Quick Answer
Yes. LASIK effectively corrects most forms of astigmatism. The excimer laser reshapes the cornea to eliminate the irregular curvature that causes blurred vision. Most patients with up to 5.00 diopters of astigmatism are good candidates. Topography-guided LASIK (Contoura Vision) produces particularly strong results for astigmatism, including corneal irregularities that standard LASIK does not fully address.
Detailed Explanation
Astigmatism is one of the most common refractive errors — and one of the most commonly misunderstood. Many patients assume they are not candidates for LASIK because of their astigmatism diagnosis. In most cases, this assumption is incorrect.
What astigmatism actually is
A healthy cornea is spherical — like a basketball. Astigmatism occurs when the cornea (or, less commonly, the crystalline lens) is shaped more like a football, with different curvatures along different axes. Light entering the eye focuses at multiple points instead of one, producing blurry or distorted vision at all distances.
Astigmatism is measured in diopters (D) along with its axis (the angle of the steepest curvature). A prescription reading “-2.00 -1.75 x 090” means -2.00 diopters of myopia, -1.75 diopters of astigmatism, with the axis at 90 degrees.
How LASIK corrects astigmatism
The excimer laser removes corneal tissue in a precise, asymmetric pattern that reshapes the cornea to be more uniformly spherical. For astigmatism, the laser removes more tissue along one meridian than another, equalizing the curvature. The result is light focusing at a single point — and clear vision.
Modern wavefront-guided and topography-guided platforms treat astigmatism with greater precision than earlier generation lasers, achieving better uncorrected visual acuity outcomes across multiple clinical studies.
What prescription ranges qualify
FDA-approved laser platforms cover the following astigmatism ranges for LASIK:
- VISX Star S4 IR / iDesign: Up to -6.00 D of astigmatism combined with myopia up to -11.00 D
- Alcon WaveLight Allegretto / EX500: Up to -6.00 D of astigmatism
- Topography-guided (Contoura): Up to -3.00 D of astigmatism with up to -9.00 D of myopia (FDA-labeled), though off-label treatments for higher ranges are performed by experienced surgeons
Surgeons can perform treatments outside labeled parameters at their clinical judgment, but most prefer to stay within approved ranges for predictability.
Topography-guided LASIK: the best option for astigmatism
Standard LASIK treats the patient’s manifest refraction — the prescription measured in a standard exam. Topography-guided LASIK (marketed as Contoura Vision) treats the corneal surface directly, using thousands of data points from corneal topography to guide the laser.
For patients with higher-order aberrations alongside astigmatism — subtle irregularities in the corneal surface beyond simple cylinder — topography-guided treatment consistently outperforms wavefront-guided treatment. FDA clinical trials showed that 30% of Contoura patients achieved 20/16 or better uncorrected vision, compared to the typical 20/20 benchmark.
Irregular astigmatism: a different situation
Irregular astigmatism — caused by corneal scars, irregular corneal shape, or early keratoconus — is a different clinical situation. In these cases:
- LASIK may be contraindicated if corneal irregularity is caused by or associated with keratoconus
- Topography-guided LASIK can address some forms of irregular astigmatism caused by prior surgery or injury
- CXL + LASIK combinations are used in select keratoconus patients with stable disease
Proper screening is essential. Irregular astigmatism that mimics regular astigmatism on simple topography but is actually early keratoconus is one of the most serious screening failures in refractive surgery.
LASIK Surgery Awards evaluates practices on the sophistication of their astigmatism screening and treatment protocols — both because it affects a large proportion of candidates and because it is an area where technology investment makes a measurable difference in outcomes.
Important Considerations
Your contact lens prescription and glasses prescription may differ. Toric contact lenses correct astigmatism, but the power in your contact prescription is not the same as in your glasses prescription. For LASIK planning, the cycloplegic refraction (measured with dilating drops) and corneal topography are more important than either prescription.
High astigmatism may require more corneal tissue removal. Treating significant astigmatism requires asymmetric ablation that consumes more tissue than treating spherical myopia alone. Patients with higher astigmatism and borderline corneal thickness require careful planning.
Residual astigmatism after LASIK is treatable. A small amount of residual astigmatism (0.25–0.50 D) after LASIK is common and may not affect visual quality. Residual amounts above 0.75 D that affect vision can be addressed with an enhancement procedure.
Lenticular astigmatism does not respond to corneal laser surgery. If your astigmatism originates primarily in the crystalline lens rather than the cornea, laser surgery on the cornea may not fully correct it. This is uncommon but worth discussing with your surgeon after corneal tomography.
What to Do Next
1. Get a comprehensive LASIK evaluation that includes corneal topography and tomography. This distinguishes regular from irregular astigmatism and confirms candidacy. 2. Ask specifically about topography-guided treatment if your astigmatism is above 1.00 D or if you have any known corneal irregularity. 3. Bring your current glasses and contact lens prescriptions to your consultation for comparison. 4. Discuss enhancement expectations if your prescription includes significant cylinder, since treatment of high astigmatism has slightly more variability than treatment of myopia alone.
For a broader overview of what determines LASIK candidacy, see What Disqualifies You from Getting LASIK?.
Related Questions
Wondering about the difference between LASIK and SMILE for astigmatism correction? Read What Is the Difference Between LASIK and SMILE? for a comparison of both approaches.
Concerned about what happens if results are not ideal? See What Happens If LASIK Fails? for information on enhancement surgery and alternative correction options.
Not sure whether your prescription range qualifies at all? Read What Disqualifies You from Getting LASIK? for a complete candidacy overview.