SMILE in one eye vs Ray tracing-guided LASIK in the fellow eye
Official title: A Prospective Randomized Comparison of SMILE Surgery to Ray Tracing-Guided LASIK Surgery
Run by Stanford University · NCT07721714 · Data updated 2026-11-12
This study tests two laser vision correction methods—SMILE in one eye and ray-tracing guided LASIK in the other eye—to see which provides better vision and quality of life for adults with myopia and astigmatism.
Quick facts
| Phase | Phase 4 |
|---|---|
| Study type | Interventional |
| Ages | 22 Years to 59 Years |
| Sex | All |
| Enrollment | 62 (estimated) |
| Sponsor | Stanford University Academic / other |
| Locations | 1 site (Palo Alto, California) |
| Status | Recruiting |
| Started | August 5, 2026 |
| Main results expected | December 31, 2028 |
| Study ends | July 31, 2029 |
| Registry record updated | August 26, 2026 |
| Trial ID | NCT07721714 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Adults aged 22 or older with stable myopia (-1.00 to -8.00 D) and astigmatism up to 3.00 D, with similar refractive levels in both eyes and suitable corneal anatomy.
✕Probably not a fit
Individuals with very thin corneas, keratoconus, ectatic disorders, significant systemic autoimmune disease, pregnancy or nursing, or large inter-eye refractive discrepancies may not benefit.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This interventional study compares two FDA-approved laser eye procedures within the same participant. Each participant has one eye treated with ray tracing-guided LASIK and the other eye with SMILE, with random assignment of which eye receives which treatment. Outcomes include uncorrected and best-corrected visual acuity, refractive accuracy, low-contrast vision, and quality-of-life measures collected before and after surgery using validated questionnaires. The trial involves 62 myopic adults at Stanford who meet specific refractive and corneal criteria. Safety and effectiveness data from this intra-individual comparison will inform whether one approach offers superior patient-perceived vision and daily functioning.
Why it matters
Potential benefit: If successful, patients may experience better overall vision and quality of life with one of the procedures, potentially guiding personalized eye laser treatment choices.
How similar studies have gone: Previous studies have shown both SMILE and ray-tracing LASIK to be safe and effective, but this direct intra-individual, eye-by-eye comparison is relatively novel.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: Subjects age 22 and older with healthy eyes. Nearsightedness between -1.00 diopters and -8.00 diopters. Subjects with less than or equal to 3.00 diopters of astigmatism. Exclusion Criteria: Subjects under the age of 22. Subjects with excessively thin corneas. Subjects with topographic evidence of keratoconus. Subjects with ectactic eye disorders. Subjects with autoimmune diseases. Subjects who are pregnant or nursing. Subjects must have similar levels of nearsightedness in each eye. They can not be more than 1.5 diopter of difference between eyes. Subjects with more than 3.00 diopters of astigmatism Subjects must have similar levels of astigmatism in each eye. They can not have more than 0.75 diopters of difference between eyes.
Where it's running
-
Byers Eye Institute
Palo Alto, California, United States Recruiting
Study contacts
- Study coordinator: Edward E Manche, MD
- Email: edward.manche@stanford.edu
- Phone: 1-650-498-7020
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.