Enhancement following LASIK is uncommon but well recognised. Rates vary depending on starting refractive error, corneal characteristics and duration of follow-up.
Large retrospective series analysing thousands of procedures report enhancement rates between 2% and 10%, with higher rates observed in patients with higher pre-operative myopia and astigmatism¹. In long-term follow-up studies, myopic regression contributes to a proportion of enhancements, particularly in younger patients².
The relationship between starting prescription and enhancement is mathematically intuitive. A small proportional change in corneal response produces a larger absolute refractive deviation when beginning at –8.00 D compared with –1.00 D. Higher cylinder corrections are also axis-sensitive, meaning small rotational variance can influence final outcome.
Modern laser platforms have significantly improved predictability. Contemporary outcome analyses demonstrate excellent uncorrected visual acuity and safety profiles, with very low rates of vision-threatening complications³.
Enhancement therefore reflects biological variability rather than surgical inaccuracy.
Key predictors of enhancement include:
- Higher spherical equivalent
- Younger patient age
- Thinner corneas requiring conservative initial treatment
- Epithelial remodelling patterns
When residual stromal bed is preserved during primary surgery, enhancement can usually be performed safely if required. Conservative initial planning therefore protects future options.
Enhancement is statistical, not symptomatic of poor technique.
References
- Randleman JB, White AJ, Lynn MJ, Stulting RD. Incidence, outcomes, and risk factors for retreatment after LASIK. Ophthalmology. 2009;116(11):2100-2107.
- O’Doherty M, Kirwan C, O’Keeffe M. Long-term results of LASIK for myopia. Br J Ophthalmol. 2006;90(1):20-23.
- Sandoval HP, Donnenfeld ED, Kohnen T, et al. Modern LASIK outcomes. J Cataract Refract Surg. 2016;42(8):1224-1234.
Related Topics
- Does an Enhancement After Laser or Lens Replacement Surgery Mean Something Went Wrong?
- What Is a Laser Eye Surgery Enhancement?
- How Common Is Enhancement After LASIK?
- Why Are Higher Prescriptions More Likely to Require Enhancement?
- Why Do Hyperopic Laser Treatments Regress More Frequently?
- Why Is Residual Hyperopia After Lens Surgery Different?
- How Is LASIK Enhancement Performed?
- How Is Enhancement Performed After SMILE?
- What Is Residual Stromal Bed and Why Does It Matter?
- Can Enhancement Affect Night Vision or Optical Quality?
- When Should Enhancement Not Be Performed?
- How Long Should You Wait Before Laser Enhancement?
- What Causes Regression After Laser Eye Surgery?
- What Is Topography-Guided Enhancement?
- Can Enhancement Increase Glare or Halos?
- Why Does Astigmatism Sometimes Remain After Laser Eye Surgery?
- What Is Epithelial Remodelling and Why Does It Matter?
- Is Enhancement Safer Than Intraocular Lens Exchange?
- What Is the Risk of Ectasia After Enhancement?
- Does Enhancement Affect Long-Term Vision Quality?
- What Does an Enhancement Cost?
