Undergoing Laser-Assisted In Situ Keratomileusis (LASIK) while having chronic dry eye disease (DED) is a common concern for individuals seeking vision correction. LASIK uses a laser to reshape the cornea and correct refractive errors, but it is known to temporarily induce or worsen dry eye symptoms in almost all patients. This post-operative dryness challenges those who already manage DED, a condition characterized by insufficient tear production or poor tear quality. Potential candidates must determine if their pre-existing ocular surface condition can be safely managed for a successful surgical outcome.
The Link Between LASIK and Post-Operative Dryness
LASIK surgery causes dryness because the procedure requires creating a thin flap on the corneal surface, which is lifted to allow the laser to reshape the underlying tissue. This action disrupts the dense network of sensory nerves located in the cornea’s outer layers. These nerves trigger the reflex arc that stimulates tear production from the lacrimal glands.
When these nerves are cut, the communication pathway is temporarily broken, leading to decreased basal and reflex tearing. Reduced nerve sensitivity also impairs the blink reflex, which spreads the tear film evenly. This results in a less stable tear film that evaporates more quickly.
Corneal nerves generally regenerate and sensation recovers over time, but this process can take three to twelve months. For patients with pre-existing DED, the temporary damage caused by the flap creation may significantly exacerbate their symptoms, requiring careful pre-operative management.
Determining Patient Eligibility
A comprehensive screening process determines if a candidate with dry eyes can safely undergo LASIK. The presence of DED before surgery is the primary risk factor for chronic post-LASIK dry eye. Doctors rely on multiple diagnostic tests to quantify the severity of the condition and assess the stability of the ocular surface.
One assessment is the Schirmer’s test, which measures tear production by placing a strip of filter paper under the lower eyelid. A normal result is typically above 15 millimeters of wetting after five minutes; a result below 5 millimeters suggests severe aqueous tear deficiency and may disqualify a patient.
Another measurement is the Tear Film Break-Up Time (TBUT), which involves applying a dye and measuring how long the tear film takes to destabilize. Tear osmolarity testing is also used, providing a measure of the salt concentration in the tears. Elevated osmolarity is a hallmark of DED and indicates an unstable tear film.
A high osmolarity score combined with low Schirmer values often leads a surgeon to disqualify a patient or mandate a pre-treatment regimen. This regimen stabilizes the ocular surface before surgery is considered.
Managing Dry Eyes Before and After Surgery
For patients with mild to moderate dry eye who are still considered candidates, a structured treatment plan is initiated weeks or months before the procedure to optimize the ocular surface. This pre-conditioning involves prescription anti-inflammatory eye drops, such as cyclosporine or lifitegrast, which work to suppress the inflammation contributing to DED. These drops help improve the quality and quantity of the patient’s natural tears.
Another strategy is the temporary or permanent insertion of punctal plugs, which are tiny devices placed in the tear drainage ducts of the eyelids. These plugs conserve the patient’s natural tears on the eye’s surface, increasing the tear volume available for lubrication. Patients are also advised to use preservative-free artificial tears frequently and take oral omega-3 fatty acid supplements to improve the lipid layer of the tear film.
Following surgery, this aggressive lubrication and anti-inflammatory protocol continues to support the healing process and manage post-operative dryness. Patients are instructed on a strict schedule for artificial tears, often every hour initially, along with continuing prescription drops for several months. This intensive post-operative management reduces discomfort and ensures the ocular surface remains healthy during corneal nerve regeneration.
Alternative Vision Correction Options
For patients with severe or unmanageable dry eye who are deemed ineligible for LASIK, several alternative refractive procedures exist that may pose a lower risk of exacerbating DED.
Photorefractive Keratectomy (PRK) is a surface ablation technique where the outermost layer of the cornea is removed and discarded before the laser reshapes the underlying tissue. Since PRK does not involve creating a deep corneal flap, it is generally associated with a lower incidence of long-term post-operative dry eye.
Small Incision Lenticule Extraction (SMILE) is a newer procedure that creates a lens-shaped piece of tissue within the cornea, which is then removed through a very small incision. Because the incision is significantly smaller than the flap created in LASIK, SMILE causes less disruption to the corneal nerves, often resulting in less post-operative dryness compared to traditional LASIK.
The Implantable Collamer Lens (ICL) is a non-laser solution where a corrective lens is placed inside the eye, typically between the iris and the natural lens. ICLs are suitable for those with chronic dry eyes or high prescriptions because the procedure does not involve reshaping or permanently altering the cornea, meaning it does not induce or worsen dry eye symptoms.