CompletedNCT03067077Updated Feb 2, 2022Results posted

A Prospective, Contralateral, Eye to Eye Comparison of SMILE Surgery to LASIK Surgery

An interventional study of SMILE and LASIK in Myopia, sponsored by Stanford University. Completed at 1 site in United States. Open to participants aged 22 Years to 59 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-02-02.

Sponsored by Stanford University · Not applicable, Interventional, and Treatment

Phase: Not applicable
Study type: Interventional
Enrollment: 44
Allocation: Randomized
Ages: 22 Years to 59 Years
Sex: All

Study summary

Subjects will undergo SMILE surgery in one eye and LASIK surgery in their other eye to correct myopia.

Read the detailed description

Subjects will have a comprehensive eye examination once they express an interest in the study. This includes a slit lamp examination of the front of the eye and a dilated fundoscopic examination of the back of the eye. If there is any pathology noted that would exclude the subject from the study, then we will inform the patient and make an appropriate referral. if the subject is deemed appropriate for the study after a comprehensive examination included computerized videokeratography, then they can be enrolled. Subjects will undergo bilateral simultaneous eye surgery. Which eye is treated with the WFG-LASIK and which eye is treated with SMILE will be randomized so there is a 50% chance for either eye to receive one treatment. Subjects will be seen on the day of surgery, post op day one, one week, one month, three months, six months and one year. Subjects will receive topical antibiotics in each eye for one week following the procedure. Subjects will receive topical steroid ophthalmic drops for one week after treatment. Subjects will also receive topical antibiotic ophthalmic drops for four days after treatment. All of this is within the usual and customary standard of care for the treatment of subjects undergoing LASIK and SMILE surgery.

Conditions studied

Myopia

Browse trials for

Myopia 1,007

Keywords

SMILE
LASIK
Myopia
Wavefront-guided

In context

Myopia

1,007 studies on the registry are indexed under Myopia; 210 are open to participants now.

This study's enrollment of 44 is below the median of 80 across 803 interventional studies indexed under Myopia.

Browse Myopia studies →

Lead sponsor

Stanford University is the lead sponsor of 2,161 studies on the registry; 428 are open to participants now.

Of its 268 completed or terminated interventional studies of FDA-regulated products, 207 (77%) have results posted.

Browse Stanford University studies →

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 22 Years to 59 Years
Sexes eligible: All
Accepts healthy volunteers: Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

Subjects age 22 and older with healthy eyes. Nearsightedness between -0.75 diopters and -8.00 diopters.
Subjects with up to 3.00 diopters of astigmatism.

Exclusion criteria

Exclusion Criteria:

Subjects under the age of 22.
Subjects with excessively thin corneas.
Subjects with topographic evidence of keratoconus.
Subjects with ectatic 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 3.25 or more diopters of astigmatism
Subjects must have similar levels of astigmatism in each eye. They can not have more than 0.50 diopters of difference between eyes.

Study design

Phase: Not applicable
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel assignment
Masking: None (open label)
Enrollment: 44 participants (actual)

Study arms

Active comparator
SMILE
SMILE surgery
Procedure: SMILE · Procedure: LASIK
Active comparator
Wavefront-guided LASIK
Wavefront-guided LASIK
Procedure: SMILE · Procedure: LASIK

Interventions

ProcedureSMILE
SMILE surgery
ProcedureLASIK
LASIK surgery

What researchers measure

Primary outcomes

Percentage of Participant Eyes With an Uncorrected Visual Acuity of 20/20 or Better
ETDRS testing lane
Time frame: One year

