 2 mmHg lower after PRK. Steroid drops used after PRK can also raise true pressure in some people.
There is no separate normal range after LASIK. Because standard readings run about 3 mmHg lower on average, a reading that looks normal may hide a higher true pressure. Your doctor judges it against your pre-surgery readings, your optic nerve and your visual field.
Yes. Steroid drops after surgery can raise pressure in some people, and glaucoma can still develop years later. Because the reading may look lower than the true pressure, a normal-looking number does not rule out a problem.
No. The size of the error varies from eye to eye, and it tends to be largest in eyes with higher true pressure. Correction formulas are only rough estimates. Ask your eye doctor how your reading fits with your nerve scans and visual fields instead.
No test is perfect. In studies, dynamic contour tonometry and the Corvis ST corrected reading changed the least after LASIK, PRK and SMILE, while standard Goldmann readings dropped more. Using the same method over time and checking the optic nerve matter more than any single number.
Yes. In a study comparing LASIK, SMILE and PRK, Goldmann readings dropped after all three procedures. SMILE and LASIK lowered readings more than PRK did. Tell your eye doctor about SMILE just as you would about LASIK.
There is no simple yes or no answer. The decision needs input from both your glaucoma doctor and your refractive surgeon. Steroid drops after surgery can raise pressure, and lower readings afterward make glaucoma harder to monitor.
Sources checked October 31, 2026.
This article provides general education and does not replace an individual eye examination, diagnosis or treatment plan. If you have sudden vision loss, severe eye pain, or vision that gets worse while you use steroid drops after LASIK or PRK, get eye care the same day.
