Why Dry Eye Is Under-Recognised Before Surgery
Dry eye disease is under-diagnosed in refractive surgery candidates, and its effect on the surgical pathway is routinely underestimated. Pre-existing ocular surface dysfunction changes the preoperative measurements, can worsen transiently after surgery, and influences the perceived quality of vision long after the eye has technically healed.
How Tear Film Instability Affects Results
The prevalence of dry eye in cataract surgery candidates has been documented in prospective studies to be significantly higher than self-report suggests, with a substantial proportion of asymptomatic patients showing objective signs of tear film dysfunction.¹ The same pattern holds in laser vision correction candidates: dry eye is frequently present at baseline and can be exacerbated by corneal surgery, with recurrent erosion symptoms and fluctuating vision reported for months after otherwise successful laser treatment.²
The mechanism matters for the quality of the result. An unstable tear film acts as an irregular optical surface, producing fluctuating higher-order aberrations and reduced contrast sensitivity that standard visual acuity does not capture. Measurements taken on an unstable tear film are also less reproducible, including the keratometric values that drive IOL power selection and laser treatment planning.³
For patients choosing between laser, lens replacement, and ICL, the pre-existing dry eye profile shapes the decision. The ICL does not ablate corneal tissue and is often preferred in patients with significant baseline dry eye. For laser candidates, treating ocular surface dysfunction before surgery is a prerequisite for predictable vision quality, not a courtesy.
References
- Trattler WB, Majmudar PA, Donnenfeld ED, McDonald MB, Stonecipher KG, Goldberg DF. The Prospective Health Assessment of Cataract Patients’ Ocular Surface (PHACO) study: the effect of dry eye. Clin Ophthalmol. 2017;11:1423–1430.
- Hovanesian JA, Shah SS, Maloney RK. Symptoms of dry eye and recurrent erosion syndrome after refractive surgery. J Cataract Refract Surg. 2001;27(4):577–584.
- Epitropoulos AT, Matossian C, Berdy GJ, Malhotra RP, Potvin R. Effect of tear osmolarity on repeatability of keratometry for cataract surgery planning. J Cataract Refract Surg. 2015;41(8):1672–1677.
Related Topics
- Why Vision Outcomes Vary After Refractive Surgery – The Four-Domain Model
- Why do patients with the same prescription get different vision after surgery?
- How much of the final result is biology versus planning versus execution?
- Why does lens power calculation matter more than the lens itself?
- How do corneal shape and tear film affect final vision quality?
- Why do some patients take longer than others to neuroadapt to a new IOL?
- How does pre-existing dry eye change vision quality after laser or ICL?
- Why do realistic expectations correlate with better perceived outcomes?
- How much does surgical execution actually affect final vision quality?
- Why can two eyes in the same patient recover differently?
- What the surgeon controls versus what the eye decides
- What increases the risk of a poor outcome?