Secondary outcomes

Number of Participant Eyes Losing 2 or More Lines of Corrected Distance Visual Acuity
ETDRS testing lane
Time frame: One year
Aberrometry Measurements
Increase in total higher order RMS (root mean squared) by greater than 0.5 microns
Time frame: One year
Patient Satisfaction
Percentage of patients satisfied with surgery. Patients were asked yes or no.
Time frame: One year
Change in Corneal Sensation
A decrease in corneal sensation of more than 4 cm as measured by Cochet-Bonnet Aesthesiometry
Time frame: One year
Dry Eye Symptoms as Measured by OSDI Index
Worsening of ocular surface disease index (OSDI) score of greater than 25. The overall OSDI score defined the ocular surface as normal (0-12 points) or as having mild (13-22 points), moderate (23-32 points), or severe (33-100 points) disease.
Time frame: One year
Analysis of Astigmatism
Participant eyes with an increase in astigmatism of greater than 1.0 diopter
Time frame: One year
Anterior Segment Ocular Coherence Topography Analysis
Humphrey Visante AS OCT
Time frame: One year
Predictability
Number of eyes within +/- 0.5 and +/- 1.00 diopter of the intended correction
Time frame: One year
Stability
Change in refractive error greater than one diopter over 1 to 12 months
Time frame: One year

Results

Posted Feb 2, 2022

Participant flow

Enrolled participants were to receive SMILE surgery in one eye and LASIK surgery in their fellow eye

Participant flow — Overall Study
Milestone	SMILE	Wavefront-guided LASIK
Started	44	44
Received surgery	40	39
Completed	37	37
Not completed	7	7
Withdrew: Did not receive surgery	4	5
Withdrew: Lost to follow-up	3	2

Outcome measures

PrimaryPercentage of Participant Eyes With an Uncorrected Visual Acuity of 20/20 or Better

ETDRS testing lane

Time frame:: One year
Reported as:: Number · percentage of participant eyes

Percentage of Participant Eyes With an Uncorrected Visual Acuity of 20/20 or Better
percentage of participant eyes	SMILE	Wavefront-guided LASIK
Percentage of Participant Eyes With an Uncorrected Visual Acuity of 20/20 or Better	94	83

SecondaryNumber of Participant Eyes Losing 2 or More Lines of Corrected Distance Visual Acuity

ETDRS testing lane

Time frame:: One year
Reported as:: Count of units · Eyes

Number of Participant Eyes Losing 2 or More Lines of Corrected Distance Visual Acuity
Eyes	SMILE	Wavefront-guided LASIK
Number of Participant Eyes Losing 2 or More Lines of Corrected Distance Visual Acuity	0	0

SecondaryAberrometry Measurements

Increase in total higher order RMS (root mean squared) by greater than 0.5 microns

Time frame:: One year
Reported as:: Count of units · Eyes

Aberrometry Measurements
Eyes	SMILE	Wavefront-guided LASIK
Aberrometry Measurements	0	0

SecondaryPatient Satisfaction

Percentage of patients satisfied with surgery. Patients were asked yes or no.

Time frame:: One year
Reported as:: Count of participants · Participants

Patient Satisfaction
Participants	SMILE	Wavefront-guided LASIK
Patient Satisfaction	36	36

SecondaryChange in Corneal Sensation

A decrease in corneal sensation of more than 4 cm as measured by Cochet-Bonnet Aesthesiometry

Time frame:: One year
Reported as:: Count of units · Eyes

Change in Corneal Sensation
Eyes	SMILE	Wavefront-guided LASIK
Change in Corneal Sensation	0	0

SecondaryDry Eye Symptoms as Measured by OSDI Index

Worsening of ocular surface disease index (OSDI) score of greater than 25. The overall OSDI score defined the ocular surface as normal (0-12 points) or as having mild (13-22 points), moderate (23-32 points), or severe (33-100 points) disease.

Time frame:: One year
Reported as:: Count of participants · Participants

Dry Eye Symptoms as Measured by OSDI Index
Participants	SMILE	Wavefront-guided LASIK
Dry Eye Symptoms as Measured by OSDI Index	0	0

SecondaryAnalysis of Astigmatism

Participant eyes with an increase in astigmatism of greater than 1.0 diopter

Time frame:: One year
Reported as:: Count of units · Eyes

Analysis of Astigmatism
Eyes	SMILE	Wavefront-guided LASIK
Analysis of Astigmatism	0	0

SecondaryAnterior Segment Ocular Coherence Topography Analysis

Humphrey Visante AS OCT

Time frame:: One year

No measurements were reported for this outcome.

