Why dry-eye screening can change the refractive surgery plan

The measurements taken before refractive surgery can be precise, but they still depend on a stable optical surface. If the tear film breaks up too quickly or the corneal surface is inflamed, some of the data used to plan surgery may become less reliable.

Dry-eye screening can affect decisions made well before surgery. Ocular-surface health may influence the reliability of measurements, the timing of treatment and, in some cases, the procedure under consideration.

Josh Ford, M.D., is part of the ophthalmology team at Eyecare Associates of New Orleans. The practice evaluates patients considering LASIK in Metairie and also provides dedicated dry-eye care.[5] Refractive measurements are more dependable when the ocular surface is stable.

Why the tear film matters before the laser ever turns on

The tear film forms the eye’s first refractive surface. Each time a person blinks, tears spread across the cornea and create a smooth optical interface through which light enters the eye.

When that layer is unstable, the quality of the optical surface can change between blinks. For someone reading an eye chart, this may show up as fluctuating clarity. For a refractive surgeon, it can also affect measurements used to understand the cornea and plan treatment.

The American Society of Cataract and Refractive Surgery’s Cornea Clinical Committee has noted that ocular-surface disease can adversely affect refractive measurements obtained before keratorefractive surgery. Its preoperative algorithm was developed specifically to help identify and treat visually significant ocular-surface disease before surgical measurements are finalized.[1]

Depending on the evaluation, refractive planning may incorporate refraction, corneal topography or tomography, corneal thickness measurements, and other diagnostic data. A surgeon needs repeatable measurements that provide a consistent picture of the eye before planning treatment.

If the tear film is unstable, treating the ocular surface before repeating measurements may provide a more reliable baseline for surgical planning.

Dry eye can affect more than comfort

Dry eye is often associated with burning, grittiness, redness, or a feeling that something is in the eye. Preoperative screening also looks beyond symptoms to the condition of the ocular surface.

Dry-eye disease can affect visual quality and tear-film stability, while LASIK itself can temporarily alter tear production and the ocular surface. A systematic review and meta-analysis of 14 studies found reductions in tear breakup time and tear production after LASIK, although the authors emphasized that additional high-quality randomized studies were needed when comparing dry-eye outcomes among refractive procedures.[2]

The FDA likewise advises prospective LASIK patients that existing dry eye can worsen after the procedure and recommends that patients be screened for the condition before surgery.[3] Its LASIK checklist specifically asks patients to consider tear production and whether dry-eye symptoms could become worse after treatment.[4]

During a refractive evaluation, the clinician also assesses whether the ocular surface is healthy and stable enough for accurate measurements and predictable healing. Someone with few symptoms may still require an objective surface evaluation, while a patient with obvious irritation may need the cause clarified before moving further through the surgical workup.

What doctors look for during ocular-surface screening

No single test captures every aspect of dry-eye disease. Clinicians often combine the patient’s symptoms with several observations or measurements because dry eye can involve tear quantity, tear stability, inflammation, eyelid disease, or dysfunction of the meibomian glands that contribute oils to the tear film.

A preoperative assessment may include:

• a symptom questionnaire or detailed dry-eye history;
• tear breakup time to assess how long the tear film remains stable after a blink;
• examination of the cornea and conjunctiva for surface staining;
• evaluation of the eyelid margins and meibomian glands;
• tear-production testing when clinically appropriate;
• additional measurements such as tear osmolarity or other ocular-surface diagnostics where available.[1]

The examination can also reveal problems related to blepharitis, meibomian gland dysfunction, or other forms of ocular-surface disease that may need attention before surgery.[1]

Clinicians interpret these findings alongside the rest of the refractive evaluation. If a corneal map varies between visits, for example, an unstable surface is one possible reason the surgeon may want to investigate before relying on that map to make a treatment decision.

If the ocular surface is unstable, the surgeon may postpone the decision and repeat testing after treatment.

Why treatment sometimes comes before final LASIK measurements

When significant ocular-surface disease is identified, the next step may be to treat the surface first and repeat selected measurements later.

The approach depends on the underlying problem. Management may involve lubrication, treatment of eyelid or meibomian gland disease, prescription therapy, or other measures selected for the individual diagnosis. Treatment is intended to stabilize the ocular surface before testing is completed.

The ASCRS preoperative algorithm recommends identifying and treating visually significant ocular-surface disease because it can affect refractive measurements and postoperative visual quality.[1]

If treatment changes tear-film stability or the corneal surface, the surgeon may repeat measurements before deciding whether and how to proceed.

When dry eye affects the reliability of testing, measurements and candidacy can be reassessed after the ocular surface has stabilized.

When dry-eye findings can influence candidacy or procedure choice

Ocular-surface findings do not automatically rule out refractive surgery. Their significance depends on severity, cause, response to treatment, and the rest of the eye examination.

Treatable ocular-surface disease may be managed before testing is repeated, while more significant findings can affect when surgery is considered. Ocular-surface findings may also influence whether LASIK or another refractive procedure is considered.

Refractive procedures can affect corneal nerves and the ocular surface differently. A 2025 systematic review and meta-analysis comparing keratorefractive lenticule extraction with femtosecond LASIK found differences in several postoperative dry-eye parameters, including tear-film stability and corneal sensitivity. The authors also noted the need for standardized protocols and longer follow-up.[6] Pre-existing ocular-surface risk is one factor clinicians may consider when comparing refractive procedures.

The FDA also includes dry-eye evaluation in LASIK candidate screening. Severe dry eye may make LASIK inappropriate, while less severe disease requires an individualized discussion of risk.[3]

A refractive evaluation also assesses whether the eye is in an appropriate condition for the planned procedure.

Eyecare Associates of New Orleans provides refractive care through its Eye Laser Institute and ocular-surface evaluation through its Dry Eye Clinic, including testing focused on tear quantity and quality.[5]

When dry eye needs treatment first, testing may need to be repeated before a refractive surgery recommendation is finalized.

References

[1] Starr, C. E., Gupta, P. K., Farid, M., Beckman, K. A., Chan, C. C., Yeu, E., Gomes, J. A. P., Ayers, B. D., Berdahl, J. P., Holland, E. J., Kim, T., Mah, F. S., & ASCRS Cornea Clinical Committee. (2019). An algorithm for the preoperative diagnosis and treatment of ocular surface disorders. Journal of Cataract & Refractive Surgery, 45(5), 669-684.https://doi.org/10.1016/j.jcrs.2019.03.023

[2] Sambhi, R. D. S., Sambhi, G. D. S., Mather, R., & Malvankar-Mehta, M. S. (2020). Dry eye after refractive surgery: A meta-analysis. Canadian Journal of Ophthalmology, 55(2), 99-106.https://doi.org/10.1016/j.jcjo.2019.07.005

[3] U.S. Food and Drug Administration. (2023). When is LASIK not for me?https://www.fda.gov/medical-devices/lasik/when-lasik-not-me

[4] U.S. Food and Drug Administration. (2023). LASIK surgery checklist.https://www.fda.gov/medical-devices/lasik/lasik-surgery-checklist

[5] Official practice facts page. (n.d.). Practice overview, provider information, refractive services, dry-eye services, and medical technology.https://eyecareneworleans.com/facts/

[6] Chen, K.-Y., Chan, H.-C., & Chan, C.-M. (2025). How effective is keratorefractive lenticule extraction surgery (KLEx) in reducing dry eye outcomes compared to LASIK? A systematic review and meta-analysis. Journal of Refractive Surgery, 41(8), e839-e854.https://doi.org/10.3928/1081597X-20250506-07