SecondaryPredictability

Number of eyes within +/- 0.5 and +/- 1.00 diopter of the intended correction

Time frame:: One year
Reported as:: Count of units · Eyes

Predictability
Eyes	SMILE	Wavefront-guided LASIK
+/- 0.50 diopters	30	34
+/- 1.0 diopters	36	37

SecondaryStability

Change in refractive error greater than one diopter over 1 to 12 months

Time frame:: One year
Reported as:: Count of units · Eyes

Stability
Eyes	SMILE	Wavefront-guided LASIK
Stability	0	0

Adverse events

Collected over 12 months. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
SMILE	0/44 (0%)	0/44 (0%)	1/44 (2.3%)
Wavefront-guided LASIK	0/44 (0%)	0/44 (0%)	0/44 (0%)

Most frequent other events

Most frequent other events
Event	SMILE	Wavefront-guided LASIK
Unable to remove SMILE lenticuleEye disorders	1/44	0/44

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)	All Participants
<=18 years	0
Between 18 and 65 years	44
>=65 years	0

Sex: Female, Male
Sex: Female, Male(Participants)	All Participants
Female	21
Male	23

Race/Ethnicity, Customized
Race/Ethnicity, Customized(Participants)	All Participants
Asian	19
Caucasian	18
Hispanic	2
Indian	4
Pacific Islander	1

Region of Enrollment
Region of Enrollment(Participants)	All Participants
United States	44

Study locations

1 site

Byers Eye Institute at Stanford
Palo Alto, California 94303, United States

References and documents

Publications

Chiang B, Valerio GS, Manche EE. Prospective, Randomized Contralateral Eye Comparison of Wavefront-Guided Laser In Situ Keratomileusis and Small Incision Lenticule Extraction Refractive Surgeries. Am J Ophthalmol. 2022 May;237:211-220. doi: 10.1016/j.ajo.2021.11.013. Epub 2021 Nov 14. PubMed 34788593 ↗
Ma KK, Manche EE. Patient-reported quality of vision in a prospective randomized contralateral-eye trial comparing LASIK and small-incision lenticule extraction. J Cataract Refract Surg. 2023 Apr 1;49(4):348-353. doi: 10.1097/j.jcrs.0000000000001127. PubMed 36539217 ↗

Study documents

Study protocol · Oct 6, 2020

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

Timeline

Tracking since Sep 25, 2026

ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Mar 2017 to primary completion in Mar 2021, 48 months.

Results were first posted in Feb 2022, 10 months after primary completion.

Of 195 non-industry interventional studies with no phase under Myopia, half reached primary completion within 26 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 46. This study's 48 months is above that.

Counting every sponsor, half of 379 studies reached it within 19 months; a quarter within 5 and three quarters within 37.

How these figures are worked out, and which studies are left out of them.

Registered: Feb 16, 2017
First posted: Mar 1, 2017
StartActual: Mar 12, 2017
Primary completionActual: Mar 15, 2021
CompletionActual: Mar 15, 2021
Results first posted: Feb 2, 2022
Last update: Feb 2, 2022

What these dates mean

Start.: When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.: When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.: When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.: Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.

No changes since tracking began. The registry record was last updated on Feb 2, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT03067077
Lead sponsor: Stanford University
Responsible party: Edward E. Manche (Professor of Ophthalmology, Stanford University) — Principal investigator
First posted: Mar 1, 2017
Start date: Mar 12, 2017
Primary completion: Mar 15, 2021
Completion: Mar 15, 2021
Results posted: Feb 2, 2022
Last update: Feb 2, 2022

Study contacts

Edward E Manche, MD

principal investigator · Stanford University

Oversight

Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: Yes

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Jan 2022. You cannot join it, but the record below documents what was studied.

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